What is a cement concrete road? – The cement concrete roads are in the form of monolithic slabs of cement concrete which serve two functions simultaneously, namely, as the load-carrying base and as the wearing surface, According to the structural behavior, the pavements can be classified as flexible pavement or rigid pavement,

1. Bituminous concrete is one of the best flexible pavement layer materials.
2. Various other types of bituminous roads are considered as flexible pavements.
3. The cement concrete roads, on the other hand, are treated rigid pavements because of their rigidity.
4. Cement concrete road is a highly rigid surface and hence, for the success of such roads, the following two conditions should be satisfied : (i) They should rest on non-rigid surface having uniform bearing capacity.

(ii) The combined thickness or depth of the concrete pavement and the non-rigid base should be sufficient to distribute the wheel load on a sufficient area of the sub-base so that the pressure on the unit area remains within the permissible safe bearing capacity of the soil. concrete-pavements

What is meant by concrete road?

An overview of concrete road construction Concrete roads are made using a concrete mix of portland cement, coarse aggregate, sand, and water. The most important advantage of a Concrete Road is its service life due to exceptional durability. They are considerably less prone to wear and tear defects like rutting, cracking, stripping loss of texture, and potholes that can occur with flexible pavement surfaces.

Right thickness to distribute the wheel load stresses to a safe value on the sub-grade soilDurable to withstand all types of stresses imposed upon itAdequate coefficient of friction to prevent skidding of vehicles,Smooth surface to provide comfort to road usersImpervious surface, so that sub-grade soil is well protectedLong design life with low maintenance costThe thickness should be adequate to transmit the applied loads and distribute them onto a larger area of the soil belowHard-wearing surface so as to resist the abrasion caused by vehicle tyres

Types of concrete roads pavements Jointed Plain Concrete Pavement (JPCP) – Jointed plain concrete pavement uses contraction joints to control cracking and does not use any reinforcing steel. Transverse joint spacing is selected such that temperature and moisture stresses do not produce intermediate cracking between joints.

1. Jointed Reinforced Concrete Pavement (JRCP) – Jointed reinforced concrete pavements (JRCP) contain steel mesh reinforcement (sometimes called distributed steel).
2. In JRCP, designers intentionally increase the joint spacing and include reinforcing steel to hold together mid-panel cracks.
3. Continuously Reinforced Concrete Pavement (CRCP) – Continuously reinforced concrete pavement (CRCP) contains continuous, longitudinal steel reinforcement without transverse joints, except where required for end-of-day header joints, at bridge approaches, and at transitions to other pavement structures.

Continuous reinforcement is a strategy for managing the transverse cracking that occurs in all new concrete pavements. In new concrete pavements, volumetric changes caused by cement hydration, thermal effects, and external drying are restrained by the pavement base layer and longitudinal reinforcement causing tensile stresses to develop in the concrete. Continuously Reinforced Concrete Pavement Methods of construction of concrete road The concrete roads can either be constructed in a single course or two courses. In single course pavement, or two courses. In single course pavement, the entire depth of concrete is composed of homogeneous material.

The concrete is laid in two courses or layers of equal or different depths with different concrete compositions with three different types of methods. Alternate Bay Method: taken up in alternate bays; the bays left in the first instance are done after the concrete already laid gets hardened adequately-one week in the case of ordinary Portland cement and two to three days for rapid hardening cement.

Continuous Method: the bays of one lane are laid continuously; however, construction joints are provided at the end of the day’s work. Expansion joint and strip method: the road is divided into longitudinal strips and transverse bays using timber formwork. Jointed Plain Concrete Pavement

Structural components of concrete roads The concrete roads consist of the following components : Surface Course

It is the topmost layer; its function is to provide a smooth, strong, abrasion-resistant and reasonably impervious course. Since it is directly in contact with the vehicle tyres, it has to resist the imposed wheel loads and transmit them safely to the layer below.

The material may be granular, bituminous or cement concrete depending upon the nature of the construction. For flexible pavements, the bituminous surface is the wearing course whereas in rigid pavement the concrete surface act as the base course cum wearing course. Base course It is below the surface course and its function is to distribute the stresses transmitted through the surface course evenly onto the layers below.

Invariably, it consists of granular or bituminous material, and acts as a structural part of the pavement. The base course is the most important layer of a road structure which transfers the stresses developed due to traffic impacts through the wearing course.

• The base course layer provides the required foundation stiffness and structural strength.
• Sub-Base Course It is just below the base course and provides additional help to the courses above it in distributing the loads.
• It also helps in preventing soil grains of the subgrade from intruding into the base course above, and counteracts frost action, if any.

It may consist of stabilised soil or soil aggregate mixes, which facilitate drainage of free water from the pavement. It comes between the base course and subgrade. The material used for this layer shall satisfy the specifications in terms of gradation, strength, and plastic characteristics.

1. This layer is necessary if the subgrade is of poor quality.
2. Subgrade It is the compacted natural soil immediately below the pavement layers; this acts as a foundation for the highway.
3. The top surface of the subgrade is called the formation level.
4. Based on the alignment and the nature of the terrain, a roadway may be constructed over an embankment or a cutting, or at or nearly at the natural ground level.

The formation of level, therefore, has to be properly decided to suit these conditions. It serves as the foundation and acts as a uniform support to pavements. Subgrades bear the entire load of the payments along with the service load of traffic Concrete road The construction of concrete road involves the following steps;

Preparation of Subgrade- shaped, and leveled. After cleaning, it is prepared to the required grade and profile.Placing the forms- Forms are properly braced and fixed to the ground using stakes. The forms are oiled before placing concrete in them.Watering the Prepared Subgrade- forms are fixed, the prepared surface to receive concrete is made moist. It must be sprinkled with as much quantity of water as it can absorb.Batching of Materials- the proportions of ingredients for the concrete mix, the fine and coarse aggregates are properly proportionedTransporting and laying the concrete mix- the concrete is transported to the site. The mixed concrete is deposited rapidly on the sub-grade in a layer of thickness.Compaction- done with a heavy screed or tamper fitted with suitable handles. Concrete is also compacted using a power-driven finishing machine, vibrating hand screed and slabs screed vibrator.Floating- done to provide an even surface free from corrugations.Belting- done just before the concrete becomes hardBrooming – drawing brushes at right angles to the centerline of the road from edge to edgeEdging- the edges of the slab are carefully finished with an edging tool before the concrete is finally set.Joint filling- properly with a suitable sealing compoundCuring- checking the loss of water from the concrete slab, and keeping the fresh concrete slab moist during a hardening periodOpening of traffic- opening after attaining required strength

Conclusion Concrete is capable of withstanding heavy loads, such as heavy vehicles, with less deformation. It serves for years without major repairs. Several factors affect concrete pavement performance, such as traffic, soil, environmental, economic and stress distribution factors.

What are the type of pavement?

Types of pavement in road construction – There are two main types of pavement: rigid pavement (consisting of one layer) and flexible pavement (typically made up of multiple layers). Pavements are often made of asphalt or concrete, but they can also be constructed from artificial stone, flagstone, cobblestone, bricks, tiles or even timber. Cross section of modern pavements. (Left) Flexible asphalt-based pavement. (Right) Rigid Portland cement concrete pavement. Source: https://www.britannica.com/technology/flexible-pavement

What is the most commonly used type of concrete pavement?

Highway Engineering Questions and Answers – Cement Concrete Pavements This set of Highway Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Cement Concrete Pavements”.1. What is the most commonly used type of concrete pavement? a) Unreinforced b) RCC c) Fibre reinforced d) Continous View Answer Answer: a Explanation: The most commonly used type is unreinforced, dowels and ties are not considered as reinforcements in slab.

2. The pavement is checked for _ a) Tension b) Shear c) Flexure d) Compression View Answer

Answer: c Explanation: The pavement is checked for flexure because it is the factor which leads to cracks.3. What is the maintenance cost of rigid pavement when compared to the flexible pavement? a) More b) Less c) Equal d) Depends on grade of concrete View Answer Answer: b Explanation: The cost of maintenance for rigid pavement is always less than that for flexible pavement.4.

• The critical stresses affecting the reinforced pavement is _ a) Heavy loading b) Poor soil c) Poor drainage d) All of the mentioned View Answer Answer: d Explanation: The extreme conditions are due to all the factors, but when they are combined the worst may occur.5.
• The steel reinforcement is placed at _ a) 1/2 of depth b) 1/3 of depth c) 1/4 of depth d) 1/6 of depth View Answer Answer: a Explanation: The steel reinforcement is usually provided at half or a little more than half of the depth.

Check this: | 6. The excessive flexural stress can lead to _ a) Cracks b) Bending c) Torsion d) Settlement View Answer Answer: a Explanation: The bending can resist a maximum flexural stress and if it exceeds it leads to cracks.7. The CC slab can be constructed in how many methods? a) One b) Two c) Three d) Four View Answer Answer: b Explanation: CC pavement can be constructed by using slip form paver and fixed aide forms, which are the two most commonly used methods.8.

The standard normal varaite in India is taken as _ a) 1 b) 1.65 c) 1.7 d) 1.9 View Answer Answer: b Explanation: The standard normal variate is taken as 1.65, for concrete in India, it varies from county to country.9. The positive tolerance level of sub grade in surface for concrete pavement is _ a) 20 mm b) 25 mm c) 30 mm d) 35 mm View Answer Answer: a Explanation: The maximum positive tolerance level for concrete pavement is taken as + 20 mm and negative is – 25 mm.10.

The expansion joints do not consist of _ a) Dowel bars b) Joint filler c) Joint sealer d) Tack coat View Answer Answer: d Explanation: An expansion joint consists of dowel, joint filler and joint sealer, tack coat is used in bitumen surfaces. Sanfoundry Global Education & Learning Series – Highway Engineering.

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What are cement roads called?

What is a cement concrete road? – The cement concrete roads are in the form of monolithic slabs of cement concrete which serve two functions simultaneously, namely, as the load-carrying base and as the wearing surface, According to the structural behavior, the pavements can be classified as flexible pavement or rigid pavement,

1. Bituminous concrete is one of the best flexible pavement layer materials.
2. Various other types of bituminous roads are considered as flexible pavements.
3. The cement concrete roads, on the other hand, are treated rigid pavements because of their rigidity.
4. Cement concrete road is a highly rigid surface and hence, for the success of such roads, the following two conditions should be satisfied : (i) They should rest on non-rigid surface having uniform bearing capacity.

(ii) The combined thickness or depth of the concrete pavement and the non-rigid base should be sufficient to distribute the wheel load on a sufficient area of the sub-base so that the pressure on the unit area remains within the permissible safe bearing capacity of the soil. concrete-pavements

Why is concrete pavement called a rigid pavement?

Prof. Satish Chandra, Ph.D. Director, CSIR-Central Road Research Institute, Delhi Two types of pavements are laid in India-rigid pavement and flexible pavement. In simple terms, a flexible pavement can be defined as a pavement layer comprising of a mixture of aggregates and bitumen, heated and mixed properly and then laid and compacted on a bed of granular layer. Flexible Pavement Cross-section courtesy: www.theconstructor.org A typical flexible pavement consists of a bituminous surface course over base course and sub-base course. The surface course may consist of one or more bituminous or Hot Mix Asphalt (HMA) layers.

1. These pavements have negligible flexure strength and hence undergo deformation under the action of loads.
2. The structural capacity of flexible pavements is attained by the combined action of the different layers of the pavement.
3. The load from trucks is directly applied on the wearing course, and it gets dispersed (in the form of a truncated cone) with depth in the base, sub base, and subgrade courses, and then ultimately to the ground.

Since the stress induced by traffic loading is highest at the top, the surface layer has maximum stiffness (measured by resilient modulus) and contributes the most to pavement strength. The layers below have lesser stiffness but are equally important in the pavement composition.

The subgrade layer is responsible for transferring the load from the above layers to the ground. Flexible pavements are designed in such a way that the load that reaches the subgrade does not exceed the bearing capacity of the subgrade soil. Consequently, the thicknesses of the layers above the subgrade vary depending upon strength of soil affecting the cost of a pavement to be constructed.

Rigid Pavements Rigid Pavement Cross-Section courtesy: www.theconstructor.org Rigid pavements are named so because of the high flexural rigidity of the concrete slab and hence the pavement structure deflects very little under loading due to the high modulus of elasticity of their surface course.

The concrete slab is capable of distributing the traffic load into a large area with small depth which minimizes the need for a number of layers to help reduce the stress. The most common type of rigid pavement consists of dowel bars and tie bars. Dowel bars are short steel bars that provide a mechanical connection between slabs without restricting horizontal joint movement.

Tie bars on the other hand, are either deformed steel bars or connectors used to hold the faces of abutting slabs in contact. Although they may provide some minimal amount of load transfer, they are not designed to act as load transfer devices and are simply used to ‘tie’ the two concrete slabs together. Difference between Flexible Pavements and Rigid Pavements courtesy: www.theconstructor.org Design Strategy The design of pavement varies with soil conditions and the amount of traffic expected to be carried during its design life. Flexible pavements in India are designed based on California bearing ratio (CBR) of subgrade soil and expected number of cumulated axles (measured in million standard axles, msa) during the design life of the pavement.

These pavements are designed for a period of 15 years. The method of design allows use of conventional as well as stabilized materials in any layer of the pavement, and thickness of each layer is taken from the templates given in Indian Roads Congress (IRC) design code. Rigid pavements are designed for a period of 30-40 years and thickness design of rigid pavements are influenced by traffic loading, subgrade soil, moisture, and temperature differential.

First, the thickness of rigid pavements is designed for fatigue failure. The computed thicknesses of the pavements are then checked for the critical combination of load stresses and temperature stresses. Comparison Flexible pavements and rigid pavements can be compared on different parameters.

• Here only two parameters are considered: cost of construction and carbon footprints.
• Comparison Based on Cost A typical section of two-lane road with 7.0 m carriageway and 1.5 m wide shoulders on either side is considered.
• A length of one kilometer is considered for computation of the cost.
• Two types of pavements were designed for different types of soil subgrade (CBR ranging from 2 percent to 10 percent) and design traffic (1 msa to 150 msa), and the cost of each layer is computed using Dehradun PWD schedule of rates.

Therefore, a total of 90 pavements were designed and the costs of construction and maintenance were computed. The above ranges of soil and traffic values are assumed to cover almost all possible combinations of soil CBR and traffic loadings. Table 1 gives the costs of flexible pavements in million Rupees designed for different combinations of soil CBR and traffic conditions. Equation 1 shows the relation between the cost of flexible pavements and the soil CBR and traffic loading. Cost = -16.98 + 12.136 x CBR -0.3 + 15.476 x msa 0.10 -(1) (R 2 = 0.98) The cost of Rigid Pavement is also computed and the total cost of construction and maintenance for different soil and traffic conditions is shown in Table 2. Cost = 8.284 + 4.719 x cbr -0.9 + 20.83 x msa 0.15 -14 R 2 = 0.95 The points of equal cost on the CBR vs msa graph are plotted in Figure 1. Rigid pavements are found to be economical in the upper portion of the graph and flexible pavements are economical in the lower portion of the graph. Mathematically: if msa < 12.48 + 6.05 x CBR, flexible pavement will be economical; if msa > 12.48 + 6.05 x CBR, rigid pavement will be economical; if msa = 12.48 + 6.05 x CBR, both pavements will have the same cost. Comparison Based on Carbon Foot print Another comparison between flexible and rigid pavements could be in terms of carbon foot prints spent during construction. Road construction consumes energy in following five phases.

Energy consumed in manufacturing of construction materials (Embodied Energy) Energy consumed in the site preparation (Pre Construction) Energy used in actual construction of roads (induced energy) and transport of material (gray energy) Energy consumed during mainte- nance of road Energy consumed in demolition phase as well as recycling of their parts

Let us take a case study of pavement design for soil subgrade CBR of 8 % and traffic loading of 100 msa. The design of two pavements is shown in the chart 1. Chart 1: Note: WMM = Wet Mix Macadam; DBM= Dense Bituminous Macadam; BC = Bituminous Concrete; DLC = Dry Lean Concrete; PQC = Pavement Quality Concrete The total emissions during construction of one kilometer long road with flexible pavement and rigid pavement are given in Table 3.

Author could not get data on maintenance and demolition part of the road and therefore comparison is made based on first three operations only. The green house gas emissions during construction of two types of pavements are shown in Chart 1. All calculations are made for one kilometer road length with 7.0 m wide carriageway.

As may be seen, in case of rigid pavement, the embodied energy constitutes almost 96 percent of total emission while in case of flexible pavement energy consumed during construction is also substantial. However, if emission only during the construction is considered without considering the embodied emission of materials like cement and steel bar, then rigid pavement has lower emission during construction process.

1. Concluding Remarks Major highways constructed in the world are of bituminous surfacing.
2. For example, 86 percent of rural highways and 78 percent of urban roads in the U.S.
3. Are of flexible type.
4. Most of the runways in the world have flexible pavements, Autobahn in Germany is also with flexible pavement.

However, the choice of type of a pavement is governed by the type of traffic and soil conditions. In case of areas where soil subgrade is weak (like clay) and drainage conditions are also difficult to maintain at desired level of performance (like in urban areas or in situations where road passes through habitation), rigid pavement can be a good choice. PPCP Technology can help build roads of good quality, which are highly durable, can be built quickly, and do not require extensive maintenance. The construction industry is primarily concerned with two issues: construction quality control and the speed Read more, iROADS Asset Management System enables significant optimization of road maintenance costs while ensuring a well-maintained road network and road assets. India has the second largest road network in the world comprising national Read more, Rapid growth in industrial development and economy in last two decades has demanded upgradation of the existing road network in the country. Though there is a huge road network in the country, it is still inadequate to meet accessibility and mobility requirements Read more, Namrata Bichewar, Regional Manager – Maharashtra, Gabion Technologies India Pvt Ltd, discusses the company’s contribution in constructing green highways using Bio-Engineering Erosion Control methods and solutions. The government plans to construct 26 green expressways Read more, A Stone Matrix Asphalt (SMA) pavement laid at Parimal Underpass in Ahmedabad Municipal Corporation has completed 7 years. The underpass, which used to get submerged under almost 2m depth of water due to waterlogging in the monsoons every year Read more, Dr. Abhishek Mittal, Principal Scientist, CSIR-CRRI New Delhi, discusses the effects of changes in temperature due to climate change on pavements with respect to their material, design, construction, and maintenance. A long-term shift in temperature and weather Read more, Massive road development work for huge road network of the country’s national assets is essential for overall development of the country. However, major road development projects consume a huge quantity of soil and crushed aggregates. The consumption of these materials Read more, Following the launch of AEW’s road repair machine ‘Dr. Road’ by Shri Nitin Gadkari, Minister for Road Transport & Highways, Shatish Panchal, Director, AEW Group, informs that the company is geared up to promote the machine to State PWDs and CPWDs Read more, Evaluating the Quality of Asphalt Binders and Plant Produced Asphalt Mixes through Recovered Asphalt Testing and other Mix Properties, Amma Wakefield, MASc, PEng Canadian Regional Engineer Asphalt Institute, Paving-grade asphalt binders are specified based Read more, The Global Road Construction & Safety Conference 2022 will be held on 30th November 2022, at Hotel Taj Palace, New Delhi, in collaboration with CSIR- CRRI, Bitumen India Forum (BIF), National Highways Builders Federation (NHBF) Read more, The road construction industry in India is undergoing a paradigm shift: strong demand, higher investments, and the emergence of newer and more innovative technologies is giving a renewed focus on sustainable developments. These technologies include Read more, Subgrade makes the formation level of the road crust. The material specifications of subgrade material are therefore more demanding than the soil used in general fill or embankment. In some construction projects, it becomes difficult to get the required subgrade Read more, Atasi Das, Assistant Vice President, G R Infraprojects, explains the concept of the Perpetual Pavement in India’s expressway constructions and its practical implementation with due consideration of layers, materials, and thicknesses Read more, Dr. Rakesh Kumar, Senior Principal Scientist & Pankaj Goel, Senior Technical Officer, Rigid Pavements Division,CSIR-Central Road Research Institute (CRRI), New Delhi, give information on the Performance of Curing Compounds in Strengthening Read more, The construction and maintenance of roads with flexible pavements in very cold regions where annual temperatures range between +30oC to -35oC has got its own challenges. The bitumen in the asphalt layer becomes hard at such low temperatures Read more, The Bundelkhand site team achieved yet another feat on 15 Jan 2022 by completing 13 deck slabs of varying types in just 46 days. Therefore, it is a demonstration of exemplary display of overall project executing capabilities Read more, Er. Devjyoti Paul, Project Manager & Er. Harpreet Singh, Chief Project Manager, B&SEC, share the technical and construction features of three bowstring girder ROBs, recently constructed under Package I & III of Purvanchal Expressway in the state of Uttar Pradesh Read more, Use of Extruded Polystyrene Sheets (XPS) in the construction of the Zojila Approach Road has been especially effective as XPS is the most suitable, convenient, and cheaper solution for mitigating frost action on pavements, increasing the life of pavements Read more, The Indian road network is the second largest globally, with a length of around 63.86 lakh km. The outbreak of the virus towards end-FY20 had created panic globally, leading to the temporary suspension of economic activity Read more, Roads and Railways boost awards; tenders up marginally Overall tendering grew 5% YoY during H1FY22 Awarding activity grew at a 2-year CAGR of 22% in H1FY22 Infrastructure credit near all-time highs Read more,

What is rigid pavement and flexible pavement?

Basically, all hard surfaced pavement types can be categorized into two groups, flexible and rigid. Flexible pavements are those which are surfaced with bituminous (or asphalt ) materials. These can be either in the form of pavement surface treatments (such as a bituminous surface treatment (BST) generally found on lower volume roads) or, HMA surface courses (generally used on higher volume roads such as the Interstate highway network).

1. These types of pavements are called “flexible” since the total pavement structure “bends” or “deflects” due to traffic loads.
2. A flexible pavement structure is generally composed of several layers of materials which can accommodate this “flexing”.
3. On the other hand, rigid pavements are composed of a PCC surface course,

Such pavements are substantially “stiffer” than flexible pavements due to the high modulus of elasticity of the PCC material. Further, these pavements can have reinforcing steel, which is generally used to reduce or eliminate joints. Each of these pavement types distributes load over the subgrade in a different fashion.

• Rigid pavement, because of PCC’s high elastic modulus (stiffness), tends to distribute the load over a relatively wide area of subgrade (see Figure 1).
• The concrete slab itself supplies most of a rigid pavement ‘s structural capacity.
• Flexible pavement uses more flexible surface course and distributes loads over a smaller area.

It relies on a combination of layers for transmitting load to the subgrade. Figure 1. Flexible (left) and Rigid (right) Pavement Load Distribution Overall, it may be somewhat confusing as to why one pavement is used versus another. Basically, state highway agencies generally select pavement type either by policy, economics or both.

• Flexible pavements generally require some sort of maintenance or rehabilitation every 10 to 15 years.
• Rigid pavements, on the other hand, can often serve 20 to 40 years with little or no maintenance or rehabilitation.
• Thus, it should come as no surprise that rigid pavements are often used in urban, high traffic areas.

But, naturally, there are trade-offs. For example, when a flexible pavement requires major rehabilitation, the options are generally less expensive and quicker to perform than for rigid pavements.

What is the rigid pavement?

Rigid pavements are constructed of portland cement concrete slabs resting on a prepared subbase of granular material or directly on a granular subgrade. Load is transmitted through the slabs to the underlying subgrade by flexure of the slabs.

Is concrete flexible pavement?

Differences Between Concrete and Asphalt Pavement Differences Between Concrete and Asphalt Pavement Historically, pavements have been divided into two broad categories, rigid and flexible. These classical definitions, in some cases, are an over-simplification.

• However, the terms rigid and flexible provide a good description of how the pavements react to loads and the environment.
• The flexible pavement is an asphalt pavement.
• It generally consists of a relatively thin wearing surface of asphalt built over a base course and subbase course.
• Base and subbase courses are usually gravel or stone.

These layers rest upon a compacted subgrade (compacted soil). In contrast, rigid pavements are made up of portland cement concrete and may or may not have a base course between the pavement and subgrade. The essential difference between the two types of pavements, flexible and rigid, is the manner in which they distribute the load over the subgrade. Rigid pavement, because of concrete’s rigidity and stiffness, tends to distribute the load over a relatively wide area of subgrade.

The concrete slab itself supplies a major portion of a rigid pavement’s structural capacity. Flexible pavement, inherently built with weaker and less stiff material, does not spread loads as well as concrete. Therefore flexible pavements usually require more layers and greater thickness for optimally transmitting load to the subgrade.

The major factor considered in the design of rigid pavements is the structural strength of the concrete. For this reason, minor variations in subgrade strength have little influence upon the structural capacity of the pavement. The major factor considered in the design of flexible pavements is the combined strength of the layers.

1. One further practical distinction between concrete pavement and asphalt pavement is that concrete pavement provides opportunities to reinforce, texture, color and otherwise enhance a pavement, that is not possible with asphalt.
2. These opportunities allow concrete to be made exceedingly strong, long lasting, safe, quiet, and architecturally beautiful.

Concrete pavements on average outlast asphalt pavements by 10-15 years before needing rehabilitation. : Differences Between Concrete and Asphalt Pavement

Where are rigid pavements used?

37.8.1 Types of pavement – There are two main types of road construction. ” Rigid pavement,” such as concrete, can only be used on stable ground. “Flexible pavement,” such as bituminous materials, as described below, can be used on ground where some movement is expected. Figure 37.5 shows typical road construction types. Figure 37.5, Pavement Types

Which of the following is the type of road pavement?

Pavement Design Questions and Answers – Pavement Types This set of Pavement Design Multiple Choice Questions & Answers (MCQs) focuses on “Pavement Types”.1. A road pavement should have which of the following features? a) Yielding b) Non-yielding c) Undulation d) Deflection View Answer Answer: b Explanation: The road pavement must be non-yielding in order to withstand the heavy wheel load and allow the movement of traffic with the least resistance possible.

• There must be no undulations in the pavement to allow smooth riding and comfort to passengers.2.
• Pavement has a concrete slab as the topmost layer.
• A) Fixed b) Flexible c) Portable d) Rigid View Answer Answer: d Explanation: Rigid pavement is the one that has a concrete slab as the topmost layer.
• It possesses flexural strength and hence it is named so.

Flexible pavement is the one that has bituminous material as the topmost layer and it has negligible flexural strength.3. In what shape is the compressive strength distributed in a flexible pavement? a) Truncated cone b) Rectangle c) Circle d) Cone View Answer Answer: a Explanation: The compressive strength is distributed to a wider area in a truncated cone shape.

The stress is highest at top layers and it keeps decreasing as it proceeds to the bottom layers. This helps in preserving the bottom layer from the stresses as well as weathering effects for a longer period of time. Note: Join free Sanfoundry classes at or 4. Which of the below is not an example of rigid pavement? a) Lean cement concrete b) Jointed plain concrete c) Continuous reinforced concrete d) Pre-stressed concrete View Answer Answer: a Explanation: Lean cement concrete is a type of semi-rigid pavement.

A semi-rigid pavement makes use of bonded materials like pozzolanic concrete, lean cement concrete, soil-cement. All other options are types of rigid pavement. View Answer Answer: c Explanation: The layer is termed as binder course as it forms a connection between the base and the surface course. The binder course usually consists of dense graded bitumen. The sub-base and base course are granular. The surface course is also termed as weathering course and the sub-base serves as the drainage layer.6.

1. After how long can the flexible pavement be opened to the public after its construction? a) 24 hours b) 24 days c) 28 hours d) 28 days View Answer Answer: a Explanation: Flexible pavements consist of bituminous topping and the curing period is just 25 hours.
2. Whereas, a rigid pavement consists of concrete topping and thus it requires a curing period of 28 days for attaining its full strength.7.

_ pavement consists of both flexible and rigid layers. a) Combined b) Semi-flexible c) Composite d) Semi-rigid View Answer Answer: c Explanation: Composite pavement is named because it consists of layers of both pavement types – flexible and rigid. It is generally designed as a flexible pavement and modifications for thickness are made based on rigid pavement requirements.8.

1. Interlocking cement concrete block pavement can be used in areas of heavy traffic.
2. A) True b) False View Answer Answer: a Explanation: Interlocking cement concrete block pavement has a wide range of applications.
3. It can be used in areas of non-traffic like footpaths, light traffic like car parks, medium traffic like small market roads and heavy traffic areas like heavy-duty roads on expansive soils and airport pavement.9.

Which of the below is not a primary function of a pavement? a) Waterproofing b) Smooth surface c) Skid resistance d) Reduce traffic View Answer Answer: d Explanation: The presence of pavement does not ensure traffic reduction, there are specific measures and modifications to be done to the pavement.

• Waterproofing is necessary to avoid waterlogging and seeping into the subgrade.
• It is necessary to provide a smooth surface with skid resistance to allow the vehicle to travel at the desired speed and comfort.10.
• In which of the below types of pavement can joints be eliminated completely? a) Continuous reinforced concrete pavement b) Jointed reinforced concrete pavement c) Pre-stressed concrete pavement d) Jointed plain concrete pavement View Answer Answer: a Explanation: In continuous reinforced concrete pavement, reinforcement is provided throughout and it helps in the elimination of joints.

It is similar to that of a continuous slab. All other types have joints and dowel bars are used to interlock them.11. Which of the below IRC codes gives the guidelines for use of interlocking concrete block pavement? a) IRC SP: 49-1998 b) IRC SP: 11-1988 c) IRC 50-1973 d) IRC SP: 63-2004 View Answer Answer: d Explanation: IRC SP: 63-2004 is the code used for guidelines on the usage of interlocking concrete block pavement.

HOT MIX ASPHALT

UNBOUND AGGREGATE BASE

CEMENT TREATED BASE

SUBGRADE

a) Composite pavement b) Mixed pavement c) Inverted pavement d) Combined pavement View Answer Answer: c Explanation: Inverted pavement consists of thicker and stiffer supporting layers than the top layers. The base used here is cement treated and a thin asphalt/bitumen layer is provided on top.

1. It is found to be better performing than the conventional pavement.
2. Composite pavement has the same layer structure as conventional pavements, but it consists of both flexible and rigid pavement considerations.13.
3. Rigid pavements are stiffer than flexible pavements due to _ a) Low modulus of rigidity b) Low modulus of elasticity c) High modulus of rigidity d) High modulus of elasticity View Answer Answer: d Explanation: Modulus of elasticity gives a measure of resistance to elastic deformation.

Rigid pavement is stiffer than flexible pavement because it has a high modulus of elasticity. Modulus of rigidity relates shear stress and shear strain and that is not applicable here.14. Perpetual pavements can last longer than 50 years without any maintenance.

• A) True b) False View Answer Answer: a Explanation: Perpetual pavements consist of thick layers of asphalt that are able to support and transfer heavy loads, resist weathering effects and thus last longer than 50 years without the need for maintenance.
• An example is a section of road in Oklahoma that was built in 1967 and is still functioning in excellent condition.15.

Kerb is provided at the edge of interlocking cement concrete block pavement to _ a) Provide aesthetic appearance b) Provide lateral confinement c) Aid in drainage d) Mark end of the pavement View Answer Answer: b Explanation: The paver blocks are individual units placed together and their joints are filled with joint filling sand and vibrated to ensure interlocking.

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Which of the following is a classification of pavement Mcq?

1. Which of the following is a classification of pavements? Explanation: Pavements are classified in to Flexible, rigid and semi-flexible, based on distributing loads.

What are the classification of roads?

Classification of Highways | Current Affairs

• What is the issue?
• Following the Supreme Court’s order banning sale of liquor within 500 metres of any National/State Highway, some states started to circumvent the court’s order.
• How are roads classified in India?

• The Nagpur Plan divides roads into 4 main categories: National Highways, State Highways, District Roads and Village roads.
• Expressways were added as an additional category.

• National Highways – Roads that are required for strategic movement, those that reduce the travel time substantially, and those that open up backward areas and help economic growth, are also classified as National Highways.
• They connect all major ports, state capitals, large industrial and tourist centres, and foreign highways.
• State Highways – They are the arterial roads of a state that connect to National Highways, district headquarters and important cities and are also linked to district roads.
• Major District Roads – They connect areas of production, main markets and the State and National Highways crossing the state.
• Village Roads connect villages to each other or to the nearest District Roads.

Who decides the requirements for classification?

• Indian Roads Congress (IRC) is a semi-official body that was set up by the government in 1934 and registered as a society in 1937.
• It decides the minimum requirements for roads, keeping in mind geography, speed, volume of traffic and safety.
• It is also the apex body of road engineers in the country and regularly updates the technical requirements such as width, sight distance and other related parameters.

What is the length of India’s road network?

At the end of 2015-16, India had a total kilometres of

1. NH and Expressways – 1,00,475
2. State Highways – 1,48,256 km
3. Other Roads – 49,83,589 km

• Roads carry about 65% of India’s freight traffic and 80% of its passenger traffic.
• NH constitutes approximately 2% of the road network and carries 40% of the country’s total road traffic.

How are National Highways numbered?

• According to the new system, all east-west highways have odd numbers.
• All north-south highways have even numbers.
• On odd-numbered highways, the number increases from north to south.
• e.g NH from Jodhpur to Kanpur will have a smaller number than a NH from Mumbai to Chennai.
• Similarly the numbers increase from east to west.
• e.g NH from Kolkata to Chennai will have a smaller number than a NH from Delhi to Mumbai.

Who is responsible for the maintenance?

• Under the National Highways Act, 1956, NH became the responsibility of the central government.
• National Highways Authority of India (NHAI) was created to look after National Highways.
• The Public Works Departments of states are mandated to look after State Highways.
• In Union Territories, the UT government is responsible for State Highways.

How do states circumvent the Supreme Court’s order?

• Central government the exclusive right to notify/denotify any road in the country as a National Highway and add it to the list of National Highways annexed to the Act.
• State governments can send proposals to the central government to upgrade roads to National Highways.
• After the Union Cabinet approves an upgradation, National Highways Act, 1956, has to be amended to include it in the NH.
• States cannot upgrade State Highways to National Highways or vice versa.
• However they have the right to tag State Highways as District Roads.
• This has been done by some states to circumvent the Supreme Court’s order.
• In such cases, liquor can be bought or consumed near these Highway-turned-District Roads.

Source: Indian Express : Classification of Highways | Current Affairs

What are the main classification of roads?

State Highways (SH) Major District Highways (MDR) Other District Roads (ODR) Village Roads (VR)

What are the 3 main classifications of roadways?

Roadways are classified by how they function within a transportation system. Functional classification divides these roadways into three categories: arterial, collector, and local roads. Typically, travelers will use a combination of all three types of roadways for their trips.

How many types of road pavements are there?

Types of Pavements – There are two types of pavements based on design considerations i.e. flexible pavement and rigid pavement. Difference between flexible and rigid pavements is based on the manner in which the loads are distributed to the subgrade. Before we differentiate between flexible pavements and rigid pavements, it is better to first know about them.

What is road and its types?

Road | Definition, History, Types, & Facts road, traveled way on which people, animals, or wheeled vehicles move. In modern usage the term road describes a rural, lesser traveled way, while the word street denotes an urban roadway. refers to a major rural traveled way; more recently it has been used for a road, in either a rural or urban area, where points of entrance and exit for traffic are limited and controlled.

1. The most ancient name for these arteries of travel seems to be the of the modern way,
2. Way stems from the Middle English wey, which in turn branches from the Latin veho (“I carry”), derived from the Sanskrit vah (“carry,” “go,” or “move”).
3. The word highway goes back to the elevated Roman roads that had a mound or hill formed by earth from the side ditches thrown toward the centre, thus high way,

The word street originates with the Latin strata (initially, “paved”) and later strata via (“a way paved with stones”). Street was used by the Anglo-Saxons for all the roads that they inherited from the Romans. By the Middle Ages, constructed roads were to be found only in the towns, and so street took on its modern limited application to town roads.

The more recent word road, from the Old English word rád (“to ride”) and the Middle English rode or rade (“a mounted journey”), is now used to indicate all vehicular ways. Modern roads can be classified by type or function. The basic type is the conventional undivided two-way road. Beyond this are divided roads, expressways (divided roads with most side access controlled and some minor at-grade intersections), and freeways (expressways with side access fully controlled and no at-grade intersections).

An access-controlled road with direct user charges is known as a tollway. In the United Kingdom freeways and expressways are referred to as motorways. Functional road types are local streets, which serve only properties and do not carry through traffic; collector, distributor, and feeder roads, which carry only through traffic from their own area; arterial roads, which carry through traffic from adjacent areas and are the major roads within a region or population centre; and highways, which are the major roads between regions or population centres.

• The first half of this article traces the history of roads from earliest times to the present, exploring the factors that have influenced their development and suggesting that in many ways roads have directly reflected the conditions and attitudes of their times.
• The road is thus one of the oldest continuous and traceable for civilization and society.

The second half of the article explains the factors behind the design,, and operation of a modern road. It is shown that a road must interact closely and carefully with the terrain and through which it passes, with changing vehicle, with information technologies, and with the various abilities, deficiencies, and frailties of the individual driver.

The first roads were paths made by animals and later adapted by humans. The earliest records of such paths have been found around some springs near Jericho and date from about 6000 bce, The first indications of constructed roads date from about 4000 bce and consist of stone-paved streets at in modern-day Iraq and timber roads preserved in a swamp in, England.

During the the availability of metal tools made the construction of stone paving more, At the same time, demand for paved roads rose with the use of wheeled vehicles, which were well established by 2000 bce, Get a Britannica Premium subscription and gain access to exclusive content.

1. At about this time the Minoans on the island of built a 30-mile (50-km) road from Gortyna on the south coast over the mountains at an elevation of about 4,300 feet (1,300 metres) to Knossos on the north coast.
2. Constructed of layers of stone, the roadway took account of the necessity of drainage by a crown throughout its length and even gutters along certain sections.

The pavement, which was about 12 feet (360 cm) wide, consisted of sandstone bound by a clay-gypsum mortar. The surface of the central portion consisted of two rows of basalt slabs 2 inches (50 mm) thick. The centre of the roadway seems to have been used for foot traffic and the edges for animals and carts.

It is the oldest existing paved road. The earliest long-distance road was a 1,500-mile route between the and the, It came into some use about 3500 bce, but it was operated in an organized way only from about 1200 bce by the Assyrians, who used it to join Susa, near the Persian Gulf, to the Mediterranean ports of Smyrna (İzmir) and Ephesus.

More a track than a constructed road, the route was duplicated between 550 and 486 bce by the great Persian kings and in their famous Royal Road. Like its predecessor, the began at Susa, wound northwestward to Arbela, and thence proceeded westward through Nineveh to Harran, a major road junction and caravan centre.

• The main road then continued to twin termini at Smyrna and Ephesus.
• The Greek historian, writing about 475 bce, put the time for the journey from Susa to Ephesus at 93 days, although royal riders the route in 20 days.
• In about 615 bce the connected the city’s temples to the royal palaces with the, a major road in which burned bricks and carefully shaped stones were laid in bituminous mortar.

Herodotus credits the Egyptians with building their first roads to provide a solid track upon which to haul the immense limestone blocks used in the pyramids, and archaeological evidence indicates that such road building took place southwest of Cairo between 2600 and 2200 bce,

The wheel arrived in Egypt at the relatively late date of about 1600 bce, There is little evidence of street surfacing in ancient Egyptian towns, though there is evidence of the use of paved processional roads leading to the temples. The ancient travel routes of Egypt ran from Thebes and Coptos on the central Nile east to the and from Memphis (Cairo) across the to,

The early Greeks depended primarily on sea travel. There is evidence of the building of special roads for religious purposes and transport about 800 bce, but there is little evidence of substantial road building for travel and transport prior to the Roman system.

1. The Greeks did build a few ceremonial, or “sacred,” roads, paved with shaped stone and containing wheel about 55 inches (140 cm) apart.
2. During the 2nd millennium bce, trade ways developed in Europe.
3. One route, for example, ran between Italy and Spain via Marseille and nearby Heraclea, close to present-day Avignon, France.

Such ways were used for the movement of flints from Denmark, freestone from Belgium, salt from Austria, lead and tin from England, and amber from northern Europe. By about 1500 bce many of the ways in eastern and central Europe had linked together into an extensive trading network known as the Amber Routes.

Four routes have been identified, the first from modern Hamburg, Germany, southwestward by dual routes through Cologne and Frankfurt to Lyon and Marseille. The second also passed from Hamburg south to Passau on the Danube and then through the to Venice. The third began at Samland on the East Prussian coast (where amber is still found), crossed the at Thorn, and thence continued southeastward through the Moravian Gate to Aquileia on the Adriatic.

The fourth, the Baltic-Pontus road, followed the main eastern rivers, the Vistula, Saw, Sereth, Prut, Bug, and Dnieper. While the Amber Routes were not roads in the modern sense, they were improved at river crossings, over mountain passes, and across wet and swampy areas.

A few remnants of these roads survive today. They were constructed by laying two or three strings of in the direction of the road on a bed of branches and up to 20 feet (6 metres) wide. This layer was then covered with a layer of transverse logs 9 to 12 feet in length laid side by side. In the best log roads, every fifth or sixth log was fastened to the underlying subsoil with pegs.

There is evidence that the older log roads were built prior to 1500 bce, They were maintained in a level state by being covered with sand and gravel or sod. In addition, the Romans used side ditches to reduce the moisture content and increase the, The greatest systematic road builders of the ancient world were the Romans, who were very of the military, economic, and administrative advantages of a good road system.

The Romans drew their expertise mainly from the —particularly in cement technology and street paving—though they probably also learned skills from the Greeks (masonry), Cretans, Carthaginians (pavement structure), Phoenicians, and Egyptians (surveying). made from cement was a major development that permitted many of Rome’s construction advances.

The Romans began their road-making task in 334 bce and by the peak of the empire had built nearly 53,000 miles of road connecting their capital with the frontiers of their far-flung empire. Twenty-nine great military roads, the viae militares, radiated from Rome.

The most famous of these was the, Begun in 312 bce, this road eventually followed the Mediterranean coast south to Capua and then turned eastward to Beneventum, where it divided into two branches, both reaching Brundisium (Brindisi). From Brundisium the Appian Way traversed the Adriatic coast to Hydruntum, a total of 410 miles from Rome.

The typical Roman road was bold in and construction. Where possible, it was built in a straight line from one sighting point to the next, regardless of obstacles, and was carried over marshes, lakes, ravines, and mountains. In its highest stage of development, it was constructed by excavating parallel trenches about 40 feet apart to provide longitudinal —a hallmark of Roman road engineering.

The foundation was then raised about three feet above ground level, employing material taken from the drains and from the adjacent cleared ground. As the importance of the road increased, this embankment was progressively covered with a light bedding of sand or mortar on which four main courses were constructed: (1) the statumen layer 10 to 24 inches (250 to 600 mm) thick, composed of stones at least 2 inches in size, (2) the rudus, a 9-inch-thick layer of concrete made from stones under 2 inches in size, (3) the nucleus layer, about 12 inches thick, using concrete made from small gravel and coarse sand, and, for very important roads, (4) the summum dorsum, a wearing surface of large stone slabs at least 6 inches deep.

The total thickness thus varied from 3 to 6 feet. The width of the Appian Way in its ultimate development was 35 feet. The two-way, heavily central carriageway was 15 feet wide. On each side it was flanked by curbs 2 feet wide and 18 inches high and paralleled by one-way side lanes 7 feet wide.

This massive Roman road section, adopted about 300 bce, set the standard of practice for the next 2,000 years. The public transport of the Roman Empire was divided into two classes: (1) cursus rapidi, the express service, and (2) agnarie, the freight service. In addition, there was an enormous amount of travel by private individuals.

The two most widely used vehicles were the two-wheeled drawn by two or four horses and its companion, the cart used in rural areas. A four-wheeled raeda in its passenger version corresponded to the stagecoaches of a later period and in its version to the freight wagons.

Fast freight raedae were drawn by 8 horses in summer and 10 in winter and, by law, could not haul in excess of 750 pounds (340 kg). Speed of travel ranged from a low of about 15 miles per day for freight vehicles to 75 miles per day by speedy post drivers. The in Sindh, Balochistan, and the Punjab probably flourished in the period 3250–2750 bce,

Excavations indicate that the cities of this civilization paved their major streets with burned bricks cemented with bitumen. Great attention was devoted to, The houses had drainpipes that carried the water to a street drain in the centre of the street, two to four feet deep and covered with slabs or bricks.

Evidence from archaeological and historical sources indicates that by 75 ce several methods of road construction were known in India. These included the brick pavement, the stone slab pavement, a kind of concrete as a foundation course or as an actual road surface, and the principles of grouting (filling crevices) with gypsum, lime, or bituminous mortar.

Street paving seems to have been common in the towns in India at the beginning of the Common Era, and the principles of drainage were well known. The of the roadway and the use of ditches and gutters were common in the towns. Northern and western India in the period 300 to 150 bce had a network of well-built roads.

• The rulers of the (4th century bce ), which stretched from the to the and from the Himalayas to the, generally recognized that the unity of a great empire depended on the quality of its roads.
• The Great Royal Road of the Mauryans began at the Himalayan border, ran through Taxila (near modern Rawalpindi, Pakistan), crossed the five streams of the Punjab, proceeded by way of Jumna to Prayag (now Prayagraj, India), and continued to the mouth of the,

A “Ministry of Public Works” was responsible for construction, marking, and maintenance of the roads and rest houses and for the smooth running of ferries. China had a road system that paralleled the Persian Royal Road and the Roman road network in time and purpose.

Its major development began under Emperor about 220 bce, Many of the roads were wide, surfaced with stone, and lined with trees; steep mountains were by stone-paved stairways with broad treads and low steps. By 700 ce the network had grown to some 25,000 miles (about 40,000 km). Traces of a key route near Xi’an are still visible.

The trade route from China to Asia Minor and India, known as the Silk Road, had been in existence for 1,400 years at the time of ‘s travels (c.1270–90 ce ). It came into partial existence about 300 bce, when it was used to bring jade from Khotan (modern Hotan, China) to China.

1. By 200 bce it was linked to the West, and by 100 bce it was carrying active trade between the two civilizations.
2. At its zenith in 200 ce this road and its western connections over the Roman system the longest road on Earth.
3. In Asia the road passed through Samarkand to the region of Fergana, where, near the city of Osh, a stone tower marked the symbolic watershed between East and West.

From Fergana the road traversed the valley between the and through Kashgar, where it divided and skirted both sides of the to join again at Yuanquan. The road then wound eastward to Jiayuguan (Suzhou), where it passed through the westernmost gateway (the Jade Gate, or Yumen) of the,

It then went southeast on the Imperial Highway to Xi’an and eastward to Shanghai on the, From Kashgar, trade routes to the south passed over the mountains to the great trading centre of Bactria and to northern Kashmir. At the zenith of the Roman Empire, overland trade joined the of Europe,, Asia Minor, China, and India.

But the system of road transport was dependent on the Roman, Chinese, and Mauryan empires, and, as these great empires declined in the early Christian era, the trade routes became routes of invasion. Except in the, road networks fell into centuries of disrepair.

1. Transport relied on pack trains, which could negotiate the badly maintained roads and to carry the reduced stream of commerce.
2. The first signs of a road revival came during the reign of Charlemagne late in the 8th century.
3. In the 9th century the established an extensive street network in,,
4. The operated the Varangian Road, a major trade route linking the Baltic and the via Russia.

Further road revival was aided first by the need to service the regular round of trade fairs and then, in the 11th century, by a centralization of power and an increase in religious fervour. Eventually a commercial revival set in. By the 12th century old cities were and new ones were being built, especially in western Europe.

Street paving became a reputable artisan activity, and by the 15th century well-maintained roads bringing food to the cities from their hinterlands were of critical importance. At the same time, wheeled vehicles increased in number and quality. There was an awakened interest in better overland travel, better protection of merchants and other travelers, and the improvement of roads.

Public funds, chiefly derived from tolls, were committed to road upkeep. The corvée, or road-labour tax, made an even more substantial contribution. Long-distance overland commerce increased rapidly and included a restoration of the route between Europe and China through that Marco Polo traveled in the late 13th century.

Across the Atlantic, the period the rise of another notable road-building empire, that of the Incas. The Inca road system extended from Quito, Ecuador, through Cuzco, Peru, and as far south as Santiago, Chile. It included two parallel roadways, one along the coast about 2,250 miles in length, the other following the Andes about 3,400 miles in length with a number of cross connections.

Concrete Road VS Asphalt Road

At its zenith, when the Spaniards arrived early in the 16th century, a network of some 14,000 miles of road served an area of about 750,000 square miles (1,940,000 square km) in which lived nearly 10 million people. The network was praised by 16th-century explorers as superior to that in contemporary Europe.

1. The route was remarkable.
2. The roadway was 25 feet wide and traversed the loftiest ranges.
3. It included galleries cut into solid rock and retaining walls built up for hundreds of feet to support the roadway.
4. Ravines and chasms were filled with solid masonry, suspension bridges with wool or fibre cables crossed the wider mountain streams, and stone surfacing was used in difficult areas.

The steeper gradients were surmounted by steps cut in the rocks. Traffic consisted entirely of pack animals (llamas) and people on foot; the Inca lacked the wheel. Yet they operated a swift foot courier system and a visual signaling system along the roadway from watchtower to watchtower.

• In, gradual technological improvements in the 17th and 18th centuries saw increased commercial travel, improved vehicles, and the breeding of better horses.
• These factors created an incessant demand for better roads, and supply and invention both rose to meet that demand.
• In 1585 the Italian engineer Guido Toglietta wrote a thoughtful on a pavement system using broken stone that represented a marked advance on the heavy Roman style.

In 1607 Thomas Procter published the first English-language book on roads. The first highway school in Europe, the School of Bridges and Highways, was founded in Paris in 1747. Late in the 18th century the Scottish political economist, in discussing conditions in England, wrote, Good roads, canals, and navigable rivers, by diminishing the expense of carriage, put the remote parts of the country more nearly upon a level with those in the neighbourhood of a town.

1. They are upon that account the greatest of all improvements.
2. Up to this time roads had been built, with minor modifications, to the heavy Roman, but in the last half of the 18th century the fathers of modern road building and road maintenance appeared in and Britain.
3. In France,, an engineer from an engineering family, became in 1764 engineer of bridges and roads at Limoges and in 1775 inspector general of roads and bridges for France.

In that year he developed an entirely new type of relatively light road surface, based on the theory that the natural formation, rather than the pavement, should support the load. His standard cross section (shown in the figure, top) was 18 feet wide and consisted of an eight-inch-thick course of uniform foundation stones laid edgewise on the natural formation and covered by a two-inch layer of walnut-sized broken stone.

This second layer was topped with a one-inch layer of smaller gravel or broken stone. In order to maintain surface levels, Trésaguet’s pavement was placed in an excavated trench—a technique that made drainage a difficult problem., born of poor parents in Dumfriesshire, Scotland, in 1757, was apprenticed to a stone mason.

Intelligent and ambitious, Telford progressed to designing bridges and building roads. He placed great on two features: (1) maintaining a level roadway with a maximum gradient of 1 in 30 and (2) building a stone surface capable of carrying the heaviest anticipated loads.

His roadways were 18 feet wide and built in three courses: (1) a lower layer, seven inches thick, consisting of good-quality foundation stone carefully placed by hand (this was known as the Telford base), (2) a middle layer, also seven inches thick, consisting of broken stone of two-inch maximum size, and (3) a top layer of gravel or broken stone up to one inch thick.

( See figure, middle.) The greatest advance came from, born in 1756 at Ayr in Scotland. McAdam began his road-building career in 1787 but reached major heights after 1804, when he was appointed general surveyor for Bristol, then the most important port city in,

The roads leading to Bristol were in poor condition, and in 1816 McAdam took control of the Bristol Turnpike. There he showed that traffic could be supported by a relatively thin layer of small, single-sized, angular pieces of broken stone placed and compacted on a well-drained natural formation and covered by an impermeable surface of smaller stones.

He had no use for the masonry constructions of his predecessors and contemporaries. was essential to the success of McAdam’s method, and he required the pavement to be elevated above the surrounding surface. The structural layer of broken stone (as shown in the figure, bottom) was eight inches thick and used stone of two to three inches maximum size laid in layers and compacted by traffic—a process adequate for the traffic of the time.

1. The top layer was two inches thick, using three-fourths- to one-inch stone to fill surface voids between the large stones.
2. Continuing maintenance was essential.
3. Although McAdam drew on the successes and failures of others, his total structural reliance on broken stone represented the largest shift in the history of road pavements.

The principles of the ” ” road are still used today. McAdam’s success was also due to his efficient administration and his strong view that road managers needed skill and motivation. The first engineered and planned road in the was the Lancaster Turnpike, a privately constructed toll road built between 1793 and 1795.

Connecting Philadelphia and Lancaster in Pennsylvania, its 62-mile length had a maximum grade of 7 percent and was surfaced with broken stone and gravel in a manner initially uninfluenced by the work of Telford and McAdam. However, pavement failures in 1796 led to the introduction of some of the new European methods.

The Cumberland Road, also known as the National, was an even more notable road-building feat. It had been advocated by both and to aid western expansion and national unity. Work commenced in 1811, and the road opened for traffic between Cumberland, Maryland, and Wheeling,, in 1818.

By 1838 it extended to Springfield, Ohio, and part of the way to Vandalia, Illinois. Specification requirements called for a 66-foot right-of-way completely cleared. The roadway was to be covered 20 feet in width with stone 18 inches deep at the centre and 12 inches deep at the edge. The upper six inches were to consist of broken stone of three-inch maximum size and the lower stratum of stone of seven-inch maximum size.

The road was constructed by the federal government, much of the finance being raised by land sales. Although maintenance was funded by and federal appropriations, the road surface began to deteriorate in the 1820s. Federal funding ceased in 1838, and in 1841 the project was abandoned at Vandalia for political and practical reasons.

Beginning in the 1840s, the rapid development of railroads brought the construction of lightweight Trésaguet-McAdam roads to a virtual halt. For the next 60 years, road improvements were essentially confined to city streets or to feeder roads to railheads. Other rural roads became impassable in wet weather.

The initial stimulus for a renewal of road building came not from the, whose impact was scarcely felt before 1900, but from the, for whose benefit road improvement began in many countries during the 1880s and ’90s. Nevertheless, while the requirements of the lightweight, low-speed bicycle were satisfied by the old “macadamized” surfaces, the automobile began to raise its own seemingly demands as the world entered the 20th century.

• When urban street paving became widespread in the latter half of the 19th century, the common paving materials were hoof-sized blocks, similarly sized wooden blocks, bricks, McAdam’s broken stone, and occasionally asphalt and concrete.
• McAdam’s broken stone provided the cheapest pavement, but its unbound surface was difficult to maintain and was usually either slimy or dusty as a consequence of water, weather, and amounts of horse excrement.

Thus, roads at the turn of the 20th century were largely inadequate for the demands about to be placed on them by the automobile and truck. As vehicle speeds increased rapidly, the available friction between road and tire became critical for accelerating, braking, and cornering.

• In addition, numerous pavement failures made it obvious that much stronger and tougher materials were required.
• The result was an ongoing search for a better pavement.
• And both offered promise.
• Asphalt is a mixture of bitumen and stone, and concrete is a mixture of cement and stone.
• Asphalt footpaths were first laid in in 1810, but the method was not perfected until after 1835.

The first road use of asphalt occurred in 1824, when asphalt blocks were placed on the in Paris, but the first successful major application was made in 1858 on the nearby rue Saint-Honoré. The first successful concrete pavement was built in Inverness, Scotland, in 1865.

Neither technology, however, advanced far without the pressures of the car, and they both required the availability of powerful stone-crushing, mixing, and spreading equipment. The for the development of modern road asphalt came from the, which had few deposits of natural bitumen to draw upon and where engineers were therefore forced to study the principles behind the behaviour of this material.

The first steps came in the 1860s, with the work of Belgian immigrant Edward de Smedt at in New York City. De Smedt conducted his first tests in New Jersey in 1870 and by 1872 was producing the equivalent of a modern “well-graded” maximum-density asphalt.

1. The first applications were in Park and on Fifth Avenue in New York City in 1872.
2. De Smedt went to, D.C., in 1876 as part of President ‘s desire to make that town “a Capital City worthy of a great Nation.” Grant had appointed a commission to oversee road making, and it conducted its first trials on in 1877.

Sixty percent of the trials used de Smedt’s new product and were great successes. In 1887 de Smedt was followed as inspector of asphalts and cements by Clifford Richardson, who set about the task of codifying the specifications for asphalt mixes. Richardson basically developed two forms of asphalt: asphaltic concrete, which was strong and stiff and thus provided structural strength; and hot-rolled asphalt, which contained more bitumen and thus produced a far smoother and better surface for the car and bicycle.

1. One of the great convenient coincidences of asphalt development was that the automobile ran on, which at that time was simply a of the distillation of kerosene from petroleum.
2. Another by-product was bitumen.
3. Until that time, most manufacturers had used (a by-product of the making of gas from coal) as the binder for road asphalt.

As the demand for automobile fuel increased, however, so did the availability of bitumen and, hence, of good asphalt designed to the standards of de Smedt and Richardson. This gave American road builders a major advantage over their European counterparts, who were still wedded to the virtues of the various natural asphalts, such as those from Neuchâtel, Switzerland, and the island of Trinidad.

Richardson published a standard textbook on asphalt paving in 1905, and the practice did not change greatly thereafter. The biggest change was in the machinery available to produce, place, and finish the material rather than in the product itself. Toward the end of the century, there were major movements toward the use of recycled asphalt, chemical modifiers for improving bitumen properties, and small fibres for improving crack resistance.

In addition, developments in testing and structural analysis made it possible to design an asphalt pavement as a structural composite. The first modern concrete roads were produced by Joseph Mitchell, a follower of Telford, who conducted three successful trials in England and Scotland in 1865–66.

1. Like asphalt technology, concrete road building was largely developed by the turn of the 20th century and was restricted more by the available machinery than by the material.
2. Problems were also encountered in producing a surface that could match the performance of the surface produced almost accidentally by hot-rolled asphalt.

For the following century the two materials remained in intense competition, both offering a similar product at a similar cost, and there was little evidence that one would move far ahead of the other as they continued on their paths of gradual improvement.

(The principles of modern pavement design are described below in,) Through the, responsibility for financing and building roads and highways has been both a local and a national responsibility in the nations of the world. It is notable that this responsibility has changed along with political attitudes toward road building and has not rested easily with any party.

Many roads initially were built to provide rulers with a means of conquest, control, and taxation; in periods of peace, the same rulers usually tried to pass the maintenance responsibilities on to local authorities, adjoining landowners, or the travelers who used the road.

• Local authorities and landowners usually fulfilled their responsibilities via the, in which people were required to donate their labour to road work.
• Corvée was always unpopular and unproductive, but it was nevertheless more effective than attempts at direct taxation.
• The last option, charging the traveler, gave rise to the road, a system that blossomed with the,

Private turnpike trusts dominated British road building and maintenance throughout the 19th century, eventually covering 15 percent of the entire network. In the United States many roads were constructed in the first half of the 19th century under charters granted by the states.

1. Thus, through the 19th century most road building was administered and financed on a local basis.
2. Road building remained entirely local despite clear evidence that local responsibility was not providing adequate roads.
3. The national edged into the picture only through increased pressure from the cyclists, climaxed by the establishment in 1909 of a national Road Board authorized to construct and maintain new roads and to make advances to highway authorities to build new or improve old roads.

Except for the National Pike, early highway building in the was also carried on by local government. made a number of land grants for the opening of wagon roads but exercised no control over the expenditure of funds—with the result that, as in Britain, little road building was accomplished.

1. In 1891 enacted a law providing for aid to the counties and established procedures for raising money at the township and county levels for road building.
2. In 1893 established the first state highway commission.
3. By 1913 most of the states had adopted similar legislation, and by 1920 all states had their own road organization.

However, there was little coordination among the states. National funding began in 1912 with the Post Office Appropriation Act, and the Federal Aid Road Act of 1916 established federal aid for highways as a national policy. The Bureau of Public Roads, established in the Department of Agriculture in 1893 to make “inquiries with regard to road management,” was given responsibility for the program, and an apportionment formula based on area, population, and mileage of post roads in each state was adopted.

• Funds were for construction costs, with the states being required to bear all maintenance costs.
• The location and selection of roads to be improved was left to the states, an arrangement that had some shortcomings.
• Since 1892 a national had lobbied for a system of national roads joining the major population centres and contributing to the national economy.

This point of view was recognized by the Federal Aid Highway Act of 1921, which required each state to a system of state highways not to exceed 7 percent of the total highway mileage in each state. Federal-aid funding was limited to this system, which was not to exceed three-sevenths of total highway mileage.

Bureau of Public Roads approval of the system was required, and federal aid was limited to 50 percent of the estimated cost. The achievement of such a system in the automobile age required a new form of road. This grew from the parkway, which had many historical precedents but was introduced in its modern form in 1858 with the work of the landscape architects and Calvert Vaux for in,

The was given further prominence by William Niles White of New York as a part of the Bronx River protection program of New York City and Westchester County. The 15-mile, four-lane single carriageway known as the was built between 1916 and 1925. Protected on both sides by broad bands of parkland that limited access, the highway was located and designed so as to cause minimum disturbance to the landscape.

• Its use was restricted to passenger cars, and at-grade intersections were avoided.
• The success of the concept led to the creation of the Westchester County parkway system and the Long Island State Park Commission.
• More parkways were built in the New York area, including the (1934–40), which continued the Westchester Parkway System across Connecticut as a toll road providing divided roadways and limited access.

The success of the parkway system led to the introduction of the freeway, which is a divided highway with no conflicting traffic movements and no access from adjoining properties. In between 1913 and 1921 a group called AVUS had built 10 km (6 miles) of parkway through the Grunewald park in Berlin.

Their successful experience led to the world’s first full freeway being built from Cologne to Bonn between 1929 and 1932. In 1933 began construction of an freeway network known as the, or “national motor roads,” beginning with the Frankfurt-Darmstadt-Mannheim-Heidelberg, One purpose of the program was to unemployment, but the roads also appealed to German and had a strong militaristic intent.

The entire system included three north-south routes and three east-west routes. The highway provided separate 7.5-metre (25-foot) carriageways divided by a median strip of 5 metres (16 feet). The roads were designed for large traffic volumes and speeds in excess of 150 km (90 miles) per hour, bypassing cities and providing limited access.

About 1,000 km (600 miles) were completed by 1936, and 6,500 km (4,000 miles) were in use when construction ceased in 1942. The viability of the freeway concept in the was demonstrated by the, The Pennsylvania Turnpike Commission, established in 1937 to raise funds and build a toll road across the, found an unusually favourable situation in the form of an abandoned right-of-way, with many tunnels and excellent grades over much of the route that allowed the tollway to be completed in 1940 to freeway standards.

The turnpike provided two 24-foot carriageways and a 10-foot median with no cross traffic at grade and with complete control of access and at 11 traffic interchanges. Its alignment and grades were designed for high volumes of high-speed traffic and its pavement to accommodate the heaviest trucks.

The favourable public reaction to this new type of highway provided the impetus for the post-World War II toll-road boom in the United States, advanced the start of a major interstate highway program, and influenced highway developments elsewhere. The Pennsylvania Turnpike, originally running from Harrisburg to Pittsburgh, was later extended 100 miles east to Philadelphia and 67 miles west to the Ohio border, making it 327 miles long.

An original feature of the turnpike, later widely copied, was the of restaurant and fueling facilities. The Romans had realized that a coordinated system of roadways connecting the major areas of their empire would be of prime significance for both commercial and military purposes.

1. In the modern era, the nations of Europe first introduced the concept of highway systems.
2. In, for example, the State Department of Roads and Bridges was organized in 1716, and by the middle of the 18th century the country was covered by an extensive network of roads built and maintained primarily by the national government.

In 1797 the road system was divided into three classes of importance: (1) roads leading from Paris to the frontiers, (2) roads leading from frontier to frontier but not passing through Paris, and (3) roads connecting towns. By the early 1920s this general plan remained essentially the same except that a gradual change in class and responsibility had taken place.

At that time the road system was divided into four classes: (1) national highways, improved and maintained by the national government, (2) regional highways, improved and maintained by the department under a road service bureau appointed by the Department Commission, (3) main local roads, connecting smaller cities and villages, built and maintained from funds of the communes supplemented by grants from the department, and (4) township roads, built and maintained by the alone.

While the British recognized the necessity for national support of highways and a national system as early as 1878, it was the Ministry of Transport Act of 1919 that first classified the roadway system into 23,230 miles of Class I roads and 14,737 miles of Class II roads.

Fifty percent of the cost of Class I roads and 25 percent of the cost of Class II roads were to be borne by the national government. In the mid-1930s the need for a national through-traffic system was recognized, and the Trunk Roads Act of 1939, followed by the Trunk Roads Act of 1944, created a system of roadways for through traffic.

The of 1949 authorized existing or new roads to be classified as “motorways” that could be reserved for special classes of traffic. The Highways Act of 1959 swept away all previous highway legislation in England and Wales and replaced it with a set of new laws.

The mammoth U.S. (formally, the National System of Interstate and Defense Highways) developed in response to strong public pressures in the 1950s for a better road system. These pressures culminated in the establishment by President of the Clay Committee in 1954. Following this committee’s recommendations, the and the Highway Revenue Act of 1956 provided funding for an accelerated program of construction.

A federal gasoline tax was established, the funds from which, with other highway-user payments, were placed in a Highway Trust Fund. The federal-state ratio for funding construction of the Interstate System was changed to 90 percent federal and 10 percent state.

It was expected that the system would be completed no later than 1971, but cost increases and planning extended this time by some 25 years. The system grew to a total length of more than 45,000 miles, connecting nearly all the major cities in the United States and carrying more than 20 percent of the nation’s traffic on slightly more than 1 percent of the total road and street system.

The Canadian Highway Act of 1919 provided for a system of 40,000 km (25,000 miles) of highways and provided for a federal allotment for construction not to exceed 40 percent of the cost. By the end of the century, more than 134,000 km (83,000 miles) of highways had been built, of which approximately 16,000 km (9,900 miles) were freeway.

What is concrete road used for?

Concrete Road Advantages – The biggest benefit of concrete road construction is the longevity. Lasting 20-40 years on average, paving in concrete can boast two to four times the lifespan of asphalt. Concrete, it may surprise you to know, is recyclable.

1. Once crushed into gravel, concrete can be used in a variety of ways.
2. High truck volume is better suited to concrete roads, as they hold up better under the weight and pressure.
3. This sturdy surface is less prone to dips and rutting, meaning it is a favorite for freeway construction.
4. Though not immune to the freeze-thaw cycle, concrete is more resistant.

Where asphalt tends to embrittle over time, concrete is more hearty. Concrete tends to be a greener material. Producing it creates less environmental pollution, and cars run with better fuel efficiency on concrete. Concrete is also produced from limestone, which is widely available.

Why do we use concrete roads?

Concrete Roads : GCCA Concrete roads offer durable road construction, help lower vehicle emissions, and reflect more solar radiation than alternatives, such as asphalt. They could also enable in-transport charging of electric vehicles. Roads are a key enabler of development in both cities and rural areas.

Their construction poses the challenge of delivering best performance (in terms of enabling safety, traffic intensity and durability, as well as possible additional duties, such as drainage) as efficiently as possible in terms of resource consumption, cost of construction, and vehicle interaction. Concrete roads offer solutions to these challenges.

Typical construction methods include roller compacted concrete, jointed plain concrete pavement, or continuously reinforced concrete pavement. The visible surface (wearing course) is usually concrete, but a thin asphalt wearing surface can also be added.

• When an asphalt surface is applied, it is usually to address concerns about vehicle noise, even though concrete roads can be specified and constructed to meet acoustic criteria.
• Hybrid solutions are also available with a concrete sublayer and asphalt top layer acting together to form the road structure.

Cementitious solutions for soil stabilisation beneath the road structure are also used. The use of concrete for soil stabilisation at initial build reduces energy and material consumption, as it avoids the need to remove poor soil and replace with alternative materials.According to MIT and others’ research on pavement vehicle interaction, stiffer and smoother roads reduce vehicle emissions.

A further benefit is that concrete roads have a higher albedo, meaning they reflect a higher proportion of solar radiation than darker materials, such as asphalt, mitigating the consequences of warming from CO2 emissions, reducing the urban heat island effect and reducing demand for street lighting.One final area of potential benefit in the future is the potential to charge electric vehicles while driving, due to the ability of certain concrete mixes to conduct electricity. Further reading and sources: Header photo by Paul Moan on Unsplash

: Concrete Roads : GCCA

How a concrete road is built?

Concrete roadways can be laid either slipform using a machine that spreads, shapes and float-finishes the concrete in one operation, or fixed-form, where concrete is extruded into fixed metal forms that are removed when the concrete is hard enough to hold its shape.