1 Bag Of Cement Required How Much Water?

1 Bag Of Cement Required How Much Water
How much water required for 1 bag of cement? – Water required per bag cement depend on type of concrete grade, weather condition and strength of concrete do you want. How much water do I need for a bag of cement?, its depending on many factors, water cement ratio which range between 0.40 to 0.6, generally water comes with amount of cement you are using in the concrete mix, so every lb or kg of cement need about minimum 0.35 lb or kg and maximum 0.60 lb or kg of water.

Calculate how much water do you need for a bag of 50kg cement in following steps:- ● assume there is a 50kg bag of cement and water cement ratio range between 0.4 to 0.6 ● calculate how much water do you need for a bag of 50kg cement, its depend on water cement ratio would be minimum 0.4 to maximum 0.60, so minimum quantity of water such as 50kg × 0.4 = 20kg, and maximum quantity of water such as 50kg× 0.6 = 30kg ● calculate volume of water in litre required for one bag of cement, as density of water is about 1kg/ litre, so 20kg water = 20 litres and 30kg water = 30 litres, thus you will need 20 to 30 litres of water per 50kg bag of cement.

Regarding this, “how much water required for 1 bag of cement?”, one 50kg bag of cement will require 20 to 30 litres of water, while one 25kg bag will require 10 to 15 litres of water, a 20kg bag will require 8 to 12 litres of water, one 40kg bag will require 16 to 24 litres of water or a 94lb bag of Portland cement will require 4.5 to 7 gallons of water.

How much water is required per bag of cement?

Water = 22.5 kg or litres.

How many Litres of water is one bag of cement?

Volume of 1 bag of cement = 50 Kg or 35 liters. Given amount of water is in liters i.e.30 liters.

What is the ratio of water to cement mix?

The water–cement ratio ( w/c ratio, or water-to-cement ratio, sometimes also called the water-cement factor, f ) is the ratio of the mass of water ( w ) to the mass of cement ( c ) used in a concrete mix: The typical values of this ratio f = w ⁄ c are generally comprised in the interval 0.40 and 0.60. The water-cement ratio of the fresh concrete mix is one of the main, if not the most important, factors determining the quality and properties of hardened concrete, as it directly affects the concrete porosity, and a good concrete is always a concrete as compact and as dense as possible.

A good concrete must be therefore prepared with as little water as possible, but with enough water to hydrate the cement minerals and to properly handle it. A lower ratio leads to higher strength and durability, but may make the mix more difficult to work with and form. Workability can be resolved with the use of plasticizers or super-plasticizers,

A higher ratio gives a too fluid concrete mix resulting in a too porous hardened concrete of poor quality. Often, the concept also refers to the ratio of water to cementitious materials, w/cm. Cementitious materials include cement and supplementary cementitious materials such as ground granulated blast-furnace slag (GGBFS), fly ash (FA), silica fume (SF), rice husk ash (RHA), metakaolin (MK), and natural pozzolans,

  1. Most of supplementary cementitious materials (SCM) are byproducts of other industries presenting interesting hydraulic binding properties.
  2. After reaction with alkalis (GGBFS activation) and portlandite ( Ca(OH) 2 ), they also form calcium silicate hydrates (C-S-H), the “gluing phase” present in the hardened cement paste.

These additional C-S-H are filling the concrete porosity and thus contribute to strengthen concrete. SCMs also help reducing the clinker content in concrete and therefore saving energy and minimizing costs, while recycling industrial wastes otherwise aimed to landfill,

  • The effect of the water-to-cement (w/c) ratio onto the mechanical strength of concrete was first studied by René Féret (1892) in France, and then by Duff A.
  • Abrams (1918) (inventor of the concrete slump test ) in the USA, and by Jean Bolomey (1929) in Switzerland.
  • The 1997 Uniform Building Code specifies a maximum of 0.5 w/c ratio when concrete is exposed to freezing and thawing in moist conditions or to de-icing salts, and a maximum of 0.45 w/c ratio for concrete in severe, or very severe, sulfate conditions.

Concrete hardens as a result of the chemical reaction between cement and water (known as hydration and producing heat ). For every mass ( kilogram, pound, or any unit of weight ) of cement (c), about 0.35 mass of water (w) is needed to fully complete the hydration reactions.

  1. However, a fresh concrete with a w/c ratio of 0.35 may not mix thoroughly, and may not flow well enough to be correctly placed and to fill all the voids in the forms, especially in the case of a dense steel reinforcement,
  2. More water is therefore used than is chemically and physically necessary to react with cement.

Water–cement ratios in the range of 0.40 to 0.60 are typically used. For higher-strength concrete, lower w/c ratios are necessary, along with a plasticizer to increase flowability. A w/c ratio higher than 0.60 is not acceptable as fresh concrete becomes “soup” and leads to a higher porosity and to very poor quality hardened concrete as publicly stated by Prof.

Gustave Magnel (1889-1955, Ghent University, Belgium) during an official address to American building contractors at the occasion of one of his visits in the United States in the 1950’s to build the first prestressed concrete girder bridge in the USA: the Walnut Lane Memorial Bridge in Philadelphia open to traffic in 1951.

The famous sentence of Gustave Magnel, facing reluctance from a contractor, when he was requiring a very low w/c ratio, zero-slump, concrete for casting the girders of this bridge remains in many memories: “American makes soup, not concrete”, When the excess water added to improve the workability of fresh concrete, and not consumed by the hydration reactions, leaves concrete as it hardens and dries, it results in an increased concrete porosity only filled by air,

A higher porosity reduces the final strength of concrete because the air present in the pores is compressible and concrete microstructure can be more easily ” crushed “. Moreover, a higher porosity also increases the hydraulic conductivity ( K, m/s) of concrete and the effective diffusion coefficients ( D e, m 2 /s) of solutes and dissolved gases in the concrete matrix.

This increases water ingress into concrete, accelerates its dissolution ( calcium leaching ), favors harmful expansive chemical reactions ( ASR, DEF), and facilitates the transport of aggressive chemical species such as chlorides ( pitting corrosion of reinforced bars ) and sulfates (internal and external sulfate attacks, ISA and ESA, of concrete) inside the concrete porosity.

When cementitious materials are used to encapsulate toxic heavy metals or radionuclides, a lower w/c ratio is required to decrease the matrix porosity and the effective diffusion coefficients of the immobilized elements in the cementitious matrix. A lower w/c ratio also contributes to minimize the leaching of the toxic elements out of the immobilization material.

A higher porosity also facilitates the diffusion of gases into the concrete microstructure, A faster diffusion of atmospheric CO 2 increases the concrete carbonation rate, When the carbonation front reaches the steel reinforcements (rebar), the pH of the concrete pore water at the steel surface decreases.

  • At a pH value lower than 10.5, the carbon steel is no longuer passivated by an alkaline pH and starts to corrode ( general corrosion ).
  • A faster diffusion of oxygen ( O 2 ) into the concrete microstructure also accelerates the rebar corrosion.
  • Moreover, on the long term, a concrete mix with too much water will experience more creep and drying shrinkage as excess water leaves the concrete porosity, resulting in internal cracks and visible fractures (particularly around inside corners), which again will reduce the concrete mechanical strength.
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Finally, water added in excess also facilitates the segregation of fine and coarse aggregates ( sand and gravels ) from the fresh cement paste and causes the formation of honeycombs (pockets of gravels without hardened cement paste) in concrete walls and around rebar.

  1. It also causes water bleeding at the surface of concrete slabs or rafts (with a dusty surface left after water evaporation).
  2. For all the afore mentioned reasons, it is strictly forbidden to add extra water to a ready-mix concrete truck when the delivery time is exceeded, and the concrete becomes difficult to pour because it starts to set.

Such diluted concrete immediately loses any official certification and the responsibility of the contractor accepting such a deleterious practice is also engaged. In the worst case, an addition of superplasticizer can be made to increase again the concrete workability and to salvage the content of a ready-mix concrete truck when the maximum concrete delivery time is not exceeded.

What is the best mix for cement?

Ratios – If you do not get the ratio correct, then it can have negative consequences for your construction. For example, if you add too much water to the mortar mix, then it will not properly glue the bricks together. Then, over time the mortar will crumble and not withstand bad weather conditions.

On the other hand, if you add too much mortar mix, then the mortar might easily crack or shrink. Cracking can cause many problems for you in the long run. The best consistency of mortar for bricklaying is for it to be wet and thin. Only a small amount is used when layering. However, some jobs like fitting a roof may require it to be slightly thicker.

The standard ratio for average mortar mix is 3:1 or 4:1 for bricklaying. If you are using a pointing mix, then you should have a ratio of 1:4 or 1:5 mortar to sand. As for concrete, it depends on the strength you need it to be at. Usually, it is good practice to mix concrete at 1:2 mix to materials.

How much water do I need for 30 kg of concrete?

Add approximately 2.7 L (2.85 qts) of clean water per 30 KG (66 lb) bag or enough to achieve a workable mix. Avoid a soupy mix.

What is free water cement ratio?

More or less water – testing the cement – The natural water-cement mixing ratio is around 44% water by weight of cement. So if you have 1 kg of dry cement, the amount of water to get the best hydration and curing is 440 gr (or 0.44 liter). Free water is a standard lab test done for cement slurries (described in detail in API RP 10B).

  1. It is basically mixing the cement slurry, then let it sit for two hrs before measuring the percentage of free water – basically the visually, almost clear water on top of the slurry.
  2. The test can be carried out either at room temperature vertically and at an angle, or at downhole temperature and conditions.

Normally you will have more free water at higher temperatures. I would suggest that values over 2% are signs of a slurry not well designed. Download free eBook: Guidelines for setting cement plugs,

How do you mix cement?

Mixing a cement mortar or concrete in 5 steps – Step 1: Start measuring your ingredients Using the manufacturer’s recommendations, place the cement, sand, (aggregates if making concrete), and water into separate plastic buckets. For a standard mortar mix this normally on a ratio basis (usually around 3 or 4 parts building sand to 1 part cement) recommendations vary – but you don’t want the mixture to be too wet or too dry.

  • In terms of the ratio for concrete, it depends on what strength you are trying to achieve, but as a general guide a standard concrete mix would be 1 part cement to 2 parts sand to 4 parts aggregates.
  • For foundations, a mix of 1 part cement to 3 parts sand to 6 parts aggregates can be used.
  • Measure around half of the cement, sand and aggregates (for a concrete mix only) you’re going to mix.

Using half now will prevent the mix from drying out before you get chance to use all of it – you can mix the other half later. Tip the sand and aggregates (if making a concrete mix) onto your mixing board or into your container. If using a board, form a crater in the middle of the pile.

Measure out half the cement you’re using and pour this into the middle of the crater, which should create a cone-like shape. Warning, This will kick-up dust when you pour the cement out, so ensure your protective mask or mouth protector is in place. Step 2: Begin mixing It’s time to start mixing. Using your shovel, mix your ingredients together, working the shovel around the pile of cement, sand and aggregates (if making concrete mix).

There is no specific method here, simply turn the pile over around three to four times to evenly mix everything and get a consistent colour throughout your pile. Bring your pile together again in a cone-like shape and create another crater in the middle.

Size-wise, the crater should be around half the diameter of the mound itself. To fill in this crater, you’re going to use your water. Again, there’s no precise amount to add, just pour in enough water to fill the crater slightly – enough to form a smooth paste once you start mixing it. Move the sides of your crater into the mixture and turn it over to evenly distribute the water throughout your mixture.

As the water starts to absorb into your ingredients, you need to repeat this process, whether it’s on a wooden mixing board or in a container. Keep on turning your mix until the mixture is wet. Don’t worry if it’s doesn’t seem perfect, you’ll be testing the consistency next.

Why do we add water to cement?

What is in This Stuff? The importance of concrete in modern society cannot be overestimated. Look around you and you will find concrete structures everywhere such as buildings, roads, bridges, and dams. There is no escaping the impact concrete makes on your everyday life.

  • So what is it? Concrete is a composite material which is made up of a filler and a binder.
  • The binder (cement paste) “glues” the filler together to form a synthetic conglomerate.
  • The constituents used for the binder are cement and water, while the filler can be fine or coarse aggregate.
  • The role of these constituents will be discussed in this section.

Cement, as it is commonly known, is a mixture of compounds made by burning limestone and clay together at very high temperatures ranging from 1400 to 1600 ]C. Although there are other cements for special purposes, this module will focus solely on portland cement and its properties.

The production of portland cement begins with the quarrying of limestone, CaCO 3, Huge crushers break the blasted limestone into small pieces. The crushed limestone is then mixed with clay (or shale), sand, and iron ore and ground together to form a homogeneous powder. However, this powder is microscopically heterogeneous.

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(See flowchart.) Figure 1: A flow diagram of Portland Cement production. The mixture is heated in kilns that are long rotating steel cylinders on an incline. The kilns may be up to 6 meters in diameter and 180 meters in length. The mixture of raw materials enters at the high end of the cylinder and slowly moves along the length of the kiln due to the constant rotation and inclination. Figure 2: Schematic diagram of rotary kiln. As the mixture moves down the cylinder, it progresses through four stages of transformation. Initially, any free water in the powder is lost by evaporation. Next, decomposition occurs from the loss of bound water and carbon dioxide.

  1. This is called calcination,
  2. The third stage is called clinkering.
  3. During this stage, the calcium silicates are formed.
  4. The final stage is the cooling stage.
  5. The marble-sized pieces produced by the kiln are referred to as clinker,
  6. Clinker is actually a mixture of four compounds which will be discussed later.

The clinker is cooled, ground, and mixed with a small amount of gypsum (which regulates setting) to produce the general-purpose portland cement. Water is the key ingredient, which when mixed with cement, forms a paste that binds the aggregate together.

The water causes the hardening of concrete through a process called hydration. Hydration is a chemical reaction in which the major compounds in cement form chemical bonds with water molecules and become hydrates or hydration products. Details of the hydration process are explored in the next section. The water needs to be pure in order to prevent side reactions from occurring which may weaken the concrete or otherwise interfere with the hydration process.

The role of water is important because the water to cement ratio is the most critical factor in the production of “perfect” concrete. Too much water reduces concrete strength, while too little will make the concrete unworkable. Concrete needs to be workable so that it may be consolidated and shaped into different forms (i.e.

walls, domes, etc.). Because concrete must be both strong and workable, a careful balance of the cement to water ratio is required when making concrete. Aggregates are chemically inert, solid bodies held together by the cement. Aggregates come in various shapes, sizes, and materials ranging from fine particles of sand to large, coarse rocks.

Because cement is the most expensive ingredient in making concrete, it is desirable to minimize the amount of cement used.70 to 80% of the volume of concrete is aggregate keeping the cost of the concrete low. The selection of an aggregate is determined, in part, by the desired characteristics of the concrete.

For example, the density of concrete is determined by the density of the aggregate. Soft, porous aggregates can result in weak concrete with low wear resistance, while using hard aggregates can make strong concrete with a high resistance to abrasion. Aggregates should be clean, hard, and strong. The aggregate is usually washed to remove any dust, silt, clay, organic matter, or other impurities that would interfere with the bonding reaction with the cement paste.

It is then separated into various sizes by passing the material through a series of screens with different size openings. Refer to Demonstration 1 Table 1: Classes of Aggregates

class examples of aggregates used uses
ultra-lightweight vermiculite ceramic spheres perlite lightweight concrete which can be sawed or nailed, also for its insulating properties
lightweight expanded clay shale or slate crushed brick used primarily for making lightweight concrete for structures, also used for its insulating properties.
normal weight crushed limestone sand river gravel crushed recycled concrete used for normal concrete projects
heavyweight steel or iron shot steel or iron pellets used for making high density concrete for shielding against nuclear radiation

Refer to Demonstration 2 The choice of aggregate is determined by the proposed use of the concrete. Normally sand, gravel, and crushed stone are used as aggregates to make concrete. The aggregate should be well-graded to improve packing efficiency and minimize the amount of cement paste needed.

  1. Also, this makes the concrete more workable.
  2. Refer to Demonstration 3 Properties of Concrete Concrete has many properties that make it a popular construction material.
  3. The correct proportion of ingredients, placement, and curing are needed in order for these properties to be optimal.
  4. Good-quality concrete has many advantages that add to its popularity.

First, it is economical when ingredients are readily available. Concrete’s long life and relatively low maintenance requirements increase its economic benefits. Concrete is not as likely to rot, corrode, or decay as other building materials. Concrete has the ability to be molded or cast into almost any desired shape.

Building of the molds and casting can occur on the work-site which reduces costs. Concrete is a non-combustible material which makes it fire-safe and able withstand high temperatures. It is resistant to wind, water, rodents, and insects. Hence, concrete is often used for storm shelters. Concrete does have some limitations despite its numerous advantages.

Concrete has a relatively low tensile strength (compared to other building materials), low ductility, low strength-to-weight ratio, and is susceptible to cracking. Concrete remains the material of choice for many applications regardless of these limitations.

  • Hydration of Portland Cement Concrete is prepared by mixing cement, water, and aggregate together to make a workable paste.
  • It is molded or placed as desired, consolidated, and then left to harden.
  • Concrete does not need to dry out in order to harden as commonly thought.
  • The concrete (or specifically, the cement in it) needs moisture to hydrate and cure (harden).

When concrete dries, it actually stops getting stronger. Concrete with too little water may be dry but is not fully reacted. The properties of such a concrete would be less than that of a wet concrete. The reaction of water with the cement in concrete is extremely important to its properties and reactions may continue for many years.

Cement Compound Weight Percentage Chemical Formula
Tricalcium silicate 50 % Ca 3 SiO 5 or 3CaO, SiO 2
Dicalcium silicate 25 % Ca 2 SiO 4 or 2CaO, SiO 2
Tricalcium aluminate 10 % Ca 3 Al 2 O 6 or 3CaO, Al 2 O 3
Tetracalcium aluminoferrite 10 % Ca 4 Al 2 Fe 2 O 10 or 4CaO, Al 2 O 3, Fe 2 O 3
Gypsum 5 % CaSO 4,2H 2 O

Table 2: Composition of portland cement with chemical composition and weight percent. When water is added to cement, each of the compounds undergoes hydration and contributes to the final concrete product. Only the calcium silicates contribute to strength. Tricalcium silicate is responsible for most of the early strength (first 7 days). Dicalcium silicate, which reacts more slowly, contributes only to the strength at later times. Tricalcium silicate will be discussed in the greatest detail. The equation for the hydration of tricalcium silicate is given by: Tricalcium silicate + Water->Calcium silicate hydrate+Calcium hydroxide + heat 2 Ca 3 SiO 5 + 7 H 2 O -> 3 CaO,2SiO 2,4H 2 O + 3 Ca(OH) 2 + 173.6kJ Upon the addition of water, tricalcium silicate rapidly reacts to release calcium ions, hydroxide ions, and a large amount of heat. The pH quickly rises to over 12 because of the release of alkaline hydroxide (OH – ) ions. This initial hydrolysis slows down quickly after it starts resulting in a decrease in heat evolved. The reaction slowly continues producing calcium and hydroxide ions until the system becomes saturated. Once this occurs, the calcium hydroxide starts to crystallize. Simultaneously, calcium silicate hydrate begins to form. Ions precipitate out of solution accelerating the reaction of tricalcium silicate to calcium and hydroxide ions. (Le Chatlier’s principle). The evolution of heat is then dramatically increased. The formation of the calcium hydroxide and calcium silicate hydrate crystals provide “seeds” upon which more calcium silicate hydrate can form. The calcium silicate hydrate crystals grow thicker making it more difficult for water molecules to reach the unhydrated tricalcium silicate. The speed of the reaction is now controlled by the rate at which water molecules diffuse through the calcium silicate hydrate coating. This coating thickens over time causing the production of calcium silicate hydrate to become slower and slower. Figure 3: Schematic illustration of the pores in calcium silicate through different stages of hydration. The above diagrams represent the formation of pores as calcium silicate hydrate is formed. Note in diagram (a) that hydration has not yet occurred and the pores (empty spaces between grains) are filled with water. Diagram (b) represents the beginning of hydration. In diagram (c), the hydration continues. Although empty spaces still exist, they are filled with water and calcium hydroxide. Diagram (d) shows nearly hardened cement paste. Note that the majority of space is filled with calcium silicate hydrate. That which is not filled with the hardened hydrate is primarily calcium hydroxide solution. The hydration will continue as long as water is present and there are still unhydrated compounds in the cement paste. Dicalcium silicate also affects the strength of concrete through its hydration. Dicalcium silicate reacts with water in a similar manner compared to tricalcium silicate, but much more slowly. The heat released is less than that by the hydration of tricalcium silicate because the dicalcium silicate is much less reactive. The products from the hydration of dicalcium silicate are the same as those for tricalcium silicate: Dicalcium silicate + Water->Calcium silicate hydrate + Calcium hydroxide +heat 2 Ca 2 SiO 4 + 5 H 2 O-> 3 CaO,2SiO 2,4H 2 O + Ca(OH) 2 + 58.6 kJ The other major components of portland cement, tricalcium aluminate and tetracalcium aluminoferrite also react with water. Their hydration chemistry is more complicated as they involve reactions with the gypsum as well. Because these reactions do not contribute significantly to strength, they will be neglected in this discussion. Although we have treated the hydration of each cement compound independently, this is not completely accurate. The rate of hydration of a compound may be affected by varying the concentration of another. In general, the rates of hydration during the first few days ranked from fastest to slowest are: tricalcium aluminate > tricalcium silicate > tetracalcium aluminoferrite > dicalcium silicate. Refer to Demonstration 4 Heat is evolved with cement hydration. This is due to the breaking and making of chemical bonds during hydration. The heat generated is shown below as a function of time. Figure 4: Rate of heat evolution during the hydration of portland cement The stage I hydrolysis of the cement compounds occurs rapidly with a temperature increase of several degrees. Stage II is known as the dormancy period. The evolution of heat slows dramatically in this stage.

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The dormancy period can last from one to three hours. During this period, the concrete is in a plastic state which allows the concrete to be transported and placed without any major difficulty. This is particularly important for the construction trade who must transport concrete to the job site. It is at the end of this stage that initial setting begins.

In stages III and IV, the concrete starts to harden and the heat evolution increases due primarily to the hydration of tricalcium silicate. Stage V is reached after 36 hours. The slow formation of hydrate products occurs and continues as long as water and unhydrated silicates are present.

  • Refer to Demonstration 5 Strength of Concrete The strength of concrete is very much dependent upon the hydration reaction just discussed.
  • Water plays a critical role, particularly the amount used.
  • The strength of concrete increases when less water is used to make concrete.
  • The hydration reaction itself consumes a specific amount of water.

Concrete is actually mixed with more water than is needed for the hydration reactions. This extra water is added to give concrete sufficient workability. Flowing concrete is desired to achieve proper filling and composition of the forms, The water not consumed in the hydration reaction will remain in the microstructure pore space. Figure 5: Schematic drawings to demonstrate the relationship between the water/cement ratio and porosity. The empty space (porosity) is determined by the water to cement ratio. The relationship between the water to cement ratio and strength is shown in the graph that follows. Figure 6: A plot of concrete strength as a function of the water to cement ratio. Low water to cement ratio leads to high strength but low workability. High water to cement ratio leads to low strength, but good workability. The physical characteristics of aggregates are shape, texture, and size.

  1. These can indirectly affect strength because they affect the workability of the concrete.
  2. If the aggregate makes the concrete unworkable, the contractor is likely to add more water which will weaken the concrete by increasing the water to cement mass ratio.
  3. Time is also an important factor in determining concrete strength.

Concrete hardens as time passes. Why? Remember the hydration reactions get slower and slower as the tricalcium silicate hydrate forms. It takes a great deal of time (even years!) for all of the bonds to form which determine concrete’s strength. It is common to use a 28-day test to determine the relative strength of concrete.

Concrete’s strength may also be affected by the addition of admixtures. Admixtures are substances other than the key ingredients or reinforcements which are added during the mixing process. Some admixtures add fluidity to concrete while requiring less water to be used. An example of an admixture which affects strength is superplasticizer.

This makes concrete more workable or fluid without adding excess water. A list of some other admixtures and their functions is given below. Note that not all admixtures increase concrete strength. The selection and use of an admixture are based on the need of the concrete user.

TYPE FUNCTION
AIR ENTRAINING improves durability, workability, reduces bleeding, reduces freezing/thawing problems (e.g. special detergents)
SUPERPLASTICIZERS increase strength by decreasing water needed for workable concrete (e.g. special polymers)
RETARDING delays setting time, more long term strength, offsets adverse high temp. weather (e.g. sugar )
ACCELERATING speeds setting time, more early strength, offsets adverse low temp. weather (e.g. calcium chloride)
MINERAL ADMIXTURES improves workability, plasticity, strength (e.g. fly ash)
PIGMENT adds color (e.g. metal oxides)

Table 3: A table of admixtures and their functions. Durability is a very important concern in using concrete for a given application. Concrete provides good performance through the service life of the structure when concrete is mixed properly and care is taken in curing it.

Good concrete can have an infinite life span under the right conditions. Water, although important for concrete hydration and hardening, can also play a role in decreased durability once the structure is built. This is because water can transport harmful chemicals to the interior of the concrete leading to various forms of deterioration.

Such deterioration ultimately adds costs due to maintenance and repair of the concrete structure. The contractor should be able to account for environmental factors and produce a durable concrete structure if these factors are considered when building concrete structures.

How much water is needed for a 50 bag of concrete?

Pour water into the dry mix until the powder is saturated with water. Depending on soil conditions, this will require about 1 gallon (3.8 L) of water per 50 lb (22.7 kg) bag.

How much water is needed for a 20kg bag of concrete?

As a guide, use around 2 litres of water per 20kg bag. Do not over water unless you need to achieve a sloppy mix. The less water the stronger the concrete.

How much water do I need for a 30 kg bag of concrete?

Add approximately 2.7 L (2.85 qts) of clean water per 30 KG (66 lb) bag or enough to achieve a workable mix. Avoid a soupy mix.