What Are The Materials Used In Taq Construction?

What Are The Materials Used In Taq Construction
Taq is a traditional construction system once common in Shrinagar (Kashmir). Taq designates a timber laced masonry building, while the same word also indicates the distance between piers comprising a bay. This modular distance has become the unit of measurement for houses in Shrinagar.

  1. A taq building can be several floors high, but still withstand earthquake thanks to the combined use of masonry and wood.
  2. The bearing wall masonry has horizontal ladder-like timber lacings embedded at plinth, floors and lintels levels.
  3. Taq walls were traditionally made of a mixture of brick and rubble stone or sun dried bricks laid in thick mud mortar and faced with hard fired brick, with load bearing piers at regular intervals.

One particularity of taq walls is that the infill masonry panels are not bounded to the piers. This would allow the building to better adapt to differential settlements, which are frequent on the soft soil of Srinagar. Usually the roofs of buildings in Srinagar were heavy, being covered with mud (sod).

  • Apart from providing thermal insulation this system would also help to keep the masonry walls together during an earthquake by imparting some amount of pre-compressive strength.
  • At the floor level, the timber floor joists are comprised between two sets of ladder-like timber lacings.
  • Hence the wooden beams tie the floors of the structure together with the walls.

The behavior of Taq buildings during an earthquake is difficult to model, nevertheless it has been studied extensively, especially in recent years. Researcher Randolph Langenbach has gone deep into the study of Taq and Dhajji Dewari buildings and his writings provide us many insights into the mechanisms that govern these construction systems.

  • When it comes to the seismic performance of Taq buildings, although the walls are brittle, the flexible timber lacings at slab and lintel level along with the configuration of interior partitions seem to be the key to their earthquake resistance.
  • The flexibility of the wooden lacings allows the building components slight displacements while dissipating energy, preventing the walls from falling.

Moreover, Taq buildings have to be regarded as composite building systems in which all the parts are interdependent and work together in a kind of organic balance. Although some of the individual elements are brittle, the specific configuration of Taq buildings confers to the system certain ductility.

The friction within the various part of the building system – that are not tightly bound together – allows to dissipate a good amount of the energy induced by an earthquake, preventing the walls form falling apart. Unluckily the cityscape of Srinagar is rapidly changing as Taq along with Dhajji Dewari – a traditional timber framed building system – are being abandoned in favor of more ‘contemporary’ buildings of dubious strength and aesthetic.

Apart from having constituted for centuries the urban landscape of Srinagar, Taq and Dhajji Dewari buildings are an outstanding example of how the use of wood can be optimized for seismic performance. More interest should be devoted to these buildings and their preservation, as well as to the continuation of traditional construction techniques, which are by all evidence the most appropriate to the character and specificity of the city.

What is Taq construction?

Taq (bhatar) Construction: Taq (or bhatar), con- sists of load-bearing masonry walls with horizontal timbers embedded in them. These timbers are tied together like horizontal ladders that are laid into the walls at each floor level and at the window lintel level.

Why is Taq construction used?

The role of Earthquake Resistant Vernacular Architecture in Kashmir Introduction Vernacular architecture is the response from a community or a group of person’s needs in regards to the built environment using locally available resources. It is tailored to the climatic, geographic, sociological and aesthetic needs of specific localities and emulates local traditions.

  • As it usually a community based activity without qualified architects, the approach tends to be more unpedigreed and constantly evolving.
  • Rural buildings in Kashmir are designed by the people living there and thus reflect the local cultural heritage as well as the strength of the community itself.
  • In general, buildings in Kashmir have relied entirely on mud, bricks, stone and wood for a long time.

In recent times, non-local materials have become more available for the communities living in Kashmir, especially more prosperous regions 1, Background Information Indian-administered Kashmir includes Jammu and Kashmir sharing a border with China, in the north and east.

  • Pakistan-administered Kashmir terrorities are Azad Kashmir and Gilgit-Baltisan which are part of the greater Kashmir region.
  • The Kashmir region is on the northern borders of India and Pakistan and the southwestern border of China.
  • Gilgit-Baltisan is the northern most region of Pakistan-administered Pakistan, bordering Azad Kashmir in the south.

The irregular topography accounts for the variation in temperature and is largely regulated by the Himalayas, surrounding mountainous and water occupying regions. Despite this, Kashmir has still got four distinct seasons with the highest temperatures reaching over 30°C and the winter temperatures as low as -4°C during the nights with snowfall.

The climate is known to milder than other surrounding regions to the relatively low altitude 2, The soil found in Kashmir is described as clayey, loamy rich and light with alluvial origin. Alluvial soils are known to be more vulnerable to ground failure when seismic vibrations take place. Softer soils are found in Srinagar and across the Valley of Kashmir and they can contribute to making an earthquake last longer 3,

The economy of the area heavily relies on agriculture with 60% of the area relying on irrigation for major crops such as rice, maize and wheat. There are dense forests that can be divided into two zones (Sub-Himalayan and Himalayan) providing an invaluable source for timber in construction 4,

Earthquake Risk The Himalayas itself have been created by the collision of two tectonic plates, making it one of the world’s most earthquake prone zones. The Kashmir region is a seismically active experiencing several earthquakes in the Valley of Kashmir throughout history. The boundary of the Indian tectonic plate is colliding with the stationary Eurasian plate creating areas of high stress.

Studies show that the Indian tectonic plate moves at 1.8cm a year beneath the Himalayan tectonic plate. Between 1904-2015, there have been 102 earthquakes recorded at this region and there are records dating back to the 15 th Century detailing severe earthquakes 4,

The built environment around Kashmir has changed to help minimise the impact of these earthquakes Initiatives such as the UNESCO (United Nations Educational, Scientific and Cultural Organization) collaboration with India in 2006 after the 2005 Kashmir Earthquake have advocated for the preservation of vernacular buildings but also to discuss alternatives in earthquake-resistant buildings with world-renowned international experts 5,

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Evolution of Vernacular Buildings Most of the buildings in the Kashmiri area are constructed because of the community’s adaptation to living in a disaster-prone area. Many towns and villages in Kashmir are found on soft soils or on former prehistoric lakes, therefore it is essential to have characteristic yet simple residential houses.

For example, in places with soft water-laden soils, the evolution of timber-laced construction is a necessity for structural survival in the long term. These buildings tend to lean and tilt slightly with little rigidity. For a long time, the heating and cooking systems of these houses has remained intact.

Wood-burning stoves were and still are made from easily sourced mud and a copper vessel embedded into the masonry wall to heat up the water. Due to very little additional expenditure, stoves made from galvanized iron sheets have become more popular. Timber-laced masonry construction systems in Kashmir date back to the 12 th century, however it was only in the beginning of the 19 th century that these systems split into two main traditional construction styles: taq and Dhajji dewari.

  1. There has been other earthquake – resistant vernacular constructions found in Kashmir after the 2005 earthquake, such as balconies resting on wooden joists, well-designed trusses and ceilings with joists that rested on the wooden built bands spread across walls.
  2. There are variations of these styles that are found in heavily mountainous areas where soft soils are not a problem.6 Therefore, the major factors that controlled vernacular architecture are access to good soil for brick-making, to water and to timber, as well as earthquake resistance.

Taq (bhatar) buildings Taq buildings are a traditional form of Kashmiri construction and are known for their resistance against earthquakes. The taq system involves load-bearing masonry walls with horizontal timbers embedded in them. The unreinforced masonry is low-strength which is known as masonry laid in lime-sand or mud mortar.

  1. The masonry piers are tied together in a ladder-like format by the timber beams in each floor and window level.
  2. The symmetrical positioning of windows in a characteristic feature of taqs and is where the name originates from.
  3. These timbers resist earthquake collapse by allowing movement of the masonry and the confinement of the brick mud or rubble stone of the wall.

The timbers allow an increase in ductility when absorbing the energy released from an earthquake. The full weight of the masonry can be placed on the timber allowing the structure to be held in place. These buildings have enough flexibility to sway in an event of an earthquake.

However, the materials in taq are not individually ductile and don’t typically exhibit plastic behaviour under stress. Although, since it works as a system, the behaviour that shows this form of flexibility is because of the energy dissipation from the friction between the timbers and the masonry. This friction only occurs when the masonry has been consisted of mortar made from low-strength mud or lime.

basic building materials in construction of building | concrete | cement | steel | brick | sand

The Kashmiri house size measurements is defined by the number of window bays, for example, a 5 taq house is five window bays wide. All materials that allow flexibility are easily sourced in Kashmir yet these naturally occurring materials tend not to be strong enough to provide rigidity to the buildings.

  • These ancient taq buildings originally possessed structural and traditional Kashmiri patterns and designs, and held a cultural significance amongst communities 7,
  • There has been an area of debate amongst engineers in introducing modern elements to taq buildings, however these have proved to be incompatible.

For example, using steel reinforcement inside the walls however the rusting of steel when iron converts to iron oxide results in an expansion and thus, the force of this has a negative impact on corresponding materials by breaking them, e.g. the masonry. Dhajji dewari The Dhajji dewari buildings is a mixture of timber and masonry construction that is also found in non-earthquake zones. ‘Dhajji dewari’ is a Persian term meaning a ‘patchwork quilt wall’. The walls are lighter and thinner and are made of timber framing with infills of brick or sometimes stone masonry.

  • The wall is usually one-half brick thick and then mostly made of timber and masonry.
  • The infil is commonly brick that is made from fired or unfired clay, or rubble stone in more mountainous regions.
  • The vertical and horizontal cage that is formed by the timber frame allows diagonal movement against sheer stress.

Timber studs are used to subdivide the infill which help resist the progressive destruction of the wall and of diagonal shear cracks. The buildings are usually found in flat terrain and are detached. They are found in more rural areas since urban areas of Kashmir (e.g.

Mirpur, Azad Kashmir) use modern materials such as cement and steel in present time. These materials are affordable to areas where there are less agricultural based jobs, and more industrial based employment. Dhajji buildings in urban areas can also be up to four stories high and more extravagant. In general, Dhajji buildings are mostly found in the western Himalayas in both the Pakistan and Indian-administered sectors of Kashmir.

This construction type has been used for over 200 years due to the speed, cost and availability of the resources required to produce these structures. The skill required is not exhaustive for the labour involved and in fact, easier to repair than to make a new house.

Dhajji buildings tend to perform better after earthquakes than the original taq buildings, however it cannot be a choice for everyone in the region due to economic means. Despite the locally sourced timber, the judicious use of it in taq and Dhajji buildings means that over the years it has become more in demand, especially post-earthquake times.

Towards the 21 st century, several people would construct in reinforced concrete however the disadvantages included the poor thermal performance of hollow concrete block construction, this was especially seen in the cold winter seasons. Rich merchants and politicians tend to have very large houses constructed in the Dhajji format and it works as a multi-family housing unit, especially in a region known to have extended families living together.

  • A lot of Dhajji houses are also used for shelter for livestock.
  • Agriculture and farming are an integral part of Kashmiri society, therefore sheltering animals during an earthquake is essential.
  • It is also difficult for communities to move elsewhere in the region since land ownership is the main form of inheritance and records go back to 500 years 8,

This is another reason why buildings are built upwards on one land plot as well the high density of development in these areas. There is a sense of craftsmanship in making these buildings as simple and reproducible for the community as possible. Cator and Cribbage There are several historic mosques in Srinagar that have employed a cator and cribbage style which is another variation of timber-laced masonry. These structures have also proven to be stable in earthquake-prone regions. The timber-laced masonry is much heavier with a greater use of timber and have been around for approximately 1,000 years. Fig.5: Cater and Cribbage technique A comparison of Modern Vernacular Architecture with Traditional Vernacular Architecture After the 2005 Kashmir Earthquake with a high magnitude of 7.6 killed approximately 80,000 people and over 3 million Kashmiris left homeless.

Despite the government introducing more steel and reinforced construction over the last 20 years, it made little difference to the impact that the earthquake had, infact Dhajji and bhatar construction turned out to be more stable. This result from reinforced concrete has been witnessed in other earthquakes e.g.

Ahmedabad in 2001 and Iran in 2003 8, Survival rates of those trapped under these constructions was higher than those trapped under concrete based buildings. There has been a modernization of cities such as Srinagar involving the replacement of masonry and timber based constructions with reinforced concrete, affecting the aesthetic appeal of the traditional buildings.

  • Local traditional design usually involves large windows for the summer seasons, however with concrete houses, central heating during the harsh winters is poor and a large majority of Kashmiris fall into the lower economical class where they can’t afford the fuel to heat up their homes.
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From simple essay plans, through to full dissertations, you can guarantee we have a service perfectly matched to your needs. View our services Due to their flexibility over the years, Taq and Dhajji buildings have showcased that they can survive low to medium Richter Scale earthquakes.

  • Using natural occurring resources such as mud mortar and locally available supplies such as bricks and wood have allowed Kashmiri traditional houses to have a lower level of thermal conductivity than concrete, and thus greater insulation.
  • This is a crucial need for those living in Kashmir because although the summers are short, they can be very warm therefore a house without windows is futile.

The materials used for these structures is also useful in the sense that they were recyclable, and it was easier to re-build or reuse the materials for another purpose after an earthquake. This is much more difficult for a concrete building. There are more problems left for the residents after a concrete house has collapsed, such as the removal of debris and rescuing survivors.

  1. However there has been strain on the timber supplies due to the deforestation rate increasing as the number of earthquakes and population increase.
  2. This has led to a larger number of cement plants in Kashmir.
  3. Although, high-strength cement-based mortar is now a generic material recommended by most engineers for building on earthquake areas, but Kashmir which experiences considerably larger earthquakes, the mortar ceases to make a beneficial difference once the walls of the building begin cracking.

With timber-based masonry, the low strength mortar is used to hold the bricks apart, rather than together allowing the dissipation of the earthquake’s energy to other units of the structure. Therefore, internal damping is an area that differs between both kinds of buildings.

In addition to these construction problems, many people in the region are more likely to have poor construction practice (due to the more complicated procedures and skills) such as poor mixing or inadequate hydration of concrete which increases the likelihood of a collapse. Tourism has also become an economically beneficial industry in the Kashmir regions providing new employment for its communities, therefore the need to keep its natural attractions is crucial.

Prices of timber have increased over the years too and the cost to maintain wood structures has deterred many residents. Overall, the need for modernization and emulating westernization standards of housing has shifted what the communities want, rather than need.

  • Taq and Dhajji dewari have become a symbol of the old times and the prevalence of architecture as a profession has helped create this shift.
  • International architects and engineers have introduced new ideas and concepts to an area that has little similarity to other places in the world, due to its unique geography and climate.

The consequences of the 2005 Kashmir Earthquake have caused a detachment from traditional architecture, despite the uniqueness and the performance of it under previous natural disasters. Using Vernacular approaches in Modern Times: Yasmeen Lari One architect that has adopted a vernacular approach in the Kashmir regions is Yasmeen Lari.

  1. Lari is Pakistan’s first female architect.
  2. She has been known to be an advocate for the preservation of historical and cultural Pakistani sites.
  3. Like others in Kashmir, she has a keen interest in maintaining cultural heritage yet also having a modern perspective.
  4. She has built 45,000 structures since 2010 withstanding earthquakes and even flash floods.

Lari has also created the Heritage Foundation of Pakistan employing architecture students to teach and train the local community to build more sustainable homes. The foundation aims to increase the involvement of women in rebuilding their homes after natural disasters.

Previously, male family members would be part of the community activity of rebuilding and restoration due to cultural reasons. Her technique involves using mud, bamboo, lime and mix lime with mud to create a strong foundation for buildings. The pillars of the houses consist of bamboo roofs, the walls are made from a mixture of mud, lime and other locally sourced material.

The rood is known as the ‘Karavan roof’, whereby the bamboo can last for 25 years when covered with straw matting, and to make it waterproof a layer of tarpaulin and pozzolana is added. The sizes of the houses range from a single room to a larger room suitable for 5 people, kitchen, bathroom and verandah.

After 3 years, it was found that these houses were still standing and in good condition. The reluctance to use cement, steel and burnt bricks for her was since these high-cost materials don’t work as efficiently under a disaster situation. It also provides help to communities that aren’t as economically stable as others in Kashmir (e.g.

Mirpur in Pakistan has a large British Pakistani population allowing greater expenditure on buildings) and are not in favour of modernisation. The idea behind Lari’s concept is the same that has been used in Kashmir for years before modernisation occurred, it basically ensures that buildings are simple enough to be rebuilt by inhabitants when in need.

  • The importance of local involvement has been witnessed in the building of Taq and Dhajji Dewari buildings.
  • Lari’s main objective is to enhance the focus on heritage methodology and learn from the past and advocate zero-cost and zero-carbon solutions 9,
  • Conclusion In current times, the Dhajji dewari system is still being used in and adapted in places such as Srinagar, although the principles are the same, new additions such as mud mixed with straw for brick infill are being explored.

However, the shift to reinforced concrete buildings is noticeable and has left some taq and Dhajji buildings out of fashion. The combination of vernacular techniques and methods with modern materials and technology are slowly being advocated by groups such as UNESCO.

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Taq and Dhajji dewari systems have become a symbol of continuity and tradition. The idea of improving the quality of life by modernization has overshadowed the need for traditional timber-based masonry buildings in an extremely earthquake zone. The evolution of earthquake resistance buildings in Kashmir has been rushed to the most generic and common answer (reinforced cement construction), but the disadvantages of this have been witnessed by communities, especially poorer communities.

Older designs tend to complement the climate and the resources available to a higher degree but reverting completely back to them is not ideal. There is general rediscovery of the advantages of old fashioned methods by the government too and a conscious shift to a pre-modern Kashmir but with also new building science.

Vernacular Architecture By Henry Glassie – pg 12 Living in Harmony with the Four Elements” 12-14 December 2010 ‘Earthquake Resistant Traditional Construction’ is Not an Oxymoron* The Resilience of Timber and Masonry Structures in the Himalayan Region and Beyond, and its Relevance to Heritage Preservation in Bhutan By Randolph Langenbach Auerbach’s Wilderness Medicine By Paul S. Auerbach, Tracy A Cushing, N. Stuart Harris pg 1926 History of Natural Disasters in Kashmir Valley, Jammu and Kashmir with Special Reference to Earthquakes Sidrat Ul Muntaha Anees M. Sultan Bhat Don’t Tear it Down!Text and Photographs by Randolph Langenbach Preserving the Earthquake Resistant Vernacular Architecture of KashmirBOOK EXCERPT:Showing Forword, (2) pages 59-61: Section 3.6.2 “corner vertical rebar in taq construction”and definition of taq and dhajji dewari construction. FROM:Orig inal publication Info:Produced by UNESCO Cultures and Disasters: Understanding Cultural Framings in Disaster Risk edited by Fred Krüger, Greg Bankoff, Terry Cannon, Benedikt Orlowski, E. Lisa F. Schipper pg 65 Traditional Earthquake Resistant System Kashmir Mohd Akeeb Dar Sajad Ahmad Hazards and the Built Environment: Attaining Built-in Resilience International Journal of Civil and Structural Engineering Research ISSN 2348-7607 (Online) Vol.2, Issue 2, pp: (86-92), Month: October 2014 – March 2015, Available at: www.researchpublish.com Building of a disaster By Shahnawaz Khan Srinagar, July 3, 2014: http://www.tabletwoproductions.com/wp-content/uploads/2013/06/Yasmeen-Lari.pdf

What is the Taq and Dhajji dewari system?

Constructed of a mixture of brick and rubble stone set into a thick bed of mud mortar (Taq), or. with a single layer of modern size brick surrounded by heavy timber (Dhajji-Dewari). The Taq. houses were usually faced with a layer of small, very hard, hand made clinker bricks, known as.

What are the temporary structures in construction site?

Temporary Structures for Construction | Richard J. Driscoll, Consulting Engineer Construction projects often require the use of temporary works to provide access or protection to workers or the public, to protect adjacent structures, or to support temporary loads during construction. Temporary works often include structures, such as excavation support systems, underpinning, scaffolds, bracing and shoring, formwork, falsework, work platforms, decking, roof protection and structures used in on-site contractor facilities.

  1. Temporary works are typically designed by or for the contractor that uses them but may be designed for the project owner or some other party to secure permits, equalize contractor bids or manage project risk.
  2. Even when designed by a contractor, the project owner, design team and other stakeholders may have a vested interest in the performance of a temporary structure.

This may necessitate the development of performance specifications, analysis of permanent work for construction staging or review of the contractor’s design. Richard J. Driscoll, Consulting Engineer (RJDCE) can provide concept development, performance specification, analysis, design and review monitoring of a variety of temporary structural systems used in construction, including support of excavation, underpinning, structural shoring and bracing, bridge-like structures and contractor facilities.

RJDCE presents experience evaluating applicable design standards and methods required for a particular application, designing modifications to existing temporary works and analyzing existing structures for construction loads. In addition, RJDCE can review temporary works designs for owners and abutters, develop and oversee monitoring programs, investigate performance failures and evaluate construction damage claims associated with temporary structures.

Temporary structures for below-ground construction in the urban environment is a specialty area of practice for RJDCE. See also:,,,,, : Temporary Structures for Construction | Richard J. Driscoll, Consulting Engineer

What is BFS in building construction?

Brick Flat Soling (BFS) is mostly used in building construction and road construction.The purpose of using it as concrete bed is to make concrete bed smooth and stable. There is a trend among site engineers to approve BFS work without checking. I know it well because I’m directly related to construction.

A Checklist for Brick Flat Soling:- 1.Material quality: You already know that the required building materials for BFS are 1st class brick and fine aggregate (sand).2.Compaction of sub-soil: Bricks are placed on soil or sand bed. Before placing bricks, check that bed is compacted by hand rammer and by sprinkling water.3.Leveling of bed: Check the compacted surface of bed is leveled properly.

Also check the bed surface is at desired level.4.Frog mark (if any): Check the frog mark of bricks are kept upward direction so that it can make bond with future concrete.5.Brick joints: Check the bricks are jointed as English bond pattern.6.Joint filling: Check the joints are filled with sand.

Why is it called Taq?

DNA polymerase I, thermostable
Large (Klenow) fragment of Taq polA, containing the polA and vestigial domains
Identifiers
Organism Thermus aquaticus
Symbol polA
UniProt P19821
show Search for

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Taq polymerase is a thermostable DNA polymerase I named after the thermophilic eubacterial microorganism Thermus aquaticus, from which it was originally isolated by Chien et al. in 1976. Its name is often abbreviated to Taq or Taq pol, It is frequently used in the polymerase chain reaction (PCR), a method for greatly amplifying the quantity of short segments of DNA,T.

What does Taq stand for?

How and where was this enzyme found? – It was in the 1960s when Thomas D. Brook conducted an experiment in which he was sampling bacteria in the lakes and springs of the Yellowstone National Park. Out of his observations, he discovered threads of bacteria thriving in a hot spring at above 80 degrees.

  1. This was the first-ever bacterial species found to withstand such extreme temperature conditions.
  2. He named it Thermus aquaticus ––abbreviated as “Taq”.
  3. Thermus was used for “stable at a high temperature” and aquaticus because it was found in “hot waters.” Later in 1976, Chien et al.
  4. Isolated a protein molecule from this heat-stable bacteria called Taq polymerase, specifically, Taq DNA Polymerase.

This polymerase can withstand extremely high temperatures and presents an advantage to biologists to perform DNA replication under heated conditions. The most common application of Taq polymerase is its utilization in conducting Polymerase Chain Reaction (PCR), which will be discussed next.

What is the source of Taq polymer?

Taq polymerase used in PCR is obtained from thermophilic bacteria, Thermus aquaticus. This bacteria can survive at extremely high temperatures. So, the correct answer is option C.