This document provides a case study on the Pragati Towers project in Mumbai, India, which consisted of 11 high-rise residential buildings constructed using precast concrete systems. Some key points:
- It was the first large-scale prefabricated high-rise residential project in India, with buildings rising up to 70m tall and over 300 apartments in each tower.
- Innovative connection designs were implemented to allow for prefabricated construction while ensuring equivalent seismic performance to cast-in-place designs. This included emulative horizontal and vertical joint connections between precast wall panels.
- Challenges in adopting precast techniques for the first time in India included gaining acceptance for the new technology and
Prefabricationย is the practice of assembling components of aย structureย in aย factoryย or otherย manufacturingย site, andย transportingย them to theย constructionย site where the structure is to be located.
The document discusses tall buildings and provides case studies of several high-rise buildings including Arihant Aura in Mumbai, Burj Khalifa in Dubai, and The Shard in London. It covers definitions of high-rise buildings, the need for tall structures, and key aspects of high-rise design such as structural systems, foundations, elevators, wind engineering, and cladding. The case study of Burj Khalifa specifically highlights its Y-shaped structural core and tapering profile that help manage wind loads and lateral forces.
This document discusses steel portal frames, which are low-rise structures used for industrial and warehouse buildings. They consist of columns connected by horizontal or pitched beams via moment-resisting connections. This allows the frame to act as a single structural unit and reduces bending moments in the beams. Pin joints are introduced to overcome rotational stresses from the beams to the columns. The document then discusses loads on portal frames, proper joint and foundation design, and bracing requirements. It provides specifications for typical steel sections used in portal frames and dimensions. Finally, it summarizes the steel portal frame roof design of the Turbhe Railway Station in India, which features an 84-meter long semi-circular ribbed arch roof.
This document provides information about space frames, cable structures, and folded plate structures. It defines a space frame as a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can span large areas with few interior supports. Folded plates are assemblies of flat plates rigidly connected along their edges to form a structural system without additional beams. Cable structures derive their strength from tension forces in the cables rather than from bending or compression. Common cable structures include suspension bridges, cable-stayed bridges, and cable-supported roofs.
study of famous housing projects by architect Charles Correa.
1. BELAPUR Housing
2. Kanchanjunga Apartments
3. Tarapur housing
Authors- Richa, Parveen n Aarti
The document discusses different types of high-rise buildings. It defines high-rises and provides reasons for their increasing demand, including scarcity of land and desire for aesthetics. It describes various structural loads high-rises must withstand and common construction materials used. It also lists top 10 high-rise buildings worldwide and examples in Pakistan. Finally, it outlines different high-rise structural systems such as braced frames, shear walls, tube structures, and their advantages.
Prefabricationย is the practice of assembling components of aย structureย in aย factoryย or otherย manufacturingย site, andย transportingย them to theย constructionย site where the structure is to be located.
The document discusses tall buildings and provides case studies of several high-rise buildings including Arihant Aura in Mumbai, Burj Khalifa in Dubai, and The Shard in London. It covers definitions of high-rise buildings, the need for tall structures, and key aspects of high-rise design such as structural systems, foundations, elevators, wind engineering, and cladding. The case study of Burj Khalifa specifically highlights its Y-shaped structural core and tapering profile that help manage wind loads and lateral forces.
This document discusses steel portal frames, which are low-rise structures used for industrial and warehouse buildings. They consist of columns connected by horizontal or pitched beams via moment-resisting connections. This allows the frame to act as a single structural unit and reduces bending moments in the beams. Pin joints are introduced to overcome rotational stresses from the beams to the columns. The document then discusses loads on portal frames, proper joint and foundation design, and bracing requirements. It provides specifications for typical steel sections used in portal frames and dimensions. Finally, it summarizes the steel portal frame roof design of the Turbhe Railway Station in India, which features an 84-meter long semi-circular ribbed arch roof.
This document provides information about space frames, cable structures, and folded plate structures. It defines a space frame as a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can span large areas with few interior supports. Folded plates are assemblies of flat plates rigidly connected along their edges to form a structural system without additional beams. Cable structures derive their strength from tension forces in the cables rather than from bending or compression. Common cable structures include suspension bridges, cable-stayed bridges, and cable-supported roofs.
study of famous housing projects by architect Charles Correa.
1. BELAPUR Housing
2. Kanchanjunga Apartments
3. Tarapur housing
Authors- Richa, Parveen n Aarti
The document discusses different types of high-rise buildings. It defines high-rises and provides reasons for their increasing demand, including scarcity of land and desire for aesthetics. It describes various structural loads high-rises must withstand and common construction materials used. It also lists top 10 high-rise buildings worldwide and examples in Pakistan. Finally, it outlines different high-rise structural systems such as braced frames, shear walls, tube structures, and their advantages.
The Kohinoor Square project is a mixed-use skyscraper development under construction in Mumbai, India. It comprises a 203m main building with commercial and hotel space, and a 142m residential building. The complex utilizes sustainable design features like sky gardens, high-performance glazing, and rainwater harvesting. It has a composite structural system and pile raft foundation to support the tall towers. Floor plans show retail, office, and residential spaces of different sizes across multiple floors.
The document discusses prefabricated construction techniques. Some key points:
- Prefabricated structures are built by assembling standardized components manufactured off-site. This allows for faster, more cost-effective construction.
- Common prefabrication systems include large panel systems using concrete walls and floors, frame systems using precast beams and columns, and slab-column systems with precast floors/walls.
- Prefabricated components provide benefits like controlled quality, weather-resistant construction, and minimized on-site work. Examples of prefabricated elements include concrete panels, beams, columns, and steel frames.
- Connection systems are required to join prefabricated elements together. Applications include industrial,
structural glazing and curtain wall
MATERIAL USED
parts of structural glazing and curtain wall
history of glazing
glass description
case study according material
It is the presentation based on precast concrete construction which includes each and every point and scope which may be useful to civil engineering students
The document describes ferrocement roofs. Ferrocement roofs consist of ferrocement panels that are joined monolithically without nuts and bolts. They are connected to ferrocement purlins and portals through welding and cement. Ferrocement roofs transfer less heat than metal roofs and provide more storage space below since they do not require steel trusses. Ferrocement roofs are superior to metal roofs as they are jointless, transfer less heat, prevent humidity transfer, require less maintenance and have a longer lifespan. The document provides examples of ferrocement usage and goals of developing sustainable ferrocement construction.
The document discusses various cost-effective construction techniques that can be used in India to reduce building costs. Some techniques mentioned include using stabilized compressed earth blocks, fly ash bricks, rat-trap bond brickwork, filler slabs for roofs, and replacing concrete lintels with brick arches. Adopting these alternative materials and construction methods can save 15-40% on building costs while still providing durable structures. Proper selection of materials suited to the local area is important for developing cost-effective construction techniques.
Green Building Case Study on TERI,bangalore.Vinay M
ย
This presentation basically encompasses the green practices which are followed or incorporated in the structure to attain the platinum rating systems and posses the sustainable features that way..!!
PREFABRICATED CONSTRUCTION CASE STUDY: THE HEMISPHEREShivangi Saini
ย
The document summarizes details about The Hemisphere housing project in Greater Noida, India. It describes the project as luxury villas equipped with modern amenities located on a 9-hole golf course. The apartments feature 3 units per floor with golf course views from all units. The structures use a precast construction method with prefabricated wall panels, columns, beams, and staircases that are assembled on site. Connection details are provided for walls, beams, slabs, and columns.
Bc open pre fabricated construction systemAnuj Singhal
ย
The document discusses an open prefabricated construction system. Some key points:
- Prefabrication involves assembling building components in a factory and transporting them to the construction site. This speeds up construction time and lowers costs while ensuring quality.
- An open prefabricated system uses precast concrete or steel components like floors, walls, beams and columns assembled on-site. It can be partially or fully prefabricated.
- Examples of full prefabricated open systems include the Nakagin Capsule Tower in Tokyo, with prefabricated steel living capsules bolted to a central concrete core. Prefabrication allowed efficient off-site assembly and construction.
The Eden Project in Cornwall, UK consists of two giant greenhouse domes that house plant life from different climate zones. The largest dome, Dome B, has a diameter of 125 meters. The domes have a unique double-layer steel structure with hexagonal top and triangular bottom chords. They were constructed using a space frame system of pipes connected by cast iron nodes. The domes are encased in air-filled pillows of ethylene tetrafluoroethylene (EFTE) foil for transparency and lightweight cladding. The unique geometry and structural design of the Eden Project domes allow them to house various plant life on a massive scale while minimizing material usage.
Suzlon One Earth, Pune
This significantly unique office is designed by Christopher Charles, Pune based architect and has received LEED Platinum rating in 2010. He and his partner came up with the concept โOffice in the gardenโ. Spread over 10 acres, this magnificent structure is one of the largest green building projects of the country and is also one of the Indiaโs first buildings to be LEED (Leadership in Energy and Environmental Design)ย certified.
Suzlon One Earth, Pune
Suzlon one earth is 100% powered by onsite and offsite renewable sources.
The campus has 18 hybrid wind turbines that fulfil 7% of the total energy consumption, the rest of energy demand is met from offsite wind turbines.
The structure is designed in a way to ensure maximum daylight exposure thereby reducing artificial lighting consumption.
The infrastructure within the campus is designed to enable water percolation and thereby control storm water runoff thus, contributing towards an increased water table level.
Space structures can take the form of two-dimensional grids, cylindrical vaults, or domes. Tension structures like cable-stayed roofs and bicycle-wheel roofs use highly efficient tensile cables to span large distances. Cable structures are characterized by members, nodes, and connections combining tension cables and compression rings or masts to create graceful curved forms.
DISSERTATION- TRADITIONAL CONSTRUCTION MATERIALS OF RAJASTHANDipesh Jain
ย
DISSERTATION
TRADITIONAL MATERIAL IN RAJASTHAN
INFORMATION
ACKNOLEDGEMENT
ABSTRACT
INTRODUCTION
BACKGROUND
NEED FOR STUDY
AIM
OBJECTIVE
SCOPE
LIMITATION
BOOK CASE STUDY
LIVE CASE STUDY
LITERATURE REVIEW
BOOK REVIEW
REFERENCE
CONCLUSION
DESIGN
DATA COLLECTION
ANALYSIS
RESEARCH DESIGN
FIGURES
TABLES
NEED FOR STUDY
Habib Rahman was one of the first generation architects in India to introduce modernism after independence. He brought the Bauhaus style to India and designed several landmark projects like the New Secretariat in Kolkata, UGC Building in Delhi, and Rabindra Bhawan cultural center that combined modern design with traditional Indian elements like jalis, chajjas, and domes. Rahman's works played a key role in establishing modern architecture suited to the Indian context.
ALTERNATE BUILDING MATERIALS & TECHNOLOGICAL ALTERNATIVES IN CONSTRUCTIONRajesh Kolli
ย
Construction and civil engineering activities have experienced a rapid growth due to improvements in procurement of building materials.
However, the current scenario in the developing construction industry has posed many challenges due to some unsustainable aspects of the highly polluting and the exhaustive nature of building materials.
At the same time, it has also created opportunities for innovative and unconventional resources to emerge due to the widening gap in demand and supply of building materials, as well as the need for energy efficient and economical methods of construction.
Omaxe Heights is a residential apartment complex located in Lucknow, India developed by Omaxe Constructions Ltd. It consists of 11 buildings arranged in a circular planning layout, with 3BHK, 4BHK, and penthouse units. Amenities include tennis courts, swimming pools, a gym, and parking. The project occupies a 28,282 square meter site and was approved by the local development authority. It aims to provide modern housing for high- and middle-income residents in a secure setting with amenities like pools and courts. Some issues were reported with seepage, negative spaces from the circular design, and quality of certain materials.
Amanora Future Towers, Hadapsar, Pune - Case StudyAjinkya Randive
ย
The document describes the Future Towers high-end housing development located in Amanora Park Town, Pune. Some key details include:
- The development consists of 9 towers containing 900 units ranging from studios to 4BHK flats.
- Sustainable design principles are followed, including ample natural light and ventilation in each unit.
- A central atrium and numerous courtyards encourage social interaction and a sense of community.
- Robust security, fire safety, and utilities infrastructure ensure resident safety and comfort.
- While luxury amenities are provided, some criticize a lack of luxury in smaller units and excessive landscape lighting causing pollution.
This document summarizes a case study of a 23-storey precast concrete building in Mumbai, India. It discusses the building design, including the wall panel system and connections between panels. Two computational models are compared: an integrated model assuming perfect shear transfer at joints, and a discrete gap model with no shear transfer. The discrete gap model produced more conservative results with higher forces. Overall, the study found that emulative monolithic wall systems with tie reinforcements and shear keys can provide adequate stability for precast buildings in moderate seismic zones. Modeling shear transfer at joints more accurately could allow for less conservative designs.
STRUCTURAL COST COMPARISON OF LOW RISE BUILDING HAVING MOMENT RESISTING FRAME...IAEME Publication
ย
The document compares the structural cost of low-rise buildings with moment resisting frames and moment resisting frames with shear walls in different seismic zones. It presents a case study of a 4-story residential building modeled in STAAD Pro. The results show that in seismic Zone III, shear walls slightly increase costs but not above 10%. In Zone IV, costs are increased by up to 0.79% with shear walls. Shear walls are found to be more cost-effective in Zone V. Ratios of concrete/area, steel/concrete, and formwork/concrete are lower with shear wall designs. The study concludes shear walls make low-rise buildings more economical and resistant to earthquake damage in high seismic zones.
The Kohinoor Square project is a mixed-use skyscraper development under construction in Mumbai, India. It comprises a 203m main building with commercial and hotel space, and a 142m residential building. The complex utilizes sustainable design features like sky gardens, high-performance glazing, and rainwater harvesting. It has a composite structural system and pile raft foundation to support the tall towers. Floor plans show retail, office, and residential spaces of different sizes across multiple floors.
The document discusses prefabricated construction techniques. Some key points:
- Prefabricated structures are built by assembling standardized components manufactured off-site. This allows for faster, more cost-effective construction.
- Common prefabrication systems include large panel systems using concrete walls and floors, frame systems using precast beams and columns, and slab-column systems with precast floors/walls.
- Prefabricated components provide benefits like controlled quality, weather-resistant construction, and minimized on-site work. Examples of prefabricated elements include concrete panels, beams, columns, and steel frames.
- Connection systems are required to join prefabricated elements together. Applications include industrial,
structural glazing and curtain wall
MATERIAL USED
parts of structural glazing and curtain wall
history of glazing
glass description
case study according material
It is the presentation based on precast concrete construction which includes each and every point and scope which may be useful to civil engineering students
The document describes ferrocement roofs. Ferrocement roofs consist of ferrocement panels that are joined monolithically without nuts and bolts. They are connected to ferrocement purlins and portals through welding and cement. Ferrocement roofs transfer less heat than metal roofs and provide more storage space below since they do not require steel trusses. Ferrocement roofs are superior to metal roofs as they are jointless, transfer less heat, prevent humidity transfer, require less maintenance and have a longer lifespan. The document provides examples of ferrocement usage and goals of developing sustainable ferrocement construction.
The document discusses various cost-effective construction techniques that can be used in India to reduce building costs. Some techniques mentioned include using stabilized compressed earth blocks, fly ash bricks, rat-trap bond brickwork, filler slabs for roofs, and replacing concrete lintels with brick arches. Adopting these alternative materials and construction methods can save 15-40% on building costs while still providing durable structures. Proper selection of materials suited to the local area is important for developing cost-effective construction techniques.
Green Building Case Study on TERI,bangalore.Vinay M
ย
This presentation basically encompasses the green practices which are followed or incorporated in the structure to attain the platinum rating systems and posses the sustainable features that way..!!
PREFABRICATED CONSTRUCTION CASE STUDY: THE HEMISPHEREShivangi Saini
ย
The document summarizes details about The Hemisphere housing project in Greater Noida, India. It describes the project as luxury villas equipped with modern amenities located on a 9-hole golf course. The apartments feature 3 units per floor with golf course views from all units. The structures use a precast construction method with prefabricated wall panels, columns, beams, and staircases that are assembled on site. Connection details are provided for walls, beams, slabs, and columns.
Bc open pre fabricated construction systemAnuj Singhal
ย
The document discusses an open prefabricated construction system. Some key points:
- Prefabrication involves assembling building components in a factory and transporting them to the construction site. This speeds up construction time and lowers costs while ensuring quality.
- An open prefabricated system uses precast concrete or steel components like floors, walls, beams and columns assembled on-site. It can be partially or fully prefabricated.
- Examples of full prefabricated open systems include the Nakagin Capsule Tower in Tokyo, with prefabricated steel living capsules bolted to a central concrete core. Prefabrication allowed efficient off-site assembly and construction.
The Eden Project in Cornwall, UK consists of two giant greenhouse domes that house plant life from different climate zones. The largest dome, Dome B, has a diameter of 125 meters. The domes have a unique double-layer steel structure with hexagonal top and triangular bottom chords. They were constructed using a space frame system of pipes connected by cast iron nodes. The domes are encased in air-filled pillows of ethylene tetrafluoroethylene (EFTE) foil for transparency and lightweight cladding. The unique geometry and structural design of the Eden Project domes allow them to house various plant life on a massive scale while minimizing material usage.
Suzlon One Earth, Pune
This significantly unique office is designed by Christopher Charles, Pune based architect and has received LEED Platinum rating in 2010. He and his partner came up with the concept โOffice in the gardenโ. Spread over 10 acres, this magnificent structure is one of the largest green building projects of the country and is also one of the Indiaโs first buildings to be LEED (Leadership in Energy and Environmental Design)ย certified.
Suzlon One Earth, Pune
Suzlon one earth is 100% powered by onsite and offsite renewable sources.
The campus has 18 hybrid wind turbines that fulfil 7% of the total energy consumption, the rest of energy demand is met from offsite wind turbines.
The structure is designed in a way to ensure maximum daylight exposure thereby reducing artificial lighting consumption.
The infrastructure within the campus is designed to enable water percolation and thereby control storm water runoff thus, contributing towards an increased water table level.
Space structures can take the form of two-dimensional grids, cylindrical vaults, or domes. Tension structures like cable-stayed roofs and bicycle-wheel roofs use highly efficient tensile cables to span large distances. Cable structures are characterized by members, nodes, and connections combining tension cables and compression rings or masts to create graceful curved forms.
DISSERTATION- TRADITIONAL CONSTRUCTION MATERIALS OF RAJASTHANDipesh Jain
ย
DISSERTATION
TRADITIONAL MATERIAL IN RAJASTHAN
INFORMATION
ACKNOLEDGEMENT
ABSTRACT
INTRODUCTION
BACKGROUND
NEED FOR STUDY
AIM
OBJECTIVE
SCOPE
LIMITATION
BOOK CASE STUDY
LIVE CASE STUDY
LITERATURE REVIEW
BOOK REVIEW
REFERENCE
CONCLUSION
DESIGN
DATA COLLECTION
ANALYSIS
RESEARCH DESIGN
FIGURES
TABLES
NEED FOR STUDY
Habib Rahman was one of the first generation architects in India to introduce modernism after independence. He brought the Bauhaus style to India and designed several landmark projects like the New Secretariat in Kolkata, UGC Building in Delhi, and Rabindra Bhawan cultural center that combined modern design with traditional Indian elements like jalis, chajjas, and domes. Rahman's works played a key role in establishing modern architecture suited to the Indian context.
ALTERNATE BUILDING MATERIALS & TECHNOLOGICAL ALTERNATIVES IN CONSTRUCTIONRajesh Kolli
ย
Construction and civil engineering activities have experienced a rapid growth due to improvements in procurement of building materials.
However, the current scenario in the developing construction industry has posed many challenges due to some unsustainable aspects of the highly polluting and the exhaustive nature of building materials.
At the same time, it has also created opportunities for innovative and unconventional resources to emerge due to the widening gap in demand and supply of building materials, as well as the need for energy efficient and economical methods of construction.
Omaxe Heights is a residential apartment complex located in Lucknow, India developed by Omaxe Constructions Ltd. It consists of 11 buildings arranged in a circular planning layout, with 3BHK, 4BHK, and penthouse units. Amenities include tennis courts, swimming pools, a gym, and parking. The project occupies a 28,282 square meter site and was approved by the local development authority. It aims to provide modern housing for high- and middle-income residents in a secure setting with amenities like pools and courts. Some issues were reported with seepage, negative spaces from the circular design, and quality of certain materials.
Amanora Future Towers, Hadapsar, Pune - Case StudyAjinkya Randive
ย
The document describes the Future Towers high-end housing development located in Amanora Park Town, Pune. Some key details include:
- The development consists of 9 towers containing 900 units ranging from studios to 4BHK flats.
- Sustainable design principles are followed, including ample natural light and ventilation in each unit.
- A central atrium and numerous courtyards encourage social interaction and a sense of community.
- Robust security, fire safety, and utilities infrastructure ensure resident safety and comfort.
- While luxury amenities are provided, some criticize a lack of luxury in smaller units and excessive landscape lighting causing pollution.
This document summarizes a case study of a 23-storey precast concrete building in Mumbai, India. It discusses the building design, including the wall panel system and connections between panels. Two computational models are compared: an integrated model assuming perfect shear transfer at joints, and a discrete gap model with no shear transfer. The discrete gap model produced more conservative results with higher forces. Overall, the study found that emulative monolithic wall systems with tie reinforcements and shear keys can provide adequate stability for precast buildings in moderate seismic zones. Modeling shear transfer at joints more accurately could allow for less conservative designs.
STRUCTURAL COST COMPARISON OF LOW RISE BUILDING HAVING MOMENT RESISTING FRAME...IAEME Publication
ย
The document compares the structural cost of low-rise buildings with moment resisting frames and moment resisting frames with shear walls in different seismic zones. It presents a case study of a 4-story residential building modeled in STAAD Pro. The results show that in seismic Zone III, shear walls slightly increase costs but not above 10%. In Zone IV, costs are increased by up to 0.79% with shear walls. Shear walls are found to be more cost-effective in Zone V. Ratios of concrete/area, steel/concrete, and formwork/concrete are lower with shear wall designs. The study concludes shear walls make low-rise buildings more economical and resistant to earthquake damage in high seismic zones.
STRUCTURAL COST COMPARISON OF LOW RISE BUILDING HAVING MOMENT RESISTING FRAME...IAEME Publication
ย
In Bhuj earthquake 2001, there were collapses of many low rise buildings. After a
very severe seismic shaking, it may be far cheaper to repair, or even rebuild the
damaged structure, than to build a no damaged structure in the first place. With the
help of shear walls the structure can be made which will not collapse in earthquake. It
is general perception in minds of people that shear walls are economical for high rise
buildings. Therefore it is necessary to find out cost efficiency of low rise buildings
with shear walls.
Pre-Cast Technology: An Initial Step to Sustainable Developmentijsrd.com
ย
This document discusses precast construction techniques. It begins by defining precast construction as the process of casting concrete structural elements in a factory or temporary plant before transporting them to the construction site for assembly. Precast construction provides advantages like reduced costs, faster construction times, and improved quality. The document then examines different types of precast systems like large panel systems, frame systems, and slab-column systems. It details the assembly sequence and equipment used for precast installation. Advantages are highlighted as reduced construction time and costs, while disadvantages include transportation costs and need for skilled labor. The document concludes that precast construction can help meet housing demands in developing countries in a more sustainable way.
IRJET- Effective Location of Shear Wall, its Significance and Displacement An...IRJET Journal
ย
This document discusses the effective location of shear walls in buildings and analyzes their impact on lateral displacement. It summarizes the results of analyzing a typical 11-story building model in different configurations: without shear walls, with shear walls only at the corners, and with shear walls around the entire perimeter. The analysis found that lateral displacement decreased significantly when shear walls were included. Specifically, total displacement was reduced by over 50% when shear walls were placed around the entire perimeter compared to no shear walls. Properly located shear walls can effectively resist earthquake forces and reduce lateral sway, demonstrating the importance of optimizing shear wall placement in high-rise building design.
IRJET-Effect of Shear Wall on Seismic Performance of RC Open Ground Storey Fr...IRJET Journal
ย
1. The study examines the effect of shear walls on the seismic performance of reinforced concrete open ground storey frame buildings.
2. Linear static and nonlinear static analyses are used to compare the performance of open ground storey buildings with and without shear walls. Various multiplication factors are applied to model strengthened configurations.
3. The results show that shear walls improve the capacity of open ground storey buildings to resist seismic forces but strengthening comes at a higher comparative cost.
IRJET- Study on Shear Wall and Bracing in Irregular Structure and Regular Str...IRJET Journal
ย
This document presents a study on providing expansion joints in irregular and regular structures to improve their seismic performance. A 15-storey building model with an irregular L-shaped plan is created in ETABS software. The model is analyzed using response spectrum analysis for seismic zone V. The behavior of the irregular building is compared to regular models with and without expansion joints. The models include bare frames, shear wall frames, and combinations of shear walls and bracing. Responses such as base shear, story drift, displacement, forces and stiffness are compared between the regular and irregular configurations to evaluate the effectiveness of expansion joints.
IRJET- Analysis of Various Effects on Multistory Building (G+27) by Staad Pro...IRJET Journal
ย
This document analyzes the effects of shear walls on a 28-story building modelled in STAAD Pro software. Three models are considered: one without shear walls and two with shear walls in different locations (inward and outward parts of the building). The models are compared based on load transfer and lateral displacement of structural elements. Results show that providing shear walls in suitable locations significantly reduces displacements due to earthquake and wind loads. The document also reviews previous studies on shear wall behavior and modelling approaches. Methodology describes analyzing a 9-story building model with and without shear walls to determine optimal wall locations based on structural displacement and storey drifting.
Structural Analysis of Unbonded Post-Tensioned Shear WallIRJET Journal
ย
1) The document analyzes the structural behavior of unbonded post-tensioned shear walls through modeling and analysis in ETabs.
2) It compares the performance of a building without a shear wall, with a reinforced concrete shear wall, and with a prestressed shear wall in terms of displacement, story drift, and steel requirement.
3) The results show that the prestressed shear wall reduces displacement by over 50%, story drift by nearly 20%, and steel requirement by nearly 40% compared to the building without a shear wall.
This document analyzes the effects of openings in shear walls on the seismic performance of 15-story reinforced concrete buildings. Finite element models of buildings with different shear wall configurations and opening sizes/shapes are created and analyzed using seismic coefficient and response spectrum methods. The results show that external and internal shear walls reduce column moments and axial forces compared to core-only walls. Larger openings decrease shear wall stiffness and increase seismic demands on structural elements. Response spectrum analysis predicts lower forces than the seismic coefficient method. In conclusion, properly incorporating shear walls can improve seismic performance, but openings negatively impact the walls based on their size, shape, and location.
This document summarizes a study on the effect of soft stories in high-rise buildings. A soft story is one where the lateral stiffness is significantly less than the stories above, such as an open ground floor. Five analytical models of a 12-story reinforced concrete building were created with soft stories at different levels to investigate the structural response. The models were analyzed using SAP2000 software. Placement of the soft story, inclusion or removal of interior columns, and addition of shear walls were varied between models. Results such as displacements, drifts, and shears were compared to evaluate the impact of soft story location and design. The goal was to better understand soft story effects on seismic performance of high-rise structures.
IRJET- Seismic Analysis of Confined Masonry Building and RCC BuildingIRJET Journal
ย
This document discusses a study that compares the seismic analysis of confined masonry buildings and reinforced concrete (RCC) frame buildings. Confined masonry buildings use masonry walls confined by reinforced concrete tie columns and beams, which increases the strength and ductility of the structure compared to unreinforced masonry. The study uses software (ETABS) and manual calculations to analyze and compare the seismic performance of these building types based on parameters like base shear, storey drift, and lateral displacement. It provides background on confined masonry construction and outlines the methodology used for the seismic analysis, which includes calculating the base shear according to Indian codes and using different analysis methods like the response spectrum method.
Effect of modeling of infill walls on performance of multi story rc buildingIAEME Publication
ย
This document summarizes a study on the effect of modeling masonry infill walls in multi-story reinforced concrete buildings. Three models of an 8-story building were analyzed: a bare frame, a frame with infill excluding the ground floor to create a soft story, and a frame with full infill. Nonlinear static pushover analysis was performed on the models. The results showed that modeling full infill improved seismic performance by increasing base shear and stiffness, distributing plastic hinges elastically throughout the structure. The bare frame and soft-story structure had plastic hinges form in the life safety to collapse prevention range, indicating poorer performance, while the full infill structure remained elastic. Therefore, modeling infill walls more
IRJET- A Review on R.C.C. Structure with Fully, Partially and without Infille...IRJET Journal
ย
This document discusses a review on the seismic analysis of reinforced concrete frame structures with fully infilled walls, partially infilled walls, and no infilled walls in different seismic zones in India. It analyzes a G+15 story reinforced concrete frame building in seismic zones IV and V on medium soil using STAAD Pro software. The results for maximum nodal displacement, maximum reactions, maximum base shear, and maximum story shear are compared for different models with full infilled walls, partial infilled walls, and no infilled walls. Infill walls contribute to increased lateral stiffness and seismic resistance of buildings. Neglecting their effects can lead to an unsafe design that underestimates structural damage in seismic regions.
Numerical Optimization of Shoring Towers for Slab Formwork SystemsIJTET Journal
ย
The usage of Shoring Tower for slab formwork is getting increased due to not only because of flexibility in the assemble and
construction over Prop-Supported Slab Formwork but also the capacity to withstand maximum construction working loads. The Shoring Tower is
generally used for the construction of heavy structures like Bridges, Culverts, staging of Retaining walls, etc. However a comprehensive scale down
of the shoring tower design goes well with the large span and increased slab thickness of conventional buildings. This research focuses primarily on
Analysis, Modelling, Design and Adaptability of shoring tower for slab formwork through computer models and optimized. The different models are
made from the combination of diameter of tubes with slab thickness and also with plywood thickness in Solid Works. Periodic analysis is done in
ANSYS for different load combinations with the variations of slab thickness and plywood thickness will gives the optimized results for the slab
formwork systems.
IRJET - Economy in Building Construction Systems of Prefabricated StructuresIRJET Journal
ย
This document discusses prefabricated construction systems and their economic benefits. It describes several prefabricated structural systems including load-bearing wall systems, frame buildings, and two-way span systems. Load-bearing wall buildings can have cross walls or longitudinal walls that carry loads. Frame buildings separate load-bearing and curtain wall elements. Two-way span systems provide rigidity in two directions through floor panels supported on all edges. Prefabricated construction can save costs through standardized, factory-produced components and more efficient construction.
IRJET- Post Peak Response of Reinforced Concrete Frames with and without in F...IRJET Journal
ย
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1. PRAGATI TOWERS, MUMBAI
A real time case study with a focus on design implementation for Pragati Towers โ Stilt+23 floors complete
prefabricated high rise residential project, designed & built by Larsen & Toubro construction for the first time in
India for a seismic zone III location is presented in this paper. Innovative connections are implemented and their
feasibility in regards to the India construction industry is explained with reference to other globally available
systems. Two computational models were investigated to find the effect of modelling the vertical joints between
the wall panels are also presented in this paper. Challenges faced while implementing the adopted precast
techniques such as technology acceptance, design of connections, ensuring water tightness suitable to Indian
building requirements are also discussed. Design concepts to prevent progressive collapse are also highlighted. A
standard bench mark setup for precast housing solutions as a fast track technology achieved.
The demand for housing has increased significantly during last decade all over the world. It is felt particularly in
countries where population growth rate is high and the economy is developing fast. For instance, India is
urbanizing at a pace that is higher than the world average. Its cities today are unable to cope with burgeoning
population. In India that has a housing shortfall of nearly 18.7 million homes (Refer Table 1), and project
execution challenges including shortages in skilled manpower & time constraints. Inflationary trends of Indian
2. economy have increased the cost of building materials to the extent that many developers/contractors find it
difficult to offer an affordable housing to the citizens due to low productivity of labours and wastage of materials.
Considering the above scenario, Larsen & Toubro felt it is important to treat housing construction as a
manufacturing industry. Precast can be better and workable technology which supports our aspiration.
Prefabrication with mechanized building systems, with its adaptability and quality consciousness, provides speedy,
cost efficient and sustainable solution.
PROJECT DETAILS
3. Pragati towers project in Mumbai, India consists of eleven residential high-rise, total precast buildings using
precast concrete system. All towers rise about 70 m above ground. Each tower consists of over 300 apartments
with a total construction area of around 2.6 million square feet. The project was developed by Larsen & Toubro
Realty Limited and Omkar Realtors & Developers Private Limited Joint Venture. The project was designed and
constructed by Larsen & Toubro Construction. The project is divided into two phases. Phase 1 consists of six
towers and Phase 2 has five towers. As of today, three towers of Phase 1 are complete and the next three are under
construction. Phase 2 is scheduled to start during the later part of this year.
Each apartment comprising of 269 square feet of carpet area, consists of a living room, a study room, and a
kitchen along with toilet and bath units, planned for a typical EWS family of four.
DESIGN IMPLEMENTATION
Foundation system of the project consists of piles with pile caps connected with tie beams. Ground floors were
constructed by conventional method i.e In-situ construction. Superstructure (i.e 1st to 23rd floor) consists of
precast construction of RC walls & solid floor slabs, columns, and beams Floor slab is considered to act as a rigid
diaphragm to transfer the lateral forces to walls/columns. Precast concrete RC/shear walled structures, also called
large panel systems, are load bearing members and are capable of carrying the vertical and lateral loads. The wall
panels can be connected to each other and to the floor diaphragm to form an emulative monolithic structure.
DESIGN CODES
Mumbai region is categorized as Seismic Zone 3 (Moderate Seismic Zone โ typical Seismic Zones are defined
from Zone 2 (Least Active) to Zone 5 (Highest)). Mumbai is also a coastal city with design wind speed of 44m/s
(~ 98.5 mph) which was considered for this project. Seismic forces governed the design. The Bureau of Indian
Standards (BIS) specifies building codes in India. IS 456 โ 2006 is regarded as the primary building code for
reinforced concrete structures. IS 1893 โ 2002 provides guidelines for earthquake resistant design and IS 13920โ
4. 1993 provides detailing requirements for ductility in concrete structures subjected to seismic forces. IS 11447 โ
1985 provides design guidelines for large panel prefabricated construction. IS 15916-2010 is the most recent
addition that provides guidelines for Design and Erection of Prefabricated Concrete.
DESIGN PHILOSOPHY
As precast technology was adopted for a high-rise residential structure in India, the emulative design philosophy
was selected based on mutual agreement between the Client, Consultant and Contractor. Onsite, wet grouted joints
for horizontal and vertical connections between walls and in-situ concrete joints for slab-to-wall and slab-to-slab
joints, termed as โstitchedโ joints were selected. ETABS software was used to build the structural model for
analysis. Various modeling approaches were considered and compared to come up with the design forces at all
joints in the structure.
EMULATIVE SYSTEM
Emulative detailing is defined as designing connection system in a precast concrete structure so that its structural
performance is equivalent to that of a conventionally designed cast in place, monolithic concrete structure.
Emulative design creates construction that either is monolithic at the critical joint locations or provides
connections that act as if they are monolithic at those locations. In general, emulative connections involve
connecting reinforcing bars across a joint by lap splicing, welding or couplers. Concrete is made continuous by
filling the joint with high quality non-shrink non-metallic high strength grout in horizontal & vertical joints or cast
in place concrete in vertical joints. Precast concrete members may be used only if they can provide same level of
ductility as that of a monolithic reinforced concrete construction during or after earthquake.
MODELING STRATEGIES
The entire superstructure was modeled primarily using shell elements. The walls were of shell elements and the
slabs of membrane elements. A floor was considered as a rigid diaphragm at the respective level, to transfer the
lateral forces to walls. The horizontal joints of the wall panels were idealized to simulate an equivalent monolithic
behavior, in presence of the continuous vertical dowel bars. Therefore, the shell elements representing the panels
were made continuous at the floor levels. A few beams and columns present in the structure were modeled using
frame elements. Appropriate loads and its combinations, as per relevant clauses in IS codes, for most unfavorable
effects were chosen for design. In absence of a model for shear transfer the vertical joints between the panels were
modeled as the following two extreme conditions.
Integrated Model: In this case, perfect shear transfer was assumed through monolithic behavior of two adjacent
panels connected by the grouted loops. The vertical joint strip was modeled as a 100mm wide strip of shell
element. Discrete gap model: In this model, no shear force was assumed to transfer between the wall panels. To
idealize this condition, a 20mm gap was provided at the vertical joint locations. This uncoupled the adjacent walls.
The walls were connected only at the floor levels by the diaphragm constraints. Figure 5(b) shows the gaps at the
5. location of two joints in the discrete gap model. It was observed from the results that, when a vertical joint was
modeled as a gap i.e discrete gap model, the resulting structure was more flexible and the top displacement was
higher in the gap model, the drift in both the models were within the allowable limit of 0.4%.From the results it
was observed that the integrated model behaves as a perfect vertical cantilever while the other model behaves
differently. Also, the bending moments and shear forces were more in the discrete gap model. Similarly the tensile
forces were also higher, which resulted more number of dowel bars. Since this project was the first of its kind in
India, we also checked w.r.to conservative discrete gap model and provided high amount of reinforcement. The
dowel bars were provided with a uniform lap length of 1.3m from foundation till roof through the precast walls.
From the shear and tension force demand, this constant length of dowel bars was sufficient at all locations.
CONNECTIONS
Connections are needed not only to transfer loads but also to provide continuity and overall monolithic behavior of
the entire structure. A complete system of precast units can be integrated to form a structure that behaves
monolithically with sufficient strength, stiffness & durability to resist seismic & other dynamic loadings. To have
a good interaction of wall elements, the elements have to be connected to the foundation, to each other and to the
adjacent floor diaphragms. The connections act as bridging links between the components. The wall panel
connections can be classified into horizontal joints & vertical joints.
HORIZONTAL JOINT
6. The horizontal joint between the wall panels was adopted via projecting dowel bars from lower walls, inserted into
the dowel tubes of upper wall and grouted using non-shrink, non-metallic grout. The projecting length of dowel
bar was kept at anchorage length. The dowels were entered on the thickness of the wall. Continuity is achieved
through non-contact lap splices of dowel bars in grouted steel corrugated ducts. Traditional method i.e non-contact
lap splices, a construction friendly option with good erection tolerances, was adopted as a replacement to the
expensive proprietary products such as splice sleeve system which is a global practice. An alternate method i.e.
connection with mechanical splice can also be proposed.
Horizontal joint design adopted is based on shear friction concept recommended in PCI standards. Shear friction to
be applied where it is appropriate to consider shear transfer across given plane, such as an existing or potential
crack, an interface between dissimilar materials or an interface between two concrete cast at different times. The
basic assumption in shear friction concept is that concrete within direct shear area being considered will crack.
Ductility is achieved by placing reinforcement across this anticipated crack so that tension developed by
reinforcement will provide a force normal to the crack plane. This normal force in combination with friction at the
crack interface provides shear resistance. The normal compressive reaction across the crack will result in shear
transfer by friction along the crack. Reinforcing bars placed across the joints will transfer additional shear force by
dowel action of the bars, while the force induced by pullout resistance will increase the shear transferred by
friction.
7. An alternate method also adopted & connections are checked as there may exist quality issues & uncertainties in
the preparation of interface between two wall panels. Shear friction & shear key effects of concrete are neglected
in this method. Connection designed as dowel anchored in the conduit i.e in the upper & lower wall panels.
Dowels are usually anchored by bonding the concrete. Load transfer between bars is achieved by lap splices.
Reinforcement bars develop yield strength when they are anchored by embedment in corrugated duct filled with
grout. The corrugated duct had sufficient concrete around it for adequate confinement. The horizontal joint is
designed in such a way to resist shear forces, tensile forces and compressive forces.
VERTICAL JOINT
Vertical joints are the structural joints which have to transfer shear forces. Vertical joints are designed based on
shear friction concept as a global practice. Dowel bars are provided in the form of projected rebarโs. Overlapping
hoops & drop in hoops are tied as confinement reinforcement and the section is poured with cast in place concrete
at joint locations. However, an alternate method was adopted for Pragati towers i.e. Vertical joints were provided
with specially formed shear keys to increase shear stiffness and the shear capacity. Direct diagonal compression
transfer between keys, friction and dowel action are mobilized due to shear displacements at the interface between
the prefabricated concrete panel and the insitu joint concrete. The shear key works as mechanical locks preventing
any significant slip along joint. The horizontal component of the inclined compressive force must be balanced by
transverse tensile stresses. For this purpose transverse reinforcement must be provided connected by means of
loops, anchored in the body of panel. Transverse reinforcement was provided in the form of wire loops
(proprietary products) for ease of erection where there is no site formwork required. Vertical joint was designed
based on Indian standards IS: 11447 โ 1985[11] &fundamental principles. The resistance calculated is only static
resistance. As the project falls in seismic zone 3 there is a possibility of vertical joint to resist cyclic actions
induced by earthquake loading. Shear keys behave a significantly stiff component until the shear key effect is
8. destroyed by cracking or local crushing at the heaviest loaded contact surfaces. When the shear key effect is
decreases due to this degradation of the shear keys, the behavior changes to frictional phase associated with
significant shear slip along the cracked section. As there is insufficient literature & testing available regarding
cyclic actions on shear keys, on the conservative front for the project specified two models were generated &
worst of the same results are adopted in the design.
FLOOR TO FLOOR DIAPHRAGM
The stability of precast concrete buildings is provided in two ways. First the horizontal loads due to wind or
earthquake are transmitted to shear walls by the floor acting as a horizontal deep beam. Floor systems play a key
role in the lateral resistance of building structures by providing diaphragm action. Diaphragm action serves to
transfer lateral load at each level to the lateral load resisting elements and unite individual lateral load resisting
elements into single lateral load resisting system. Floor to floor connection was designed against diaphragm action
& ties are provided to achieve structural integrity. Progressive collapse effects are also taken into
account.Refertofigure10forfloorto floor diaphragm connection details adopted for Pragati towers.
PROGRESSIVE COLLAPSE
In prefabricated construction, the possibility of gas or other explosions which can remove primary structural
elements leading to progressive collapse of the structure shall be taken into account. It is therefore necessary to
consider the possibility of progressive collapse in which the failure or displacement of one element of a structure
causes the failure or displacement of another element and results in the partial or total collapse of building. The
building is designed to prevent progressive collapse as per the Codal provisions.
9. For the stability of structure, three dimensional interactions between structural members are necessary to produce a
robust design. The connections are normally designed for shear and compression. But in the case of accidental
loading such as explosion, high tensile stresses along with large deformations will occur. To take up such forces,
the connections should have sufficient strength, continuity and ductility. Strength is to take up the extra forces
acting, continuity to redistribute the loading in case of accidental collapse and ductility to accommodate large
deformations as well as for energy dissipation. To take care of these demands, tie reinforcements in all the three
dimensions are an absolute necessity. The internal ties are to take up the lateral forces from shear wall action.
Peripheral ties ensure the diaphragm action of the slabs. Floor to wall ties take up the horizontal forces from
anchorage of floors to their support and vertical ties ensure the cantilever action of walls.
To avoid progressive collapse, the structure should be sufficiently robust and redundant. Identification and proper
design of the key elements in the structure is necessary to avoid progressive collapse. Recommendations in the
codes were adopted to find the design load and the required amount of tie reinforcements. Here, tie reinforcements
were provided horizontally, both internally and peripherally. The reinforcement at the shear key locations provide
the horizontal tying and that at the joint regions gives the necessary vertical tying effect. The horizontal ties
provide a cantilever action to hold the damaged parts. The vertical ties help to suspend the lower damaged
elements to the intact upper portions. The horizontal and peripheral tie systems provide a catenary action to bridge
the damaged portion. The wall-to-slab ties help to suspend the debris, and prevent the damaged floor from falling
down on to the intact lower portions.
10. WATER TIGHTNESS
The joint design was looked at, taking into consideration the local tropical climate with heavy monsoons. The
grouted joints helped achieve water tightness. Backer rods were placed at the exterior face of exposed to weather
joints to prevent water entry. In addition, waterproofing sealant was applied at these joints as an additional line of
defense. The gable end faces of the buildings were looked at in great detail due to the direct exposure to heavy
rains. As shown in Figure 12, the horizontal joints on these elevations were detailed with an additional overlapping
nib covering the joint across the length to avoid direct exposure of rain water. The nibs also provided a horizontal
band as an architectural feature on the elevation.
CHALLENGES EXPERIENCED
The task of taking up a high-rise residential building using precast technology was a daunting task. There was a
steep learning curve for all involved to understand the technology and global standard practices and apply the
learnings to the project in a workable fashion within the available resource constraints. Several aspects and
standard practices used overseas were modified to fit the Indian construction practices12. Some of the major
aspects discussed in the paper are summarized below along with the respective solutions followed, in contrast with
standard global practices, to adopt this technology. The knowledge and understanding acquired during this process
will be carried forward to the new projects underway.
TECHNOLOGY ACCEPTANCE BY THE CLIENT & CONSULTANT
The client and consultant graciously accepted the technology based on the examples of precast buildings from
around the world. Most examples were selected such that they matched a majority of project parameters on Pragati
Towers with respect to customer needs, architecture, seismic design and site logistics. Without the clientโs
cooperation, patience and willingness to experiment with a new technology, this project could not have been
conceived and materialized.
11. DESIGN PHILOSOPHY
Jointed construction has been a widely accepted design philosophy globally for precast concrete construction. It
offers the added advantage of speed and ease of construction. However, in-situ reinforced concrete system has
been the most accepted system for residential construction over the last few decades in India. Thus, emulative
design approach was followed instead of jointed design approach. Several methodologies were proposed and
mock-up samples and load tests of critical connections were completed to come up with the final feasible options
that would satisfy the design intent.
DESIGN OF CONNECTIONS
Overseas standard emulative connection details such as sleeve connectors and loop connectors were weighed
against the local design constraints such as cost and production/erection feasibility instead of blind adoption of
methods used overseas. The approaches that worked well such as loop connectors were used with minor
modifications. On the other hand, some approaches such as sleeve dowel connecters were avoided for high import
costs and strict tolerances required for erection and production. Notched half slab concept was used which
provided the comfort of jointed construction to a certain extent along with viable detailing to achieve emulative
behavior
EXECUTIVE SUMMARY & CONCLUSIONS:
1. To meet the demands of large volumes of construction in affordable housing sector in shorter duration there
is a need for a fast track technology in mass housing
2. The emulative monolithic wall system seems to be adequate in moderate seismic zones. The provisions of tie
reinforcements, reinforced shear keys and dowel bars provide the required structural integrity for the precast
system. The modelling of vertical joints without considering the shear transfer through the shear keys, reinforced
with shear links, lead to a conservative design.
3. Vertical joints are designed based on shear friction concept as a global practice & dowel bars are provided in
the form of projected rebarโs, overlapping hoops & drop in hoops etc filled with cast in place concrete at joint
locations.
4. For this project vertical joints are provided with specially formed shear keys to increase shear stiffness and the
shear capacity. The shear key works as mechanical locks preventing any significant slip along joint. Transverse
reinforcement provided in the form of wire loops (proprietary products) for ease of erection where there is no site
formwork required.
5. As there is insufficient literature & testing available regarding cyclic actions on shear keys, on the
conservative front for this project specified two models are generated i.e with & without influence of vertical
joints& worst of the same results are adopted in the design.