Innovative Approach in Modular Housing Structural Engineering Design Using Precast Technology




Mr. Shabbir Lokhandwala (Managing Director)


SLABS Engineering is a Creative structural Engineering firm by a group of IITian's and broadly into Structural engineering and design of Precast high rise buildings. 

Project Brief: "Meriyeden: Yenepoya University Family Accommodation 
SLABS designed the tallest Building in Mangalore using Precast Technology. We optimized the repeatability of elements so as to extract the best use of precast technology. 

G+8 Storied "Meriyeden" Tower is 33m Tall comprising of Shear Walls and HCS as a structural framing system used to transfer gravity and lateral loads to the founding system. 
Project Scale i.e. built-up Area is 1 lakh sq. ft. 
No Plastering required for this project as we had high-quality factory-finished Panels that were aesthetically beautiful and structural of high integrity and strength. 

Foundation comprised of laterite soil with an N value less than 10. For this, we have done a rigorous subsoil structure integration study to eliminate pile foundation. We have used raft foundation for this project leading to an enormous amount of cost-saving.
 
Structural Framing 
Cross Walls / Shear Walls and HCS were used as primary structural framing systems for typical floors built using precast technology. 


Figure 1 Laterite Soil 

We have Transfer Girder Situation at First Floor level as open spaces for parking were required at Ground Floor Level. Construction till 1st Floor Level is cast in Situ and above floors is constructed using precast technology. 

Precast Element Summary 
Following is a brief of a variety of Structural precast elements used in the project. 

Table 1Element Summary of the Project 
Element                          No. of Pieces
Walls                                      1675
Parapet                                  119
Landing + Midlands    24
Stair Flight                            32
Hollow Core Slabs         1341
Bathroom Pods                  208
Beams                                   88
Sunshade i.e. Chajja          204

Graphic Concrete Panels are used to achieve exposed concrete aesthetics revealing architects' visualizations. 

Further, as tabulated Lightweight Bathroom PODS were one of a kind to be used in India for a project of this scale and type. 

Structural Engineering Analysis 
ETABS and SAFE were used to realize the seismic behavior of the Structure and its foundation. 
Building 3D models were built to realize extensively tonnage, erection, and for preparation of shop drawings. 

Time Period of Construction 
The entire building was constructed along with the substructure in a time-breaking record of 5 months and handed over to the clients. All activities were carried out parallel such as installation of external windows, Internal Finishes, MEP, etc. to reduce down the time and utilize precast technology to its optimum level. 

Time-Lapse Video on the youtube channel of SLABS Engineering Private Limited could be found to view the construction of the "Meriyeden" 

Crainage, Erection, and Logistics 
8Tons was the restriction to the maximum weight of the panel; which was considered in the design. Accordingly, Tower Crane was selected for the project. Using Single Tower Crane Entire Project was erected. 

The project Site at Mangalore from the factory was about 450kms but due to roadblock at an intermediate level of the project; the distance to be traveled for transporting the panels was about 750kms. To meet this challenge few of the pallets were brought to the site for the casting of panels to increase Erection Speed. 

MEP Integration 
Electrical Conduits and Junction boxes were added to Wall Panels during Production. 

Routing of Conduit in Plan was done from structural screed before pouring the concrete above the HCS. 

Plumbing Grooves for Kitchen Sink Area were provided in the Wall Panels during Production. 
As Bathroom PODS were used; the outlet of electrical supply and plumbing from POD was coordinated with Main Building surrounding wall panels to provide connectivity to the POD.
 

Figure 2 Conduits congestion at DB Box Junction

 
Figure 4 Routing of Conduits in Plan within Screed 

Concrete and Steel Consumption 
Total Concrete along with UG Sump and Main Building; used is 5745 cu.m and Steel Consumption for the project is 478 Mt. 


Figure 5 Typical Flat Unit: Erection In Progress 

Project Achievements 
Shortest time frame within which the entire  project of 1 lakh sq. ft was completed and handed over to the client; i.e. within 5 months 
Detailed Structural Engineering design including the issue of Shop Drawings of 500+ No.s within the shortest duration was achieved to support the contractor 


Figure 6 3D Erection View 

Use of Variety of Precast Pieces such as the following: 
Graphic Concrete Panels 
Precast Chajja / Sunshade 
Bathroom PODS 
Solid Walls 
Beams 
HCS 
Stair Flight 
Landing/Midlands 
Solid Slabs 

Soil-Structure interaction was widely used for analysis to avoid Pile foundation which led to huge savings in the project
Innovative Connections were used to reduce the cost and time required for the erection of panels
SLABS is playing a pioneering role and has a vision and mission to take precast technology to innovative scale and heights by its contribution in design and construction using the latest technology. 

SLABS is rated to be the leading Precast Technology consultant in India.

For Further Details: 
SLABS Engineering Private Limited 
World Trade Center, Level 9, Tower 2, Opp. EON Free Zone, Kharadi, Pune - 411 014 India. 
T: +91 20 67673489 
E: contact@slabsc.com • www.slabsc.com

 

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