To Design slab and foundation for an RC residential building using TSD

CHALLENGE 12

Aim:

To Design the slab and foundation of the model. Outline the thought process for designing of the elements (column, beam, slab and foundations)

Introduction:

Slabs are the horizontal members in the structure that carry floor loads in the form of dead load, live load and service load. The slabs transfer the load to the beams below. The design of slabs are done by adopting the required thickness, bar size, number and spacing of bar.

Procedure:

Slab Design:

• Open the previous week challenge and validate the model for any errors/warnings
• Run the first order analysis
• First go to the ground floor and untick the members,grids and dimensions

• Select all slabs and provide T10,200 mm spacing for both top and bottom
• Select all the slabs and Design slabs

• Now select the first slab,right click – Check Panel

• Note that the top bars are failing in moment capacity
• Lets try increasing the bar dia or decreasing the spacing

• Now right click to check the panel

• The panel is safe now. Lets repeat the procedure for other slabs too
• If the panel fails in span to effective depth ratio, then try to increase the depth of the slab so that the l/d ratio is within limits
• If a panel fails in moment capacity check, then find the required diameter from the Ast required and assumed spacing and then design the panel

• Ensure that all slabs pass the design criteria

• Repeat the same procedure for the first floor also

Foundation design:

• Go to Design – Settings
• Under Isolated footings, check Reinforcement layout, Foundation size, General parameters, Piles

• Now go to Foundation – Catalogue
• Click on Add
• Add the details of the pile

• Go to Base level
• Foundations – Pile cap column

• Right click any foundation – Check member. Increase the no of piles accordingly
• Select mat foundation for the four columns

Result:

Thus the pile caps and piles are designed according to the design criteria