Question

Choose from the following:
Gravity system - steel framing, precast concrete, concrete pan joists, or concrete flat plate
Lateral system - moment frame, brace frame, or shear wall
Foundation system - spread and strip footings, mat slab, piles, or drilled piers

11) You are designing a new 21-story student residence hall tower in Brooklyn, New York. The owner has approved your conceptual design of a tall rectangular box above a large open lobby on the ground floor. The geotechnical report shows that the soil on site has a very low (less than 2 k/ft2) bearing capacity. The geotechnical report does not recommend improving the existing soil as a viable strategy for this project due to site restrictions and time constraints. Instead, the report emphasizes that they encountered bedrock between 20-30 feet below grade. The owner would like to fast-track the schedule to minimize interruption on the campus.

Answer 1

For designing a new 21-story student resisdence hall tower on poor load bearing capacity soil

• We use concrete flat plate as gravity system because flat plate system requires simple formwork and reduced depth of slab help to increase the floor to floor height of the building.
• We use shear wall as lateral system because it is easy for construction and implementation and efficient in terrms of construction cost and effectiveness in minimizing soil failure.
• We use pile foundation as foundation system because it have high load capacity and it is corrosion resistance.