Assignment Task
You will design footings using two different approaches as part of this assignment, i.e., (1) using the concept of bearing capacity and (2) using the principles related to soil reactivity. Two of the questions are design-related calculations. Others are more conceptual and test your depth of understanding of the course content.
Questions
1. An open-plan office space is to be built in Adelaide, a semi-arid region of Australia. The footing area of the office space is 16.0 m×22.0 m. Design the footing based on soil reactivity (additional information is presented below). The footing type should be a Waffle Raft where possible. If a waffle raft design is not possible you need to mention, why and what alternative option you are choosing clearly.
Your report should present calculations related to Ys, related site classification, beam layout, and crosssectional details (slab reinforcement, slab thickness, beam depth & other reinforcement details). Use AS2870 – Section 3 for your design which can be downloaded from the course website.
2. a) What are the design considerations for beams of a stiffened raft in a reactive soil site?
b) What is a problem site and provide examples? What sections of the AS2870 provide guidelines for the design of problem sites?
3. Discuss the differences between design principles of footings based on soil reactivity and based on bearing capacity.
The ground conditions along with the material properties for a building site are shown below. Design a footing for a column that will carry an axial load of 850 kN, based on the bearing capacity equations. Assume the factor of safety (FOS) as 2.0.
