Which footing type is similar to a combined footing but supports several columns or walls on a single mat?

Which footing type is similar to a combined footing but supports several columns or walls on a single mat?

• A. Raft Footing
• B. Spread Footing
• C. Pad Footing
• D. Pile Cap

Answer: (A)

The idea being tested is using a single, large base to support multiple columns or walls. A raft footing, also called a mat foundation, is a large reinforced concrete slab that sits under a group of columns or even an entire building footprint, distributing the loads across a wide area. This makes it ideal when several columns are close together and the soil can’t safely support each column with its own footing, or when you want to minimize differential settlement by spreading the load more evenly. This matches the prompt because it describes a footing that supports several columns on one continuous mat, which is exactly what a raft (mat) footing does. It’s different from a spread footing (one column or a row of columns with individual footings) and a pad footing (single column), and it’s also not a pile cap (which sits on piles).

The idea being tested is using a single, large base to support multiple columns or walls. A raft footing, also called a mat foundation, is a large reinforced concrete slab that sits under a group of columns or even an entire building footprint, distributing the loads across a wide area. This makes it ideal when several columns are close together and the soil can’t safely support each column with its own footing, or when you want to minimize differential settlement by spreading the load more evenly.

This matches the prompt because it describes a footing that supports several columns on one continuous mat, which is exactly what a raft (mat) footing does. It’s different from a spread footing (one column or a row of columns with individual footings) and a pad footing (single column), and it’s also not a pile cap (which sits on piles).