Which term describes a member with a small cross-sectional area used to provide adequate support for a column or wall resting on soil too weak to support the structure using a spread footer?

• A. Pile
• B. Plan
• C. Plinth
• D. Pitch

Answer: (A)

When a structure sits on soil that is too weak to carry a spread footing, a deep foundation element is used to reach stronger soil or rock below. A pile is a slender member with a small cross-section that can be driven or drilled down to deeper bearing strata, providing support for a column or wall resting on weak surface soils. The load from the structure is transferred to deeper soil either by end bearing at the pile tip or by skin friction along the shaft, allowing a small-diameter member to carry large loads. Piles are commonly used under foundations to bridge soft layers and connect to a pile cap that distributes the load to the columns or walls. The other terms describe different things: plan is a layout view, plinth is a base block for a wall, and pitch means slope.