The type of pile foundation that is installed through soft strata to build a stable foundation for heavy structures, carrying the load by resistance at its base, is called:
Try it first: pick an option, then read the explanation.
Correct answer: B. end bearing piles
Asked in SSC JE 10/10/2023 (Evening)
Detailed Explanation
When the top soil is too soft for footings but a hard layer (rock, dense sand or gravel) exists at a reachable depth, piles are taken down to that layer.
Why “end bearing piles” Is Correct
Such a pile behaves like a column: the load travels down the shaft and is resisted mainly by the bearing resistance at its base on the firm stratum. This is an end-bearing (point-bearing) pile, and it is the usual choice for heavy structures on soft ground over a firm layer.
| Pile type | How it works / where it is used |
|---|---|
| End-bearing (point-bearing) pile | Passes through soft soil and rests on a hard stratum; carries load at its tip like a column |
| Friction (floating) pile | No hard stratum within reach; carries load by skin friction along its length |
| Compaction pile | Driven into loose sand to densify it and raise its bearing capacity; not meant to carry load itself |
| Tension (uplift) pile | Resists uplift, e.g. under towers, basements below the water table |
| Batter pile | Driven at an angle to resist inclined or horizontal loads |
| Sheet pile | Forms a wall to retain soil or water; not for vertical load |
Why the Other Options Are Wrong
- A. tension piles: Tension piles resist uplift, not downward load.
- C. friction piles: Friction piles rely on skin friction along the shaft, used when no firm stratum is within reach.
- D. screw piles: Screw piles are a method of installation (screwed in), used mainly for light structures or anchorage.
Key Point
Firm stratum at reachable depth → end-bearing pile; no firm stratum → friction pile.
Key Concepts for Students
- Load capacity of a pile = end bearing + skin friction.
- Point-bearing piles on rock do not lose capacity in a group.
- Negative skin friction can add load to end-bearing piles in settling fill.
Practice more: this is question 10 in Shallow and Deep Foundation MCQs – Part 1. Try the whole set and check every answer instantly.