---
title: "Classification of pile foundations"
subject: "Foundation Engineering"
chapter: 8
key: "semester_5/foundation_engineering:pile-classification-material-load"
source: https://www.bctengineer.com/q/semester_5/foundation_engineering/pile-classification-material-load
site: BCT Engineering
---

# Classification of pile foundations

Foundation Engineering · Chapter 8: Pile Foundations

- Asked in: 2080 Bhadra, 4 marks
- Video: [Types of Pile Foundation](https://www.youtube.com/watch?v=eiESCVpyX4I) — Civil Engineering
- Answer checked by Claude Sonnet 5.5 on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/foundation_engineering/pile-classification-material-load
- Whole chapter: https://www.bctengineer.com/md/semester_5/foundation_engineering/chapter-8

## Question

Classify the pile foundations according to their material, load transfer, method of forming and method of installation.

## Short answer

Pile foundations are classified by material (timber, concrete, steel, composite), load transfer (end‑bearing, friction, combined), method of forming (precast or cast‑in‑situ), and method of installation (driven, bored, jacked, screwed).

## Answer

Pile foundations are classified in several ways.

#### 1. According to material
| Type | Notes |
|---|---|
| Timber | Light loads, temporary; length up to 15 to 20 m |
| Concrete (RCC, prestressed) | Precast or cast-in-situ; durable and high capacity |
| Steel (H, pipe, sheet) | High capacity, easy handling and splicing; corrosion |
| Composite | Timber plus concrete, steel plus concrete |

#### 2. According to load transfer
- **End-bearing piles:** tip rests on a hard stratum or rock; shaft passes through weak soil. Load is carried by the point.
- **Friction piles:** the load is transferred by skin friction along the shaft, in thick soft soil where no hard layer is reachable.
- **Combined piles:** both end bearing and friction.

#### 3. According to method of forming
- **Precast piles:** cast and cured in a yard, then driven.
- **Cast-in-situ piles:** concreted in a hole in the ground, with or without casing (bored, driven cast-in-situ).

#### 4. According to method of installation
- **Driven:** by hammer (drop, diesel, hydraulic) or vibratory driver.
- **Bored:** soil removed by auger or rotary rig and concrete placed.
- **Jacked** (pressed) and **screwed** piles for low-vibration sites.

Other classes: by displacement (large, small, non-displacement), by use (bearing, tension, compaction, batter, anchor) and by size (small-diameter micropiles).

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Which is not a material class?
   A. Timber
   B. Concrete
   C. Steel
   D. Friction
   Answer: D. Friction is a load-transfer class. (Key point: Material)

2. Friction piles are used when:
   A. Thick soft soil with no hard layer reachable
   B. Rock is at the surface
   C. Loads are lateral only
   D. Soil is dense gravel
   Answer: A. Load is carried by shaft friction. (Key point: Friction piles)

3. Method of forming classes are:
   A. Precast and cast-in-situ
   B. Timber and steel
   C. Large and small displacement
   D. Bearing and tension
   Answer: A. Piles are either cast in a yard or concreted in the ground. (Key point: Forming)

4. Low-vibration sites suit:
   A. Drop hammer piles
   B. Jacked and screw piles
   C. Diesel hammer piles
   D. Vibratory driven piles
   Answer: B. Pressing or screwing avoids vibration. (Key point: Installation)

## Related in Foundation Engineering

- [Define and classify pile foundations](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Apile-classification-define) — Foundation Engineering, chapter 8
- [Classify shallow and deep foundations](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Aclassify-foundations-soil) — Foundation Engineering, chapter 1, asked 4×
- [Pile capacity in sand, group effect, load test](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Apile-capacity-sand-group-load-test) — Foundation Engineering, chapter 8
- [Allowable load of 4×4 pile group, layered sand](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Apile-group-4x4-figure-dcr) — Foundation Engineering, chapter 8
- [Allowable load of 400 mm pile, layered soil](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Apile-400mm-layered-soil-chart) — Foundation Engineering, chapter 8

## Related in other subjects

- [Classification and installation of power cables](https://www.bctengineer.com/question.md?key=semester_4%2Fpower_system_analysis_i%3Acable-classification-installation) — Power System Analysis I, chapter 2
- [Classification of bridges by structure, material, loading](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Abridge-classification-structure-material-loading) — Transportation Engineering II, chapter 5
- [When pile and mat foundations are chosen](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apile-mat-scenarios) — Building Technology, chapter 2
- [ABC classification and material management](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Aabc-importance-material-mgmt) — Construction Management, chapter 3, asked 2×