---
title: "Purposes of foundation soil improvement"
subject: "Foundation Engineering"
chapter: 10
key: "semester_5/foundation_engineering:soil-improvement-purposes"
source: https://www.bctengineer.com/q/semester_5/foundation_engineering/soil-improvement-purposes
site: BCT Engineering
---

# Purposes of foundation soil improvement

Foundation Engineering · Chapter 10: Foundation Soil Improvements

- Asked in: 2075 Asoj, 2 marks
- Video: [Principles of Ground Improvement | Shallow Foundations](https://www.youtube.com/watch?v=2e79-3b6MFM) — Structural Guide
- Answer checked by Claude Sonnet 5.5 on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/foundation_engineering/soil-improvement-purposes
- Whole chapter: https://www.bctengineer.com/md/semester_5/foundation_engineering/chapter-10

## Question

What are the purposes of foundation soil improvement?

## Short answer

Purposes include increasing bearing capacity, reducing settlement, lowering permeability, controlling expansive soil movement, mitigating liquefaction, improving slope stability and enabling shallow foundations instead of deep ones.

## Answer

The purposes of foundation soil improvement are:

1. To increase the bearing capacity and shear strength of weak soil.
2. To reduce total and differential settlement of structures.
3. To reduce permeability and control seepage.
4. To control the swelling and shrinkage of expansive soils.
5. To reduce liquefaction potential of loose saturated sands during earthquakes.
6. To improve slope stability and reduce lateral earth pressure.
7. To make the site suitable for shallow foundations, avoiding costly deep foundations.

## Check yourself

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

1. Which purpose relates to settlement?
   A. Increasing settlement
   B. Increasing swelling
   C. Increasing permeability
   D. Reducing total and differential settlement
   Answer: D. Improvement reduces total and differential settlement of structures. (Key point: Settlement control)

2. What is the purpose for expansive soils?
   A. Increase void ratio
   B. Increase swelling
   C. Reduce shear strength
   D. Control swelling and shrinkage
   Answer: D. Stabilization controls swelling and shrinkage. (Key point: Expansive soils)

3. How does improvement help foundation choice?
   A. Removes need for any foundation
   B. Increases lateral earth pressure
   C. Forces use of deep foundations
   D. Makes the site suitable for shallow foundations, avoiding costly deep foundations
   Answer: D. Improved soil can carry shallow foundations economically. (Key point: Economic benefit)

## Related in Foundation Engineering

- [Methods of soil improvement](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Asoil-improvement-methods-list) — Foundation Engineering, chapter 10, asked 6×
- [Soil improvement techniques; explain two](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Asoil-improvement-explain-two) — Foundation Engineering, chapter 10, asked 2×
- [Arching in soil and its requirements](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Aarching-requirements) — Foundation Engineering, chapter 4, asked 8×
- [Raft 14 m × 21 m, depth of foundation](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Araft-14x21-depth-skempton) — Foundation Engineering, chapter 7
- [Soil stabilization by admixture](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Aadmixture-stabilization) — Foundation Engineering, chapter 10, asked 2×
- [Methods of soil stabilization](https://www.bctengineer.com/question.md?key=semester_5%2Ffoundation_engineering%3Asoil-stabilization-methods) — Foundation Engineering, chapter 10, asked 2×

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- [Foundation settlement, effects, black cotton soil](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asettlement-black-cotton-062ba) — Building Technology, chapter 2
- [Soil exploration, safe bearing capacity, improvement](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aexploration-bc-065s) — Building Technology, chapter 2
- [Water tower foundation on weak stratum](https://www.bctengineer.com/question.md?key=semester_4%2Fsoil_mechanics%3Awater-tower-weak-stratum-stress) — Soil Mechanics, chapter 8, asked 2×
- [Ring foundation 3.60 m stress](https://www.bctengineer.com/question.md?key=semester_4%2Fsoil_mechanics%3Aring-foundation-3-6-m-stress) — Soil Mechanics, chapter 8