Experiment 4: Study of Settlement in Structures
1. Aim
To observe settlement in different structures, identify possible causes, analyze its effects, and propose suitable treatment and preventive strategies.
2. Objectives
- To identify types of settlement in structural elements (uniform, differential, or localized).
- To observe the extent and impact of settlement on serviceability and structural integrity.
- To analyze the possible reasons behind observed settlements.
- To suggest remedial and preventive measures.
- To relate findings with relevant IS codes and explore case studies from literature for deeper understanding.
3. Theoretical Background
Settlement refers to the downward movement of a structure or its components due to compression of the foundation soil.
- Common causes: differential soil compression, inadequate foundation design, changes in groundwater, poor soil compaction, or heavy loads.
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Types of settlement:
- Uniform settlement – affects the whole structure evenly.
- Differential settlement – uneven movement causing structural distress (cracks, tilting).
- Localized settlement – affects a small portion of the structure.
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IS Codes:
- IS 1904: 1986 (Code of Practice for Structural Safety of Buildings: Foundation)
- IS 6403, IS 3370 for related guidelines on soil and foundation behavior.
- Students are encouraged to review relevant case studies of settlement in literature to understand real-world consequences and treatment strategies.
4. Procedure (Sample – for reference only)
- Select buildings or structural elements exhibiting visible signs of settlement (tilting, cracks, uneven flooring).
- Observe and record: location, type of settlement, extent of visible distortion, affected elements.
- Capture clear, properly labelled, numbered, and captioned photographs.
- Analyze the possible causes of settlement based on soil, loading, and construction practices.
- Suggest remedial and preventive measures for the affected structure.
- Compare observations with IS code recommendations and documented case studies.
5. Observations & Data Recording (Sample Table – for reference only)
| Sr. No. |
Structure / Element |
Type of Settlement |
Extent / Severity |
Possible Cause |
Effect on Structure |
Suggested Remedy |
| 1 |
External wall |
Differential |
Moderate |
Uneven soil compression |
Cracks at junctions |
Underpinning, soil stabilization |
| 2 |
RCC column |
Localized |
Severe |
Weak foundation soil |
Tilting, cracking |
Jacketing, micro-piling |
| 3 |
Slab / flooring |
Uniform |
Mild |
Creep and consolidation |
Slight unevenness |
Re-leveling, monitoring |
| 4 |
Retaining wall |
Differential |
Moderate |
Soil erosion, poor drainage |
Wall tilting |
Improve drainage, partial reconstruction |
Students must fill a minimum of 5–6 entries with properly captured, numbered, labelled, and captioned photographs attached in their report.
6. Analysis (Sample – for reference only)
- Compare observed settlements with tolerable limits specified in IS codes.
- Identify whether settlement is uniform, differential, or localized.
- Determine causes of settlement based on soil, load, and construction quality.
- Discuss impact on structural serviceability and safety.
- Support analysis with insights from at least one relevant case study in literature.
7. Treatment Strategies (Sample – for reference only)
- Underpinning or strengthening of foundations.
- Soil stabilization or compaction.
- Drainage improvement to prevent water accumulation.
- Load redistribution or removal of excess load.
- Monitoring and periodic assessment to prevent future settlement.
8. Preventive Measures (Sample – for reference only)
- Conduct thorough geotechnical investigations before construction.
- Design foundations according to IS code recommendations.
- Ensure proper soil compaction and moisture control.
- Avoid overloading beyond design capacity.
- Regular inspection and maintenance to detect early settlement signs.
9. Results (Sample – for reference only)
- Identified locations and types of settlement.
- Possible causes and severity.
- Effects on structural safety and serviceability.
- Suggested remedial and preventive strategies.
- Reference to IS codes and case studies for validation.
10. References / Suggested Reading
- IS 456:2000 – Code of Practice for Plain and Reinforced Concrete
- IS 1904 – Code of Practice for Foundation Design
- “Foundation Engineering Handbook” – Hsai-Yang Fang
- Case studies on settlement of buildings
Note: Students can include additional references from IS codes, papers, or books relevant to settlement issues.
10. Viva Questions (Sample: for reference only - Do not write in the final report)
- What are the different types of settlement in buildings?
- What are the common causes of differential settlement?
- Which IS codes provide guidelines on foundation settlement?
- How does settlement affect serviceability and structural safety?
- Can you cite a real-world case study where settlement caused structural failure?
- What preventive measures can be adopted during design and construction to minimize settlement risks?