Soil compaction
Soil compaction is the removal of pore spaces within soil structures and drainage channels between soil structures. This inhibits root penetration and the movement of air and water in soil. Ref The HS2 London-West Midlands Environmental Statement, Glossary of terms and list of abbreviations, DETR 2013.
Soil compaction can be purposeful (intentional) or consequential (unintentional) such as settlement that might occur due to vehicle movement.
Intentional soil compaction produces an increase in soil density and a decrease in air volume without producing a decrease in water content. It can improve shear strength, stiffness, bearing capacity and stability, reducing settlement and frost heave. This may be necessary in the construction of bases for highways, embankments and so on, or to create a suitable level base for the construction of a building. Existing soil can be compacted, or layers of new soil can be compacted, taking a site to the required level.
For effective compaction to take place, there must be a mixture of particle sizes so that smaller particles can fill the voids between larger particles. Soils with smooth, spherical particles are easier to compact than soils with irregular particles, although their load-bearing capacity can be lower.
Soils are typically categorised as cohesive soils, granular soils or mixed soils. Cohesive soils can be compacted effectively by impact, such as by rammers or sheepsfoot rollers (tamping rollers). Granular soils can be compacted effectively by vibratory plates and smooth-drum vibratory rollers.
The use of vibrating or oscillating rollers is sometimes referred to as dynamic compaction.
Excessive compaction can lead to soils breaking down and separating. This can cause compacted layers to weaken.
See also: Vibro-compaction.
[edit] Related articles on Designing Buildings Wiki
- Bearing capacity.
- Excavation.
- Geophysical survey.
- Geotechnical engineering.
- Ground conditions.
- Ground heave.
- Ground improvement techniques.
- Ground investigation.
- Ground investigation.
- Groundworks.
- Insitu testing of soils.
- Made ground.
- Soil report.
- Trial pit.
- Types of plant.
- Types of soil.
- Vibro-compaction.
Featured articles and news
Quality Planning for Micro and Small to Medium Sized Enterprises
A CIOB Academy Technical Information sheet.
A briefing on fall protection systems for designers
A legal requirement and an ethical must.
CIOB Ireland launches manifesto for 2024 General Election
A vision for a sustainable, high-quality built environment that benefits all members of society.
Local leaders gain new powers to support local high streets
High Street Rental Auctions to be introduced from December.
Infrastructure sector posts second gain for October
With a boost for housebuilder and commercial developer contract awards.
Sustainable construction design teams survey
Shaping the Future of Sustainable Design: Your Voice Matters.
COP29; impacts of construction and updates
Amid criticism, open letters and calls for reform.
The properties of conservation rooflights
Things to consider when choosing the right product.
Adapting to meet changing needs.
London Build: A festival of construction
Co-located with the London Build Fire & Security Expo.
Tasked with locating groups of 10,000 homes with opportunity.
Delivering radical reform in the UK energy market
What are the benefits, barriers and underlying principles.
Information Management Initiative IMI
Building sector-transforming capabilities in emerging technologies.
Recent study of UK households reveals chilling home truths
Poor insulation, EPC knowledge and lack of understanding as to what retrofit might offer.
Embodied Carbon in the Built Environment
Overview, regulations, detail calculations and much more.
Why the construction sector must embrace workplace mental health support
Let’s talk; more importantly now, than ever.
Ensuring the trustworthiness of AI systems
A key growth area, including impacts for construction.