Husqvarna, one of our main suppliers, have expanded into groundworks and soil compaction. This groups together compactors, reverse-compactors, trench rammers and similar products. As this is a new range of products for Findasaw we have had to ask a lot of questions to better understand the different machines and how to get the best out of them. It seems only sensible that we share these questions and the answers with our customers.

Q: What is soil compaction?

A: Soil compaction is the process of forcing loose soil into a tight, dense mass. It is normally carried out with a mechanical compactor, or a trench rammer in narrow areas.

Q: Why does soil need compaction?

A: Compacted soil has an increased load bearing capacity. It provides a more stable base for foundational material and helps to prevent water and frost damage. Bulging or buckling on roads are often caused by poorly compacted soil.

Q: What is the difference between soil types?

A: The three major distinctions of soil are cohesive, granular and organic. Cohesive soil is a has a heavy clay content that stick closely together. Granular soils are sandy and loose, with poor water retention. Organic soil is what is commonly found in gardens or on farmland and has a higher concentration of plant waste. Organic soil is not suitable for construction, as organic matter decays and weakens over time.

Q: How much water needs to be added when compacting soil?

A: Too little water will cause the soil to crumble, but too much will cause the soil to shift. A good test is to take a handful of the soil, squeeze it and drop it. The ideal moisture level should allow the soil to mold in your hand when it is squeezed, then break into pieces when it is dropped. If it is too dry it will be powdery and break into fragments when dropped. If it is too wet, it will remain in shape and won’t break when dropped.

Q: Which type of compaction equipment is best?

A: On cohesive soils a rammer or trench roller is the best solution. On granular soils a plate compactor is a better tool to use.

Q: What is overcompaction and undercompaction?

A: Overcompaction will occur if too many passes are made in the same direction. It will reduce soil density. To avoid overcompaction, ensure that passes are made forwards and backwards. Undercompaction is the opposite. Too few passes made with leave the soil too soft and fail to achieve the required density.

There is, or course, a lot more to talk about with regards to groundworks and soil compaction. We will be updating our FAQ page with more relevant information as we explore the new Husqvarna groundworks range more fully. If there are any questions which you would like answered you can contact us and we will do our best to provide and answer.