Introduction to soil compaction

Soil compaction is a fundamental process in civil engineering and construction that involves increasing the density of soil by reducing the void spaces between soil particles. This process improves the mechanical properties of the soil, such as its resistance, stability and support capacity, which is essential for foundations, structures and infrastructure works.

Compaction is achieved through the application of external energy, either through mechanical or manual equipment, which displaces soil particles for better accommodation and reduction of air volume. It is an essential procedure to guarantee the durability and safety of construction projects, avoiding settlements and structural failures.

Physical mechanisms of compaction

Soil compaction is based on the physical principle of reducing the pores or voids between soil particles, which increases its apparent density. This process involves the readjustment and reorganization of the solid particles, displacing the air contained in the pores to the outside. The amount and type of energy applied determine the effectiveness of the process.

The degree of compaction depends on factors such as soil granulometry, humidity, applied pressure and compaction time. Humidity is particularly critical, since an adequate content allows water to act as a lubricant between particles, facilitating better accommodation and greater density.

Furthermore, compaction can influence the hydraulic properties of the soil, reducing its permeability and increasing shear resistance, key aspects for the stability of structures and control of leaks in civil works.

Optimal humidity-density relationship

Optimum moisture is the water content in the soil that allows maximum dry density to be achieved during compaction. Below this value, the soil is too dry and the particles do not accommodate efficiently, while above, excess water acts as a separating agent, preventing effective compaction.