Soil Compression Index

09/07/25

“How can we measure the compressibility of fine-grained soils to effective stress?”

When soil is drained of water and air, the particles will close together and consolidate, increasing effective stress. The Soil Compressive Index measures the ratio of the change in void ratio to the change in effective vertical stress. The equation solid compression index = change in void ratio/log_10(final effective vertical stress/initial effective vertical stress), or C_c = delta_e/(log_10(sigma_2’/sigma_1’)), governs the solid compression index.