Simplified Approach of Modelling the Compressibility Behaviour of Unsaturated Soil

The paper deals with the experimental studies made on a typical red soil with the objective of developing a simple model which can be used to understand the compressibility behavior of unsaturated soils. Predictions have been made for the test results of samples with different initial conditions using the model. In the investigation, the response of air filled and water filled pore fractions of unsaturated soil are individually considered and the two responses are added together to get the overall response. With this approach it is possible to predict the unsaturated soil behavior for any level of compaction stress or initial mixing water content and magnitude of suction, knowing only the compressibility of the air filled and water filled pore fractions. The test results, analysis and validation of the proposed model for the compressibility behavior are discussed and presented in the paper.