Laboratory testing and numerical analysis for expansive soil treated by pozzolanic materials

Abstract EN

This paper presents laboratory and numerical analysis on the behavior of expansive soils treated by Silica fume and Slag as a pozzolanic material.

The laboratory tests divided into two series, the first using conventional oedometer andthe other islaboratory physical model.

Swelling potential of test expansive soil was determined the conventional oedometer.

On the other hand, the untreated and treated expansive soils have been tested using the physical model for 45 days under light load condition.

The numerical studiesare based on simulating the tested soil by Plaxis-3D program.

To model the behavior of expansive soil, elastoplastic models have been used.

Hardening Soil Model (HSM) with volumetric strain value is chosen in this study.

The results of laboratory tests indicated that; the soil contains high clay percentage, with active clay.

Expansive soil treated with 5% of both Silica fume and Slag revealed better improvement with moderate swelling potential.

The results of laboratory models found that; the swelling potential reduced by about 60% for soils treated by 5% of both Silica fume and Slag.

Finally, the results of numerical analysis are found to be closed to thelaboratory model.

The swelling potential estimated from the oedometer test is about 4 times that observed from laboratory model.