Improvement of the strength of soils which comprises granular pumice by injection of cement under low pressure

Abstract

In this study, improvement of granular pumice soils strength by injection method in Nevşehir City (Turkey) was investigated. In the first phase of the study, the geotechnical properties of granular pumice soils were investigated. The specific density, dry unit weight and water absorption value increased with the decrease of grain size. Thus, it can be seen that the bearing capacity of pumice varies depending on the grain size. In the second level, changes in strength of unconfined compression of injected pumice samples were analysed. The samples taken from the field were prepared to 35, 65 and 85 % density, relatively. Pressure of 100 kPa and water/cement ratio of 1.0 was applied to this test samples and the samples were allowed to cure for a period of 7 and 28 days. The results of the study showed that injected pumice soil reached its maximum strength value with 35% relative density and reached its minimum value with 85% relative density. At the end of 28 days curing period, injected pumice soils prepared with 85% relative density have an equivalent strength to C8 concrete class and grouted pumice soils prepared with 35% relative density have an equivalent strength to C12 concrete class.