Strength Behaviour of Cement Stabilised Dredged Soil

Abstract

Dredged soil is solid waste generated from the dredging of a river. It exhibits low bearing capacity and high compressibility and poses severe health and environmental problems. Due to rapid urbanisation and unavailability of suitable construction sites, soft soil deposits are being improved for utilisation either as construction material or foundation medium. In this context, this study researched dredged soil samples collected from flood spill channel of Jhelum River Srinagar for characterisation of physical and engineering properties as per standard Codal procedures. Based on experimental investigations, test results revealed that the dredged material exhibit properties similar to in situ soil, not suitable as construction material. The weakest sample was chosen for cement treatment of dredged soil for its bulk utilisation as an engineered construction material. The index and engineering properties of the dredged soil were improved using cement at varying percentages of 4, 8, 12 and 16% of dry weight of soil. Consistency limits, compaction characteristics and shear strength parameters of treated soil samples were studied. The test results revealed that the unconfined compressive strength increased significantly with increasing cement content and curing period. The optimum value of cement content was observed at 12% beyond which the strength decreased. The cementitious compounds formed due to pozzolanic reactions filled the void spaces and enhanced the strength behaviour of cement treated dredged soil.