Prediction of UCS and CBR Values of Cement Stabilised Mine Overburden and Fly Ash Mixture

Abstract

Mine wastes are generally known as mine overburden, which are removed during surface mining. Utilization of this mine overburden will reduce environmental impact and availability of land resource in coal mining area. Indian coal produces vast amount of fly ash during generation of power every year less than 50% of it being used. Many a places, the thermal power plants are close to the coal mines. In such places, a mixture can be prepared by using fly ash, coal mine overburden with or without cement which can be used as a stabilized material. The amount of cement used in mixture is varying from 4-7%. In the present study, the feasibility of mine overburden mix for use as pavement material has been examined by measuring the unconfined compressive strength (UCS) and California Bearing ratio (CBR) of the mix in the laboratory. Based on the UCS and CBR values of the stabilized mixture, it was inferred that it can be used as a stabilized pavement material. Moreover, an attempt has been made to develop prediction models using Artificial Neural Network (ANN), group method of data handling (GMDH) and Multiple Linear Regression (MLR) that can be used in the field by practicing geotechnical engineers to calculate the expected UCS and CBR value of fly ash, mine overburden and cement mix. It was found that the GMDH model was better than MLR and ANN in terms of statistical criteria.