Polynomial models controlling strength of zeolite-cement-sand mixtures

The improvement of local soils with cement and zeolite can provide great benefits, including strengthening slopes in slope stability problems and stabilizing problematic soils to prevent soil liquefaction. Recently, dosage methodologies have been developed for improved soils based on a rational criterion as it exists in concrete technology. The present study aims to quantify the influence of the amount of cement, zeolite, porosity, and curing time in the evaluation of Unconfined Compressive Strength (UCS) of zeolite-cemented sand mixtures. A program of unconfined compression tests considering different voids ratios, cement contents, zeolite contents, and curing times was performed in this paper. The results show that UCS values of samples substantially increase with increasing zeolite content to an optimum value of 30% after 28 days of curing time. The rate of improvement is approximately between 20 to 80% and 20% to 60% for 28 and 90 days curing times, respectively. Moreover, the polynomial models are shown to be the appropriate ones to estimate UCS values of zeolite-cemented mixtures. Additionally, the sensitivity analysis reveals the influence of parameters and the contribution of each coefficient to the polynomial model. Cement and zeolite contents are related more strongly among relative density and curing time.