Improving shallow foundations resting on saturated loose sand by a zeolite-cement mixture: A laboratory study

Improvement of sands is frequently carried out by cement together with several other additives. The common additives have high manufacturing costs and negative environmental impacts during their manufacturing process and recycling in nature. Zeolite as a mineral substance for cement replacement can improve the strength parameters of a treated sand, without the negative deficiencies of the common additives. In this study, unconfined compression strength (UCS) and small-scale 1g model tests were conducted to evaluate the mechanical features of zeolite-treated sand and to study the behavior of shallow foundations rested on zeolite pad, respectively. The results of this study demonstrate that the UCS of the cemented sand samples increase when the cement is replaced by zeolite at an optimum proportion of 40% with 14 and 28 days curing times. Adding this amount of zeolite to cemented sand mixture causes an increase in terms of the improvement rate between 40% and 125% and increases the bearing capacity ratio (BCR) of the strip foundation treated by zeolite pad in the range of 11% and 420%. In addition, zeolite pad leads to decline the settlement of the treated strip footing from 16% to 86% in terms of the settlement reduction ratio (SRR).