Results in Engineering (Dec 2024)
Investigating the geomechanical behavior and mechanism of clay stabilization with natural zeolite and nano-magnetite under accelerated curing conditions (ACC)
Abstract
Chemical stabilization is a commonly used technique for ground improvement. Traditional methods of chemical soil stabilization rely on additives such as cement and lime, which are relatively expensive and not environmentally friendly. Therefore, using accessible natural pozzolans, such as zeolite, in soil stabilization is an effective and economical option. This study investigated the effect of zeolite and nano-magnetite on the geomechanical behavior of fine-grained clayey soil. Unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV), and electrical conductivity (EC) tests were performed on both stabilized and unstabilized samples. The samples were cured under standard curing conditions (SCC) and accelerated curing conditions (ACC). The UCS and UPV results for the clay sample containing 5% zeolite and 1% nano-magnetite showed significant increases of 85% and 48% under SCC and 174% and 59% under ACC, respectively, compared to untreated clayey soil. Additionally, the clay mixture containing 5% zeolite and 1% nano-magnetite, which achieved the highest UCS and UPV values under ACC, exhibited increases of 166 kPa and 100 m/s, respectively, compared to SCC. Moreover, the EC value decreased by approximately 51% and 60% for the samples with the highest strength in SCC and ACC, respectively. Based on Scanning Electron Microscope (SEM) imaging and Energy Dispersive Spectroscopy (EDS) analysis, the impact of zeolite and nano-magnetite on improving compaction and promoting hydrothermal reactions was evident, supporting the higher geomechanical results obtained. Overall, the findings suggest that using zeolite and nano-magnetite offers a cost-effective and eco-friendly solution for stabilizing clayey soil in civil engineering projects.
