The Potential Influence of Using Nanomaterials Additives on Unconfined Compressive Strength of Soft Soil

Abstract

The building constructed on soft soils may fail due to their low strength, and an excessive settlement of the soil under a constant load could occur. Therefore, such soils must be improved before the construction eliminates or decreases the maintenance cost or collapse in buildings. Nowadays, nanoparticles are one of the modern materials that can be used in soil stabilization. The addition of soft particles such as nanomaterials may improve soil characteristics. This paper aims to clarify the influence of using conventional materials and nanomaterials on the unconfined compression strength of soft soil. Two types of nanomaterials (fly-Ash and silica fume) are selected as improvement additives. Curing times (0, 1, 3, 7, 14, 28 days) are taken as one of the influencing factors to study the variation in unconfined compression strength with the addition of nanomaterials. Nanomaterials in a tiny amount (5%) by dry weight of the soil (0.5, 1, 3, and 5%) are mixed to prepare the samples for unconfined compression test according to ASTM D 2166. The laboratory results show that the unconfined compressive strength of treated soil increases until reaching the optimum content of (3%) nanomaterials, then after that, these additives exhibit a negative effect on UCS. The strength of the mixtures with nanomaterial was higher than the strength of mixtures with ordinary materials. Also, the curing time has a considerable effect on the unconfined compressive strength from increases their magnitudes.