Posted on: 29 October 2019
In geotechnical engineering, soil properties play an integral role in determining the correct use of land for structures. Clay is one such soil type that geotechnical engineers have been studying for decades. The leaning tower of Pisa is a prime example of how clay soil properties affect structures stability. Consequently, significant advancements have been realised in clay soil geotechnical engineering. It is for this reason that the services of a geotechnical engineer are indispensable if you plan to build a facility on clay soil. This article looks at the various ways geotechnical engineering helps to stabilise clay soil.
One way geotechnical engineers stabilise clay soil is by adding cementitious materials deep into the ground. The additive material comprises several binding elements that mix with water to form a stabilising plastic paste. The endeavour is playing a critical role in reducing environmental degradation because the cementitious material used comes from electric power plants. Instead of disposing of the ash, it is collected by geotechnical engineers who add it to clay soil for deep soil mixing. Consequently, it improves the strength of clay soil as a foundation basis. Fly ash is a prime example of the type of cementitious material geotechnical engineers use to stabilise clayey soil.
Another material that geotechnical engineers use to stabilise clay soil with high effectiveness is lime. It might explain why slaked lime is the go-to material for supporting road bases as well as the sub-grade. By adding lime to clay soil, its plasticity index lowers, and this can be attributed to the pozzolanic action created by the mixture. Additionally, lime decreases the maximum compacted density and increases the strength and durability of clay soil. For clay soil, a 5% - 8% lime content is enough to achieve the desired strength. It is, however, common for geotechnical engineers to use foundation piles for additional strength.
Stabilisation With Geotextiles
Clay roads also need stabilising, but rather than use expensive techniques such as grouting and electrical stabilisation, geotextiles offer the perfect low-cost alternative. Geotechnical engineers thus rely on synthetic materials like polythene, polyester and polyvinyl chloride as geotextiles. The best part is that these fabrics can be used woven, non-woven or in grid form and still achieve the desired level of stability. However, the fabrics must be embedded in the clay soil correctly for effectiveness. Unpaved clay roads benefit the most from geotextile stabilisation since not much investment goes into the whole process.Share