USE OF GEOCELLS AS GROUND IMPROVEMENT TECHNIQUE TO IMPROVE TRAFFICABILITY IN DESERT TERRAIN

Abstract

Massive investments are underway to build and upgrade transportation infrastructure all across the globe, the challenges are more than budgetary. Marshy and soft soils which are predominant in coastal and border areas in India have peculiar characteristics. The shear strength of these marshy deposits is so low that even on walking they tend to liquefy. Poor soil conditions are generally the reason behind the lack of strength, and associated deformability. In such cases any kind of geotechnical construction is very difficult, as the consolidation settlement is going to be very high and also the permeability is very low. There are various methods for soil stabilization in such cases. Use of geocells is one of the most economical methods of soil improvement that is used to increase strength and reduces the liquefaction potential of soil. In recent times geocells are being widely employed in the field of geotechnical engineering for enhancing the bearing capacity of retaining structures, preventing erosion of slopes and river beds, reinforcing soft soil, etc. This report reviews the use of geocells in desert sand. In this research, results from a series of plate load test on geocell reinforced and unreinforced homogenous sand beds are presented. Large number of triaxial and direct shear tests were performed to get the soil strength parameters for both unreinforced as well as geocell reinforced surface. A number field tests were carried out in actual conditions in desert areas of Rajasthan. The study compares the field results using various load class vehicles including heavy load military vehicles on geocells with the experimental results and comes out with the fact that this technique increases the strength and stiffness property of sandy soil considerably and provides solution for preventing settlement and subsidence. It provides all round confinement to the material and thus prevents the lateral spreading of soil when load is applied. As a result of which higher loading is induced on the failure plane leading to enhanced load carrying capacity. Ease of construction, overall economy and less time consumption are major advantages of geocells. A cost comparison shows that use of geocell as reinforcement method is nearly 25% cheaper as compared to the conventional methods for track construction in deserts. This research work deals with study of overall mechanism, method employed and application of geocells in the field of civil engineering.