Effect of Position and Innovative Geocomposite Mat Number Layers on California Bearing Ratio of Problematic Soil

Abstract

Geosynthetic technology is one of the potential materials widely used in geotechnical engineering applications such as soil reinforcement, slope stabilization and soil filtration. The California Bearing Ratio (CBR) test was used in Malaysia to assess the performance of subbase soil for road construction. An experimental investigation was carried out in this work to assess the performance of reinforced kaolin clay by adding a layer of Innovative Geocomposite Mat (IGM) at various position and multiple layers. The CBR tests were evaluated on the soil by placing IGM at different positions (h/2, h/3 and 3h/4) and the different number of layers (1-layer, 2-layer and 3-layer). Through a series of CBR tests in the laboratory, the optimum position and number of reinforcement layers were determined. The result demonstrates a considerable contribution in terms of higher CBR value of reinforced kaolin clay, resulting in a lowered design of subbase thickness. It has been observed that the position at h/2 performs better than h/3 and 3h/4 for a single layer of IGM. When compared to unreinforced kaolin clay, the CBR value of 0.5H has risen by 25%. The result indicates that for the maximum benefit, IGM should be placed for a 2-layer between 0.3H and 0.6H of the height of the soil specimen. In contrast with unreinforced kaolin clay, the CBR value has improved dramatically to 54.54%. The excellent properties of the IGM provide manifold benefits in the improvement of soil bearing capacity and the thickness of the soil can be reduced.