Authors
1
Associate Professor of Engineering Geology, Faculty of Basic Sciences, Lorestan University, Khorramabad, Iran
2
Assistant Professor of Civil Engineering, Gonbad Kavoos branch, Islamic Azad University Gonabad Kavoos branch, Iran
3
Assistant Professor of Engineering Geology, Institute of Innovation, Science and Sustainability, Federation University, Ballarat 3350, VIC, Australia
4
Assistant Professor of Civil Engineering, Chaloos branch, Islamic Azad University, Chaloos, Iran
Abstract
Reinforcement can significantly reduce foundation settlement, but finding an economic plan requires detailed numerical studies. In the present study, the stability of granular soil reinforced with geogrid was analyzed using PLAXIS software and the effect of factors such as the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid on the of settlement were investigated. The results indicate that the factors mentioned above play a significant role in the foundation settlement. The analysis shows that by increasing the number and length of geogrid, the settlement value has decreased. Moreover, with the increase in the tensile strength of the geogrid, the settlement has significantly reduced. In regard the depth of the reinforced area, it was found that placing the first layer of geogrid after a certain depth (optimal depth) below the foundation does not cause a noticeable reduction in the settlement. Based on the output of PLAXIS software, the optimal values of the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid layer to minimizing the amount of settlement have been proposed. This can lead to a reduction in the costs of foundation design and implementation. According to the results, the lowest settlement (41 mm) was for the conditions where 5 layers of geogrid were used. The most optimal geogrid length and depth of the first geogrid layer to reduce the settlement is equal to 2.5 and 0.5 times the foundation width, respectively. Also, the lowest settlement (80.5 mm) for geogrid with tensile strength of 4500 kN/m was obtained. Finally, the accuracy of the results has been checked based on the modeling of actual data published by Laviza et al. (2010).
Keywords