Reinforcement of Aeolian Sand by Perforated Geotextile for Road Foundations

Abstract

Roads are one of the most important infrastructures in the modern world. These are built for social, strategic, urban and economic purposes. Dune sand is available at a low cost throughout the North African Sahara, but it is rarely used as a construction material. In addition, the scarcity of noble materials used in road pavement has led to search for other alternatives, such as dune sand. The purpose of this study is to exploit the abundant aeolian sand by reinforcing it with perforated geotextile for use in road foundation layers. The use of perforated geotextile is to enhance its entanglement with the sand and reduce the amount required. This study also aims to evaluate the bearing capacity (CBR) of the sand/geotextile compound. The sand was tested alone using the CBR test and then with the addition of a geotextile layer. This study involves creating holes with varying diameters and spacing between them in order to evaluate the effect of perforating the geotextile on the bearing capacity of the reinforced sand. The results of the experimental tests demonstrate a significant increase in the bearing capacity of the compound (sand/geotextile) as measured by the CBR index. This index increases up to four times that of sand alone and reaches 84.7% of that of a tuff commonly used in the study region. The amount of geotextile used is reduced by up to 50.24%. Regression analysis provided an empirical relationship between the bearing capacity (CBR) of the compound, the grain size of the sand, and the perforation pattern of the geotextile. This contributes to the indirect evaluation of the CBR index of the composite material.