Interaction mechanism of Soil-ICB Grid

Abstract

To understand the improved behaviour of the Isometric Cogged Biaxial Grid (ICBG), this research is devoted to evaluating the factors affecting the soil-grid interaction by separating the effect of friction, shear, and passive resistance between the soil and grid. Laboratory pull-out tests are carried out using two types of soil (sand and crushed limestone) reinforced by three different types of reinforcements, which are; a Solid Plate, a Biaxial Grid and the ICBG. It is found that the ICBG, which is a biaxial grid modified by distributing cogs on both sides of its ribs, added a new factor to the resistance mechanism, which is the interlocking with soil aggregates. This factor comprises about 34% of the resistance value. Moreover, the design of the ICBG results in greater improvement in passive resistance and introduces interlocking between the ribs and the aggregates which raises the final passive resistance by about 50% over the traditional Biaxial Grid. It is also found that for the ICBG passive resistance and the shear strength comprise about 47% of the pullout resistance, while in the case of using the Biaxial Grid the shear resistance has the demonstrative role with more than 70%.