Behavior of Clay-Tire Mixtures Subjected to Undrained Monotonic Loading

Abstract

Soil - tire mixtures have been recently used as construction materials in civil engineering projects. In this research, a number of undrained triaxial tests were carried out on the compacted clay-tire mixtures and their behaviors were compared with behavior of pure clays. The results of the tests indicate that adding more than about 20%-30% tire to the low plasticity clay doesn’t reduce the shear strength in comparison with the associated values of pure clay. In the mixtures made of high plasticity clay, the shear strength decreases by increasing tire content. Moreover, friction angle and cohesion values vary with increasing tire-chips, which is completely dependent on the clay plasticity. The results also demonstrated that, for the mixtures of low plasticity clay, maximum excess pore water pressure occurs in the specimens with tire content of about 10%-20%. For the mixtures consist of high plasticity clay, at low consolidation stress, the pore water pressure decreases slightly with an increase in tire content. At high consolidation stress, excess pore water pressure induced within these mixtures increases slightly with an increase in tire-chips content. Adding tire-chips to the clay also lead to increase deformability of mixtures considerably.