Dynamic Pore Pressure Responses of Sand–Rubber Tire Shred Mixtures from Cyclic Simple Shear and Cyclic Triaxial Tests

The cyclic simple shear tests best represent the in situ seismic stress conditions. However, cyclic triaxial tests are more popularly used. Also, the sand–rubber tire shred mixtures have recently gained research importance for their potential and possibility to act as seismic base isolation materials of buildings. The past studies could be found which deal with the dynamic properties such as the shear modulus and damping ratio of the sand–rubber tire shred mixtures. However, from the perspective of seismic isolation, it is necessary to study the pore pressure behavior of these mixtures. In view of the above, in the present study, the strain-controlled cyclic simple shear and cyclic triaxial tests are carried out on the weighed proportions of rubber tire shreds mixed with sand. The measured pore pressure responses from the both the cyclic tests are compared. It is found that the excess pore pressures generated in the cyclic triaxial testing are significantly higher than those developed during cyclic simple shear testing.