In order to obtain the influencing factors and behavior of the intrinsic length of clay in Tianhe District of Guangzhou, different specimens are fabricated by the mixing clay and quartz sand in Tianhe District. Using the triaxial shear test results, the intrinsic lengths of different samples are determined. The results show that the liquidity index of matrix has little effect on the intrinsic length. The intrinsic length increases linearly with increasing reinforcing particle content. The larger the content is, in reinforcing particle the larger the decrease is in intrinsic length. The intrinsic length decreases with increased reinforcing particle size.
