Thermo-mechanical responses of saturated silty soil to undrained heating-cooling cycles

The thermal-mechanical responses of saturated silty soil to heating-cooling cycles under undrained condition are discussed. The test results show that the variation tendency in the temperature of a specimen is almost consistent with each other in each period of repeated thermal loading, which is independent of confining pressure and cyclic number. The pore pressure increases gradually with the rise in the temperature of the specimen, and furthermore the variation tendency of pore pressure is also similar in each period. Under the same confining pressure, the normalized maximum pore pressure increases as the number of repeated thermal loading increases. In the process of temperature dropping, as the repeated number increases, the normalized pore pressure seems to descend more slowly, while the normalized residual pore pressure increases. Besides, the normalized pore pressure shows a decreasing tendency with the increase of confining pressure. As the temperature increases, the volume of the specimen increases due to the expansion of solid grains and pore water. When the temperature descends, the volume of the specimen begins to decrease gradually and tends to be zero.