红山窑红砂岩膨胀变形和软化特性试验研究

以南京红山窑水利枢纽工程所提供的基岩红砂岩岩芯为例,采用MTS815.02型岩石刚性伺服试验系统和岩石膨胀测量仪,对风化红砂岩进行膨胀变形及力学特性试验研究.试验结果表明:红砂岩膨胀应变随吸水率增加而呈对数增长,红砂岩弹性模量、抗压强度随吸水率增加而呈对数减小,而泊松比随吸水率增加而呈对数增大,由于含水率的变化使膨胀岩发生了显著的软化现象.研究成果为工程地基稳定性分析提供了可靠的理论依据.

Test study on expansive and softtening characteristic of red sandstone in Hongshanyao

By using Rock Mechanics Rigidity Servo Testing System (RMTS815.02) and Rock Odometer, the swelling behaviour of red sandstone from a foundation pit of Hongshanyao Project (HSYP) in Nanjing, is tested and studied. The experimental results show that the curve of expansive strain-percent sorption is a logarithm, and the modulus of elasticity and compressive strength of red sandstone reduce with logarithm with the increase of water content. On the contrary, the poisson's ratio increases with logarithm with the increase of percent sorption. Due to the changes of percent sorption, the swelling rock are remarkably softened. Doubtless, the research results can be the theoretic basis for the stability analysis of engineering foundation.