膨胀性泥岩应力-应变关系的试验研究

通过应变控制式固结不排水三轴试验，测定并分析了膨胀性泥岩的应力-应变关系以及强度变化特性，结果表明，膨胀性泥岩的应力-应变曲线呈应变软化型，泥岩中的裂隙结构面等是影响泥岩强度的重要因素，说明了膨胀性泥岩不同的破坏模式对应着不同的应力-应变曲线；还说明了峰值强度、残余强度以及残余强度比是随围压的变化而变化的；孔隙水压力变化分为3个阶段。通过控制不同的剪切速率的固结不排水三轴试验，研究和分析了应变率对应力-应变关系、强度变化特性以及孔隙水压力的变化

Experimental study on stress-strain relationship of expansive mud-stone

Based on strain control consolidated undrained triaxial tests, stress-strain relationship and strength characteristic of expansive mud-stone are investigated and analyzed. The results show that the stress-strain relationship appears strain softening, and joints in mud-stone are important factor that influences strength characteristic. Different failure modes have different stress-strain relationships. Furthermore, the results also show that the peak strength, residual strength and residual strength ratio change with variation of confining stress, and development of pore pressure has three stages. By controlling shear speed ratio of triaxial test, influences of shear speed ratio on the stress-strain relationships and strength characteristic are discussed.