冻土非线性临界应变能释放率的测试方法

针对冻土材料的非线性特点,讨论了非线性临界应变能释放率GC的测试原理和方法,推导了相应的计算公式和参数确定的方法;然后给出了单边裂纹三点弯曲试样和单边“人”字切口试样的实验测试步骤和结果。结果表明,2种试样线弹性应变能释放率GC存在明显差别,但是,“人”字切口试样的GC与单边裂纹试样的GC*一致,说明非线性应变能释放率不强烈依赖于试样的类型。

Measured method of nonlinearity critical strain energy release rate of frozen soil

The measured technique and principle of nonlinearity GC were discussed,and an algorithm to estimate parameters of frozen soil was formulated.Single edge-through cracked specimens and single edge chevron notched specimens in three-point bending were used in the test,some preliminary results were given.The experimental results show that there exists obvious differences of the linear elastic critical strain energy release rate GC between the two specimens.But non linearity G*C of the straight-through cracked specimens and GC of the chevron-notched specimens are accordahce well,which are not so strongly dependent on specimen types and crack preparation.