绿片岩蠕变损伤本构关系研究

STUDY ON CREEP DAMAGE CONSTITUTIVE RELATION OF GREENSCHIST SPECIMEN

通过对绿片岩三轴蠕变试验数据的研究,分析绿片岩蠕变过程中衰减蠕变阶段、稳态蠕变阶段和加速蠕变阶段的各自特征,表明在蠕变加速阶段绿片岩的损伤在急剧增加。对于广义Bingham蠕变模型,在衰减和稳态蠕变阶段引入一非线性函数,在加速蠕变阶段引入损伤,建立绿片岩的蠕变损伤本构关系。通过岩石全自动流变伺服仪上得到的绿片岩流变数据来对新的蠕变损伤模型参数进行辩识,得到蠕变损伤模型的材料参数。蠕变损伤模型和试验结果相比较,发现该模型能够很好地描述蠕变曲线中初始的衰减蠕变阶段、稳态蠕变阶段和加速蠕变阶段,从而证明该模型的正确性和合理性。

Based on the study of triaxial creep curves of greenschist specimenst,he initial attenuation creep phase,the stabilization creep phase and the speedup creep phase of creep curve of greenschist specimen are analyzed.It is shown that the damage rapidly increases in the speedup creep phase.For the generalized Bingham creep model,a nonlinear function is introduced into the attenuation creep phase and the stabilization creep phase,and damage is introduced into the speedup creep phase;then,the creep damage constitutive equation of greenschist is created.The data obtained from rheological test on greenschist specimen on rock servo-controlling creep equipment are used to carry out the identification of the new creep damage model;and it can get the correlative parameters of the new creep damage model.Comparison between the results obtained from the creep damage model and the experiment shows that this model can well describe the initial attenuation creep phase,the stabilization creep phase and the speedup creep phase of the creep curve,which shows that the model is right and reasonable.