Creep damage constitutive model of rock based on the mechanisms of crack-initiated damage and extended damage  

作　　者：Tianbin Li Chao Chen Feng Peng Chunchi Ma Mou Li Yixiang Wang 

机构地区：[1]State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China [2]College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China [3]School of Urban Construction,Chengdu Polytechnic,Chengdu 610218,China [4]Shudao Investment Group Co.,Ltd,Chengdu 610094,China

出　　处：《Underground Space》2024年第5期295-313,共19页地下空间（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.U19A20111 and 42130719);the State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection Independent Research Project(Grant No.SKLGP2017Z001)。

摘　　要：Since the classical element model cannot describe the nonlinear characteristics of rock during the entire compressive creep process,nonlinear elements and creep damage are generally introduced in the model to resolve this issue.However,several previous studies have reckoned that creep damage in rock only occurs in the accelerated creep stage and is only described by the Weibull distribution.Nevertheless,the creep damage mechanism of rocks is still not clearly understood.In this study,a reasonable representation of the damage variables of solid materials is presented.Specifically,based on the Gurson damage model,the damage state functions reflecting the constant creep stage and accelerated creep stage of rock are established.Further,the one-dimensional and three-dimensional creep damage constitutive equations of rock are derived by modifying the Nishihara model.Finally,the creep-acoustic emission tests of phyllite under different confining pressures are conducted to examine the creep damage characteristics of phyllite.And the proposed constitutive model is verified by analyzing the results of creep tests performed on saturated phyllite.Overall,this study reveals the relationship between the creep characteristics of rocks and the corresponding damage evolution pattern,which bridges the gap between the traditional theory and the quantitative analysis of rock creep and its damage pattern.

关 键 词：ROCK Creep damage Constitutive model Damage state function Indoor tests 

分 类 号：U45[建筑科学—桥梁与隧道工程]