考虑温度作用的岩石统计损伤本构模型及验证  

Statistical damage constitutive model for rocks considering temperature effects and its validation

作　　者：魏超 赵程[1,2] 赵春风[1,2] 松田浩 森田千寻 WEI Chao;ZHAO Cheng;ZHAO Chunfeng;MATSUDA Hiroshi;MORITA Chihiro(Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Geotechnical and Underground Engineering,Ministry of Education,Tongji University,Shanghai 200092,China;Department of Structural Engineering,Nagasaki University,Nagasaki 852-8521,Japan)

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]同济大学岩土与地下工程教育部重点实验室,上海200092 [3]长崎大学构造工学研究科,日本长崎852-8521

出　　处：《中南大学学报（自然科学版）》2024年第3期1056-1067,共12页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41572262,42142019)。

摘　　要：为了预测和评估深部高温岩体的稳定性,运用理论推导的方法研究温度作用下(后)岩石的本构关系。首先,基于已有的岩石统计损伤本构模型,考虑温度对岩石损伤变量的影响,引入了损伤变量修正系数、损伤起裂应力和起裂应变等参数;其次,假设微元体强度服从幂函数分布,并符合Hoek-Brown(H-B)强度准则,针对统计损伤本构模型无法反映峰前较强的微裂纹压密效应的弊端,引入了相应的模型修正系数;再次,建立了考虑温度作用的岩石统计损伤本构模型,并确定了模型参数的表达式;最后,对比不同温度作用下(后)的花岗岩在单轴和常规三轴压缩试验条件下所得的结果与文献中模型的计算结果,验证本文模型的准确性。研究结果表明:所提出的模型的计算结果与文献的试验结果在数值、分布规律和趋势上具有良好的一致性;对于全过程σ-ε曲线的各阶段,本文模型的计算效果较文献中本构模型计算效果更好,与试验曲线的贴合度更高,能够更好地反映高温作用下(后)岩石的损伤本构特征。该模型的参数具有常规性,适用于各类温-压组合作用工况下的岩石。In order to predict and evaluate the stability of deep high-temperature rock masses,theoretical derivation methods were used to study the constitutive relationship of rocks under(after)temperature action.Firstly,based on existing rock statistical damage constitutive models,the influence of temperature on rock damage variables was considered,and parameters such as damage variable correction coefficient,damage initiation stress,and initiation strain were introduced.Secondly,it is assumed that the strength of the microelements follows a power function distribution and conforms to the Hoek-Brown(H-B)strength criterion.In response to the drawback that statistical damage constitutive models cannot reflect the strong prepeak microcrack compaction effect,corresponding model correction coefficients were introduced.Thirdly,a rock statistical damage constitutive model considering temperature effect was established,and the expression of model parameters was determined.Finally,the accuracy of the model was verified by comparing the data obtained from uniaxial and conventional triaxial compression tests on granite under different temperature conditions with the calculation results of the model in the literature.The results show that the calculation results of the proposed model are consistent with the experimental results in literature in terms of numerical values,distribution patterns and trends.For each stage of the whole processσ−εcurve,the calculation result of the model in this paper is better than that of the constitutive model in the literature,and fits with the test curve better,which can better reflect the damage constitutive characteristics of rock under(after)high temperature.The parameters of the model are conventional and suitable for rocks under various temperature-pressure combination conditions.

关 键 词：岩石力学 幂函数 温度 HOEK-BROWN强度准则 微裂纹压密效应 本构模型 

分 类 号：TU45[建筑科学—岩土工程]