考虑基体变形和微凸体变形相互作用的岩石节理闭合变形理论模型  

Theoretical closure model for rock joints considering interaction of deformations of substrate deformation and asperity

作　　者：唐志成 黄润秋[2] 焦玉勇[1] 谭飞 朱星[2] TANG Zhi-cheng HUANG Run-qiu JIAO Yu-yong TAN Fei ZHU Xin(Faculty of Engineering, China University of Geosciences, Wuhan 430074, China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [3]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《岩土工程学报》2017年第10期1800-1806,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金面上项目(41672302;11672360;41402247);地质灾害防治与地质环境保护国家重点实验室开放基金项目(SKLGP2014K018)

摘　　要：地下岩体工程建设和运营过程中,需要考虑节理岩体的水力学性质,这与节理的闭合变形密切相关。对法向应力作用下节理微凸体的变形特征进行详细分析,逐个计算接触微凸体的法向变形和接触应力;采用接触理论计算微凸体基圆半径之外的基体变形,并以此调整微凸体的法向位置,进而提出新的闭合变形理论模型。新模型可反映节理的基体变形和微凸体变形相互作用的影响,也能体现形貌分量和接触类型对闭合变形的影响。与已有的理论模型比较,新模型的计算值更为接近试验值。采用叠加原理,新模型计算得到的初始法向刚度最小;但随法向应力的增加,法向刚度增加速率逐步加快。The closure behavior of rock joints remains a problem of interest with applications in many practical engineering cases. Based on a comprehensive assessment of realistic closure behavior, a Hertz-based theoretical model is proposed to predict the closure behavior of a rock joint under compressive loading. In the present study, special attention is focused on the role of mechanical interaction of asperities during the closure process. The vertical positions（perpendicular to the least square plane） of asperities are adjusted by using the discrete methodology based on the Hertz solution of substrate deformation outside the contact region. The factors influencing the closure behavior of rock joints can be considered by the model, namely（1） the surface morphology component,（2） the contact state between the upper and lower blocks（or the composite topography）, and（3） the deformation due to asperity itself, the substrate deformation due to the deformed asperity and the deformation caused by the mechanical interaction due to the adjacent deformed asperities. The validity is demonstrated by comparing the experimental results with the curves predicted by Xia model, Tang model and the proposed model. The results show that the closure behavior predicted by the proposed model is in good agreement with experimental data, with small discrepancies between the predicted and the measured values. A preliminary explanation for the discrepancies of contact stiffness predicted by Xia model, Tang model and the proposed model associated with different underlying principles is also put forward.

关 键 词：岩石节理 闭合变形 接触力学 变形相互作用 

分 类 号：TU451[建筑科学—岩土工程]