摘要
在地下洞室、隧道等工程中,裂隙岩石峰值强度后的损伤破坏特性及演化机制对控制围岩稳定至关重要,目前,对岩石峰后的损伤破坏特性研究不充分,认识不全面,易出现大体积塌方、大变形等工程事故。针对峰后裂隙岩石的力学性质,开展室内三轴试验,分析其非线性损伤破坏特性;假设岩石损伤满足Weibull分布规律,引入损伤变量,推导出峰后裂隙岩石非线性损伤破裂本构方程;将上述本构方程与能量耗散原理、应变能密度理论相结合,建立了峰后裂隙岩石的非线性损伤破坏准则;采用FISH语言开发了基于上述破坏准则的峰后岩石损伤破裂计算程序,用连续的方法模拟分析了峰后裂隙岩石的非连续损伤破裂过程,揭示了裂隙岩石峰后损伤破坏特性及其演化规律,并与裂隙岩石的三轴压缩试验结果进行了对比。结果表明:上述本构方程与判别准则能较好地模拟峰后裂隙岩石非线性损伤破裂过程。为有效控制围岩稳定提供一种新的理论分析手段。
Damage characteristics and damage evolution mechanism of post-peak fractured rock mass are critical for controlling the stability of surrounding rock in underground caverns, tunnels and other rock engineerings. Since the current study on damage and destruction characteristics of post-peak fractured rock mass is insufficient, and its understanding is not comprehensive, the potential engineering accidents may occur, such as large collapse and large deformation. In this study, a series of triaxial tests was carried out to investigate mechanical properties of the post-peak fractured rock mass. Then, the corresponding nonlinear damage characteristics were analyzed. Assuming that the rock damage satisfies the Weibull distribution rule, a constitutive equation of the fractured rock was deduced by introducing a damage variable. A nonlinear damage and failure criterion of post-peak fractured rock was established by combining with the energy dissipation principle and strain energy density theory. Based on the above principle, the calculation program of damage failure of post-peak rock was developed according to FISH language, and the simulation of the non-continuous process of post-peak fractured rock was realized using a continuous method. As a result, the damage and failure characteristics and its evolution rule of post-peak fractured rock mass were revealed. Furthermore, numerical results were compared with triaxial compression results. It turns out that the constitutive equation and the discriminant criterion can well simulate the nonlinear damage and rupture process of fractured rock. Therefore, this study can provide a new theoretical analysis method to effectively control the stability of surrounding rock.
作者
谢璨
李树忱
平洋
李景龙
李术才
XIE Can LI Shu-chen PING Yang LI Jing-long LI Shu-cai(Geotechnical and Structural Engineering Research Center, Shandong University, Jinan, Shandong 250061, China China State Construction Technical Center, Beijing 101300, China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2017年第7期2128-2136,共9页
Rock and Soil Mechanics
基金
国家自然科学基金面上项目(No.51379113
No.51134001)
教育部高等学校博士学科点博导类专项科研基金(No.20120131110031)
山东省杰出青年基金(No.201313JQE27042)
山东省自然科学基金资助(No.ZR2013EEQ023)~~
关键词
非线性损伤
应变能密度理论
峰值强度后
数值模拟
nonlinear damage
strain energy density theory
post-peak strength
numerical simulation
