单裂隙岩石-混凝土组合体断裂特征颗粒流模拟  

Particle Flow Simulation of Fracture Characteristics of Rock-Concrete Combination with Single Crack

作　　者：李庆文 才诗婷 李涵静 钟宇奇 刘艺伟 LI Qingwen;CAI Shiting;LI Hanjing;ZHONG Yuqi;LIU Yiwei(School of Civil and Architectural Engineering,Liaoning University of Technology,Jinzhou 121001,Liaoning,China;School of Civil Engineering,Shandong Jianzhu University,Jinan 250101,Shandong,China)

机构地区：[1]辽宁工业大学土木建筑工程学院,辽宁锦州121001 [2]山东建筑大学土木工程学院,山东济南250101

出　　处：《高压物理学报》2024年第5期187-202,共16页Chinese Journal of High Pressure Physics

基　　金：辽宁省教育厅基本科研面上项目(JYTMS20230866);辽宁省自然科学基金(2023-MS-298,20180550297);辽宁省博士科研启动基金(2019-BS-120)。

摘　　要：为了研究不同长度及倾角的裂隙对岩石-混凝土组合体强度和破坏模式的影响,基于颗粒流模拟软件(PFC),通过对比预置裂隙试样的室内试验结果,选取最接近室内试验结果的一组数据标定细观参数,由此对含预置裂隙的岩石-混凝土组合体数值模型进行单轴压缩试验。结果表明:单裂隙岩石-混凝土组合体的承载能力和弹性模量随裂隙倾角的增大整体呈增大趋势,建立了不同裂隙长度和裂隙倾角的增量函数;裂隙长度对岩石-混凝土组合体力学特性的影响显著;岩石界面的应力状态和混凝土界面附近的约束效应决定裂纹能否扩展通过界面,根据裂纹的分布情况,分析发现裂纹萌生与扩展的根本原因是应力场的变化和转移,破坏过程中岩石-混凝土组合体的破坏模式由拉伸破坏逐渐转变成宏观剪切破坏,揭示了单裂隙岩石-混凝土组合体单轴压缩的损伤演化规律。To study the influence of cracks with varying lengths and inclination angles on the strength and failure modes of rock-concrete combination,a numerical model of rock-concrete combination with preexisting cracks was developed using the particle flow code(PFC).The model underwent calibration by comparing its results with indoor test data from prefabricated fractured specimens to select a set of microstructural parameters that closely align with the indoor test results.Subsequently,uniaxial compression tests were conducted on numerical models of rock-concrete composites containing pre-existing fractures.The results indicate that the bearing capacity and elastic modulus of fractured rock-concrete composites increase with the increase of fracture inclination angle.Moreover,functions were established to calculate the peak strength increment for fractures with varying lengths and inclination angles.The fracture length significantly influences the mechanical properties of composite models.The stress state at the rock interface and the confinement effect near the concrete interface determine whether cracks can extend through the interface.By analyzing the distribution of cracks,it was found that the fundamental reasons for crack initiation and propagation are the changes and transfers of the stress field.During the failure process,the failure mode gradually transitions from tension-dominated to macroscopic shear failure.The results reveal the damage evolution of uniaxial compression of single fissure rock-concrete combination material.

关 键 词：单裂隙 岩石-混凝土组合体 单轴压缩试验 裂纹演化 颗粒流 

分 类 号：O346.1[理学—固体力学] O521.9[理学—力学] TU45[建筑科学—岩土工程]