基于3D打印的含复杂节理岩石直剪特性及破坏机制研究  

Research on direct shear behaviour and fracture patterns of 3D-printed complex jointed rock models

作　　者：王培涛[1,2,3] 黄正均 任奋华 章亮[1] 蔡美峰 WANG Pei-tao;HUANG Zheng-jun;REN Fen-hua;ZHANG Liang;CAI Mei-feng(Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mine,University of Science and Technology Beijing,Beijing 100083,China;Department of Civil,Environmental and Geo-engineering,University of Minnesota,Minneapolis,USA;Beijing Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083 [2]明尼苏达大学土木、环境与地质工程学院,美国明尼阿波利斯 [3]北京科技大学城市与地下空间工程北京市重点实验室,北京100083

出　　处：《岩土力学》2020年第1期46-56,共11页Rock and Soil Mechanics

基　　金：国家重点研发计划项目（No.2018YFE0101100）;国家自然科学基金项目（No.51604017,No.51774022）;中央高校基本科研业务费专项资金资助（No.FRF-TP-18-026A2）~~

摘　　要：岩体中节理的几何形态及力学特性是影响其剪切力学特性及破坏模式的重要因素之一。基于3D打印技术,建立了不同节理粗糙系数(JRC)的节理模型、几何形态节理模型和复杂裂隙网络物理模型,通过开展室内直接剪切试验分析了各组试件的剪切强度及破坏模式。结果表明节理模型的抗剪强度随JRC波动性较大,波动幅值越高,峰值剪切位移越低;平面形节理模型的峰值抗剪强度最低,矩形节理模型的峰值抗剪强度最高,正弦形和三角形节理试件的抗剪能力相近;离散裂隙网络模型和粗糙裂隙网络模型的峰值抗剪强度显著低于实心试件,考虑了节理粗糙性的裂隙网络模型抗剪强度高于直线型节理模型;实心试件破坏模式为典型脆性剪切破坏,裂隙网络模型的破坏模式相对复杂,沿着剪切方向主剪切裂面波动萌生,破断面由多个节理面的交叉点破坏与沿节理面的滑移构成。研究成果可以为3D打印技术的推广和复杂节理岩体剪切力学特性的室内试验研究提供参考。Geometry and mechanical characteristics of joints are key factors affecting the shear behaviors and fracture patterns of jointed rock mass.Using 3 D printing technique,experimental jointed rock specimens containing rough joints with varied joint roughness coefficient(JRC),different types of geometrical joints,and fractrues network were established respectively.Then direct shear tests were conducted on the jointed rock models to study the shear strength and failure patterns.The results show that the values of shear strength of jointed rock models fluctuate greatly with varied JRC curves.The peak shear displacement decreases with increasing amplitude of fluctuation.The lowest and highest values of shear strength are found in plane and rectangular joints,respectively.Moreover,the value of shear strength of sinusoidal type is found similar to that of triangular type.The shear strength of the 3 D-printed fractured rock specimens are apparently lower than that of the intact rock specimens.When considering joint roughness,the peak shear stresses of rough discrete fractures network(RDFN)models are higher than those of the discrete fractures network(DFN)models.The solid rock specimens exhibits typical brittle shear failure.The fracture patterns of DFN model and RDFN model are relatively complex and the main shear fractures are found along the shear direction.Meanwhile,certain intersection points between joints and certain surfaces have significant influence over the shear failures.The present work provides references for the application of 3 D printing technique in studying the shear behaviors of fractured rock masses.

关 键 词：节理岩体 3D打印 直接剪切 破坏模式 室内试验 

分 类 号：TU452[建筑科学—岩土工程]