黏性土石混合体力学特性及破裂形态影响因素研究  

Study on influence factors of mechanical properties and fracture morphology of cohesive soil rock mixture

作　　者：蒋亚龙 汤新 朱碧堂 孙洋 俞俊平 胡逸凡 卢海峰[3] JIANG Yalong;TANG Xin;ZHU Bitang;SUN Yang;YU Junping;HU Yifan;LU Haifeng(School of Civil Engineering and Construction,East China Jiaotong University,Nanchang 330013,China;Jiangxi Transportation Research Institute Co.,Ltd.,Nanchang 330052,China;School of Civil Engineering and Architecture,Wuhan University,Wuhan 430072,China)

机构地区：[1]华东交通大学土木建筑学院,南昌330013 [2]江西省交通科学研究院有限公司,南昌330052 [3]武汉大学土木建筑工程学院,武汉430072

出　　处：《东南大学学报(自然科学版)》2025年第1期161-170,共10页Journal of Southeast University:Natural Science Edition

基　　金：国家自然科学基金资助项目(42267022,42377169);江西省自然科学基金资助项目(20232ACB214011,20232BCJ23004);江西省交通运输厅科技资助项目(2022Z0001,2022Z0002)。

摘　　要：为研究断层破碎带宏观力学效应及破裂形态的影响因素,以膨润土-水泥为骨料,配以拌和水,制备基质浆体,与块石混合制备黏性土石混合体,开展尺寸为500 mm×1000 mm的大型三轴压缩试验。研究结果表明,黏性土石混合体试样在各围压下均呈现出应变硬化特征,初始切线模量和峰值强度随着围压增加而逐渐增大。当块石体积含量P_(BV)≥0.4时,块石极易出现破碎现象,导致土石混合体的内摩擦角减小。块石倾角对试样强度的影响与含石量相关,P_(BV)=0.2时,0°倾角试样偏应力最小;P_(BV)=0.6时,60°倾角试样偏应力最小。较高围压条件下,不同倾角的块石旋转、移动呈现差异性,进而出现不同的破裂形态。研究成果揭示了断层破碎带的力学特性及破裂机制,为穿越断层破碎带的隧道稳定性控制提供了理论依据。In order to study the macroscopic mechanical effect of fault fracture zone and the influencing factors of fracture morphology,bentonite-cement was used as aggregate,mixed with mixed water to prepare matrix slurry,and mixed with block stone to prepare viscous soil-rock mixture.A large-scale triaxial compression test with the size of 500 mm×1000 mm was conducted.The results show that the sample of clay rock mixture presents strain hardening characteristics under various confining pressures,and the initial tangential modulus and peak strength gradually increase with the increase of confining pressure.Under the medium and high stone content(P_(BV)≥0.4),the stone is easily broken,resulting in the reduction of the internal friction angle of the soil-rock mixture.The influence of stone dip angle on sample strength is related to stone content.When P_(BV)=0.2,the bias stress of 0°dip angle sample is the smallest.When P_(BV)=0.6,the bias stress of the sample with 60°orientation angle is the smallest.Under high confining pressure conditions,the rotation and movement of stones with different orientation angles are different,and then different fracture forms appear.The research re-sults reveal the mechanical characteristics and fracture mechanism of the fault fracture zone,and provide a theoretical basis for the stability control of the tunnel through the fault fracture zone.

关 键 词：土石混合体 块石倾角 室内试验 含石量 破裂形态 

分 类 号：TU411[建筑科学—岩土工程]