黏土-混凝土组合体强度及全过程统计损伤模型  

Strength and statistical damage model in whole process of clay-concrete combined body

作　　者：李怀鑫 晏长根[1] 林斌[2] 石玉玲[3] LI Huai-xin;YAN Chang-gen;LIN Bin;SHI Yu-ling(School of Highway,Chang'an University,Xi'an 710064,China;School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;School of Geological Engineering and Geomatics,Chang'an University,Xi'an 710054,China)

机构地区：[1]长安大学公路学院,西安710064 [2]安徽理工大学土木建筑学院,安徽淮南232001 [3]长安大学地质工程与测绘学院,西安710054

出　　处：《吉林大学学报(工学版)》2025年第1期245-255,共11页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金项目(42077265);甘肃省交通运输厅科技项目(2021-19)。

摘　　要：为研究不同影响因素下小倾角(0°<θ<30°)接触面对桩-土复合结构强度特性的影响,通过TSZ-2全自动三轴仪进行变倾角组合体三轴不固结不排水试验,探讨了黏土-混凝土组合体在不同围压和含水率条件下的抗剪强度及破坏机理,并根据小倾角组合体试样的剪切特性推导出全过程统计损伤模型。研究结果表明:当组合体试样接触面倾角为0°<θ<30°时,且土样含水率为17%时,适当增大接触面倾角可提升组合体强度,而随着含水率的提高,组合体倾角越大,组合体强度越小;小倾角组合体试样三轴加载过程中的变形可分为接触面滑移阶段、试样弹性压缩与接触面剪切耦合阶段、土样弹塑性剪切阶段。变倾角组合体接触面倾角越大,初始损伤值越大,其总损伤值随应变的增加而增加,且总损伤值也受围压和含水率影响;将试验数据和模型理论值进行对比,结果表明:两者拟合度较为一致,验证了本文模型的准确性和合理性。In order to study the influence of small dip angle(0°<θ<30°)contact surface on the strength characteristics of pile-soil composite structure under different influencing factors,the unconsolidated undrained triaxial test on clay-concrete assembled specimens of variable inclination was carried out by TSZ-2 fully automatic triaxial instrument,and the shear strength and failure mechanism of the clay-concrete combined body under different confining pressures and moisture content were discussed.Finally,according to the shear characteristics of the small inclination clay-concrete combined body,the statistical damage model of the small-angle clay-concrete composite was deduced in the whole process.The results show that when the interface inclination of the clay-concrete combined body is 0°<θ<30°and the water content of the soil is 17%,increasing the interface inclination angle of the clay-concrete combined body can improve the shear strength,and as the water content gradually increases,the larger the interface inclination angle of the clay-concrete combined body,the smaller the shear strength of the clay-concrete combined body.The deformations during triaxial loading of the small-angle combined body can be divided into contact surface slip phase,specimen elastic compression and contact surface shear coupling phase,soil sample elastoplastic shear phase.The larger the inclination of the clay-concrete combined body,the bigger the initial damage value under the same conditions,besides,its total damage value increases with the increase of axial strain,and the initial damage value is also affected by the surrounding pressure and water content.Finally,the experimental data and theoretical values of the model are compared,and the overall fit is consistent,which verifies the accuracy and reasonableness of the model.

关 键 词：交通工程 变倾角组合体 三轴剪切试验 剪切机制 变形特性 统计损伤理论 

分 类 号：TU443[建筑科学—岩土工程]