复杂应力状态下玻璃纤维再生混凝土损伤演变及应力-应变本构关系研究  

Study on Damage Evolution and Stress-Strain Constitutive Relationship of Glass Fiber Recycled Concrete Under Complex Stress State

作　　者：陈宇良[1,2,3] 王双翼 李洪 李培泽[1] CHEN Yuliang;WANG Shuangyi;LI Hong;LI Peize(School of Civil Engineering and Architecture,Guangxi University of Science and Technology,Liuzhou 545006,Guangxi,China;Guangxi Engineering Research Center for Safety Prevention and Control of Assembly Structure,Guangxi University of Science and Technology,Liuzhou 545006,Guangxi,China;Key Laboratory of Disaster Prevention&Mitigation and Prestress Technology of Guangxi Colleges and Universities,Guangxi University of Science and Technology,Liuzhou 545006,Guangxi,China)

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006 [2]广西科技大学广西装配结构安全防控工程研究中心,广西柳州545006 [3]广西科技大学广西高校防灾减灾与预应力技术重点实验室,广西柳州545006

出　　处：《材料导报》2024年第24期167-175,共9页Materials Reports

基　　金：国家自然科学基金(52368013,51908141);广西重点研发计划项目(桂科AB23075196);广西高校中青年教师科研基础能力提升项目(2022KY0348)。

摘　　要：本工作旨在通过常规三轴受压试验探究玻璃纤维再生混凝土(GFRAC)在三轴受压力学方面的性能,为此以玻璃纤维体积掺量V、再生粗骨料取代率γ和侧向围压σw为参数,共设计了168个100 mm(直径)×200 mm(高度)的玻璃纤维再生混凝土圆柱体试件并进行试验。通过试验获得了GFRAC的破坏特征并分析了不同参数对峰值应力、峰值应变及弹性模量的影响规律。由试验结果分析可得,随着侧向围压的增大,GFRAC的破坏形态由纵向劈裂破坏逐步转为斜向剪切破坏,网格状裂缝逐渐增多并布满试件,在试件的中部或端部出现“腰鼓”变形现象;通过施加侧向围压可以有效地增加GFRAC的峰值应力、应变和弹性模量;玻璃纤维提高了试件的峰值应力,且提高幅度在20%以内;增加再生粗骨料的取代率会导致峰值应力和弹性模量减小,最大下降幅度分别约为19.17%和34.91%,而峰值应变会增大,最大增幅可达76.77%;侧向围压和玻璃纤维均有效延缓了试件的损伤过程;最后,基于试验数据建立了玻璃纤维再生混凝土在三轴受压状态下的应力-应变本构关系。To explore the performance of glass fiber recycled concrete(GFRAC)in triaxial compression mechanics through conventional triaxial compression tests,here 168 glass fiber recycled concrete cylinder specimens of 100mm(diameter)×200mm(height)were designed with glass fiber volume content V,recycled coarse aggregate replacement rateγand lateral confining pressureσw as variable parameters.The failure characteristics of GFRAC specimens were obtained by experiments,and the influence of different parameters on peak stress,peak strain and elastic modulus was analyzed.The results showed that with the increase of lateral confining pressure,the failure mode of GFRAC gradually changed from longitudinal splitting failure to oblique shear failure,the grid cracks gradually increased and covered specimens,and the‘waist drum’deformation occured at the middle or end of the specimen.The peak stress,strain and elastic modulus of GFRAC could be effectively increased by applying lateral confining pressure.The glass fiber could enhance the peak stress of the specimen and the increased range was less than 20%.Increasing the replacement rate of recycled coarse aggregate resulted in the decrease of peak stress and elastic modulus,with the maximum decrease of 19.17%and 34.91%,respectively,while the peak strain increased with the maximum increase of 76.77%.Both lateral confining pressure and glass fiber should effectively delay the damage process of the specimen.Finally,based on the experimental data,the stress-strain constitutive relationship of glass fiber recycled concrete under triaxial compression was established.

关 键 词：三向复杂应力 玻璃纤维再生混凝土 力学性能 应力-应变本构关系 损伤分析 

分 类 号：TU528.58[建筑科学—建筑技术科学]