摘要
为了研究不同压应力比和混凝土强度对地聚物珊瑚混凝土(geopolymer coral concrete,GCC)在压剪复合作用下力学性能和损伤演变的影响,进行了54个GCC试件的压剪试验,分析了试件的破坏模式、剪切荷载位移曲线和初始抗弯刚度,并着重分析了剪切承载力的组成及试件的损伤演化规律。结果表明:随着压应力比和混凝土强度增加,剪切强度及位移、初始剪切刚度均有所提高。剪切承载力包括黏聚力、界面摩擦力和骨料咬合力,黏聚力约占剪切承载力的11%~37%,界面摩擦力占比40%~67%,骨料咬合力占比16%~34%;界面摩擦力占比与压应力比呈正相关关系,黏聚力占比则相反。基于分段本构模型,对比试验数据和模型曲线发现两者拟合较好,验证了GCC的损伤本构模型与破坏模式有较高的预测精度。
To investigate the influence of varying compressive stress ratios and concrete strengths on the mechanical characteristics and damage progression of geopolymer coral concrete(GCC)subjected to combined compression-shear loading,a series of compression-shear tests were conducted on 54 GCC specimens.An analysis of the failure pattern,the shear load-displacement curve,and the initial flexural stiffness of the specimens was involved.Furthermore,it placed emphasis on analyzing the composition of shear bearing capacity and the evolving patterns of damage of the specimens.The results indicate a positive correlation between the shear strength,the displacement,and the initial shear stiffness with an increase in both compressive stress ratio and concrete strength.The shear bearing capacity comprises three key components:cohesive force,interfacial friction force,and aggregate occlusion force.Cohesion force contributes approximately 11%37%to the shear-bearing capacity,while interfacial friction force constitutes 40%67%,with aggregate occlusion force making up the remaining 16%34%.The proportion of interfacial friction demonstrates a positive correlation with the compressive stress ratio,while conversely,the proportion of cohesive force exhibits an inverse relationship.Utilizing a piecewise constitutive model,it is evident that there is a strong concordance between the experimental data and the model curve,which shows the high predictive accuracy of the damage constitutive model and failure pattern for GCC.
作者
杨海峰
杨青梅
柳岸然
YANG Haifeng;YANG Qingmei;LIU Anran(School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Nanning 530004,China;Guangxi Key Laboratory of Disaster Prevention and Structural Safety,Nanning 530004,China)
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2023年第6期1293-1303,共11页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金项目(52178123)
广西自然科学基金项目(2023JJA160233)
广西研究生教育创新项目(YCBW2023022)。
关键词
地聚物珊瑚混凝土
压剪复合作用
破坏模式
剪切强度
初始剪切刚度
损伤本构模型
geopolymer coral concrete
compression-shear loading
failure pattern
shear strength
initial shear stiffness
damage constitutive mode
