高温后钢纤维混凝土压-剪复合受力研究  

RESEARCH ON THE COMPRESSIVE SHEAR COMPOSITE STRESS OF STEEL FIBER REINFORCED CONCRETE AFTER HIGH TEMPERATURES

作　　者：尹海旭 高立堂[1] YIN Haixu;GAO Litang(Civil Engineering,Qingdao University of Technology,Shandong Qingdao 266520,China)

机构地区：[1]青岛理工大学土木工程学院,山东青岛266520

出　　处：《低温建筑技术》2024年第2期100-105,共6页Low Temperature Architecture Technology

摘　　要：为研究高温后钢纤维混凝土压剪复合受力下的力学性能,以压应力比和温度作为参数,对20组钢纤维混凝土分别开展直剪试验和压剪试验,对比分析不同试件的破坏形态,探究了温度和压应力比对剪切强度的影响,并基于3种理论建立了高温后钢纤维混凝土压剪复合应力状态下的破坏准则。结果表明压剪复合受力状态下,混凝土剪切强度主要由接触摩阻力贡献,钢纤维混凝土峰值剪切强度随压应力比增大而增大,随温度升高而降低;随着压应力增大,剪切面上摩阻系数降低,峰值剪切强度增长幅度降低。依据试验数据,对比基于不同理论所建立的高温后钢纤维混凝土压剪破坏准则,考虑精确度和适用性,基于应力不变理论建立的破坏准则效果最好。This paper studies the steel fiber reinforced concrete(SFRC)after high temperature compressive shear composite mechanics performance under loading.Taking compressive ratio and temperature as the independent variable,20 SFRC samples are carried out direct shear tests and shear tests.The failure forms of different SFRC specimens are compared and analyzed,and the effectiveness of temperature and compressive stress ratio on shear strength is investigated.Based on three theories,the failure criterion of SFRC under combined compressive shear loading after high temperature is established.The results indicate that SFRC shear strength is mainly composed of contact friction force contribution in the state of combined compressive shear loading.With the compressive stress ratio increases,the peak shear strength of SFRC also increases,which decreases with the increase of temperature.With the increase of compressive stress,the friction coefficient on the shear plane exhibits a decrease,and the growth amplitude of the peak shear strength decreases.According to the testing data,the compressive shear failure criterias established based on different theories after high temperature SFRC are compared.Considering the accuracy and applicability,the failure criterion established based on the stress invariant theory is with the best effectiveness.

关 键 词：钢纤维混凝土 压剪复合受力 混凝土剪切强度 

分 类 号：TU528.57[建筑科学—建筑技术科学]