摘要
装配式结构具有成本低、工期短和绿色施工等优点,因此中国正在大力推动装配式技术的应用.装配式技术应用于高速公路隧道建设中时,预制装配式仰拱与现浇衬砌接头处存在较大的安全隐患,容易发生剪切破坏.为了探究该类装配式结构接头处直剪受力状态下的抗剪力学性能,以接头的界面植筋率、界面尺寸和界面处理方式作为变化参数,设计并制作了21个“Z”字形试件开展直剪试验,观测了试件失效的全部过程以及破坏形态,获取了试件的剪切-滑移曲线,系统地分析了接头直剪力学性能的变化规律.结果表明:试件破坏分为植筋剪断和混凝土失效两种破坏形态;随着界面植筋率增加,试件极限抗剪承载力、延性和抵抗界面损伤演化的能力均随之提升;界面植筋率由0.7%增至1.1%时,极限抗剪承载力提升最大为66.4%;界面凿毛处理后试件的抗剪性能更优,其延性提升最大为41.5%;界面植筋率相同时,随着界面尺寸的增大,抗剪承载力随之提升,最大提升64.8%;试件抗剪性能存在一定的尺寸效应,界面尺寸较小试件的抗剪承载力随界面植筋率增加而提升的效果不显著.最后根据相关规范计算方法,基于试验结果和拓展的剪切-摩擦理论,提出了改进的预制装配式仰拱与现浇衬砌接头的抗剪承载力计算公式,计算值与试验值吻合度良好.
Owning to the advantages of prefabricated structures such as a low cost,a short construction period and green construction,the prefabricated technology is being vigorously developed in China.However,when this technology is applied to highway tunnel engineering,there will be a great potential safety hazard at the prefabricated assembly inverted arch to cast-in-place lining joint,which is prone to shear failure.To explore the shear performance of this kind of structural joint under direct shear stress,21 Z-shaped specimens were designed and fabricated to carry out direct shear tests,with the interface planting ratio of the joint,interface size and interface treatment method as parameters.The whole process and failure morphology of specimens were observed,their shear-slip curves were obtained,and the variation law of the direct shear mechanical properties of the joint was systematically analyzed.Results show that the failures of specimens can be divided into planting bars shear and concrete failure.With an increase in the interface planting ratio,the ultimate shear bearing capacity,ductility and damage resistance of specimens were all improved.When the interface planting ratio grew from 0.7% to 1.1%,the most significant improvement for the ultimate shear bearing capacity was 66.4%.The shear performance of specimens after the interface chiseling treatment was better,and the ductility of the chiseled specimen was maximumly improved by 41.5%.When the same interface planting ratio was kept,the shear bearing capacity was improved with an increase in the interface size,and the maximum improvement was 64.8%.There also existed certain size effect on the shear performance of specimens,and the shear bearing capacity of specimens with a smaller interface size did not increase obviously with the increase in the interface planting ratio.Finally,according to the relevant specification method and based on the test results as well as the extended shear-friction theory,an modified formula for calculating the shear bearing capacity o
作者
陈宗平
梁延
叶培欢
张士前
Chen Zongping;Liang Yan;Ye Peihuan;Zhang Shiqian(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China;China Construction Eighth Engineering Division Co.,Ltd.,Shanghai 200122,China)
出处
《天津大学学报（自然科学与工程技术版）》
EI
CAS
CSCD
北大核心
2024年第6期654-667,共14页
Journal of Tianjin University：Science and Technology
基金
国家自然科学基金资助项目(51578163)
八桂学者专项研究经费项目([2019]79号)
广西科技基地和人才专项(AD210750031)
中央引导地方科技发展资金项目(桂科ZY21195010).
关键词
预制装配式仰拱
衬砌接头
抗剪性能
抗剪承载力
prefabricated assembly inverted arch
lining joint
shear performance
shear bearing capacity
