无腹筋混凝土受弯构件基于力学分析的受剪计算  

Shear Capacity Prediction for RC Beams Without Stirrups Based on Mechanical Research

作　　者：熊二刚[1] 祖坤 胡勤斌 张倩[3] 梁兴文[4] XIONG Ergang;ZU Kun;HU Qinbin;ZHANG Qian;LIANG Xingwen(School of Civil Engineering,Chang’an University,Xi’an 710061,Shaanxi,China;School of Civil Engineering,Southeast University,Nanjing 211189,Jiangsu,China;School of Human Settlements and Civil Engineering,Xi’an Euraisa University,Xi’an 710065,Shaanxi,China;School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,Shaanxi,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061 [2]东南大学土木工程学院,江苏南京211189 [3]西安欧亚学院人居环境学院,陕西西安710065 [4]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《华南理工大学学报（自然科学版）》2022年第11期115-124,132,共11页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51808046);陕西省重点研发计划项目(2021SF-461)。

摘　　要：从无腹筋混凝土梁构件临界破坏斜截面出发,分析临界破坏斜截面上的各部分受力,通过理论推导与合理简化,确定计算参数的取值,建立了基于力学分析的无腹筋混凝土梁受剪承载力计算模型。该模型基于经典力学原理,具有明确的物理意义,能够较好地反映混凝土强度、剪跨比、纵筋配筋率等受剪参数以及尺寸效应的影响。然后,基于9根试验梁试件的剪切试验数据对比评估了基于力学分析的计算模型和现行的中美欧日等国家和地区的规范及Zsutty计算公式的预测精度和稳定性。最后,对该公式在无腹筋FRP筋混凝土梁受剪承载力计算的适用性进行了验证。结果表明:基于力学分析的受剪分析模型能够较好地预测无腹筋混凝土梁的受剪承载力,真实地反映梁斜截面剪切破坏机理;具有较高的预测精度和良好的稳定性,可以较好反映受剪承载力与剪跨比及纵筋配筋率之间的非线性变化关系;且随参数变化预测结果具有一致稳定性,对无腹筋FRP筋混凝土梁受剪承载力计算具有很好的适用性。Starting from the critical failure inclined section of reinforced concrete beam without stirrups, this study analyzed the force of each part on the critical failure inclined section. Through theoretical derivation and rational simplification, the value of calculation parameters was obtained, and the calculation model of shear capacity of based on mechanical balance for the reinforced concrete beam without stirrups. On the basis of the classical mechanics principle, the model has a clear physical meaning and can better reflect the influences of shear parameters including concrete strength, shear-span ratio, longitudinal reinforcement ratio and size effect, respectively. Then,the prediction accuracy and stability of the proposed shear model were evaluated based on 9 test specimens by comparing with the GB 50010—2010, ACI 318-14, EC 2, JSCE 2007 and Zsutty calculation formula. Finally, the applicability of the proposed model in the calculation of shear capacity of FRP reinforced concrete beams without stirrups was verified. The results show that the proposed model based on mechanical balance can effectively predict the shear capacity of reinforced concrete beams without stirrups and exhibit the shear failure mechanism of beam oblique section. Moreover, the proposed shear model has a higher prediction accuracy and stability, and can better reflect the nonlinear relationship between shear capacity versus shear-span ratio and longitudinal reinforcement ratio. In addition, the predicted results have a consistent stability with the change of shear parameters, so it can be applied to the shear capacity calculation of FRP reinforced concrete beams without stirrups.

关 键 词：无腹筋混凝土梁 力学分析 剪切试验 受剪承载力 预测精度 

分 类 号：TU375.1[建筑科学—结构工程]