配置高强网格式间接钢筋的RPC局压承载力试验研究  

Experimental study on local compressive capacity of RPC with high strength mesh transverse reinforcement

作　　者：樊梦玫 郑文忠[1,2] 李胜[1,2] 王英[1,2] FAN Mengmei;ZHENG Wenzhong;LI Sheng;WANG Ying(Key Lab of Structural Dynamic Behavior and Control,Ministry of Education,Harbin Institute of Technology,Harbin 150090,China;Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters,Ministry of Industry and Information Technology,Harbin Institute of Technology,Harbin 150090,China)

机构地区：[1]哈尔滨工业大学结构工程灾变与控制教育部重点实验室,黑龙江哈尔滨150090 [2]哈尔滨工业大学土木工程智能防灾减灾工业和信息化部重点实验室,黑龙江哈尔滨150090

出　　处：《建筑结构学报》2023年第2期227-238,共12页Journal of Building Structures

基　　金：国家自然科学基金项目(51678190);黑龙江省“头雁”计划(2019-49)。

摘　　要：为得到配置高强网格式间接钢筋的活性粉末混凝土(reactive powder concrete, RPC)局压承载力计算公式,对10个配置网格式间接钢筋(从楔形体侧面外伸并弯折后满足受拉锚固长度要求)的RPC开展局压试验。RPC局压面积比为4.34,主要参数包括RPC轴心抗压强度(88、104.8 MPa)、网格式间接钢筋抗拉强度标准值(800、970、1 270 MPa)、间接钢筋体积配筋率(0.9%~1.5%)。试验结果表明:RPC发生局压破坏时,均在局压影响区产生四角锥楔形体,劈尖夹角约53°~61°;随着RPC强度等级、间接钢筋强度等级的提高,间接钢筋拉应力(340~550 MPa)逐渐减小,且小于间接钢筋比例极限。收集33个RPC轴心抗压强度介于74~110 MPa、局压面积比介于1.4~9的未配置间接钢筋的RPC的局压承载力试验数据,对未配置间接钢筋的RPC局压承载力影响因素进行参数分析,发现未配置间接钢筋的RPC局压承载力与局压面积比及轴心抗压强度有关。根据试验结果及收集数据可知:配置高强网格式间接钢筋的RPC局压破坏时,间接钢筋不易发挥作用,RPC对局压承载力的贡献远大于高强网格式间接钢筋;随着RPC及间接钢筋材料强度等级的提高,局压破坏时间接钢筋拉应力逐渐减小,使间接钢筋充分发挥作用的体积配筋率下限值逐渐上升,工程实践中仍需对RPC局压承载力进行合理计算。基于未配置间接钢的RPC局压承载力计算公式、配置间接钢筋RPC试件局压破坏时间接钢筋拉应力计算公式,提出了配置高强网格式间接钢筋的PRC局压承载力计算公式。试验所得实测值与计算值吻合良好,适用范围为活性粉末混凝土强度90~130 MPa、高强网格式间接钢筋屈服强度800~1 300 MPa。In order to obtain the formula for calculating the local compressive bearing capacity of reactive powder concrete(RPC) with high strength mesh transverse reinforcement, local compressive test was carried out on 10 RPC specimens with mesh transverse reinforcement(extending from the side of the wedge and bending to meet the requirements of tensile anchorage length). RPC local pressure area ratio is 4.34, the main parameters are: RPC axial compressive strength(88、104.8 MPa), standard value of tensile strength of mesh transverse reinforcement(800、970、1 270 MPa), volume reinforcement ratio of transverse reinforcement(0.9%-1.5%). The results show that: when the 10 RPC specimens tested were damaged under local pressure, all of them produce pyramid wedges in the local compressive influence area, wedge angle 2θ is about 53°-61°, with the increase of RPC strength grade and transverse reinforcement strength grade, the tensile stress of transverse reinforcement(340-550 MPa)gradually decreases, which is less than the proportional limit of reinforcement. The local compressive bearing capacity test data of 33 RPC specimens with RPC axial compressive strength between 74-110 MPa and local pressure area ratio between 1.4-9 without reinforcement were collected, the influence factors of RPC local compressive capacity without reinforcement were studied. It is found that the local compressive capacity of RPC without reinforcement is related to local pressure arearatio and axial compressive strength. According to the test results and collected data: when RPC with high strength mesh transverse reinforcement is damaged by local compressive, the reinforcement is not easy to play a role, the contribution of RPC to the local compressive capacity is much greater than that of high strength mesh transverse reinforcement. With the improvement of RPC strength grade and reinforcement strength grade, the tensile stress of the reinforcement decreases gradually during the local compressive failure time, and the lower limit of the volume rei

关 键 词：活性粉末混凝土 钢筋锚固 局压试验 局压承载力 间接钢筋拉应力 体积配筋率下限值 

分 类 号：TU375[建筑科学—结构工程]