超高性能砂浆砌体短柱轴压试验  

Axial compression test of masonry short columns with ultra-high performance mortar

作　　者：黄卿维[1] 廖妙星 陈宝春[1] 卢绍斌 刘君平[1] 李聪 黄文金 黄新艺[1] HUANG Qing-wei;LIAO Miao-xing;CHEN Bao-chun;LU Shao-bin;LIU Jun-ping;LI Cong;HUANG Wen-jin;HUANG Xin-yi(College of Civil Engineering,Fuzhou University,Fuzhou 350108,Fujian,China;College of Transportation and Civil Engineering,Fujian Agriculture and Forestry University,Fuzhou 350108,Fujian,China)

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]福建农林大学交通与土木工程学院,福建福州350108

出　　处：《交通运输工程学报》2022年第1期93-102,共10页Journal of Traffic and Transportation Engineering

基　　金：国家自然科学基金项目(51878178);福建省自然科学基金项目(2019J01231);福建省土木工程多灾害防治重点实验室开放课题(MPMC-2021001);福建省交通运输科技项目(201905)。

摘　　要：为改善砌体柱的受力性能,提出了采用新型超高性能砂浆(UHPM)的砌体柱(UMC),以烧结砖和混凝土砖为研究对象,分别进行了2组UMC的轴压试验,通过与传统砂浆砌体柱(MC)进行对比,探讨了UMC轴压受力机理与破坏模式,评估了现行规范关于砌体轴压承载力计算公式对UMC的适用性,提出了UMC轴压承载力预测公式。研究结果表明:UMC与MC的受力全过程相似,均经历了裂缝前受力阶段、裂缝开展阶段和破坏阶段;但UMC的初裂荷载远高于MC的初裂荷载,烧结砖与混凝土砖UMC分别为相应MC的2.36倍和2.45倍,且都大于MC的极限荷载;UMC与MC均因砌块破坏而丧失承载力,MC的破坏表现出明显的脆性,裂缝主要发展于砂浆与砌块接触面,而UMC的破坏表现出较好的延性,砌块的压碎程度远大于MC;与MC相比,UMC中砂浆不再是一个薄弱环节,UHPM对砌块的横向变形起约束作用,可显著提高砌体柱的承载力,烧结砖和混凝土砖UMC抗压承载力分别为MC的1.74倍和2.00倍,表明UHPM在砌体结构中的应用具有相当的可行性;采用现行规范中的MC强度计算公式将高估UMC的承载力,提出的UMC强度计算公式同时考虑了砌块的强度与UHPM对砌块约束作用。To improve the mechanical properties of masonry columns,a new masonry column with UHPM(UMC)based on the ultra-high performance mortar(UHPM)was proposed.Axial compression test were carried out on two groups of UMC with fired brick and concrete brick.By comparing with the conventional masonry columns(MC),the stress mechanism and failure mode of UMC were discussed.The applicability of formula for calculating the axial compression bearing capacity of masonry columns in the current specification to UMC was evaluated,and the prediction formula for the axial compression bearing capacity of UMC was proposed.Analysis results show that the whole stress process of UMC and MC is similar,which both experience the stress stage before cracking,cracking development stage and failure stage.The initial cracking load of UMC is much higher than that of MC,where,the values of UMC with fired brick and concrete brick are 2.36 and 2.45 times than those of MC,respectively,and both are greater than the ultimate load of MC.Both the UMC and MC lost their bearing capacity due to the block failure.The failure mode of MC shows obvious brittleness,and the cracks mainly develop at the interface between the mortar and the block.However,the failure of UMC shows good ductility,and the crushing degree of block is much larger than that of MC.Compared with MC,mortar in UMC is no longer a weak part,and the UHPM plays a constraint role on the lateral deformation of the block,which can significantly improve the bearing capacity of the masonry column.The compression bearing capacities of UMC with fired brick and concrete brick are 1.74 and 2.00 times that of MC,respectively,indicating that the application of UHPM in masonry structure is quite feasible.The strength calculation formula for MC in the current specification will overestimate the bearing capacity of UMC.The proposed UMC strength calculation formula for UMC takes into account the strength of block and the constraint effect of UHPM on the block.8 tabs,9 figs,25 refs.

关 键 词：桥梁工程 超高性能砂浆砌体 轴压试验 受力机理 极限承载力 计算方法 

分 类 号：U448.33[建筑科学—桥梁与隧道工程]