钢管超高强混凝土受弯力学性能试验研究  

Experimental research on flexural mechanical properties of ultrahigh strength concrete filled steel tubes

作　　者：周孝军[1,3] 占玉林 牟廷敏[3] ZHOU Xiaojun;ZHAN Yulin;MOU Tingmin(School of Architecture and Civil Engineering,Xihua University,Chengdu 610039,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Sichuan CFST Bridge Engineering Technology Research Center,Chengdu 610041,China)

机构地区：[1]西华大学建筑与土木工程学院,成都610039 [2]西南交通大学土木学院,成都610031 [3]四川省钢管混凝土桥梁工程技术研究中心,成都610041

出　　处：《建筑结构》2024年第6期32-37,共6页Building Structure

基　　金：教育部春晖计划(191643);四川省教育厅科技项目(15ZA0141)。

摘　　要：以官盛渠江大桥为依托,通过3组共6个受弯试件的模型试验,探讨钢管超高强混凝土(抗压强度f_(cu)=80.3~115.2MPa)的受弯力学性能,研究混凝土强度对钢管超高强混凝土的抗弯承载力、变形特征与失效模式的影响。试验结果表明:钢管超高强混凝土的受弯破坏模式与普通钢管混凝土相同,主要为挠度过大而失效,呈整体弯曲破坏,受压区有局部鼓屈;试件进入屈服阶段后,承载力降低较少,具有很好的弯曲延性性能;管内混凝土主要对钢管提供横向约束,避免钢管过早受弯压陷屈曲;在截面含钢率一定时,管内混凝土强度增长对钢管超高强混凝土受弯构件的受弯破坏模式、承载力与延性性能的影响较小。Based on the project of Guansheng Qujiang Bridge,the flexural mechanical properties of ultrahigh strength concrete filled steel tube(UHSCFST)were discussed through the model test of three groups of six bending specimens,and the cube strength(f_(cu))of the core concrete reached 80.3~115.2MPa.The effects of concrete strength on flexural bearing capacity,deformation characteristics and failure modes of UHSCFST specimens were studied.Test results show that the bending failure modes of UHSCFST specimens are the same as that of ordinary ones,mainly manifested as overall bending failure due to excessive deflection,and local bulging in the compression zone.Furthermore,the bending capacity of the specimens do not decrease,even if they have yielded,and all specimens display outstanding bending ductility.The main function of core concrete is to provide radial restraint for steel tube to avoid premature buckling.When the steel content of the specimen section is constant,the strength increases of core concrete has slight impact on the bending failure mode,bearing capacity and ductility of UHSCFST bending specimen.

关 键 词：钢管混凝土 超高强混凝土 受弯承载力 破坏模式 

分 类 号：TU398.9[建筑科学—结构工程]