钢筋混凝土剪扭构件承载力可靠度分析  

RELIABILITY ANALYSIS OF REINFORCED CONCRETE MEMBERS UNDER THE COMBINED ACTION OF SHEAR AND TORSION

作　　者：黄靓[1] 鲁懿虬[1] 徐紫鹏[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《工程力学》2012年第4期185-191,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(50808074);教育部新教师基金项目(200805321044);教育部创新团队(2009)

摘　　要：对GB50010-2002《混凝土结构设计规范》(以下简称"规范")剪扭构件承载力计算公式以及黄靓建议的公式进行了可靠度对比分析。结果表明,对于安全等级为二级的剪扭构件,当发生脆性的剪型破坏时,规范公式的受剪可靠指标和受扭可靠指标均值分别为3.23和3.25,不能满足GB50068-2001《建筑结构可靠度设计统一标准》(以下简称《统一标准》)3.7的要求;当发生延性的扭型破坏时,规范公式的受剪可靠指标和受扭可靠指标分别为4.02和2.88,亦不能满足3.2的可靠指标要求;随着扭剪比的变化,规范公式的可靠指标变化幅度较大,受扭和受剪可靠指标之间相差较大,出现不平衡现象。黄靓建议的公式的可靠指标比规范公式高,对于两种破坏类型,可靠指标都在3.6附近,并克服了规范公式可靠指标不平衡的缺点,但对于剪型破坏亦不满足《统一标准》3.7的可靠指标要求。对此,该文把黄靓等人的直线模型再次缩进,提出钢筋混凝土剪扭构件修正公式并作了可靠度分析,结果表明该文修正公式的可靠指标均值在3.75附近,能满足《统一标准》的要求。Torsion-shear strength reliabilities of the code formula（GB50010-2002） and the formula proposed by Huang Liang are analyzed.The results show that for the second-level security structure,the shear reliability index and the torsional reliability index of the Code formula are 3.23 and 3.25 when a brittle shear-type failure occurs,and 4.02 and 2.88 when a ductile torsion-type failure occurs,which cannot meet the demand of 3.7 and 3.2 in GB 50068-2001.As for the formula by Huang Liang,the reliability indexes are near 3.6 no matter what kind of failure occurs,which is close to the demand of the code,but still not safe when a brittle shear-type failure occurs.The reliability indexes of the Code formula change remarkably with the variation of torsion-shear ratio,and there is a clear difference between the shear and torsional reliability indexes.Whereas,the formula proposed by Huang Liang overcomes this defect.A modified formula is provided and its reliability is analyzed.The results show that the reliability indexes of the modified formula are near 3.75,which can satisfy the demand of GB 50068-2001.

关 键 词：钢筋混凝土 剪扭构件 可靠度 建议公式 修正系数 

分 类 号：TU375[建筑科学—结构工程]