钢筋混凝土弯曲破坏试验柱的截面尺寸效应研究  

Study on the Effect of Section Size on Flexural Failure Test Columns of Reinforced Concrete

作　　者：张国军[1] 梁本亮[1] ZHANG Guojun;LIANG Benliang(College of Civil Engineering,Shanghai Normal University,Shanghai 201418,China)

机构地区：[1]上海师范大学建筑工程学院,上海201418

出　　处：《结构工程师》2021年第4期17-24,共8页Structural Engineers

基　　金：国家自然科学基金项目(51578411)。

摘　　要：为了探讨弯曲破坏框架柱的截面尺寸效应,根据收集的218根钢筋混凝土弯曲破坏试验柱抗震性能的试验结果,首先定量分析和探讨了截面尺寸对钢筋混凝土弯曲破坏试验柱的受弯承载力、屈服、峰值和极限水平承载力、延性、极限位移角、各刚度及塑性转动能力的变化规律,然后在理论分析和在试验结果分析的基础上,推导了考虑截面尺寸效应的钢筋混凝土柱正截面大偏心受压破坏的受弯承载力计算公式。分析表明:轴压比在中高值(0.7~1.0)时,名义屈服剪力和名义极限剪力存在截面尺寸效应;当轴压比大于0.7时,试验柱的试验柱的名义弯矩存在截面尺寸效应;当轴压比在0.7~1.0时,截面尺寸效应对试验柱的延性有降低现象;当轴压比大于1时,截面尺寸效应对试验柱最大刚度与弹性刚度比值和试验柱强化刚度与弹性刚度比值有降低现象;当轴压比大于0.7时,截面尺寸效应对试验柱塑性铰转角有降低现象;轴压比在中高值(0.7~1.0)时,试件的安全储备系数减小,表现出明显的尺寸效应。而矩形截面试验柱当轴压比小于1时,截面尺寸效应对试件安全储备系数有降低现象。最后推导出的钢筋混凝土柱正截面大偏心受压破坏受弯承载力计算规范修正公式符合Bazan尺寸效应理论。In order to investigate the section size effect of flexural failure frame columns,according to the seismic performance test results of 218 reinforced concrete flexural failure test columns collected,the variation laws of section size on flexural bearing capacity,yield,peak and ultimate horizontal bearing capacity,ductility,ultimate displacement angle,stiffness and plastic rotation capacity of reinforced concrete columns are first quantitatively analyzed and discussed.Then,on the basis of theoretical analysis and experimental results,the formula of flexural bearing capacity of reinforced concrete column with large eccentric compression failure considering section size effect is derived.The analysis shows that,at medium to high axial compression ratio(0.7~1.0),the nominal yield shear force and the nominal limit shear force of the test column have section size effect;when the axial compression ratio is greater than 0.7,the nominal bending moment of the test column has section size effect;as the axial compression ratio is 0.7~1.0,the section size effect decreases the ductility of the test column;when the axial compression ratio is greater than 1,the section size effect decreases the ratio of the maximum stiffness to the elastic stiffness of the test column and the ratio of the strengthening stiffness to the elastic stiffness of the test column;and when the axial compression ratio is greater than 0.7,the section size effect decreases the plastic hinge angle of the test column;at medium to high axial compression ratio(0.7~1.0),the safety reserve coefficient of the specimen decreases,showing obvious size effect;when the axial compression ratio of the rectangular section test column is less than 1,the section size effect decreases the safety reserve coefficient of the specimen.Finally,the revised formula for calculating the flexural capacity of reinforced concrete column with large eccentricity compression is in accordance with the Bazan size effect theory.

关 键 词：试验柱 截面尺寸效应 弯曲破坏 名义弯矩 延性 刚度 塑性铰区转动能力 

分 类 号：TU375.3[建筑科学—结构工程]