降温作用下开裂混凝土拉弯构件的有效轴向刚度计算方法  

Calculation of Effective Axial Stiffness of Cracked Reinforced Concrete Tension-Flexure Members Under Temperature Reduction

作　　者：陈涛 金辰华 张克 刁志纬 吴畅[1,2] 孟少平 CHEN Tao;JIN Chenhua;ZHANG Ke;DIAO Zhiwei;WU Chang;MENG Shaoping(School of Civil Engineering,Southeast University,Nanjing 211189,China;National Prestressing Engineering Technology Research Center,Nanjing 211189,China;School of Architectural Engineering,Jinling Institute of Science and Technology,Nanjing 211169,China;Jiangsu Xinzhu Tongchuang Civil Engineering Co.,Ltd.,Nanjing 211800,China;Architectural Design and Research Institute Southeast University Co.,Ltd.,Nanjing 210096,China)

机构地区：[1]东南大学土木工程学院,南京211189 [2]国家预应力工程技术研究中心,南京211189 [3]金陵科技学院建筑工程学院,南京211169 [4]江苏新筑同创土木工程有限公司,南京211800 [5]东南大学建筑设计研究院有限公司,南京210096

出　　处：《工业建筑》2023年第6期100-104,74,共6页Industrial Construction

基　　金：江苏省自然科学基金青年项目(BK20200376);中央高校基本科研业务费专项资金资助项目(2242021R10081)。

摘　　要：温度作用对超长混凝土结构的影响非常显著。在正常使用荷载作用下,结构可能已经出现少量弯曲裂缝,而在降温作用下,构件中可能产生的拉力将使混凝土构件进一步开裂,构件的刚度会因此大幅降低。提出了一种简化的弹性分析方法,考虑拉弯构件在温度作用下的刚度折减,通过计算迭代至刚度收敛,得到开裂拉弯构件的有效轴向刚度。分别采用所提出的方法和ANSYS有限元模拟,对单跨超静定梁在正常使用荷载和降温共同作用下的内力进行分析,得到梁在温度作用单调增加时的轴力变化曲线。对比两种分析方法的结果,表明提出的简化方法计算的内力与有限元模拟的结果较为吻合,该简化方法避免了复杂的非线性有限元分析,具有较好的可行性和较高的精度。The effect of temperature on ultra-long concrete structures is very significant.Bending cracks may occur on the structure under service loads,while the tensile stress generated by temperature effect will further crack the structures,and thus the stiffness of the members will be reduced significantly.A simplified elastic analysis method was proposed in the paper,which considered the stiffness reduction of reinforced concrete tension-flexure members under temperature effect,and could obtain the effective axial stiffness of cracked tension-flexure members through simple iterations.The internal force of a single-span statically indeterminate beam under combined service load and temperature reduction was analyzed with the proposed method and finite element program ANSYS respectively to obtain the axial force versus temperature effect curve.The comparison between these two methods indicated that the calculated axial force by proposed method coincided well with finite element modeling results.The proposed simplified method could avoid complicated nonlinear analysis and had reasonable feasibility and accuracy.

关 键 词：超长混凝土结构 温度作用 拉弯构件 刚度折减 ANSYS 

分 类 号：TU37[建筑科学—结构工程]