最大钢筋直径控制钢筋混凝土构件的裂缝宽度.doc

  最大钢筋直径控制钢筋混凝土构件的裂缝 宽度# 李龙起，周东华，王鹏** 5 10 （昆明理工大学建筑工程学院，昆明 650093） 摘要：对必威体育精装版修订的《混凝土结构设计规范》（GB50010-2010）裂缝宽度验算公式进行变换， 首先提出用一新的正截面承载力计算中的纵向受拉钢筋配筋率、钢筋应力和钢筋直径的关系 曲线代替常用的按有效受拉混凝土截面面积计算的纵向受拉钢筋配筋率、钢筋应力和钢筋直 径的关系曲线；接着给出了结构设计时应该注意的重要启示和参考图表；最后提出了计算简 便且精度较高的钢筋混凝土受弯构件不需作裂缝宽度验算的最大钢筋直径的统一调整公式。 在设计配筋时只需计算出钢筋应力查表或根据调整公式就可以判定所选钢筋是否满足规范 公式对裂缝宽度限值的要求。 关键词：钢筋混凝土；受弯构件；最大钢筋直径；简化公式；裂缝宽度 中图分类号：TU375.1 15 The largest Diameter of Steel Bar Without Checking Crack Width of Reinforced Concrete Members Li Longqi, Zhou Donghua, Wang Peng (Faculty of EngineeringArchitecture,Kunming University of Science and Technology, 20 25 30 35 40 KunMing 650224) Abstract: Based on the latest revision of Code for Design of Concrete Structures (GB50010-2010),transformation formulae for crack width checking is established. Firstly, curves which are related to ratio of reinforcement for longitudinal tensile steel reinforcement, stress in longitudinal steel reinforcement and diameter of steel bar are substitute for curves which is the function of ratio of steel reinforcement for tensile steel reinforcements calculated according to effective tension sectional area of concrete, stress in longitudinal steel reinforcement and diameter of steel bar.Important messages and tables are also given without checking the crack width of reinforced concrete members. Finally, an accurate simplified expression for the largest diameter of steel bar is proposed. In flexural member’s design, there is no need to check crack width but select largest diameter of steel bars according to the specific tables or approximate expression provided in the text, which shall be met the demand of crack width checking automatically. Keywords: reinforced concrete; flexural members; largest diameter of steel bar; approximate expression; crack width 0 引言 钢筋混凝土结构裂缝控制一直是人们比较重视的问题。特别是随着我国新研制的 [1] 土结构设计规范》（GB50010-2010）按荷载效应的标准组合或准永久组合并考虑长期作用 [3] [2] 最大裂缝宽度验算公式。但是，利用该规范公式进行最大裂缝宽度验算并不会减少工程设计 人员的工作量。尤其是当验算不满足规范规定的最大裂缝