微弯弧形钢筋混凝土结构裂缝控制验算方法研究

Study on checking computation of crack control for slightly curved rebar reinforced concrete structure

为了解微弯弧形钢筋对裂缝分布和宽度的影响,对配置微弯弧形钢筋的受弯板和某上闸首结构进行了空间有限元计算,并与配置直钢筋的受弯板和上闸首结构进行对比分析。根据分析结果给出了配置微弯弧形钢筋与直钢筋的受弯板、上闸首结构最大裂缝宽度之间的关系,建议在布置微弯弧形钢筋时应避开应力最大部位。结合受弯板试验结果,提出在进行微弯弧形钢筋结构件裂缝控制验算时,可将微弯弧形钢筋换算成直钢筋,并给出裂缝控制标准。

For studying the effect of slightly curved rebar on concrete crack distribution and width,a bending plate and a upper lock head structure reinforced with slightly curved rebar were analyzed by spatial finite element method,and the results were compared with the same structures reinforced with straight rebar. The relationship of the maximum crack width of the two structure reinforced with slightly curved and straight rebar respectively was obtained. It was suggested that the slightly curved rebar could be arranged at any part except the maximum stress area. According to the test of bending plate,it is presented that the slightly curved rebar should be converted to straight rebar when crack control checking calculation is conducted for structure of slightly curved rebar. And the corresponding crack control standards are also given.