高强钢筋混凝土梁最大裂缝宽度试验与分析

Research on the maximum crack-width of concrete beam reinforced with high-strength bars

与HRB400级钢筋相比,使用HRB600MPa级高强钢筋能够减少建筑的钢筋用量。600MPa级高强钢筋在推广应用过程中,最受关注的问题是构件的裂缝宽度控制问题。根据16根梁的试验结果,分析了600MPa级高强钢筋混凝土梁的最大裂缝宽度理论计算值与实测值之间的关系。根据试验数据可知,配置600MPa级高强钢筋的混凝土梁裂缝前期发展比配置HRB400级的快,其最大裂缝宽度理论计算值与实测值存在一定的线性关系;理论计算值与实测值的差值与混凝土强度等级和钢筋直径有关;大直径(≥22mm) HRB600级高强钢筋与C30混凝土搭配使用时,无法充分发挥HRB600级高强钢筋的经济优越性。

Compared with the use of HRB400 steel bars,it can reduce the consumption of steel reinforcement when the600 MPa high-strength bars was used in the construction. The most attended problem is the control of the crack width in the process of promoting the use of 600 MPa high-strength bars. Bases on the flexural tests of 16 reinforced concrete beams,the relation between the theoretical value and measured value of crack width for the beams with 600 MPa highstrength steel bars was analyzed. The results indicate that the crack width of the beams with 600 MPa high-strength bars develops faster than the beams with HRB400 steel bars;the theoretical value has been linear with the measured value;the difference between the theoretical value and measured value of the beams is connected with the grade of concrete and the diameter of the bars;it cannot give full play to economic advantage of 600 MPa high-strength bars when the concrete grade is C30 and the diameter of the bars is over 22 mm.