配置表层钢筋的混凝土梁裂缝宽度计算方法

Calculation method of crack width in reinforced concrete beams with skin reinforcement

为了研究配置表层钢筋的混凝土梁的开裂性能,对8根配置500M Pa钢筋的矩形混凝土梁进行了受弯性能试验.试验结果表明,在构件的混凝土保护层中配置表层钢筋能使平均裂缝间距减小30%-50%,使短期最大裂缝宽度减小29%-70%.根据试验结果,分析了表层钢筋对混凝土梁平均裂缝间距和平均裂缝宽度的影响规律,并在我国规范GB50010—2002裂缝宽度计算模式的基础上,提出了考虑表层钢筋的短期最大裂缝宽度计算公式.根据所提出公式计算的结果能够较好地与试验结果吻合.

To investigate the cracking behavior of reinforced concrete beam with skin reinforcement,a test of eight rectangular section flexural members reinforced with 500 MPa steel bar was carried out.Test results suggest that the skin reinforcement can reduce average crack spacing by 30% to 50% and short-time maximum crack width by 29% to 70%.The effect of skin reinforcement on average crack spacing and average crack width is analyzed based on the test results.A short-time maximum crack width formula concerning the skin reinforcement is put forward that takes into account the crack width formula adopted in the code GB 50010—2002.The proposed calculation formulas agree with experimental results.