【摘要】 为了建立混凝土结构裂缝验算的统一公式,对28根钢筋混凝土梁进行试验,分析了配筋、保护层厚度和截面高度变化对钢筋重心水平对应的梁侧面的裂缝间距和裂缝宽度的影响规律;确定了结构设计中裂缝宽度验算对应的裂缝形态特征;提出了以纵向受拉钢筋直径和间距为变量的纵向受拉钢筋有效影响区的计算方法;改进了平均裂缝间距及最大裂缝宽度的计算模式,并将计算值与实测值进行了比较。结果表明:建议的公式精度较好,使最大裂缝宽度的计算更为合理,适用于大保护层和高截面的钢筋混凝土梁。更多还原

【Abstract】 In order to establish the uniform formula for checking computations of crack width,the twenty-eight reinforced concrete beams were tested.The effects of the reinforcement,the thickness of concrete cover and the depth of normal section on the crack spacing and crack width at the reinforcement level on the side surface were analyzed.The crack feature corresponded to the checking computations of crack width in design procedure of reinforced concrete structures was determined.The method for calculating the effective influencing area of longitudinal tensile reinforcement was proposed,the diameter and the space of longitudinal tensile reinforcement as variable were considered in the method.The improved calculation mode was proposed for calculating the average crack space and the maximal crack width.Test values and calculated values by formula in code were compared.The results show that the calculated precision of the proposed formula is better.The maximal crack width calculated by the proposed formula is more reasonable.It is suitable for the reinforced concrete beams with large concrete cover or large size section.更多还原