论文部分内容阅读
根据现行规范的裂缝宽度的计算公式,自编程序计算有黏结和无黏结部分预应力混凝土结构对应于特征裂缝宽度的名义拉应力值,并考虑了截面高度、保护层厚度、混凝土强度等级、非预应力筋配筋率、非预应力筋直径和预应力度等参数对一定裂缝宽度下名义拉应力值的影响,归纳各参数对名义拉应力值的影响系数。对于各参数对名义拉应力值的综合影响系数,可以将各影响系数相乘得到。最后以实际工程为例,比较了用本方法进行裂缝控制和用规范公式计算结果的差异。算例分析表明,基于名义拉应力法的预应力混凝土结构的裂缝控制方法是一种简便、可靠的裂缝控制方法。
According to the calculation formula of the crack width in the current code, the nominal tensile stress corresponding to the characteristic crack width of the prestressed concrete with or without bond is calculated by self-programming, and the cross-sectional height, protective layer thickness, concrete strength grade, The influence of parameters of prestressing tendon reinforcement ratio, non prestressing tendon diameter and prestressing force on nominal tensile stress under a certain crack width, and the influence coefficient of each parameter on nominal tensile stress value is summarized. The comprehensive influence coefficient of the nominal tensile stress value of each parameter can be obtained by multiplying each influence coefficient. Finally, taking the actual project as an example, the differences between the method of crack control and the calculation of the results by the standard formula are compared. The case study shows that the crack control method of prestressed concrete structures based on the nominal tensile stress method is a simple and reliable method for crack control.