体内预应力波形钢腹板组合梁预应力导入效率研究

摘要

The prestress introduction characteristics of new type steel-concrete composite beam with corrugated web and internal prestress was investigated in this work.A new type of steel encased concrete member was developed to introduce the prestress into the lower flange of the steel-concrete composite beam,and due to the corrugated web,the prestress could be introduced to the lower and upper flange more efficiently.Compared with the conventional composite beam with corrugated web,the mechanical behavior of the new structure can be greatly improved and the weight of beam can be remarkably reduced,so that the frequent replacement of extra-tendons can be avoided.Based on the theorem of Castigliano and thecoordination characteristics of cross-sectional stiffness of composite beam with corrugated steel webs,the method of calculating the efficiency of prestress introduction into composite beam with corrugated web was derived in this work.By comparing the theoretical calculation results with the finite element results,the coefficients of prestress introduction efficiency of composite beam with corrugated web had the consistent variations,validating the rationality of the calculation method proposed in this study.%研究一种新型的体内预应力波形钢腹板组合梁的预应力导入特性.通过设置一种钢包混凝土构件,在波形钢腹板组合梁下翼缘引入体内预应力,设置的波形钢腹板使预应力更大限度地导入上、下翼缘,形成一种新型体内预应力波形钢腹板组合梁.提出的新结构与现有的波形钢腹板组合结构对比,受力性能大幅改善,梁体重量显著降低,避免了体外索的频繁更换.基于卡氏定理,根据波形钢腹板组合梁截面刚度协调特性,推导波形钢腹板的预应力导入效率计算方法,并针对提出的新型体内预应力波形钢腹板组合结构开展预应力导入效率数值分析,通过理论计算结果与有限元对比,发现两种方法获得的导入效率系数变化一致,验证了该文提出的反对称波形钢腹板的预应力导入效率计算方法.