波形钢腹板组合箱梁横向内力分析及试验研究

Analysis and Experimental Study of Transverse Internal Force in Composite Box-girder with Corrugated Steel Webs

为研究波形钢腹板PC组合箱梁桥顶板在荷载作用下的横向内力及有效分布宽度问题,运用弹性薄板理论,将组合箱梁分解为箱形框架和翼缘板两大部分分别进行分析:将前者展直为四跨连续薄板,将后者简化为一边简支和三边固支的薄板,结合波形钢腹板箱梁,特别是波形钢腹板的受力特点,推导了箱形框架和悬臂翼缘板两部分的内力计算公式,获得这两部分的横向内力结果,利用叠加法得到箱梁顶板的最终横向内力结果。为验证理论的正确性,制作了1根试验梁,进行了3种不同工况下的加载试验,获得了顶板横向应力结果。利用空间有限元法对组合箱梁在局部轮载作用下的受力过程进行了数值仿真分析,采用现行桥梁设计规范有关规定对组合箱梁的有效分布宽度进行对比分析。研究结果表明:箱梁顶板横向应力理论值、试验值、数值结果三者吻合良好,证明了所提出的理论分析方法具有较高的精度;有效分布宽度分析结果表明该方法计算结果偏于安全。

In order to analyze the transverse internal force and the effective distribution width of the top plate in PC composite box-girder bridge with corrugated steel webs under the effect of load,the box girder was divided into two parts,the box frame structure and the flange plate,analyses of which were made respectively by adopting the elastic thin plate theory.The former was straightened as continuous thin plate with four spans,the latter was simplified as a thin plate with one side simply supported and three other sides fixedly supported.By taking the loading properties of the box girder with corrugated steel webs into account,internal force calculation formulas of the two parts were derived,transverse internal force results were obtained and the final transverse internal result of top plate in box girder was obtained by utilizing the superposition principle.Model tests under three different loading conditions were conducted toverify the proposed method,and transverse prestress of top plate was obtained.The numerical analysis was also made on box girder＇s loading process by using spatial finite element analysis,and the effective distribution width of composite box girder was compared by adopting the relevant regulations specified in the Chinese current bridge design specification.The results show that the experiment results,theoretical results and the numerical analysis results of transverse force in top plate of box girder agree very well,which indicates the proposed theoretical method in this paper is of better precision.Effective distribution width analysis results indicate the calculation result is relatively safe.