钢管混凝土拱桥混凝土灌注阶段的受力仿真分析

以一座308米跨的钢管混凝土拱桥为背景,采用平面杆系整体分析与空间实体局部分析相结合的方法来分析混凝土泵注阶段钢管的受力情况。在施工仿真分析的有限元建模中,引入了“单元生死技术”,使得分析过程简单快捷;在处理施工荷载时,充分考虑了泵送液态混凝土复杂的力学性质,提出了分配液态混凝土自重荷载的新方法,并通过温度荷载等效模拟混凝土的自膨胀效应及水化热效应对结构内力的影响。计算分析结果与施工控制中的实测结果吻合较好。

SIMULATION ANALYSIS FOR MECHANIC BEHAVIOR OF CONCRETE-FILLED STEEL TUBULAR ARCH BRIDGE DURING THE COURSE OF CORE CONCRETE PUMPING

Using a 308-meter span concrete-filled steel tubular arch bridge as an example, the method combining global plane structural member analysis with local 3-D solid analysis was applied to analyze the mechanic behavior of steel tube in the course of core concrete pumping. The technique of “birth and death of element” was brought in the finite element model of construction simulation, which simplified the analysis process. In the process of distributing the deadweight of liquid concrete, a new method was proposed which considered the complex mechanic characteristic of pumping liquid concrete. At the same time, the influence on structure internal forces of self-expansion and concrete hydration was simulated equally using temperature loading. The Finite Element analysis results agreed well with the actual measurements during construction.