大型预应力U型薄壳渡槽施工过程仿真分析

Simulative Analysis of Construction of Large-scale Prestressed U-shape Thin Shell Aqueducts

针对预应力U型薄壳渡槽的施工问题,采用单元“生和死”的技术及“时程”分析的方法进行了仿真计算,得出了预应力U型薄壳渡槽在张拉纵、环向预应力锚索、装配横杆、造槽机移位过跨等受载过程中槽身混凝土的力学行为变化规律.在上述一系列的施工过程中,施加预压应力效果较好,采用造槽机施工对槽身损伤小,为渡槽的设计和施工提供了依据.

A simulative analysis of the construction of prestressed U-shape thin shell aqueducts is conducted with the methods of ＂element birth and death＂ and ＂time-history analysis＂. From the analysis the mechanical variations of the concrete in prestressed U-shape thin shell aqueducts are obtained during a series of construction process including prestressing the longitudinal and circumferential tendons, assembling traversing lever, moving the aqueduct-making machine to cross-over span, etc.. Following conclusions are made： application of pre-compressive stress could result better effects; and using aqueduct-making machines in aqueduct construction may reduce damage to the aqueduct in the above mentioned operations, which are bases for aqueduct design and construction.