XT300桁架梁在现浇结构施工临时支架中的应用

Application of XT300 Truss Beam to Falsework for Cast-in-Situ Structure Construction

采用一跨式钢管立柱+贝雷梁临时支架现浇铁路双线32 m简支箱梁时,贝雷梁需采用双层加强型布置方可满足施工要求。这一传统施工工法操作繁琐,且受贝雷片销轴与销孔间错孔扰度影响,支架实际扰度往往与理论计算存在一定差距,导致支架变形控制难度大。新型XT300桁架梁由标准桁架、高抗剪桁架、支撑架、销轴等组成,通过与双层加强型贝雷梁支架方案相比,XT300桁架梁力学特性较双层加强型贝雷梁有较大提高。以铁路双线32 m简支箱梁采用钢管立柱+XT300桁架梁临时支架现浇施工为例,XT300桁架梁支架的内力、应力及扰度均满足要求,减少了支架材料用钢量,简化了支架安装拆卸流程,可作为双层加强型贝雷梁支架的替代方案并适用于更大跨径的临时支架。

When the one-span steel tube post plus bailey beam falsework is used for cast-in-situ construction of32 m simply-supported box girders of double railway tracks,bailey beams need to be arranged in a double-layer reinforced type to meet the construction requirements.This traditional construction method requires complicated operation.In addition,affected by the deflection of misalignment between the pin shaft and the pin hole of the Bailey sheet,the actual deflection of the falsework deviates from the theoretical calculation,resulting in difficulties in the control of falsework deformation.The new XT300 truss beam consists of standard truss,high shear truss,support frame,pin shaft,etc.,and its mechanical behavior is much better than the double-layer reinforced Bailey beam.For example,when the steel tube post+XT300 truss beam falsework is used for cast-in-situ construction of 32 m simply-supported box girders of double railway tracks,the internal force,stress and deflection of XT300 truss beam falsework all meet the requirements,reducing the steel consumption and simplifying the erection and removal of the falsework.Therefore,it is an alternative to double-layer reinforced Bailey beam falsework and can be used for larger spans.