【摘要】 研究目的:就正交异性铁路桥面板防水层施工,传统工艺采用环氧沥青混凝土方案,但该方案具有施工难度大、费用成本高、使用耐久性低等缺点。为此,本文以沪通长江大桥超高性能混凝土施工为工程背景,研究其施工工艺难点,从而为今后类似工程提供指导作用。研究结论:(1)采用超高性能混凝土进行铁路桥面防水层施工,可起到很好的防水、耐磨作用,同时增加了正交异性桥面板的整体强度;(2)采用专业化搅拌设备可确保超高性能混凝土均匀性,防止钢纤维结团;(3)超高性能混凝土终凝后进行高温蒸汽养护,可大大减少混凝土后期收缩裂纹;(4)提高超高性能混凝土泵送压力,能解决低水胶比、高黏度与泵送距离的矛盾;(5)本研究成果可为今后超高性能混凝土施工提供经验,为超高性能混凝土在公铁两用大桥上推广起到示范作用。更多还原

【Abstract】 Research purposes: In the construction of waterproofing layer of orthotropic railway bridge deck,epoxy asphalt concrete is adopted in traditional technology. This scheme has some shortcomings,such as difficult construction,high cost and low durability. For this reason,this paper takes the construction of ultra-high performance concrete of Shanghai-Nantong Yangtze River Bridge as engineering background,and studies the difficulties of construction technology,to provide guidance for similar projects in the future.Research conclusions:( 1) Using ultra-high performance concrete to construct waterproofing layer on railway bridge surface can play a good role in waterproofing and wear resistance,and increase the overall strength of orthotropic bridge deck.( 2) Using specialized mixing equipment can ensure the uniformity of ultra-high performance concrete and prevent steel fiber agglomeration.( 3) The high temperature steam curing of ultra-high performance concrete after final setting can greatly reduce concrete shrinkage cracks in the later stage.( 4) Increasing pumping pressure of ultra-high performance concrete can solve the contradiction between low water-binder ratio,high viscosity and pumping distance.( 5) The research results can provide experience for ultra-high performance concrete construction in the future,and play a role in demonstrating the promotion of ultra-high performance concrete on highway and railway dual-purpose bridges.更多还原