秦沈客运专线预应力混凝土双线整孔简支箱梁制造工艺

Construction Method on Post-tensioned Pre-stressed Concrete Double-track Box Beam of Qinhuangdao-Shenyang Passenger Dedicated Rail Line

秦沈客运专线列车运行速度达 2 0 0km·h- 1 ,为保证列车安全运行及旅客乘坐舒适 ,对桥上轨道的平顺性要求很高 ,桥梁不仅应有足够的强度、刚度以及小的后期徐变变形 ,同时还应具有良好的耐久性 ,并要求实现快速施工 ,因此大量使用了预应力混凝土简支箱梁 ,并主要采用现场预制、架桥机架设的施工方法。预应力混凝土简支箱梁在我国铁路建设中大规模采用尚属首次 ,没有工业化制造的成熟经验。本文通过跨度 2 4m预应力混凝土双线整孔简支箱梁模板设计、混凝土配合比试验、混凝土灌注和振捣工艺、水化热温度、张拉工艺和各项摩阻、预施应力效果、顶梁和移梁、梁体弹性上拱及缩短量、徐变上拱等一系列实用性试验和后期静载试验、长期上拱测试的验证 ,为秦沈客运专线预应力混凝土简支箱梁制造质量提供了保证 。

The maximum speed of Qinhuangdao Shenyang passenger dedicated rail line will reach 200 km·h -1 , the rail on bridge is required to be very straight and steady so as to safely run a train and provide comfort for passengers. A beam as the base of rail must have strong strength, rigidity, small subsequent creep camber, and excellent durability as well as rapid in construction. So post tensioned pre stressed concrete box beams are widely used and precast in situ. Precast box beams are installed by bridge erectors. Precast box beams are widely used in railway bridge construction in China for the first time. So we are lack of experience in doing large scale precasting. With the design of the full scale double track box beam (span: 24 m), the investigation of beam of formwork, mix design of concrete, pouring, vibrating, temperature of heat of hydration, pre stressing method, friction of pre stressing, result of concrete stress, elastic and creep camber, elevating and moving as well as static test result of the beam, we provided the proven experience for large scale pre casting done.