Abstract: System transformation exists in construction of continuous erection by many of simply supported beams．In the construction stage，structural internal force varies according to various orders of construction．A 5一span 30一mile length box—girder bridge is taken as an exam ple and 15 diferent kinds oforders ofconstruction are carried out to analyze．It is shown that the sequence ofcasting monolithic deck first then casting wet joint or the sequence of casting monolithic deck and wet joint alternately is much better to structure．What more，the internal force can be influenced by tension sequence oftendons at beam end．

Key words: continuous erection by many of simply supported beams, order of construction, internal force analysis, tension sequence

摘要： 简支转连续梁桥在施工阶段存在体系转换，不同的施工程序会对结构内力产生影响．通过5跨30m箱梁的具体工程实例，针对15种不同的施工程序进行计算分析．分析表明：先浇筑整体化层后浇筑湿接缝或整体化层与湿接缝交替浇筑对结构受力更有利；梁端湿接缝的预应力张拉顺序在施工阶段也会对结构内力产生一定的影响．

关键词: 简支转连续, 施工程序, 内力分析, 张拉顺序