大跨度连续梁桥的线形控制

京杭大运河特大桥是一座主跨为(93 165 93)m的三跨预应力混凝土变截面连续梁桥,主梁除0号～2号块采用支架现浇外,其余3号～24号块均采用挂篮悬臂浇筑,主梁的线形控制较为关键。结合该桥主梁线形控制的施工实际,介绍了主梁的施工方案、线形控制的目的和要点、线形控制计算分析方法。重点阐述了箱梁实际立模高程值的计算过程和箱梁高程测控的布点和监控方法。

Alignment Control of Large Span Continuous Beam Bridge

The huge bridge of the Grand Beijing-Hangzhou Canal is a 3-span(93 165 93)m prestressed concrete changing section continuous beam bridge. Bracket construction technology is used for casting of concrete from block No.0 to No.2.Other blocks of the girder are casted with cradle cantilever casting technology, therefore alignment control of the girder is the key especially. Combined with the alignment control of the girder construction, the calculation method, aim and points of alignment control are introduced. The calculation of formwork process elevation and the control method of the box beam elevation are described in detail.