先简支后连续结构体系施工关键技术

Some Key Techniques in the Construction of Simply Supported and Continuous System

采用虚拟层合有限单元法,对先简支后连续结构体系施工关键技术后连续端部浇注及后连续预应力筋张拉顺序、临时支座最佳拆除顺序及后连续端部浇注方式进行仿真分析。仿真结果表明:当连续跨数N≤5时,合理施工工序为"对称浇注、对称张拉",当N>6时,合理施工工序为"隔端浇注、隔端张拉";当连续跨数N≥5时,宜"隔端拆除"临时支座;施工中应优先采用单联浇注方案。

Virtual laminated element method is applied in this paper to simulate and study three key techniques in the construction of simply supported and continuous system, including concrete pouring and tendon strengthening procedures of continuous ends, optimum demolishment sequences of temporary supports, and concrete pouring types of continuous ends. The following conclusions are drawn, which will be of great referential importance to the construction of bridges of the same type. When N &le 5 (N is the number of continuous spans), the concrete pouring sequence of continuous ends should be in accordance with the principle of symmetrical pouring, symmetrical tensioning. When N > 6, such construction procedure should be in accordance with the principle of interval pouring, interval tensioning. When N ≥ 5, the demolishment of temporary supports should be based on the principle of interval ends. Separate end concrete pouring type should be firstly adopted during construction.