跨海低净空现浇单门刚构组合支架技术研究

Technology Research on Cast-in-place Single Door Rigid Frame Composite Support for Low Headroom Across the Sea

以广东大亚湾荃湾特大桥现浇单门刚构为工程依托,通过比对当前施工中较为常见的少支点支架、满堂式支架、梁柱式支架以及满堂梁柱组合形式支架4种支架法,在适用、安全、工效、投资等多个方面进行对比分析,结合计算、验算资料,研制了型钢-扣件脚手架组合体系支架。在实际应用过程中,该方法解决了全桥位于浅海区域、不正规半日混合潮型、深淤泥层、低净空、梁体无预应力、支架安拆困难、型钢焊缝质量控制等难題。最后,对跨海复杂条件现浇单门刚构支架技术的施工工艺及效果进行分析评价。采用此支架技术施工现浇单门刚构,具有施工工期短、经济、安全等优点,值得推广应用。

In view of the cast-in-situ single-door rigid frame of the Quanwan Bridge in Daya Bay, Guangdong Province, the author made a comparative analysis of four kinds of support methods, namely, fewer fulcrum supports, full-house supports, beam-column supports and full-house beam-column combination supports, in aspects of applicability, safety, efficiency and investment. Based on the calculation and checking data, the scaffold combination support system of section steel to fastener was developed. In the actual application process, the method solved the problems, including the whole bridge locating in the shallow sea area, irregular semi-diurnal mixed tide type, deep silt layer, low headroom, no prestressing beam, difficulty in erecting and disassembling brackets, and quality control of section steel welds. Finally, the construction technology and effect of cast-in-situ single-door rigid frame support technology in complicated marine conditions were introduced in detail. The application of this support technology in the construction of cast-in-situ single-door rigid frame has the advantages of short construction period, economy and safety, and is worth popularizing and applying.