节段拼装薄壁箱梁带肋大挑臂结构研究

Research on Ribbed Large-cantilever Structure of Segmental Assembled Thin-walled Box Beams

摘要:

为满足工业化建造的需求，须进一步探讨节段拼装箱梁桥的标准化断面形式。采用理论分析与数值模拟相结合的研究方法，对适应全体外预应力节段梁桥的带肋大悬臂的合理构造进行研究。结果表明，全体外预应力节段拼装箱梁桥是一种适合采用工业化建造的桥梁结构形式，采用带肋大悬臂断面形式，可以降低结构自重；加劲肋高度宜选为1 m，加劲肋厚度可选择为22 cm，采用倒梯形布置，并在加劲肋底部与侧边进行倒圆角处理；带肋大断面的斜腹板宜采用双折线腹板构造，以缓解加劲肋根部腹板局部应力集中问题；形成的带肋大悬臂断面结构，能够很好地满足工业化建造的要求，可为节段梁桥设计提供参考。

Abstract:

To meet the demands of industrialized construction, it is necessary to further explore the standardized cross-sectional forms for segmental assembled box beam bridges. The research method combining theoretical analysis and numerical simulation is used to study the rational structure of large ribbed cantilevers suitable for all-external prestressed segmental beam bridges. The results indicate that all-external prestressed segmental assembled box beam bridge is a structural form of bridge suitable for industrialized construction. By adopting a ribbed large-cantilever cross-section, the structural self-weight can be reduced. The recommended stiffening rib height is 1 m, and the stiffening rib thickness can be selected by 22 cm, which is arranged in an inverted trapezoidal pattern, and the rounded corners are applied to the bottom and sides of the stiffening ribs. For the inclined webs of the ribbed large-section, a double-folded web structure is advisably used to alleviate the local stress concentration of the web at the root of the stiffening ribs. The formed ribbed large-cantilever cross-section structure can effectively meet the requirements of industrialized construction and can serve as a reference for the design of segmental beam bridges.