钢管混凝土拱桥新规范中的设计新理念

最新发布的《公路钢管混凝土拱桥设计规范》(JTG/T D65-06-2015)以及《钢管混凝土拱桥技术规范》(GB50923—2013)传达出一些钢管混凝土拱桥的设计新理念,主要包括:(1)钢管混凝土拱桥的钢管应优先采用直缝焊接管;(2)钢管混凝土拱桥的管内混凝土推荐采用自密实补偿收缩混凝土;(3)哑铃形截面钢管混凝土拱腹腔内的混凝土不应计入主拱截面受力;(4)钢管混凝土主拱节段应采用焊接对接接头;(5)钢管混凝土拱桥宜采用以直代曲法形成主拱线形;(6)中、下承式拱桥悬吊桥面系应具有整体强健性且横梁间必须设置加劲纵梁形成连续结构体系。

New Design Concepts in the New Code of Concrete-filled Steel Tube Arch Bridge

The latest release of Specifications for Design of Highway Concrete-filled Steel Tubular Arch Bridges(JTG/T D65-06—2015) and Technical Code for Concrete-filled Steel Tube Arch Bridge(GB50923—2013) offers some new concepts in designing concrete-filled steel tube arch bridges,which mainly include:(1) the steel tube of concrete-filled steel tube arch bridge should give priority to the longitudinally-welded pipe;(2) the shrinkage-compensating and self-compacting concrete is recommended for the tube of concrete-filled steel tube arch bridge;(3) the concrete between web plates of concrete-filled steel tube arch bridge with dumbbell section should not be included in the stress of main arch;(4) welding butt joints should be adopted in segments of main arch of concrete-filled steel tube arch bridges;(5) the method of replacing curve by straight line should be employed to form the main arch linear of concrete-filled steel tube arch bridge;(6) suspension bridge deck system of half-through and through arch bridges should have the overall robustness and stiffening girders must be set between beams to form a continuous structure system.