大跨度梁拱协作体系渡槽设计与研究

Design and Research on Large-Span Beam Arch Collaboration System Aqueduct

阐述了大跨度梁拱协作体系渡槽设计计算的基本原理,结合南水北调中线工程李村北干渠渡槽工程介绍了梁拱协作体系渡槽设计的理论、计算方法。梁拱协作体系渡槽采用整体式输水槽身,具有巨大的纵向抗弯刚度,其利用连续槽身的刚度来减小和改善拱肋的受力,使拱截面尺寸得以减小,同时,为使拱槽刚度协调,槽身采用较小的高宽比及薄壁结构,减少了整个渡槽的工程量;梁拱协作体系渡槽利用拱肋平面外设置弧度,提供非保向力,拱圈及立柱成三维空间线型,有效解决了大跨度、小矢跨比渡槽的结构整体稳定问题;梁拱协作体系渡槽的自平衡体系对地基的广泛适应性,解决了地质较差地区修建大跨度拱式渡槽的难题,亦具有明显的经济效益。

This paper introduced the basic principles of design and calculation of the large-span beam arch collaboration system aqueduct,then taking Licun aqueduct of north main canal in the Middle Route of South to North Water Transfer Project as an example,discussed the corresponding design theory and calculation method of beam arch collaboration system aqueduct.Integrated water aqueduct body reduces or improves the stress of arch rib with great longitudinal bending stiffness of continuous aqueduct body in order to minimize the arch section size;at the same time,aqueduct body adopts the small height-width ratio and thin-walled structure to make the arch aqueduct stiffness coordinated and cut down the whole aqueduct engineering quantity.The aqueduct sets arch out of arch rib plane to provide non-directional force,and the arch and the column constitute a three-dimensional space type,which provides an effective solution to overall stability of aqueduct structure with the large span and small rise-span ratio.Equilibrium system of the aqueduct has extensive adaptability to the foundation,which solves construction problem of large span arch aqueduct in the poor bearing capacity geological area,and has obvious economic benefit.