Youli Steel Truss-Concrete Composite Continuous Rigid Frame Bridge

Abstract

The invention discloses an optimal force type steel truss-concrete combination continuous rigid frame bridge. The optimal force type steel truss-concrete combination continuous rigid frame bridge comprises a steel-concrete combination bridge beam and tensioned main chord members; the tensioned main chord members and the steel-concrete combination bridge beam form a main truss structure; the tensioned main chord members are fixedly connected to tower columns, are gradually lowered from the tower columns in the longitudinal direction and extend to the lower portion of the steel-concrete combination bridge beam at the connection position of positive and negative bending moments of the main truss structure. The tensioned main chord members are connected with the pressed steel-concrete combination bridge beam through web members to form an optimal force type truss structure system; the main steel chord members are in a tensioned state all the time, and the steel-concrete combination bridge beam with concrete as the main material is in a pressed state all the time; the intensity advantages of steel and concrete are fully performed, the hidden danger of tensile cracking of the concrete is eradicated, the material and measure expenses for applying prestress on the concrete are saved, the construction process is greatly simplified, the work efficiency is improved, and the long-term structural performance of the bridge is stable and reliable. In addition, the dead load of a main beam structure is reduced significantly, and development to extra-long-span continuous rigid frame bridges is facilitated.

Description

technical field [0001] The invention belongs to the field of bridge engineering, in particular to a Youli type steel truss-concrete combined continuous rigid frame bridge. Background technique [0002] Steel truss-concrete combined continuous rigid frame bridge is a relatively new type of rigid frame bridge. It adopts a combined structure of steel truss and concrete, and distributes the force according to the characteristics of steel truss and concrete and the characteristics of the bridge's bending moment. Concrete bears internal forces according to their respective material properties; in the prior art, the lower structure of the bridge has the same structure as the ordinary concrete continuous rigid frame bridge, and the upper structure is a steel-concrete structure composed of steel truss beams and concrete bridge slabs. Combined structure, and appropriate amount of prestressing should be applied by stages in a timely manner to give full play to the material advantages o...

AI Technical Summary

Problems solved by technology

However, the mid-span section of the main girder is located in the lower chord concrete bridge slab and still has the problem of tension cracking. Post-tensioned prestressed beams must be installed in the bridge slab to overcome the problem of tension cracking, which increases the complexity of the structure and The difficulty of construction; in addition, the height of the building above the bridge slab is large, which also limits its scope of use to a certain extent

[0004] To sum up, in the existing steel truss-concrete composite continuous rigid frame bridges, whether it is a top-down bridge or a top-down bridge, there is inevitably a certain section of the concrete bridge slab under tension. Complicated engineering measures must be taken to solve this problem, which not only increases the project cost, but also leaves hidden dangers of bridge structure cracking later, and fails to reflect the composite structure in the whole bridge to give full play to the material advantages of both steel and concrete

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