Synthesis algorithm for determining reasonable finished-bridge cable force of cable-stayed bridge

Abstract

The invention discloses a synthesis algorithm for determining the reasonable finished-bridge cable force of a cable-stayed bridge. The synthesis algorithm includes the following steps that the structure size is preliminarily protocolled, the cable force is preliminarily protocolled with the minimum bending energy method with main-beam displacement constraints and adjusted to be even, and the live load stress of the main beam is calculated on the basis of considering the live load effect; according to the coupling relationship between prestressing force and the cable force, reasonable prestressed steel is prepared, and a dead-load feasible region is calculated; the reasonability of the protocolled cable force value is judged in combination with the bending moment value of the main beam; the cable force value of a cable-stayed cable is subjected to fine adjustment with the influence matrix method, and the finished bridge state of the cable-stayed bridge is detected. By means of the synthesis algorithm, the limitation of the single method for determining the reasonable finished-bridge cable force is overcome, and the advantages of multiple calculating methods are synthesized; meanwhile, in the process that the cable-stayed bridge is constructed with the full space support method, it can be guaranteed that before supports are dismantled, the main beam is basically separated from the supports, convenience is brought to adjustment of the displacement deviation value of the main beam and dismantling of the supports in construction monitoring and control, the difficulty of construction operation is reduced, the construction period is shortened, and construction cost is reduced.

Description

technical field [0001] The invention relates to a method for determining the reasonable completed cable force of a cable-stayed bridge. Background technique [0002] Cable-stayed bridge, also known as cable-stayed bridge, is a bridge in which the girder body is directly pulled on the bridge tower by many cable-stayed cables. a structural system. The cable-stayed bridge can be regarded as a multi-span elastically supported continuous beam with cable-stayed cables instead of buttresses, which can reduce the bending moment in the beam body, reduce the height of the building, reduce the weight of the structure, and save materials. Due to the adjustability of the stay cables, the design calculation algorithm of the stay cables is different from that of the general bridge type. The cable-stayed bridge can change the internal force distribution of the structure by adjusting the cable force of the stay cables, so the stress of the stay cable force on the structure and deformation ...

AI Technical Summary

Problems solved by technology

Among them, the cable force optimization of the specified force state needs to achieve a reasonable state through repeated adjustment of the cable force, and it is difficult to implement the specified force state through construction; the unconstrained optimization method of cable force needs to change the structural parameters during the operation process. , the calculated cable force at both ends is not uniform, and the influence of live load is not considered, the obtained cable force of the completed bridge may not meet the requirements of the code when the design checking calculation is carried out; the constraint cable force optimization method must determine a reasonable constraint equation to Concerned about the range of expected values ​​such as internal force and displacement of the section as constraints, this method has relatively high requirements for the constraint equation, and at the same time it takes a long time to find a reasonable bridge cable force

When the influence matrix method directly solves the reasonable bridge cable force, it needs rich experience to determine the bridge target, so it will be very difficult and time-consuming to use the influence matrix method alone, and the obtained cable force value is relatively subject to subjective influence

In the research on the construction methods of cable-stayed bridges, scholars mainly studied the construction of cantilever construction method, and less researched the full-house support method, and after the construction of cable-stayed bridges, the deflection of the main girder is downward. Set the pre-camber, so that when the support is removed, the main beam will continue to move downward. If the main beam can reach the design alignment after the support is removed, the construction level must be very high, and it is difficult to construct on site. Meet the design requirements, and there are certain safety hazards when the bracket is removed

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