Lateral stiffening construction of concrete cable-stayed bridge box girder

Abstract

The invention relates to a lateral stiffening construction of a concrete cable-stayed bridge box girder. On the basis of the existing construction of the concrete cable-stayed bridge box girder, a lateral stiffening rib vertical to a top plate and a bottom plate is added between two diaphragm plates with inhaul cables; and the lateral stiffening rib can be in an 'I'-shaped mode or an inverse 'T'-shaped construction mode. According to the lateral stiffening construction of a concrete cable-stayed bridge box girder, the space between the diaphragm plates can be properly increased and the segment length of the cable-stayed bridge girder segment is increased on the premise of keeping the stress and deformation of the top plate and the bottom plate of the bridge deck, the requirement of the overall arrangement of the cable-stayed bridge and the requirement of quickening construction periods can be satisfied, the use level of materials is lowered, and the lateral stiffening construction has a simple structure and is convenient to construct.

Description

technical field [0001] The invention relates to a concrete cable-stayed bridge box girder structure in the field of bridge construction engineering, in particular to a concrete cable-stayed bridge box girder transverse stiffening structure. Background technique [0002] At present, there are two methods commonly used in the construction of concrete box girders of cable-stayed bridges in China. (1) A diaphragm perpendicular to the plane of the bridge deck is installed at the anchorage point of the cable-stayed cables along the bridge in the box girder; (2) On the basis of (1), a transverse diaphragm is added in the middle of the two transverse diaphragms. The transverse diaphragm structurally connects the bridge deck, web, and bottom plate, and its main function is to transmit lateral loads as a transverse force member. Provide longitudinal support for the bridge deck and bottom plate, reduce the cross-sectional deformation of the box girder, resist the distortion stress and ...

AI Technical Summary

Problems solved by technology

[0002] At present, there are two methods commonly used in the construction of concrete box girders of cable-stayed bridges in China. (1) A diaphragm perpendicular to the plane of the bridge deck is installed at the anchorage point of the cable-stayed cables along the bridge in the box girder; (2) On the basis of (1), a transverse diaphragm is added in the middle of the two transverse diaphragms. The transverse diaphragm structurally connects the bridge deck, web, and bottom plate, and its main function is to transmit lateral loads as a transverse force member. Provide longitudinal support for the bridge deck and bottom plate, reduce the cross-sectional deformation of the box girder, resist the distortion stress and torsional deformation caused by the torque, and have a cable diaphragm, which can also play the role of transferring the bridge deck load to the stay cables ; For the method (1), there are the following disadvantages: a, because the transverse diaphragm must provide the bridge deck and the bottom plate for longitudinal support, in order to make the bridge deck and the bottom plate structure meet the force requirements, the spacing should not be too large, otherwise the bridge must be greatly increased. The structural size of the panel and the bottom plate, the application of materials is more expensive; b. Since the setting of the transverse diaphragm needs to be in one-to-one correspondence with the stay cables, the setting of the stay cables is restricted by it, and the degree of freedom of segment division of the whole bridge is small, so it is impossible to The construction period of the box girder section is longer if the stay cable distance is relatively large; c. The diaphragm is used as the transverse force member of the box girder, and the bridge deck and bottom plate are used as the lower flange of the beam to participate in the transverse force and there is shear The force hysteresis effect, the shear lag effect is easy to cause local cracks in the concrete box girder structure as a thin-walled member; although the above defects have been improved for the practice (2), the following shortcomings still exist: a. The cable-free diaphragm blocks the passage of the inner formwork of the box girder during construction, which increases the difficulty of construction; b. The material of the cable-free diaphragm is not yet reasonable, and there is room for optimization; due to the existence of the above defects, the Some highway cable-stayed bridge concrete box girder structures have local cracks or excessive material consumption

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