Active jacking auxiliary supporting construction system for lower chord arch support of beam-arch combined rigid frame

Abstract

The invention belongs to the technical field of lower chord arch auxiliary construction of large-span beam arch combined prestressed concrete continuous rigid frame bridges, and discloses an active jacking auxiliary supporting construction system for a lower chord arch support of beam-arch combined rigid frame, which comprises a bottom support system, a supporting system and a pushing system. Thebottom support system comprises a structure for connecting the root of the lower chord arch with the pier and a triangular bracket structure for providing bottom support for the steel pipe column nearthe 1 # section; the supporting system comprises a steel pipe stand column, lateral and transverse supports for preventing the steel pipe column from losing stability, and a distribution beam locatedat the first section of the top of the steel pipe stand column; and the pushing system comprises a jack active jacking device arranged at the bottom of the steel pipe column and a connecting structure of the jack and the triangular bracket. According to the system, cantilever construction of the non-inhaul-cable area of the lower chord arch of the beam-arch combined rigid frame bridge is achieved, and the problems that the upper edge stress of the root of a cantilever is large, and the safety risk is high are solved; the stress state of the root of the inhaul-cable-free construction cantilever between the lower chord arch sections is improved, and the construction safety is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of auxiliary construction of the lower chord arch of a long-span beam-arch combined type prestressed concrete continuous rigid frame bridge, and in particular relates to an active jacking auxiliary support construction system for the lower chord arch bracket of the beam-arch combined rigid frame. Background technique [0002] At present, the beam-arch combined concrete continuous rigid frame bridge is a new type of conventional continuous rigid frame bridge. Due to the mid-span cracking and downward deflection of long-span rigid-frame bridges in recent years, the beam-arch composite rigid-frame bridge is an optimized solution, which improves the unreasonable stress state of steel-frame bridges, thereby improving the spanning capacity of the bridge. [0003] Since the beam-arch combined concrete continuous rigid frame bridge is under the cantilever construction of the 0# and 1# sections of the lower chord arc...

AI Technical Summary

Problems solved by technology

In the prior art, due to the influence of high piers, the lower chord arch section of the arch-beam composite bridge cannot be constructed with floor supports, and the upper and lower chord box girders cannot independently bear the construction load of the long cantilever hanging basket during the construction process, and corresponding temporary assistance is required The construction device completed the pouring construction

At the same time, after the construction of the 1# section of the lower chord is completed, the cantilever section is relatively rigid, and the temporary cable is also used, which will cause a large adverse stress on the top plate attachment of the box girder cable, which is extremely risky, but for the 1# section No auxiliary measures will be applied after the section construction is completed, the constant weight of the 2# section concrete and the weight of the newly added hanging basket will all be borne by the cantilever structure of the lower string, and the root of the cantilever will generate large adverse stress

[0004] Through the above analysis, the existing problems and defects of the existing technology are: when the beam-arch combined concrete continuous rigid frame bridge is under the cantilever construction of the 0# and 1# sections of the lower chord arch, the two sections are in the area without cables, and the chord is lowered at the same time. The root of the arch cantilever is under the multiple loads imposed by the removal of the bracket, the hanging basket installed in the construction section 2#, and the 2# section without cables, the stress on the upper edge of the cantilever root is too large, and the safety reserve is low

[0005] The difficulties in solving the above problems and defects are as follows: Propose the specific structure of the easy-to-remove device suitable for the construction of the cantilever root of the chord arch under the beam-arch composite structure of high piers; explore a new device suitable for improving the stress of the cantilever root of the chord arch under the beam-arch composite structure; Problems of cantilever construction in composite structures without cables

Images