CN108487084A - Prefabricating load for No. 0 block temporary support brackets of bridge applies structure - Google Patents

Abstract

The invention discloses a preload application structure for the temporary support bracket of the No. 0 block of the bridge, which includes a plurality of double-peak reaction frames. A pair of vertical columns arranged at intervals symmetrically in the width direction of the pier body, a plurality of transverse beams arranged horizontally between the vertical columns at intervals, diagonal braces obliquely connecting the columns and the main truss beam, and the preloading structure also includes The prestressed steel bars that vertically penetrate the vertical columns and extend into the pier body, the support cushions set on the temporary support brackets for supporting the double-peak reaction frame, and the support cushions set on the temporary support brackets for A jack for counter-pressing the bimodal reaction frame. The present invention uses the mechanism of the vertical prestressed steel bar and the double-peak reaction frame, and simultaneously uses the jack to apply the preload to the bracket, and efficiently solves the problem of applying the preload to the bracket of No. 0 block under special circumstances.

Description

Preload load application structure for temporary support brackets of No. 0 block of the bridge

technical field

The invention relates to the technical field of bridge construction, in particular to a preload application structure for temporary support brackets of No. 0 block of the bridge.

Background technique

The construction of the bridge superstructure mainly includes prefabricated installation and cast-in-place two categories. According to the style and size of the bridge, the cantilever splicing method belonging to prefabricated installation or the cantilever pouring method belonging to cast-in-place are often used. Among them, the hanging basket method is often used in the construction of the No. 0 block of the bridge, which is also suitable for cantilever splicing and cantilever pouring.

When the hanging basket method is used for cantilever pouring and segmental cantilever assembly, the continuous beam is extended segment by segment according to the T-structure cantilever, and finally closed to form a continuous bridge structure. The section on the top of the pier body mainly serves as the reference section for the extension of the T structure, which is called the No. 0 section or the No. 0 block. Sometimes the No. 0 block does not meet the operating space of the hanging basket, and the reference section includes the No. 0 block and the No. 1 block. cast in place. The reference section is designed as a cast-in-place section of the temporary support structure, which serves as the reference section for the hanging basket assembly platform and the extension of the T structure, and prepares for the construction of subsequent sections. Block 0 of the continuous steel structure is a large-volume concrete cast-in-place construction, and requires one-time casting. The strength and stiffness of the supporting structure are the key to determine whether the cast-in-place beam construction is successful. The bracket is the main force-bearing member that bears the self-weight of newly poured concrete, formwork brackets, small appliances, and the load of construction workers. After the bracket is assembled, structural review and weld inspection are required. In order to ensure that the line shape of the beam section is consistent with the design during the pouring of Block 0 or before the strength of the prestressed concrete bears the load, and to avoid excessive deformation and secondary deformation causing concrete stress cracks, the preloading of the bracket must be carried out. Frame preloading mainly eliminates the inelastic deformation of the bracket, measures the amount of elastic deformation, and sets the pre-throwing height of the box girder bottom form; secondly, checks the stress strength and stiffness of the bracket rods and the overall stability of the bracket. Block 0 is limited by conditions such as the height of the pier, the width of the bridge deck, the river, and the proximity of existing lines. The traditional preloading methods such as physical surcharge and prestressed equivalent loading of the cap cannot be implemented. There is an urgent need for a reliable preloading method. Apply structure.

Contents of the invention

The purpose of the present invention is to provide the preloading load applying structure that is used for bridge No. 0 piece temporary support bracket, can overcome the weak point of prior art, through the mechanism of vertical prestressed steel bar and double-peak reaction force frame, simultaneously The jack is used to apply the preload to the bracket, which efficiently solves the problem of applying the preload on the bracket of the No. 0 block under special circumstances.

Above-mentioned technical purpose of the present invention is achieved through the following technical solutions:

The preload load application structure used for the temporary support bracket of the No. 0 block of the bridge includes a plurality of double-peak reaction frames, and the double-peak reaction frame includes the main truss installed above the temporary support bracket, and the pier body along the bridge pier. A pair of vertical columns symmetrically arranged at intervals in the width direction, a plurality of transverse beams arranged horizontally between the vertical columns at intervals, and diagonal braces obliquely connecting the columns and the main truss girder. The compressive load application structure also includes prestressed steel bars vertically penetrating through the vertical column and extending into the pier pier body, and a support for supporting the double-peak reaction frame arranged on the temporary support bracket. Support cushions, jacks arranged on the temporary support brackets for counter-pressing the double-peak reaction frame.

Through the mechanism of vertical prestressed steel bars and double-peak reaction frames, and at the same time, jacks are used to apply preload to the bracket, which effectively solves the problem of applying preload to the bracket of No. 0 block under special circumstances; the preload The load application structure has a wide range of application space due to its convenient disassembly and installation, strong safety and reliability, good preloading effect, low cost investment, convenient transportation, and high material utilization rate.

Preferably, in the width direction of the bridge, the double-peak reaction frame is provided on the pier body, and the double-peak reaction frame on different pier bodies are coplanar on the same width section; in the length direction of the bridge, The double-peak reaction frames on the same pier body are arranged side by side at intervals.

As a result, the double-peak reaction force frame regularly and continuously covers the entire top of the No. 0 block, satisfying the jacking and preloading operation of the entire area of the No. 0 block.

Preferably, the main truss and the vertical column are welded and consolidated, the transverse beam is welded and consolidated with the vertical column, and the top of the diagonal brace is welded and consolidated with the top of the vertical column obliquely. The knot and the bottom are obliquely welded to the end of the main truss or to the middle of the main truss.

The main components of the double-peak reaction frame are welded and consolidated. The structure is stable, the strength and rigidity are high, and it can withstand a large jacking preload. At the same time, it is easy to process.

Preferably, the preload application structure includes at least three bimodal reaction frames arranged side by side at intervals, each of the bimodal reaction frames is welded with transverse channel steel on the brace.

The cross-link channel steel is welded with the middle part of the diagonal bracing to further increase the structural strength and stability of the double-peak reaction frame, and to increase the uniformity of stress and the ability to withstand the load of each double-peak reaction frame when the jack is applied. Raise the size of the pre-pressure.

Preferably, the preload application structure further includes a small beam fixed on the top of the vertical column, and an anchor set on the small beam for fixing the prestressed steel bar.

Preferably, the support bolster is located between the piers of the pier, and the jack is located directly below the connection between the diagonal brace and the main truss girder.

The setting of the jack enables the bracket to be subjected to balanced back pressure, which can well eliminate the inelastic deformation of the temporary support bracket. The setting of the support cushion can restrain the reaction force formed by the jack while supporting the weight of the double-peak reaction frame, so that the stress between the double-peak reaction frame and the temporary support bracket is in balance. The setting position of the jack prevents extra lateral extrusion and bending force when the jack performs reverse jacking, reduces unnecessary other loads, and ensures that the jacking pressure is not dispersed, and the jacking effect is good.

Preferably, the small beam is welded by two I-beams, and the anchors can be standard anchor nuts.

Preferably, the included angle between the diagonal brace and the main truss in the horizontal direction is 50°.

Preferably, the support cushion is in close contact with the temporary support bracket and the bottom of the double-peak reaction force frame.

Ensure the stability and safety of the overall structure.

In summary, the present invention has the following beneficial effects:

Through the mechanism of vertical prestressed steel bars and double-peak reaction frames, and at the same time, jacks are used to apply preload to the bracket, which effectively solves the problem of applying preload to the bracket of No. 0 block under special circumstances; the preload The load application structure has a wide range of application space due to its convenient disassembly and installation, strong safety and reliability, good preloading effect, low cost investment, convenient transportation, and high material utilization rate.

Description of drawings

Fig. 1 is the structural representation of the present invention in bridge width direction;

Fig. 2 is a schematic diagram of the structure of the embodiment in Fig. 1 in the direction of the length of the bridge.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and preferred solutions.

This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. Those skilled in the art can make modifications to this embodiment without creative contribution as required after reading this specification, but as long as they are within the rights of the present invention All claims are protected by patent law.

Embodiment: As shown in Figure 1-2, the preload application structure used for the temporary support bracket of the No. 0 block of the bridge includes a plurality of double-peak reaction force frames 2, and the double-peak reaction force frame includes a set of temporary support brackets. 100 above the main truss girder 4, a pair of vertical columns 5 symmetrically spaced apart along the width direction of the pier body 200, a plurality of transverse beams 6 horizontally arranged between the vertical columns at intervals, diagonally connecting the columns and the main The diagonal brace 7 of the truss girder, the prestressed load application structure also includes the prestressed steel bar 1 vertically penetrating the vertical column and extending into the pier body, and the double peak reaction frame set on the temporary support bracket Support cushion 8, be located at the jack 3 that is used for carrying out backpressure to double-peak reaction force frame on the temporary support bracket.

The model of prestressed reinforcement is JL32.

The total length of prestressed steel bars is greater than 16m.

The pre-embedded length of prestressed steel bars in the pier body is greater than 7m.

The rated load of the jack is 300t.

In the width direction of the bridge, there are double-peak reaction frames on the piers, and the double-peak reaction frames on different piers are coplanar on the same width section; in the length direction of the bridge, the double-peak reaction frames on the same pier The racks are arranged side by side at intervals.

The main truss is welded and consolidated with the vertical column, the transverse beam is welded and consolidated with the vertical column, the top of the diagonal brace is obliquely welded with the top of the vertical column, and the bottom is connected with the end of the main truss or with the middle of the main truss Bias welded consolidation.

The preload application structure includes three double-peak reaction frames arranged side by side at intervals, and cross-link channel steel 11 is welded on the diagonal bracing of each double-peak reaction frame.

The preload application structure also includes a small crossbeam 9 fixed on the top of the vertical column, and an anchor 10 arranged on the small crossbeam for fixing the prestressed steel bars.

The small beam 9 is coplanar with the core of the vertical column.

The supporting cushions are located between the pier bodies, and the jack is located directly below the connection between the diagonal brace and the main truss girder.

The small beam is welded by two I-beams, and the anchors can be standard anchor nuts.

The angle between the diagonal brace and the main truss beam in the horizontal direction is 50°.

The support cushion is closely attached to the bottom of the temporary support bracket and the double-peak reaction force frame.

Claims (9)

1. The preload application structure used for the temporary support bracket of the No. 0 block of the bridge, which is characterized in that it includes a plurality of double-peak reaction frames (2), and the double-peak reaction frame includes a temporary support bracket ( 100) above the main truss girder (4), a pair of vertical columns (5) arranged at intervals symmetrically along the width direction of the pier body (200), and a plurality of transverse partitions arranged horizontally between the vertical columns at intervals Beams (6), diagonal braces (7) obliquely connecting the column and the main truss girder, and the preload application structure also includes vertically penetrating the vertical column and extending into the pier body The prestressed steel bar (1), the support cushion (8) set on the temporary support bracket for supporting the double-peak reaction frame, the support cushion (8) set on the temporary support bracket for The double-peak counterforce frame is a jack (3) for backpressure. 2. The preload application structure for bridge No. 0 block temporary support bracket according to claim 1, characterized in that: in the width direction of the bridge, the pier pier body is provided with the double peak reaction force frame , the double-peak reaction frames on different pier bodies are coplanar on the same width section; in the length direction of the bridge, the double-peak reaction frames on the same pier body are arranged side by side at intervals. 3. The preload application structure for bridge No. 0 block temporary support bracket according to claim 1, characterized in that: the main truss and the vertical column are welded and consolidated, and the transverse diaphragm It is welded and consolidated with the vertical column, the top of the diagonal brace is obliquely welded and consolidated with the top of the vertical column, and the bottom is obliquely welded with the end of the main truss beam or with the middle of the main truss beam. Knot. 4. The preload application structure for bridge No. 0 block temporary support bracket according to claim 2, characterized in that: the preload application structure at least includes three double-peak reaction frames arranged side by side at intervals , the cross-linked channel steel (11) is welded on the diagonal bracing of each bimodal reaction force frame. 5. The preload application structure for the temporary support bracket of No. 0 block of the bridge according to claim 1, characterized in that: the preload application structure also includes a small wall mounted on the top of the vertical column A crossbeam (9), and an anchor (10) arranged on the small crossbeam for fixing the prestressed steel bars. 6. The preload application structure for bridge No. 0 block temporary support bracket according to claim 1, characterized in that: the support cushion is located between the pier body, the jack is located in the Just below the junction of the diagonal brace and the main truss. 7. The preload application structure for the temporary support bracket of No. 0 block of the bridge according to claim 5, characterized in that: the small beam is welded by two I-beams, and the anchor can be Standard anchor nuts. 8 . The preload application structure for the temporary support bracket of No. 0 block of the bridge according to claim 1 , wherein the angle between the diagonal brace and the main truss in the horizontal direction is 50°. 9. The preload application structure for the temporary support bracket of No. 0 block of the bridge according to claim 1, characterized in that: the support cushion is connected with the temporary support bracket and the double-peak reaction force frame Close fit bottom.