CN103194983A - Segmental precast assembly method and segmental precast assembly structure for cantilever arm of large capping beam - Google Patents

Abstract

The invention discloses a segmental prefabrication and assembly method of a cantilever arm of a large-scale cover beam, comprising the following steps: prefabricating the cover beam in sections, including a middle prefabricated section and a cantilever prefabricated section; The prefabricated section is hoisted on the bridge pier, and the prefabricated splicing of the intermediate prefabricated section and the bridge pier is completed through the longitudinal sleeve; the two ends of the intermediate prefabricated section are extended to connect the cantilever prefabricated section; All the hoisting of the prefabricated section of the cantilever arm is described, and then the prestressed tendons are introduced to complete the entire assembly of the large cover beam. The invention also discloses a segmental prefabricated assembly structure of a large-scale cantilever arm, which includes a middle prefabricated section and at least two cantilever prefabricated sections. The segmental prefabrication and assembly method of the cantilever arm of the large-scale cover beam and the assembly structure thereof of the present invention have relatively low requirements on the prefabrication of the cover beam and on-site hoisting construction, and good construction stability, and are very suitable for the construction of large-scale cover beams.

Description

Segmental prefabricated assembly method and assembly structure of cantilever arm of large cap beam

technical field

The invention relates to the technical field of prefabricated cover beam construction, in particular to a segmental prefabricated assembly method and an assembled structure of a cantilever arm of a large-scale cover beam.

Background technique

The construction of the cover beam in the bridge is one of the key points of the bridge construction. The main construction method of the traditional cover beam is the bracket method. The mold is set on the upper part of the pier to pour the concrete, and the mold is removed after the concrete is cured and solidified. This method has the following Disadvantages: 1. Long erection period; 2. Consumption of manpower and materials; 3. In the construction of urban bridges, ground traffic will be restricted; 4. The cost of ground support for sites with poor geological conditions is high; 5. Higher requirements for the site .

Therefore, in order to overcome the shortcomings of the above-mentioned bracket method construction, the rapid construction method of prefabricated cover beams and then on-site hoisting is often used. Specifically, according to the construction requirements, the cover beams are prefabricated first, and then the cover beams are transported to the construction site for overall hoisting. This method is very suitable for the construction of small and medium-sized cover beams, but for the construction of large-scale cover beams (such as more than 400 tons), it is difficult to have a matching spreader for lifting operations on site, and due to the large volume and weight, the construction requirements are relatively high , and there are security risks.

Therefore, those skilled in the art have been devoting themselves to developing a segmental prefabricated assembly method and its assembly structure for large-scale cantilever beams, which have lower requirements on the prefabrication of the cover beam and on-site hoisting construction, and are suitable for the construction of large-scale cover beams.

Contents of the invention

In view of the above deficiencies in the prior art, the present invention proposes a segmental prefabricated assembly method and its assembly structure for large-scale cantilever beams, which have relatively low requirements for the prefabrication of the cover beam and on-site hoisting construction, and are suitable for the construction of large-scale cover beams.

In order to achieve the above object, the present invention provides a segmental prefabricated assembly method for the cantilever arm of a large cap beam, which includes the following steps:

Step 1: Prefabricate the cover girder in sections according to design requirements, the cover girder includes a middle prefabricated section stacked on the pier and at least two cantilever prefabricated sections connected to both ends of the middle prefabricated section, the The middle prefabricated section is provided with a longitudinal casing connected to the pier, and the connecting end faces of the middle prefabricated section and the cantilever prefabricated section are provided with connecting grooves and transverse cross-sections for piercing prestressed tendons. casing;

Step 2: using a crane to hoist the intermediate prefabricated section onto the bridge pier, and complete the prefabricated splicing of the intermediate precast section and the bridge pier through the longitudinal casing;

Step 3: extending and hoisting the cantilever prefabricated section toward both ends of the middle prefabricated section, and connecting and fixing it through the connecting groove;

Step 4: complete all the hoisting of the cantilever prefabricated section, and then pass through the middle prefabricated section and the cantilever prefabricated section transversely through the transverse sleeve to introduce prestressed tendons to complete the entire assembly of the large cover beam.

As a further improvement of the present invention, in the third step, a bridge deck crane is installed on both ends of the intermediate precast section to hoist the cantilever precast sections at both ends.

The above-mentioned technical scheme is especially suitable for the construction of large-scale cover beams. This assembly method utilizes segmental prefabrication of the middle prefabricated section and the prefabricated sections with cantilever arms at both ends. The large-scale cover beam is hoisted and spliced at the construction site of the cover beam, and the longitudinal direction is pre-embedded on the middle prefabricated section. Sleeves and transverse casings, as well as the pre-embedded transverse casings on the prefabricated section of the cantilever, enable them to be prefabricated and spliced on the piers stably, and at the same time overcome the shortcomings of the bracket method and the existing overall hoisting method on site, achieving The purpose of rapid construction, convenient hoisting, and reduction of prefabrication and construction requirements.

The present invention also proposes a segmental prefabricated assembly structure of a large-scale cantilever arm, including a middle prefabricated section and at least two cantilever prefabricated sections, the middle prefabricated section is provided with a longitudinal casing connected to the bridge pier, and the Both the connecting end faces of the middle prefabricated section and the cantilever prefabricated section are provided with connection grooves and transverse casings for passing through prestressed tendons, and the cantilever prefabricated sections are hoisted and fixed on the The prestressed tendons are provided on both ends of the intermediate precast section and between the intermediate precast section and the cantilever precast section.

The segmental prefabricated assembly structure of the cantilever arm of the large-scale cover beam of the present invention has a simple and reliable structure, is especially suitable for the construction of a large-scale cover beam, greatly reduces the difficulty of construction, has good stability in the construction process, and is convenient for on-site construction.

The idea, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings, so as to fully understand the purpose, features and effects of the present invention.

Description of drawings

Fig. 1 is a schematic block diagram of the process flow of the segmental prefabricated assembly method of the cantilever arm of the large-scale cover beam.

Figure 2 is a schematic diagram of the application of the segmental prefabricated assembly structure of the cantilever arm of the large-scale cover beam.

FIG. 3 is a top view of FIG. 2 .

Detailed ways

Embodiment one:

Fig. 1 is a schematic block diagram of the process flow of the segmental prefabricated assembly method of the cantilever arm of the large-scale cover beam. This embodiment proposes a segmental prefabrication and assembly method of a large-scale cover beam cantilever to realize the successful hoisting of a large-scale cover beam exceeding 400 tons on two bridge piers. As shown in Figure 1, this embodiment is prefabrication of a section segment and two matching cantilever prefabricated segments are spliced on-site on the two piers, which specifically includes the following steps:

Step S1: Prefabricate the cover girder in sections according to design requirements, the cover girder includes a middle prefabricated section stacked on the pier and at least two cantilever prefabricated sections connected to both ends of the middle prefabricated section, the The middle prefabricated section is provided with a longitudinal casing connected to the pier, and the connecting end faces of the middle prefabricated section and the cantilever prefabricated section are provided with connecting grooves and transverse cross-sections for piercing prestressed tendons. casing;

Step S2: using a crane to hoist the intermediate prefabricated section onto the bridge pier, and complete the prefabricated splicing of the intermediate precast section and the bridge pier through the longitudinal casing;

Step S3: extend and hang the cantilever prefabricated section toward both ends of the middle prefabricated section, and connect and fix it through the connecting groove;

Step S4: Complete all the hoisting of the cantilever prefabricated section, and then introduce prestressed tendons through the transverse sleeve through the middle prefabricated section and the cantilever prefabricated section to complete the entire assembly of the large-scale cover beam.

As a further specific implementation of this embodiment, in step S3 of this embodiment, a bridge deck crane is installed on both ends of the intermediate precast section to hoist the cantilevered precast section at both ends.

Of course, in other specific embodiments, if the prefabricated section of the cantilever arm is too long, the prefabricated section of the cantilever arm can also be divided into multiple prefabricated sections, and then assembled on site as above.

The assembling method of this embodiment is especially suitable for prefabricated hoisting and assembling of large cap beams. Compared with the bracket method of the prior art, this embodiment requires a shorter construction period and has less impact on ground traffic and the environment; There is an overall prefabricated hoisting method. This embodiment overcomes the problem that the overall hoisted cover girder is too heavy to be hoisted, and the middle prefabricated section of this embodiment is first separately installed on the corresponding pier, which is more convenient to lift and has better installation stability. The middle prefabricated section is fixed to the bridge pier, and then the two ends are connected with grooves to extend and splice the cantilever prefabricated section. The construction is more convenient and fast, and the construction can continue to be extended to both ends according to the design requirements, and the extensibility is good.

Embodiment two:

Figure 2 is a schematic diagram of the application of the segmental prefabricated assembly structure of the cantilever arm of the large-scale cover beam. In this embodiment, a segmental prefabricated assembly structure of a large-scale cantilever cantilever can be built according to the construction steps of the first embodiment, as shown in Figure 2 and Figure 3, the assembled structure includes a middle prefabricated section 1 and two cantilever sections The prefabricated section 2, the middle prefabricated section 1 is provided with a longitudinal sleeve connected to the pier 3 (not shown in the figure), and the connection end faces of the middle prefabricated section 1 and the cantilever prefabricated section 2 are provided with connecting grooves (in the figure not shown) and transverse sleeves (not shown in the figure) for passing through prestressed tendons are arranged throughout, the cantilever prefabricated section 2 is hoisted and fixed on the two ends of the middle prefabricated section 1 through the connecting groove, and The prestressed tendons are provided through between the middle prefabricated section and the cantilever prefabricated section.

Of course, in other specific embodiments, if the prefabricated section of the cantilever arm is too long or too heavy, the prefabricated section of the cantilever arm can also be divided into multi-section prefabricated sections of the cantilever arm, and then assembled to the two ends of the middle prefabricated section.

The structure of this embodiment is simple and reliable, especially suitable for the construction of large cap beams, which greatly reduces the difficulty of construction, has good stability in the construction process, and is convenient for on-site construction.

The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make many modifications and changes according to the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art shall be within the scope of protection defined by the claims.

Claims (3)

1. a large-scale bent cap is chosen arm segmentation precast segment assembling method, it is characterized in that, may further comprise the steps: step 1: according to designing requirement, described bent cap is carried out prefabricate, at least two joints that described bent cap comprises prefabricated section of the centre that is layered on the bridge pier and is connected prefabricated section two ends, described centre are chosen prefabricated section of arm, described centre is provided with the vertical sleeve pipe that is connected with described bridge pier for prefabricated section, prefabricated section of described centre with described choose to be provided with on the end face being connected of prefabricated section of arm connect tongue and groove and run through the horizontal sleeve pipe that is provided be used to wearing presstressed reinforcing steel;

Step 2: adopt loop wheel machine with the prefabricated section lifting in described centre to described bridge pier, finish the precast spliced of prefabricated section of described centre and described bridge pier by described vertical sleeve pipe;

Step 3: the extension of prefabricated section two ends is hung and is connect described prefabricated section of the arm of choosing towards described centre, is connected and fixed by described connection tongue and groove;

Step 4: finish described whole hanging of choosing prefabricated section of arm and connect, laterally run through prefabricated section of described centre and described prefabricated section importing of the arm presstressed reinforcing steel of choosing by described horizontal sleeve pipe again, finish the whole assembly unit of large-scale bent cap.

2. large-scale bent cap as claimed in claim 2 is chosen arm segmentation precast segment assembling method, it is characterized in that: what the both ends that described step 3 is prefabricated section in described centre arranged bridge floor loop wheel machine lifting both ends of the surface chooses prefabricated section of arm.

3. a large-scale bent cap is chosen arm segmentation precast segment splicing structure, it is characterized in that: prefabricated section and at least two is saved and to choose prefabricated section of arm in the middle of comprising, described centre is provided with the vertical sleeve pipe that is connected with bridge pier for prefabricated section, prefabricated section of described centre with described choose to be provided with on the end face being connected of prefabricated section of arm connect tongue and groove and run through the horizontal sleeve pipe that is provided be used to wearing presstressed reinforcing steel, described prefabricated section of the arm of choosing is fixed on the both ends of the surface of prefabricated section of described centre by described connection tongue and groove lifting, and prefabricated section of described centre and described choose to run through between prefabricated section of the arm be provided with described presstressed reinforcing steel.

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