CN112575685A

CN112575685A - Heavy tie bar river-crossing construction device for large-span basket type steel arch bridge

Info

Publication number: CN112575685A
Application number: CN202011422251.0A
Authority: CN
Inventors: 马晓云; 章召; 李世林; 吕兵
Original assignee: Liuzhou Ovm Engineering Co ltd; Shanghai Foundation Engineering Group Co Ltd
Current assignee: Liuzhou Ovm Engineering Co ltd; Shanghai Foundation Engineering Group Co Ltd
Priority date: 2020-12-08
Filing date: 2020-12-08
Publication date: 2021-03-30

Abstract

The invention relates to a heavy tie bar river-crossing construction device for a large-span basket-type steel arch bridge, which comprises an anchoring structure, a tensioning end structure, a tensioning machine tool, longitudinal steel strand stress frameworks and safety channel accessories, wherein a plurality of longitudinal steel strand stress frameworks are additionally arranged in the anchoring end structure from one side arch foot area of a main arch one by one and are pulled into the tensioning end structure additionally arranged in the other side arch foot area of the main arch, after special anchors are arranged at two ends of steel strands of the longitudinal steel strand stress frameworks, tensioning operation is carried out at the tensioning end by using the tensioning machine tool, so that the plurality of steel strands respectively reach an approximately horizontal state after being tensioned, parallel longitudinal stress frameworks with certain widths are formed, and the accessories for the safety channel are laid on the parallel longitudinal stress frameworks to form a channel with the passing function of operating personnel. The construction device is reasonable in structure, safe and reliable in construction process, convenient and fast to construct, short in erection period, high in construction quality and low in construction cost.

Description

Heavy tie bar river-crossing construction device for large-span basket type steel arch bridge

Technical Field

The invention relates to a construction device for an arch-first beam-later arch bridge engineering, in particular to a heavy tie bar river-crossing construction device for a large-span basket-type steel arch bridge, belonging to the field of bridge engineering.

Background

The arch-first beam-second beam type is a common construction method for arch bridge construction, and in the construction of a main arch and a prefabricated beam system of a large-scale arch bridge, partial tie rods need to be pulled and arranged after the main arch is finished and before the beam system is erected so as to realize the stability of a main arch structure. Suspension type cableways and heavy-duty catwalks are the main construction methods for tie bars to cross the river. The suspension type cableway is a tie bar river-crossing common method under the working condition that the space under a small arch bridge or arch is not limited, and has the advantages of convenience and quickness in construction, material consumption conservation and the like. However, for special working conditions that the bridge deck height is low, the navigation requirement under the arch is high and the like, the heavy-load catwalk is a safe and reliable tie-bar river-crossing method. In recent years, heavy-duty catwalks are widely applied to the construction of some important arch bridges.

The main types of more conventional heavy duty catwalks currently in use are: the simple catwalk consists of a large-diameter steel wire rope, an arch end steel anchor frame, a catwalk cross connecting piece and a steel plate net surface, or the large catwalk consists of a large-diameter steel wire rope, a midspan cantilever beam, an arch end steel anchor frame, a sag-adjusting hoisting mechanism, a catwalk cross connecting piece and a steel plate net surface. However, in the actual construction process, the catwalk has the disadvantages of more auxiliary mechanisms, difficulty in laying bridge floors, complexity in large-tonnage steel wire rope tightening mechanisms, large sag change during heavy load and the like.

At present, a large arch bridge is built on a channel at a sea outlet in a coastal plain area, and a construction case of a heavy-load catwalk with tie bars crossing the river exists. However, in the construction process of the catwalk, the defects of large auxiliary work amount and long navigation sealing time exist in the early stage, even if the operation optimization is carried out on site, the adverse effects of long construction period of the catwalk, difficult turnover of main materials, high dismantling cost and the like still exist, and the restriction is formed on the efficient development of the large arch bridge engineering construction.

Disclosure of Invention

The invention provides a heavy tie bar river-crossing construction device for a large-span basket type steel arch bridge, which has the advantages of reasonable structure, safe and reliable construction process, convenience and quickness in construction, shortened erection period, improved construction quality and construction cost saving.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a heavy tie bar of heavy tie bar cross river construction equipment for large-span basket type steel arch bridge, includes anchor structure, stretch-draw end structure, stretch-draw machines, vertical steel strand wires atress skeleton, safety channel annex, and a plurality of vertical steel strand wires atress skeletons are installed additional to the anchor end structure in from main arch one side hunch foot district to draw in the stretch-draw end structure that main arch opposite side hunch foot district installed additional, behind the special ground tackle of steel strand wires both ends installation of vertical steel strand wires atress skeleton, utilize stretch-draw machines to carry out the stretch-draw operation at the stretch-draw end, make a plurality of steel strand wires reach approximate horizontal state respectively after the stretch-draw, form the parallel vertical atress skeleton that has certain width, lay the annex for the safety channel on the parallel vertical atress skeleton, form a passageway that has operation personnel current function concurrently.

Furthermore, a plurality of span joists are additionally arranged below the parallel longitudinal stress framework, so that a channel is supported in a segmented mode, and the span sag is reduced.

Furthermore, the sag of the steel strand in the span after being tensioned is less than or equal to 200 mm.

Further, the steel strand is a high-strength low-relaxation steel strand with the diameter of 15.2 mm.

The invention has the beneficial effects that: the steel strand wires hang down heavily loaded type catwalk for a short time is rational in infrastructure, and the main material is cheap, and the construction is convenient, and the ann is torn open to become the cost low. The catwalk has few connecting pieces with the main bridge structure, and only simple two-end anchoring structural parts need to be additionally arranged in the two arch springing areas, so that the structural influence on the main bridge can be ignored. When erecting the catwalk, the requirements for navigation sealing are low, and the construction period is short. Through the construction practice of a plurality of large-scale channel-crossing arch bridges, the good effects of good safety, no influence on channel passage, construction period saving and remarkable reduction of comprehensive cost are shown.

Drawings

Fig. 1 is a structural schematic diagram of a heavy tie bar river-crossing construction device of a span basket type steel arch bridge.

Detailed Description

Embodiments of the present invention are further illustrated below with reference to specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

As shown in figure 1, the heavy tie bar river-crossing construction device (minor-sag heavy-load catwalk structure device) for the large-span basket-type steel arch bridge comprises a plurality of longitudinal steel strand stress frameworks 4, an anchoring end structure 1 additionally arranged from one side arch foot area of a main arch and a tensioning end structure 2 additionally arranged from the other side arch foot area of the main arch are pulled one by one through other auxiliary equipment, and a plurality of inter-span support beams 5 can be additionally arranged in a span according to actual engineering requirements to support a catwalk in a segmented mode so as to reduce the sag of the span. After special anchorage devices are installed at two ends of the steel strand of the longitudinal steel strand stress framework 4, tensioning operation is carried out at a tensioning end by using the tensioning machine 3, the steel strand can reach an approximately horizontal state after being tensioned to 100KN, the sag is small, and the span is only about 200 mm. After a plurality of steel strands are tensioned, a parallel longitudinal stressed framework with a certain width can be formed, on the framework, accessories 6 for a safety channel are sequentially laid from two ends of a main arch to the center, and after midspan butt joint, a small-sag tie-bar river-crossing heavy-load catwalk with the function of passing operators is finally formed.

The anchoring end structure 1 and the tensioning end structure 2 are connected with the arch foot area of the main arch structure in a welding mode. The anchoring end structure 1 and the tensioning end structure 2 are both welded on the steel structure in the arch springing area by the same deformed steel fillet as a holding frame, and then different anchorage devices are used for distinguishing. The anchoring end structure 1 is an extrusion anchorage device and has the advantages of safety and maintenance-free, and the tensioning end structure 2 is a clamping piece anchor and has the advantages of being capable of flexibly adjusting the tension of the steel strand and stably keeping the tension of the steel strand.

The steel strand and anchorage are mature products in the prestress engineering industry and have wide application in various bridge structures. The designer, the supervisor, the general packet and the operation layer can effectively supervise and safely implement the items of the materials.

When single steel strand in the longitudinal steel strand stress framework 4 is tensioned, the tensioning machine 3 is used. 3 small, the weight is only 15Kg, and one person can operate, but can apply the pulling force up to 240KN to single 15.2 mm's steel strand wires, and the construction is very convenient.

The heavy tie bar river-crossing construction device (a small-sag heavy-load catwalk structure device) of the large-span basket type steel arch bridge fully utilizes the advantages of high tensile strength (1860MPa), light dead weight (1.1Kg/m), convenience for tensioning, anchoring and the like of the material of the steel strand, and realizes river-crossing operation of the ultra-thick and ultra-heavy tie bars for the large arch bridge with arch first and beam second in a safe, convenient, efficient and low-cost manner.

Claims

1. The utility model provides a be used for heavy tie rod of large-span basket formula steel arch bridge to cross river construction equipment, includes anchor structure, stretch-draw end structure, stretch-draw machines, vertical steel strand wires atress skeleton, escape way annex, its characterized in that: a plurality of vertical steel strand wires atress skeletons are by one and are installed additional to the anchor end structure in the arch foot district from main arch one side to draw in the main arch opposite side arch foot district install additional stretch-draw end structure, after the special ground tackle of steel strand wires both ends installation of vertical steel strand wires atress skeleton, utilize stretch-draw machines to carry out the stretch-draw operation at the stretch-draw end, reach approximate horizontality respectively after making many steel strand wires stretch-draw, be formed with the vertical atress skeleton of parallel of certain width, lay the annex for the safe passageway on the vertical atress skeleton of parallel, form one and have the passageway of the current function of operation personnel concurrently.

2. The heavy tie-bar river-crossing construction device for the large-span basket-type steel arch bridge according to claim 1, wherein: and a plurality of span joists are additionally arranged below the parallel longitudinal stressed frameworks to play a role in supporting the channel in a segmented manner so as to reduce the sag of the span.

3. The heavy tie-bar river-crossing construction device for the large-span basket-type steel arch bridge according to claim 1, wherein: the sag of the steel strand in the span after being tensioned is less than or equal to 200 mm.

4. The heavy tie-bar river-crossing construction device for the large-span basket-type steel arch bridge according to claim 1, wherein: the steel strand is a high-strength low-relaxation steel strand with the diameter of 15.2 mm.