1. A hoisting construction method for a bridge deck of a steel truss bridge under the condition of limited clearance is characterized by comprising the following construction steps:

s1: construction preparation: selecting bridge deck hoisting equipment, limiting height of a steel truss and the hoisting equipment, organizing a bridge girder erection machine to enter a field, prefabricating and transporting the bridge deck;

s2: positioning a bridge girder erection machine: the method comprises the following steps of (1) passing a hole through a bridge girder erection machine, hoisting a crown block into a steel truss, selecting and checking a hanger, and arranging a cross beam sleeper of a support leg in the bridge girder erection machine;

s3: the No. 1 crown block hoisting bridge deck plate moves forward to the portal frame end;

s4: and (3) converting a bridge deck hoisting system: hoisting the No. 2 hoisting point of the bridge deck by using a No. 2 crown block, hoisting the No. 2 hoisting point by using a middle support leg beam sleeper support, moving the No. 1 crown block backwards, and hoisting the No. 1 hoisting point by using a No. 1 crown block;

s5: 2, hoisting bridge deck slab forward and in place by crown block;

s6: beam falling;

s7: hoisting the first span;

s8: transporting the bridge deck to the first span in the truss by using the method;

s9: hoisting the same-hole bridge deck by the crown block 2 piece by piece from the first span;

s10: the bridge girder erection machine moves forwards to pass through the hole;

s11: hoisting the next hole bridge panel;

s12: and sequentially hoisting until the hoisting operation of the final span steel truss bridge deck is finished.

2. The hoisting construction method of the bridge deck of the steel truss bridge under the condition of limited headroom as claimed in claim 1, wherein the bridge deck of the steel truss bridge is influenced by the height of the bridge portal, the first span and the last span utilize the supporting leg beam and the steel truss in the bridge girder erection machine, 1 overhead crane is respectively arranged inside and outside for hoisting, and the hoisting process is as follows: the method comprises the following steps of moving a No. 1 crown block hoisting bridge deck forward to a portal frame end → arranging a support leg beam sleeper in a bridge girder erection machine → dropping a No. 1 hoisting point end of the bridge deck onto the support leg beam sleeper in the bridge girder erection machine → 2 hoisting a No. 2 crown block hoisting bridge deck, loosening a steel wire rope of the No. 1 crown block and moving the steel wire rope backwards to a No. 1 hoisting point of the bridge deck, hoisting the No. 1 crane → longitudinally moving the 2 crown block hoisting bridge deck to a designed bridge deck plate position → dropping a beam → hoisting other bridge decks by the same method.

Background

In the traditional hoisting construction of highway bridge decks, the deck plates are hoisted by adopting a truck crane and a crawler crane, the steel truss bridge is limited by a steel truss bridge portal frame and an upper parallel K-shaped beam, the steel truss bridge is hoisted by adopting the traditional truck crane and crawler crane hoisting mode, the hoisting space is insufficient, the steel truss needs to pass through, the hoisting is carried out in a limited and narrow space, the installed steel truss is easily damaged and has high risk in the hoisting process, and how to effectively and safely hoist the deck plates of the steel truss bridge becomes a severe test.

Disclosure of Invention

In order to overcome the technical problems of insufficient clearance and high hoisting difficulty in the traditional bridge deck slab hoisting by using a truck crane in the prior art, the invention provides a construction method for hoisting a steel truss bridge deck slab under the condition of limited clearance, wherein 1 crown block is respectively arranged inside and outside a steel truss, and a method for effectively converting the hoisting of the steel truss bridge deck slab by using the hoisting of the No. 1 crown block and the combined hoisting of the No. 2 crown blocks is adopted to hoist the steel truss bridge deck slab at the first span and the last span influenced by the height of a bridge portal frame, so that the technical problems are solved.

The invention achieves the aim through the following technical scheme, and provides a hoisting construction method for a steel truss bridge deck under the condition of limited clearance, which comprises the following construction steps:

s1: construction preparation: selecting bridge deck hoisting equipment, limiting height of a steel truss and the hoisting equipment, organizing a bridge girder erection machine to enter a field, prefabricating and transporting the bridge deck;

s2: positioning a bridge girder erection machine: the method comprises the following steps of (1) passing a hole through a bridge girder erection machine, hoisting a crown block into a steel truss, selecting and checking a hanger, and arranging a cross beam sleeper of a support leg in the bridge girder erection machine;

s3: the No. 1 crown block hoisting bridge deck plate moves forward to the portal frame end;

s4: and (3) converting a bridge deck hoisting system: hoisting the No. 2 hoisting point of the bridge deck by using a No. 2 crown block, hoisting the No. 2 hoisting point by using a middle support leg beam sleeper support, moving the No. 1 crown block backwards, and hoisting the No. 1 hoisting point by using a No. 1 crown block;

s5: 2, hoisting bridge deck slab forward and in place by crown block;

s6: beam falling;

s7: hoisting the first span;

s8: transporting the bridge deck to the first span in the truss by using the method;

s9: hoisting the same-hole bridge deck by the crown block 2 piece by piece from the first span;

s10: the bridge girder erection machine moves forwards to pass through the hole;

s11: hoisting the next hole bridge panel;

s12: and sequentially hoisting until the hoisting operation of the final span steel truss bridge deck is finished.

According to the construction method for hoisting the steel truss bridge deck under the condition of limited clearance, the steel truss bridge deck is influenced by the height of the bridge portal, the first span and the last span utilize the support leg cross beam and the steel truss in the bridge girder erection machine, 1 overhead crane is arranged inside and outside the steel truss bridge deck for hoisting, and the hoisting process is as follows: the method comprises the following steps of moving a No. 1 crown block hoisting bridge deck forward to a portal frame end → arranging a support leg beam sleeper in a bridge girder erection machine → dropping a No. 1 hoisting point end of the bridge deck onto the support leg beam sleeper in the bridge girder erection machine → 2 hoisting a No. 2 crown block hoisting bridge deck, loosening a steel wire rope of the No. 1 crown block and moving the steel wire rope backwards to a No. 1 hoisting point of the bridge deck, hoisting the No. 1 crane → longitudinally moving the 2 crown block hoisting bridge deck to a designed bridge deck plate position → dropping a beam → hoisting other bridge decks by the same method.

Generally, compared with the prior art, the technical scheme of the invention can achieve the following beneficial effects:

1. according to the construction method for hoisting the deck slab of the steel truss bridge under the limited clearance condition, the hoisting of the prestressed box girder of the approach bridge is fully considered, the clearance in the steel truss is analyzed, the bridge girder erection machine is innovatively used for hoisting, the clearance of the steel truss is considered in the process of customizing the bridge girder erection machine, the structure of the bridge girder erection machine is optimized, and the height of the bridge girder erection machine is ensured to meet the clearance requirement of the steel truss; meanwhile, a scientific hoisting sequence and method are adopted, 1 crown block is arranged inside and outside the steel truss respectively, and the method of effective conversion of hoisting of the number 1 crown block and combined hoisting of the number 2 crown blocks is adopted, so that the problem that the bridge deck slab of the steel truss with the first span and the last span influenced by the height of the bridge portal is hoisted is solved, and the problem that the clearance is insufficient when the traditional bridge deck slab is hoisted by using a truck crane is solved effectively.

2. According to the method for hoisting the bridge deck of the steel truss bridge, the traditional bridge deck hoisting mode is changed, appropriate hoisting equipment is selected, and the hoisting sequence is scientifically changed, so that the problems of insufficient clearance and high hoisting difficulty in hoisting of the traditional bridge deck by adopting a truck crane are effectively solved, and the method has good reference significance for hoisting the concrete bridge deck of the bridge limited by clearance conditions.

Drawings

The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings, in which:

FIG. 1 is an elevation view of a steel truss bridge portal frame according to the present invention;

fig. 2 to 9 are hoisting flow charts of the hoisting construction method of the steel truss bridge deck under the condition of limited headroom.

Detailed Description

The invention is described in further detail below with reference to the drawings and the detailed description.

A construction method for hoisting a bridge deck of a steel truss bridge under the condition of limited clearance mainly comprises the following steps of:

the method comprises the following steps: the construction preparation method mainly comprises the following construction contents:

(1) comprehensively analyzing the hoisting conditions of the full-bridge box girder and the bridge deck, and determining that the hoisting equipment adopts a bridge girder erection machine;

(2) calculating and analyzing the net height of the steel truss and the height of the bridge girder erection machine, and as shown in fig. 1, obtaining an elevation view of a steel truss bridge portal frame;

(3) organizing a bridge girder erection machine to enter a field for assembly according to the field construction condition;

(4) prefabricating and transporting the bridge deck;

step two: the bridge girder erection machine is in place, and the steps mainly comprise the following construction contents:

(1) after the approach box girder is erected, the bridge erecting machine passes through a hole, and the front support leg falls onto the steel truss beam;

(2) hoisting a No. 2 crown block into the steel truss by adopting a truck crane;

(3) selecting and checking the type of a lifting appliance for lifting the bridge deck;

(4) setting cross beam sleepers of support legs in the bridge girder erection machine;

step three: after the bridge deck is transported to the middle support leg by a gun carriage, a No. 1 crown block is used for hoisting the bridge deck and moving the bridge deck forwards to the portal frame end;

step four: the method for converting the bridge deck hoisting system mainly comprises the following steps:

(1) hoisting the No. 2 hoisting point of the bridge deck by using a No. 2 crown block;

(2) no. 2 lifting point utilizes a middle support leg beam sleeper support;

(3) the No. 1 crown block moves backwards;

(4) hoisting a hoisting point No. 1 by a crown block No. 1;

step five: 2, hoisting bridge deck slab forward and in place by crown block;

step six: beam falling;

step seven: hoisting the first span;

step eight: transporting the bridge deck to the first span in the truss by using the method;

step nine: hoisting the same-hole bridge deck by the crown block 2 piece by piece from the first span;

step ten: the bridge girder erection machine moves forwards to pass through the hole;

step eleven: hoisting the next hole bridge panel;

step twelve: and hoisting the final span steel truss bridge deck by a similar method.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.