A kind of big segment lifting self-anchored suspension bridge construction method not setting camber
Technical field
The invention belongs to bridge engineering construction technical fields, and in particular to a kind of big segment lifting not setting camber is from anchor
Formula suspension bridge construction method.
Background technology
Currently, self-anchored suspension bridge construction method mainly has " cable after first beam ", " beam-cable-beam " and three kinds of " First cable later girder ",
Wherein, latter two method uses less because needing complicated, expensive construction interim measure." cable after first beam " sets up girder method
It is divided into:Support Method, incremental launching method, big segment lifting method etc..
Support Method is one of " cable after first beam " erection most common method of stiff girder, but since self-anchored suspension bridge is constructed week
Phase is longer, is not suitable for the bridge for having requirement of opening the navigation or air flight under bridge.When span is larger, when riverbed is deeper, rack construction expense is larger, because
This Support Method is not suitable for compared with large span and has the self-anchored suspension bridge for requirement of opening the navigation or air flight under bridge.
Incremental launching method can meet the bridge for having requirement of opening the navigation or air flight under bridge, but there are steel box-girder stress concentrations and slideway to come to nothing
The problems such as, and nose girder height is higher, it is possible to navigational clearance is occupied, to reduce steel box-girder stress, more Temporary Piers need to be set up, no
Suitable for higher ranked self-anchored suspension bridge of opening the navigation or air flight under bridge.
Big segment lifting method can meet navigation requirement temporarily under bridge, and segment lifting construction is relatively simple, due to main girder frame
There are initial internal forces and initial linear after if, though girder can be made to meet design requirement at bridge is linear by the way that girder camber is arranged,
But the influence of initial internal force can not be eliminated, it will lead into main push-towing rope, sunpender etc. after bridge and be unsatisfactory for reasonable finished dead state.
Therefore, it is badly in need of proposing a kind of big segment lifting self-anchored suspension bridge construction method being suitable for not setting camber,
To solve above-mentioned technical problem.
Invention content
In view of above-mentioned, the present invention provides a kind of big segment lifting self-anchored suspension bridge construction method not setting camber,
Reasonable finished dead state can be reached after the completion of construction.
A kind of big segment lifting self-anchored suspension bridge construction method not setting camber, includes the following steps:
(1) according to mould absolute altitude construction bridge tower, auxiliary pier and transition pier, full framing is set up in end bay and anchor span region
Or Temporary Piers, build Temporary Piers in main span region;
(2) stiff girder for not setting camber is inserted on full framing and Temporary Piers, and then full hall branch will be inserted into
Stiff girder welding on frame is integral, and remaining stiff girder is divided into N number of big segment and is lifted to Temporary Piers using crane barge;Institute
It states big segment to connect by temporary support and the Temporary Piers at both ends, to be correspondingly formed two welding at each big segment both ends
Point, N are the natural number more than 0;
(3) apply between stiff girder and bridge tower bottom end rail and between stiff girder and Temporary Piers and indulge bridge to temporary constraint,
And then obtain vertical displacement difference and corner difference between the stiff girder of pad both sides;
(4) for any big segment in stiff girder, the temporary support at the big segment both ends is jacked using jack so that
Stiff girder at the big segment both ends pad returns to unstress state and carries out welding procedure, is fallen after rise after completion;According to above-mentioned
Complete the work progress of all big segment jacking-welding-fallings;
(5) will be on main cable erection to bridge tower and pre- inclined, while main push-towing rope both ends being anchored on the stiff girder of anchor span, it removes vertical
Bridge is to temporary constraint and completes follow-up self-anchored suspension bridge construction.
Further, the auxiliary pier is set on the outside of bridge tower, using it as the segmentation benchmark between end bay and anchor span region;
The transition pier is set on the outside of auxiliary pier, and anchor span is i.e. between auxiliary pier and transition pier.
Further, the decrement for only considering stiff girder when the stiff girder processing on the basis of linear at bridge, without setting
Set camber.
Further, Temporary Piers crest level+temporary support assembly height+stiff girder deck-molding+pavement thickness=at the linear height of bridge
Journey, similarly, full framing crest level+stiff girder deck-molding+pavement thickness=at the linear elevation of bridge.
Further, for freely-supported and there is longitudinal restraint state in N number of big segment of the stiff girder after erection.
Further, after the stiff girder at the pad returns to unstress state, then the adjacent big section in the pad both sides
The vertical displacement difference and corner difference of section are zero, and everywhere pad is required to the process by jacking-welding-falling.
From unstressed theory, the purpose of stiff girder is jacked i.e. so that pad returns to unstress state between segment, is returned
The purpose of stiff girder is fallen i.e. so that stiff girder Internal Force Redistribution;Therefore after the completion of welding procedure, stiff girder internal force and linear it is
One piece falls internal force in the case of frame and linear.
The present invention is not limited to a pad of once only constructing, the construction for being also applied for " multiple pad synchronous constructions " is suitable
Sequence.
The present invention is suitable for " end bay, anchor span, main span are big segment lifting " or " the big segment lifting in part " structure type.
The present invention is suitable for the structure type of only tower, double tower or more tower.
The big segment lifting self-anchored suspension bridge that the present invention is not limited to be constructed by " jacking-welding-falling ", is also applied for it
He uses the big segment lifting self-anchored suspension bridge of unstress state welding.
Construction method of the present invention is easy to operate, is conducive to monitoring, welds girder based on unstress state, can derive a variety of apply
Work scheme is conducive to play large span, the advantage for the self-anchored suspension bridge for having requirement of opening the navigation or air flight under bridge, solve because of construction with brackets
The caused problem that can not open the navigation or air flight temporarily;Compared with traditional " cable after first beam " method, the present invention does not set the big segment lifting of camber certainly
Anchoring type rope-suspension bridge construction is simple is easy, can further promote the competitiveness of large span self-anchored suspension bridge.
Description of the drawings
Fig. 1 is the structural schematic diagram for the big segment lifting self-anchored suspension bridge that the present invention does not set camber.
Fig. 2 is the structural schematic diagram after present invention segment lifting self-anchored suspension bridge construction procedure one greatly.
Fig. 3 is the structural schematic diagram after present invention segment lifting self-anchored suspension bridge construction procedure two greatly.
Fig. 4 is the deformation induced by gravity schematic diagram of stiff girder after big segment lifting.
Fig. 5 is the vertical displacement difference and outer corner difference schematic diagram that a certain pad is read.
Fig. 6 is the linear schematic diagram of stiff girder after the completion of the construction of all pads.
Fig. 7 is the structural schematic diagram after present invention segment lifting self-anchored suspension bridge construction procedure four greatly.
Wherein:1-bridge tower, 21-end bay stiff girders, 22-anchor span stiff girders, 23-main span stiff girders, 231~234-
Main span is put more energy into girder segment, 31-main push-towing ropes, 32-hoist cables, 41-auxiliary piers, 42-transition piers, 51-end bay full framings, and 52-
Anchor span full framing, 6-Temporary Piers, 71~75-indulge bridges to temporary constraint, 8-temporary supports, 91~95-pads.
Specific implementation mode
In order to more specifically describe the present invention, below in conjunction with the accompanying drawings and specific implementation mode is to technical scheme of the present invention
It is described in detail.
As shown in Figure 1, the big segment lifting self-anchored suspension bridge that the present invention does not set camber is double tower five across structure, mainly
Including two bridge towers 1, auxiliary pier 41, transition pier 42, end bay stiff girder 21, anchor span stiff girder 22, main span stiff girder 23, main push-towing rope 31
And hoist cable 32 etc..
Fig. 1 is that self-anchored suspension bridge is constructed later reasonable finished dead state by certain construction method, this is rationally at bridge like
State defines the internal force or linear of component, the main cutting length including main push-towing rope and linear, hoist cable cutting length, girder it is interior
Power and linear, king-tower internal force etc..
It is directed to the self-anchored suspension bridge of raft support method construction, unstress state is in when due to main beam supporting, as long as
Main push-towing rope and hoist cable blanking degree are controlled, then full-bridge is reasonable finished dead state after completion of constructing.Big segment lifting from anchor
Formula suspension bridge, stiff girder when setting up in there is stress state, carry out welding procedure without any processing to stiff girder, it is laggard
Row main cable erection and hoist cable stretching construction, then redistribution occurs for beam stress after stiff girder takes off frame, and hoist cable internal force is caused to occur
Variation, will differ greatly with reasonable finished dead state.The present invention is mainly by jacking segment so that vertical displacement difference at pad
Adjust to zero with corner displacement difference, carried out so that the welding job of the point is under unstress state, especially by with
Lower step is constructed:
Step 1:After mould absolute altitude construction bridge tower 1, auxiliary pier 41 and transition pier 42, end bay full framing 51 is set up
With anchor span full framing 52, main span Temporary Piers 6 are built, as shown in Figure 2.
Step 2:The end bay stiff girder 21 for not setting camber and anchor span stiff girder 22 are inserted on full framing, used
Four segments 231~234 of main span are inserted on Temporary Piers 6 by crane barge, are connected by temporary support 8, at this time between each segment and
There are five pads 91~95 between segment and end bay stiff girder;Construct simultaneously end bay stiff girder 21 and bridge tower bottom end rail and
The vertical bridge of main span stiff girder 23 and Temporary Piers 6 is to temporary constraint 71~75, as shown in Figure 3 and Figure 4.
There is no multiple spot resilient support for anchor span stiff girder 22, therefore the Internal Force Redistribution after de- frame is also not present, while anchor
It is not subject to the axle power effect of main push-towing rope 31 across stiff girder 22, therefore only needs to consider due to dead weight generation when the processing of anchor span stiff girder 22
Amount of deflection;End bay stiff girder 21 and main span stiff girder 23 are acted on by the axle power of main push-towing rope 31, while being constructed by the present invention program
It after process, is not required to that any camber is arranged again, therefore end bay stiff girder 21 and main span stiff girder 23 only need to consider to add in processing
The decrement of strength beam.
The main span stiff girder 23 being inserted on Temporary Piers 6 deforms under Gravitative Loads, as shown in figure 4, each section simultaneously
The internal force distribution of section is simply supported beam pattern, and there are vertical displacement difference and corners between the segment stiff girder at pad at this time
Difference, as shown in Figure 5.
Step 3:By left side bridge tower 1 in Fig. 3, the temporary support 8 of first segment 231 is jacked with jack so that the
Stiff girder returns to unstress state at one pad 91, carries out welding procedure, falls after rise after the completion;Similarly, second section is jacked
232 temporary support 8 so that stiff girder returns to unstress state at the second pad 92, carries out welding procedure, returns after the completion
It falls;The rest may be inferred, construct five pads 95 when, jack the 4th pad 94 at temporary support 8 so that the 5th pad 95
Place's stiff girder returns to unstress state, carries out welding procedure, falls after rise after the completion.
Jack jacks magnitude and is determined by two aspects:On the one hand very heavy as obtained by finite element software construction simulation process
Top jacking magnitude, this calculated value are used as with reference to being worth, for verifying whether vertical displacement difference and corner difference return to zero;On the other hand
Pass through the vertical displacement surveyed when construction and corner monitoring data.
As shown in fig. 6, after main span segment jacking-welding-falling process, linear stiff girder is one continuous linear.Thing
In reality, jacking is the process adjusted at stiff girder pad to unstress state, and welding is to be linked to be the process of continuous beam, and falling is
The internal force distribution of simply supported beam is reassigned into the process that one piece falls the internal force distribution of frame (i.e. continuous beam).
Step 4:By main push-towing rope 31 be inserted on bridge tower 1 and it is pre- while main push-towing rope 31 is anchored to end bay stiff girder 21 partially, tear open
Except vertical bridge is to temporary constraint 7, follow-up self-anchored suspension bridge construction is completed, as shown in Figure 7.
The above-mentioned description to embodiment can be understood and applied the invention for ease of those skilled in the art.
Person skilled in the art obviously easily can make various modifications to above-described embodiment, and described herein general
Principle is applied in other embodiment without having to go through creative labor.Therefore, the present invention is not limited to the above embodiments, ability
Field technique personnel announcement according to the present invention, the improvement made for the present invention and modification all should be in protection scope of the present invention
Within.