Based on the construction method for mixing prestressed assembled corrugated steel web plate composite box girder
Technical field
The present invention relates to bridge construction technical field, in advance should based on mixing suitable for large bridge more particularly, to a kind of
The construction method of the assembled corrugated steel web plate composite box girder of power.
Background technology
Traditional prefabricated case beam web is generally concrete material, and not only weight is big and easy to crack, therefore concrete box girder is only suitable for
It is applied to small across footpath(Below 40m)Highway bridge.PC box girder with corrugated steel webs uses the corrugated sheet steel conduct of shearing resistance efficiency high
Web, not only mitigates the deadweight of box beam, and because Wavelike steel webplate is distinctive " fold effect ", prestressing force can efficiently apply
On concrete roof and floor, in recent years in big-and-middle-sized bridge(More than 50m across footpaths)It is upper to be widely applied.
Constructed using the following two kinds form more than existing Wavelike steel webplate PC combined box beams:
A kind of is by the prefabricated concrete roof of the reinforcing bar of whole box girder body, the prefabricated concrete floor of reinforcing bar and Wavelike steel webplate point
For three parts carry out integral prefabricated respectively, lift again afterwards in place, assembly is connected by screw bolts at bridge location.Chinese patent
" pin-connected panel prestressed concrete combined box beam "(Application number 200620126505.3)The prefabricated component of said structure is disclosed, and
Wavelike steel webplate and top board, the connected mode of base plate are highlighted.But, due to the box beam top board of this structure, base plate and
Web is integral structure, and the weight of single prefabricated components is still very heavy.The Wavelike steel webplate case of a width of 16.75m of such as bridge
Beam bridge, its weight per linear meter(lin.m.) is up to more than 10t, even if it is still very difficult to lift single prefabricated components during construction respectively.Its
Secondary, for convenience of transporting, the length of prefabricated components generally will not be very long, and above-mentioned full span erection structure is only limitted to the bridge of small across footpath,
For the bridge of Long span, top board and web still can be using the prefabricated forms of segmentation.In addition, the patent does not account for actually applying
Situations such as applying opportunity of man-hour prestressed strand and reserving hole channel, and also not plus discussed for the treatment measures of hogging moment area,
If lacking the measure of reply beam body loaded deformation and the detailed consideration of Specific construction process aspect, the feasibility of construction is poor.
Another kind is that top board, base plate and Wavelike steel webplate are fixed the precast assembly unit for being linked to be I-shaped structure, at the scene
" two times tensioning is pre- for completion bridge construction such as Chinese patent after the assembled rigid unit of multiple I-shaped structures is carried out into horizontal and vertical splicing
Stress assembled Wavelike steel webplate combination beam and its construction method "(Application number 201510255113.0)Disclose said structure
Transverse H-shaped prefabricated member, and apply secondary prestress in corresponding opportunity, realize the laterally assembled of transverse H-shaped prefabricated member.It is above-mentioned pre-
The assembled rigid unit volume of system is big, tonnage weight(Weight of such as single prefabricated I-shaped unit per linear meter(lin.m.) is up to 5t or so), and
And the stability of itself is also poor, easily causes cost of transportation and hoisting cost rises;To lifting appliance requirement in installation process
Higher, hoisting safety is relatively low.
The content of the invention
The present invention provides a kind of based on the construction method for mixing prestressed assembled corrugated steel web plate composite box girder, purpose
It is that solution existing Wavelike steel webplate PC combined box beams easily occur transporting, lift and later maintenance when being applied to large bridge
Etc. aspect problem.
To achieve the above object, the characteristics of present invention makes full use of corrugated steel web plate composite box girder, in different plates in
Different opportunitys apply prestressing force:For Wavelike steel webplate combination beam, there is the spy of non resistance axle power due to Wavelike steel webplate
Point, the axial force of precast concrete base plate and outer Prestressing can reach over time and space it is natural separate, thus
Can be by the prestressing force single tension of precast concrete base plate to design load;Using the spy of corrugated sheet steel combination beam " weak beam-ends effect "
Linear pattern pretensioned prestressing steel beam is used in point, precast concrete base plate.After the completion of horizontal I-beam assembly is completed, then open
The secondary prestress steel beam of precast concrete base plate and the top board prestressed strand of adjacent across footpath pier top hogging moment area are drawn, specifically may be used
Take following technical proposals:
It is of the present invention based on the construction method for mixing prestressed assembled corrugated steel web plate composite box girder, it is main include with
Lower step:
The first step, by Bridge Design requirement, precast concrete top board, the concrete of independent prefabricated composition i-shaped beamses body unit
Native base plate and Wavelike steel webplate:
For precast concrete top board, first colligation is provided with the roof steel bar of lateral connection muscle, longitudinally connected muscle and peg notch
Net, the peg notch is longitudinally spaced to be arranged on roof steel bar net both sides, then pier top hogging moment prestressed pore passage is arranged on
In roof steel bar net, poured afterwards;
For precast concrete base plate, first pass through tensioning equipment and pretensioned prestressing steel Shu Jinhang tensioning, then colligation are provided with
The baseplate reinforcing bar net of lateral connection muscle, longitudinally connected muscle and peg notch, the peg notch is longitudinally spaced to be arranged on base plate
Bar-mat reinforcement both sides, and baseboard prestress duct is arranged in baseplate reinforcing bar net, installation form, casting concrete, wait to mix afterwards
After solidifying soil reaches design strength, form removal loosens pretensioned prestressing steel beam;
For Wavelike steel webplate, first punch process corrugated sheet steel, then flange plate is welded at corrugated sheet steel two ends, afterwards in the wing
Multigroup spaced peg group is welded on listrium;
Second step, carries out assembled in situ preparation:
Mobile support device is set between the adjacent abutment or bridge pier that complete construction at the scene used as auxiliary construction platform, meanwhile,
By the precast concrete top board of prefabricated completion, precast concrete base plate and corrugated steel web transport to job site;
3rd step, carries out i-shaped beamses body unit and its horizontally-spliced assembling:
Precast concrete base plate is lifted to Mobile support device using hanging device, Wavelike steel webplate is hung in recurrence, and by ripple
Shape steel web bottom peg group is inserted into the peg notch of precast concrete base plate;Afterwards, precast concrete top board is lifted by crane, together
Sample completes the I-shaped beam body of first piece by Wavelike steel webplate top peg group inserting to the peg notch of precast concrete top board
The assembling construction of unit;
Then by Mobile support device along bridge cross direction horizontal transfer, the construction procedure according to first piece i-shaped beamses body unit is complete
The assembling construction of other i-shaped beamses body units transversely set in into the spanning;The adjacent i-shaped beamses body unit of colligation afterwards
Lateral connection muscle between top board, base plate, pours that to form precast concrete top board longitudinal wet joint and precast concrete base plate vertical
To wet seam, the secondary prestress steel Shu Jinhang tensioning in baseboard prestress duct is pointed to afterwards;
4th step, is combined the longitudinal spliced assembling of beam:
Mobile support device is transferred to other spanning positions successively, the 3rd step operation is repeated, each spanning beam body in longitudinal direction is completed
Construction;
Longitudinally connected muscle of the colligation adjacent bridge between top board, base plate, pours to form laterally wet seam or crossbeam, and according to first side
The order of central sill after beam, is pointed in contiguous prefabricated concrete roof pier top hogging moment prestressed pore passage using symmetrical tensioning principle
Tensioning steel Shu Jinhang tensioning, formed continuous beam on many supports system;
5th step, completes the erection of affiliated facility, terminates construction.
Constitute single precast concrete top board, precast concrete base plate and the Wavelike steel webplate of the i-shaped beamses body unit
Length be respectively 5-30 meters.
Construction method based on the prestressed assembled corrugated steel web plate composite box girder of mixing of the present invention, using list
Spelled at the precast concrete top board of only prefabricated i-shaped beamses body unit, precast concrete base plate and Wavelike steel webplate, then scene
Connect the mode of construction.The present invention carries out piecemeal to existing integral prefabricated I-shaped component in a vertical enterprising step, on the one hand
" the fold effect " for taking full advantage of Wavelike steel webplate realizes that box beam breaks the whole up into parts, and prefabricated components volume is fully reduced, and makes structure
Part volume reduces, it is easy to transport and lifting, is conducive to the fast erecting of bridge, while avoiding integral prefabricated I-shaped component
The problem of self stability difference;On the other hand it is also distinctive weak " beam-ends effect " using Wavelike steel webplate, on precast concrete top
The prestressed pore passage for wearing pier top hogging moment tensioning steel beam is provided with plate, is provided with precast concrete base plate and first opened
Method prestressed strand and secondary prestress steel beam, with work progress perfect cooperation, realize the maximum convenient of construction.Wherein, entering
The tensioning of pretensioning steel beam is carried out before row precast concrete base plate, and it is complete horizontal I-beam body unit assembly is completed
Cheng Hou, then tensioning secondary prestress steel beam, the stress for resisting concrete shrinkage and creep generation;Web is by end peg group
Top, the mode in base plate peg notch is inserted into be attached, be connected firmly, construct it is convenient.Adjacent top board and base plate are in bridge
Beam job site can by pour wet seam arrangements carry out splicing laterally and/or longitudinally with obtain the bridge of various requirement it is wide,
Spanning.Specifically, advantages of the present invention can be embodied in it is following some:
(1)The present invention carries out beam body erection using the assembled structure type of precast block, and the volume and weight of each part are all corresponding
It is smaller, stability of the prefabricated component in transportation can not only be effectively ensured, and be easily guaranteed that the peace of component in hoisting process
Quan Xing, beneficial to construction.
(2)The achievable scale of various prefabricated components is prefabricated in the present invention, effectively increases efficiency of construction, shortens construction
Cycle.
(3)The present invention applies different types of prestressing force to top board and base plate on different opportunitys, and all using pre- in vivo
Stress rib, prestress application effect is relatively stable;Due to the deformed bar negligible amounts of tensioning at the scene, therefore construction party
Just, fast.
Brief description of the drawings
Fig. 1 is the structural representation of i-shaped beamses body unit in the present invention.
Fig. 2 is the structural representation of precast concrete top board in Fig. 1.(Omit longitudinally connected reinforcing bar)
Fig. 3 is the structural representation of precast concrete base plate in Fig. 1.(Omit longitudinally connected reinforcing bar)
The structural representation of Wavelike steel webplate in Fig. 4 Fig. 1.
Fig. 5, Fig. 6, Fig. 7 are work progress schematic diagrames.
Fig. 8-13 is the relevant drawings that schematic illustration is carried out to the present invention.
Specific embodiment
Construction method based on the prestressed assembled corrugated steel web plate composite box girder of mixing of the present invention, main bag
Include following steps:
The first step, it is individually prefabricated to constitute i-shaped beamses body unit by Bridge Design requirement(As shown in Figure 1)Precast concrete top
Plate 1, precast concrete base plate 2 and Wavelike steel webplate 3:
Specifically, during prefabricated precast concrete top board 1 as shown in Figure 2, first colligation is provided with lateral connection muscle 1.1, longitudinal direction and connects
The roof steel bar net of muscle and peg notch 1.2 is connect, the peg notch 1.2 is longitudinally spaced to be arranged on roof steel bar net both sides,
Pier top hogging moment prestressed pore passage 1.3 is arranged in roof steel bar net again, is poured afterwards;
During prefabricated precast concrete base plate 2 as shown in Figure 3, first to fix pre-tensioning system pre- the precalculated position on pre-tensioning system stretching bed
Stress steel beam 2.2 is stretched to design load, then colligation is provided with the bottom of lateral connection muscle 2.1, longitudinally connected muscle and peg notch 2.3
Plate bar-mat reinforcement, the peg notch 2.3 is longitudinally spaced to be arranged on baseplate reinforcing bar net both sides, and by baseboard prestress duct 2.4
In baseplate reinforcing bar net, installation form, casting concrete afterwards, after concrete reaches design strength, form removal is put
Loose pretensioned prestressing steel beam 2.2, completes prefabricated, the above-mentioned pretensioned prestressing steel of mixing prestressing force precast concrete base plate 2
Beam 2.2 is used to resist the stress of concrete shrinkage and creep generation;
During prefabricated Wavelike steel webplate 3 as shown in Figure 4, first punch process corrugated sheet steel, then weld the edge of a wing at corrugated sheet steel two ends
Plate 3.1, welds multigroup spaced peg group 3.2 on the flange plate 3.1 afterwards;Above-mentioned peg group 3.2 and top, base plate
On peg notch 1.2,2.3 positions it is corresponding, shape is engaged, and can firmly insert.
Second step, carries out assembled in situ preparation:
Mobile support device is set between the adjacent abutment or bridge pier that complete construction at the scene used as auxiliary construction platform, meanwhile,
The precast concrete top board 1 of prefabricated completion, precast concrete base plate 2 and Wavelike steel webplate 3 are transported to job site.
3rd step, carries out i-shaped beamses body unit and its horizontally-spliced assembling:
Precast concrete base plate 2 is lifted to Mobile support device 4 using hanging device(As shown in Figure 5)On, waveform is hung in recurrence
Steel web 3, and the bottom peg group of Wavelike steel webplate 3 is inserted into the peg notch of precast concrete base plate 2;Afterwards, lift by crane
Precast concrete top board 1, equally inserts in the peg notch of precast concrete top board 1 the top peg group of Wavelike steel webplate 3,
Complete the assembling construction of first piece i-shaped beamses body unit.
Then by Mobile support device 4 along bridge cross direction horizontal transfer, according to the construction of first piece i-shaped beamses body unit
Step completes the assembling construction of other i-shaped beamses body units transversely set in the spanning;The adjacent i-shaped beamses of colligation afterwards
Lateral connection muscle 1.1,2.1 between body unit top, base plate, and pour to form precast concrete top board longitudinal wet joint 5 and pre-
Concrete floor longitudinal wet joint 6 processed(As shown in Figure 6).In order to resist the moment of flexure of second phase load generation, when above-mentioned longitudinal wet connects
After seam reaches some strength, the secondary prestress steel Shu Jinhang that need to be pointed in baseboard prestress duct 2.4 is stretched to design load.
The i-shaped beamses body unit of above-mentioned lateral connection can constitute single chamber structure as shown in Figure 6, also can continuously splice
The double chambers of composition or many chamber structures.
4th step, is combined the longitudinal spliced assembling of beam:
Mobile support device 4 is transferred to other spanning positions successively, the 3rd step operation is repeated, each spanning beam body in longitudinal direction is completed
Construction;
Longitudinally connected muscle of the colligation adjacent bridge between top, base plate, pours to form laterally wet seam or crossbeam 7(As shown in Figure 7);
In order to resist the pier top hogging moment of adjacent across footpath box beam, when laterally wet seam or crossbeam 7 reach some strength, according to first side bar
The order of central sill, contiguous prefabricated concrete roof pier top hogging moment prestressed pore passage 1.3 is pointed to using symmetrical tensioning principle afterwards
Interior tensioning steel Shu Jinhang tensioning, forms continuous beam on many supports system;
5th step, completes the erection of affiliated facility, terminates construction.
In order to reduce the workload of the wet seam of cast in situs, efficiency of construction is improved, constitute the single of i-shaped beamses body unit
The length of precast concrete top board 1, precast concrete base plate 2 and Wavelike steel webplate 3 is respectively 5-30 meters.
Vertically spliced the following is to Wavelike steel webplate built H beam of the present invention, applied mixing this construction of prestressing force
The concrete principle explanation that the feasibility of method, reasonability are made:
Stress of the precast concrete base plate under two states is analyzed first.
1. the 1st state:
Precast concrete base plate as shown in Figure 8, the prestressing force that the stretch-draw prestressing force steel beam set in it is applied is N, then in advance
Section upper stress on concrete floor processed is:
2. the 2nd state:
When above-mentioned precast concrete floor combination turns into I-shaped Wavelike steel webplate combination beam, its I-shape cross section structure is as schemed
Shown in 9.
Apply prestressing force N on precast concrete base plate, the moment of flexure to compound section neutral axis is:
Obtained by the area moment of upper lower section is equal:
The area of combination beam total cross-section is:
The moment of inertia of whole cross section is:
Wavelike steel webplate combination beam can not consider the work of web when anti-bending bearing capacity is calculated due to the non resistance axle power of web
With equivalent to without web plate section, therefore setting:
Then:
The stress of top board:
Make ratio of height to thickness
The then stress of top board:
The stress of base plate:
Have for general combination beam section, can obtain
By taking the Wavelike steel webplate combination beam of 30m across footpaths as an example.If, now, bring formula into(9)With(10):
When the across footpath of bridge further increases,WithFurther increase, formula(10)Meet
As can be seen here, under the 1st state and the 2nd state, the stress approximately equal of precast concrete base plate.That is, existing in advance
The prestressing force that the prefabricated panel stage applies, is still held essentially constant after Wavelike steel webplate combination beam is overlapped into.Therefore waveform is claimed
Steel web combination beam take it is vertical layered it is assembled before and after this mechanical characteristics that can be held essentially constant of stress for co-bearing not
Denaturation.This characteristic provides the foundation for the vertical layered splicing of Wavelike steel webplate combination beam.
On the basis of above-mentioned analysis, ordinary steel-mixed built H beam and Wavelike steel webplate built H beam is back to discuss
Vertical fractionation with assembly during stress change.Wherein, using prestressing force as only consideration external force:
1. vertical split process:
Figure 10 is the schematic diagram that ordinary steel-mixed built H beam carries out vertical fractionation.
Figure 11 is the schematic diagram that Wavelike steel webplate built H beam carries out vertical fractionation.
2. prestressing force+vertical splicing is mixed:
Schematic diagram when Figure 12 is ordinary steel-mixed built H beam applying mixing prestressing force and vertical splicing.
Figure 13 is schematic diagram when Wavelike steel webplate built H beam applies mixing prestressing force and vertically splices.
Contrast above-mentioned legend to can be seen that for Wavelike steel webplate built H beam, prestressing force is applied just in base plate
It seem an independent process;But the situation of ordinary steel-mixed combination is entirely different.Therefore, can be prefabricated in construction
Apply all or part of prestressing force during concrete floor, then by precast concrete base plate, Wavelike steel webplate and precast concrete
The vertical layered assembly of top board, can so greatly reduce the steel Shu Zhangla workloads at scene, improve factory prefabricating degree.