CN110820601B - Longitudinal constraint and displacement control method for large-span continuous steel truss girder cable-stayed bridge - Google Patents
Longitudinal constraint and displacement control method for large-span continuous steel truss girder cable-stayed bridge Download PDFInfo
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- CN110820601B CN110820601B CN201911021900.3A CN201911021900A CN110820601B CN 110820601 B CN110820601 B CN 110820601B CN 201911021900 A CN201911021900 A CN 201911021900A CN 110820601 B CN110820601 B CN 110820601B
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 48
- 239000010959 steel Substances 0.000 title claims abstract description 48
- 238000006073 displacement reaction Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 29
- 238000006243 chemical reaction Methods 0.000 claims abstract description 5
- 238000009434 installation Methods 0.000 claims description 5
- 238000004873 anchoring Methods 0.000 claims description 2
- 230000006835 compression Effects 0.000 claims 2
- 238000007906 compression Methods 0.000 claims 2
- 238000010276 construction Methods 0.000 abstract description 12
- 230000008569 process Effects 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 230000008859 change Effects 0.000 description 4
- 230000000452 restraining effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000003139 buffering effect Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D21/00—Methods or apparatus specially adapted for erecting or assembling bridges
- E01D21/10—Cantilevered erection
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D11/00—Suspension or cable-stayed bridges
- E01D11/04—Cable-stayed bridges
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D19/00—Structural or constructional details of bridges
- E01D19/14—Towers; Anchors ; Connection of cables to bridge parts; Saddle supports
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
- E01D21/00—Methods or apparatus specially adapted for erecting or assembling bridges
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Abstract
The invention discloses a longitudinal restraint and displacement control method for a large-span continuous steel truss girder cable-stayed bridge, which is characterized in that a restraint limiting rod is hinged with supporting seats at two ends of the restraint limiting rod to realize the purpose of longitudinal limitation; releasing the restraint at one end of the restraint limiting rod, and pushing the restraint limiting rod by using a jack to achieve the purpose of longitudinal displacement of the bridge; the invention can simultaneously complete the longitudinal restraint limit, the closure state adjustment and the conversion of the closure rear bridge system in the continuous steel truss girder cable-stayed bridge construction process. The device has the advantages of simple structure, convenience in manufacture, good applicability, simplicity and convenience in operation and the like, and effectively solves the technical problems in the process of cantilever erection and closure construction of the large-span continuous steel truss girder cable-stayed bridge.
Description
Technical Field
The invention belongs to the field of bridge construction, and particularly relates to a longitudinal restraint and displacement control method for a large-span continuous steel truss cable-stayed bridge, which is mainly used for restraining the longitudinal displacement of the bridge and adjusting the closure state of the bridge in the cantilever erection construction process of the large-span continuous steel truss cable-stayed bridge.
Background
The cantilever erection is a main construction method of a large-span continuous steel truss girder cable-stayed bridge, and in the cantilever erection process, due to the fact that the length of a cantilever is large, the integral rigidity of the bridge is small, the structural stability is poor, and meanwhile, the bridge is influenced by environmental factors (wind, temperature and the like) and construction load, longitudinal deviation of the bridge occurs, longitudinal restraint needs to be carried out on the bridge in the construction process, but meanwhile, the cantilever erection method needs to adapt to micro displacement caused by bridge temperature change, and also needs to meet the requirement of typhoon resistance in a large cantilever state; when the steel truss girder is erected to the closure stage, the bridge needs to be longitudinally shifted and adjusted to meet the closure requirement; after closure is completed, when constraint release and bridge-forming system conversion are carried out, the bridge is prevented from being damaged by sudden change of internal and external loads.
Disclosure of Invention
The invention aims to solve the problems and provides a method for controlling longitudinal restraint and displacement of a large-span continuous steel truss girder cable-stayed bridge, which simplifies the operation procedures of the conventional continuous steel truss girder cable-stayed bridge, such as cantilever erection longitudinal restraint, span-center closure state adjustment and post-bridge restraint release; the device has the advantages of simple structure, convenience in manufacture, good applicability, simplicity and convenience in operation, low investment cost, good popularization prospect and the like.
The invention solves the technical problem and provides a method for controlling longitudinal restraint and displacement of a large-span continuous steel truss girder cable-stayed bridge, which comprises the following steps:
step one, when a continuous steel beam cable-stayed bridge is erected to a cantilever stage, beam end supporting seats (1) and tower end supporting seats (2) are respectively installed at the lower chord of a steel truss beam and the top of a main tower beam at the main tower of the cable-stayed bridge, and a constraint limiting rod (4) is respectively hinged with the beam end supporting seats (1) and the tower end supporting seats (2) through a pin shaft (3) so as to limit the bridge.
And step two, installing an elastic buffer cushion block (5) in a gap between the pin shaft (3) and the pin hole of the restraint limiting rod in the step one so as to buffer the impact of the displacement of the bridge.
And step three, when the continuous steel truss girder cable-stayed bridge is erected to a midspan closure stage, mounting counter-force seats (6) at two sides of the hinged part of the constraint limiting rod (4) and the tower end supporting seat (2) in the step one.
And step four, disassembling the elastic buffer cushion block (5) in the step two and the tower end hinged pin shaft (3) in the step one, replacing the installation pin shaft (7), wherein the diameter of the installation pin shaft (7) is smaller than that of the pin shaft (3) in the step one, and the diameter of the installation pin shaft (7) is determined according to the displacement of the steel truss bridge required to move.
And fifthly, a jack is arranged between the counter-force seats (6) in the third step, the jack is driven to enable the steel truss girder to move for a certain displacement, and after the requirement is met, a crescent cushion block (8) is arranged at the top core position of the jack to be locked and positioned.
And step six, after the midspan closure of the continuous steel truss girder cable-stayed bridge is finished, removing the crescent cushion blocks (8), slowly releasing the jacks to gradually restore the whole bridge to the original position, removing the mounting pin shafts (7) and removing the longitudinal constraint.
The longitudinal restraint and displacement control method of the large-span continuous steel truss cable-stayed bridge comprises the step one that a beam end support seat (1), a tower end support seat (2), a pin shaft (3) and a restraint limiting rod (4) are symmetrically arranged on two sides of the steel truss cable-stayed bridge.
The longitudinal restraint and displacement control method of the large-span continuous steel truss girder cable-stayed bridge comprises the following steps that firstly, a beam end supporting seat (1) is installed on a lower chord member through a high-strength bolt; step one, the tower end supporting seat (2) is installed on an embedded anchoring seat on the top of a main tower beam through a high-strength bolt, so that firmness and reliability are guaranteed.
According to the method for controlling longitudinal restraint and displacement of the large-span continuous steel truss cable-stayed bridge, pin holes are machined in ear plates at two ends of a restraint limiting rod (3) in the first step, a long round hole is machined in one end connected with the tower end supporting seat (2) in the first step, and the requirements of the steel truss cable-stayed bridge on temperature deformation and installation requirements in the second step are met through the elastic buffer cushion block (5).
According to the longitudinal restraining and displacement control method for the large-span continuous steel truss girder cable-stayed bridge, a certain pre-pressing/pulling force is applied to the restraining limiting rod (4) in the step one before the step four is carried out, and after the step four is completed, the pre-pressing/pulling force is slowly released.
And the longitudinal constraint and displacement control method for the large-span continuous steel truss girder cable-stayed bridge comprises the fifth step and the sixth step, wherein the driving jack is gradually pressed or released in a segmented and graded manner, so that the safety and stability of the steel truss girder bridge structure are ensured.
The invention at least comprises the following advantages:
firstly, the structure is simple: the device consists of a supporting seat, a constraint limiting rod and a pin shaft;
secondly, the operation is simple and convenient: the supporting seat of the device is connected with the main structure by bolts; the constraint limiting rod is hinged with the supporting seats at the two ends of the constraint limiting rod through a pin shaft; the operation is simple, convenient and quick.
Thirdly, safety and reliability: the device adopts elastic buffer to restrain and limit, adapts to the wriggle generated by the temperature change of the beam body, plays a role in reasonably distributing the internal force of the structure under the action of typhoon in a large cantilever state, plays a role in buffering the beam body and ensures the safety of the bridge structure.
Fourthly, the investment cost is low: the device has the functions of longitudinal constraint and limit, closure state shift adjustment and whole bridge system slow release conversion, simplifies the construction process compared with the traditional construction method, and shortens the construction period.
Fifth, the popularization prospect is good: the simple and convenient and fast restraining and shifting method is provided for the construction of bridges with similar structures, the superior technical advantages and the good economy are displayed, and the popularization prospect is good.
Drawings
Fig. 1 is a schematic diagram of longitudinal restraint limit of the present invention.
FIG. 2 is a schematic diagram of the tower end elastic buffering and partial enlargement of the present invention.
FIG. 3 is a side view and a top view of the longitudinal shift adjustment of the present invention.
FIG. 4 is a schematic diagram of the present invention showing the change of the longitudinal shift position.
In the above drawings, the corresponding component names are as follows:
1-beam end supporting seat; 2-tower end supporting seat; 3, a pin shaft; 4-restraining the limiting rod;
5, elastic buffer cushion blocks; 6-counter-force seat; 7, mounting a pin shaft; 8-crescent cushion block
Detailed Description
Referring to the attached drawings, a method for controlling longitudinal restraint and displacement of a large-span continuous steel truss girder cable-stayed bridge comprises the following steps:
step one, when a continuous steel beam cable-stayed bridge is erected to a cantilever stage, beam end supporting seats (1) and tower end supporting seats (2) are respectively installed at the lower chord of a steel truss beam and the top of a main tower beam at the main tower of the cable-stayed bridge, and a constraint limiting rod (4) is respectively hinged with the beam end supporting seats (1) and the tower end supporting seats (2) through a pin shaft (3) so as to limit the bridge.
And step two, installing an elastic buffer cushion block (5) in a gap between the pin shaft (3) and the pin hole of the constraint limiting rod to buffer the impact of the displacement of the bridge.
And step three, when the continuous steel truss girder cable-stayed bridge is erected to the midspan closure stage, the counterforce seats (6) are arranged on two sides of the hinged position of the constraint limiting rod (4) and the tower end supporting seat (2).
And step four, dismantling the elastic buffer cushion block (5) and the tower end hinged pin shaft (3) in the step one, replacing the mounting pin shaft (7), wherein the diameter of the mounting pin shaft (7) is smaller than that of the pin shaft (3) in the step one, and the diameter of the mounting pin shaft (7) is determined according to the displacement of the steel truss bridge required to move.
And fifthly, arranging a jack between the counter-force seats (6), driving the jack to enable the steel truss girder to move for a certain displacement, and after the requirement is met, locking and positioning by arranging a crescent cushion block (8) at the position of the jack core of the jack.
And step six, after the midspan closure of the continuous steel truss girder cable-stayed bridge is finished, removing the crescent cushion blocks (8), slowly releasing the jacks to gradually restore the whole bridge to the original position, removing the mounting pin shafts (7), removing the longitudinal constraint, removing the supporting seats (1) and (2), and finishing the longitudinal constraint, the displacement and the system conversion after closure in the construction process of the large-span continuous steel truss girder cable-stayed bridge.
Claims (6)
1. A method for controlling longitudinal restraint and displacement of a large-span continuous steel truss girder cable-stayed bridge is characterized in that a restraint limiting rod is hinged with supporting seats at two ends of the restraint limiting rod to achieve the purpose of longitudinal restraint; the restraint of one end of the restraint limiting rod is released, the restraint limiting rod is pushed by a jack, and the purpose of longitudinal displacement of the bridge is achieved, and the method comprises the following steps:
step one, when a continuous steel beam cable-stayed bridge is erected to a cantilever stage, respectively installing a beam end supporting seat (1) and a tower end supporting seat (2) at the lower chord of a steel truss and the top of a main tower beam at a main tower of the cable-stayed bridge, and respectively forming hinged connection between a constraint limiting rod (4) and the beam end supporting seat (1) and the tower end supporting seat (2) by adopting a pin shaft (3) so as to realize longitudinal limitation of the bridge;
step two, installing an elastic buffer cushion block (5) in a gap between the pin shaft (3) and the pin hole of the restraint limiting rod in the step one so as to buffer the impact of the displacement of the bridge;
step three, when the continuous steel truss girder cable-stayed bridge is erected to a midspan closure stage, reaction seats (6) are arranged on two sides of the hinged position of the restraint limiting rod (4) and the tower end supporting seat (2) in the step one;
step four, dismantling the elastic cushion block (5) in the step two to release longitudinal restraint; dismantling the tower end hinged pin shaft (3) in the first step, and replacing the mounting pin shaft (7), wherein the diameter of the mounting pin shaft (7) is smaller than that of the pin shaft (3) in the first step, and the diameter of the mounting pin shaft (7) is determined according to the displacement of the steel truss bridge required to move;
fifthly, a jack is arranged between the counter-force seats (6) in the third step, the jack is driven to enable the steel truss girder to move for a certain displacement, and after the requirement is met, a crescent cushion block (8) is arranged at the top core position of the jack to be locked and positioned, so that the longitudinal displacement of the bridge is completed;
and step six, after the midspan closure of the continuous steel truss girder cable-stayed bridge is finished, removing the crescent cushion blocks (8), slowly releasing the jacks to gradually restore the whole bridge to the original position, removing the mounting pin shafts (7) and removing the longitudinal constraint.
2. The method for controlling longitudinal restraint and displacement of the large-span continuous steel truss girder cable-stayed bridge according to claim 1, wherein the beam end supporting seat (1), the tower end supporting seat (2), the pin shaft (3) and the restraint limiting rod (4) are symmetrically arranged on two sides of the steel truss girder bridge in the step one.
3. The method for controlling longitudinal restraint and displacement of a large-span continuous steel truss cable-stayed bridge according to claim 1, wherein the step one is that the beam end support base (1) is installed on a lower chord member through a high-strength bolt; step one, the tower end supporting seat (2) is installed on an embedded anchoring seat on the top of a main tower beam through a high-strength bolt, so that firmness and reliability are guaranteed.
4. The method for controlling longitudinal restraint and displacement of a large-span continuous steel truss cable-stayed bridge according to claim 1, wherein pin holes are processed on ear plates at two ends of the restraint limiting rod (4) in the first step, and a long round hole is processed at one end connected with the tower-end supporting seat (2) in the first step, so that the requirements of the elastic cushion block (5) in the second step of temperature deformation and installation of the steel truss cable-stayed bridge are met.
5. The method for controlling longitudinal restraint and displacement of a large-span continuous steel truss girder cable-stayed bridge according to claim 1, wherein a certain longitudinal pre-compression/tension should be applied to the restraint limiting rod (4) of the first step before the fourth step, and the pre-compression/tension is slowly released after the fourth step.
6. The method as claimed in claim 1, wherein the driving jack is gradually pressed or released in stages to ensure the safety and stability of the steel truss bridge structure.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911021900.3A CN110820601B (en) | 2019-10-24 | 2019-10-24 | Longitudinal constraint and displacement control method for large-span continuous steel truss girder cable-stayed bridge |
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| CN201911021900.3A CN110820601B (en) | 2019-10-24 | 2019-10-24 | Longitudinal constraint and displacement control method for large-span continuous steel truss girder cable-stayed bridge |
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| CN109778708A (en) * | 2019-03-05 | 2019-05-21 | 中铁四局集团有限公司 | Mid-span closure longitudinal deviation rectifying device of large-span continuous steel truss cable-stayed bridge |
| CN111395153B (en) * | 2020-03-07 | 2021-05-28 | 中交第二公路勘察设计研究院有限公司 | Vertical buffering anti vibration is roof beam device even |
| CN111519536B (en) * | 2020-04-15 | 2021-10-19 | 中铁大桥局集团有限公司 | Closure method for midspan steel box girder of cable-stayed bridge of large-span floating system |
| CN112982180B (en) * | 2021-05-18 | 2021-08-24 | 中铁大桥科学研究院有限公司 | Intelligent monitoring method for stage construction of ultra-large span cable-stayed bridge |
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| CN109778708A (en) * | 2019-03-05 | 2019-05-21 | 中铁四局集团有限公司 | Mid-span closure longitudinal deviation rectifying device of large-span continuous steel truss cable-stayed bridge |
| CN209508820U (en) * | 2018-12-11 | 2019-10-18 | 中铁四局集团有限公司 | Mid-span closure longitudinal deviation rectifying device of large-span continuous steel truss cable-stayed bridge |
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| CN201250386Y (en) * | 2008-09-10 | 2009-06-03 | 中铁八局集团第一工程有限公司 | Rocker-bar bearing for resisting wind and provisionally buttressing in cable-stayed bridge cantilever construction |
| CN103806370B (en) * | 2014-02-12 | 2016-04-06 | 郑州市市政工程总公司 | Steel box-girder overturn-preventing structure |
| CN105839516B (en) * | 2016-06-07 | 2017-06-23 | 长安大学 | A kind of bridge lateral anti-fall girder apparatus and its construction method |
| CN205711703U (en) * | 2016-06-07 | 2016-11-23 | 长安大学 | A kind of bridge lateral anti-fall girder apparatus |
| CN106049257A (en) * | 2016-08-02 | 2016-10-26 | 大连海事大学 | Longspan cable-stayed bridge aseismic structure provided with buckling restrained braces |
| CN208167494U (en) * | 2018-03-16 | 2018-11-30 | 上海市城市建设设计研究总院（集团）有限公司 | Transverse direction suitable for cable-stayed bridge, suspension bridge subtracts shock insulation combination unit |
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| CN209508820U (en) * | 2018-12-11 | 2019-10-18 | 中铁四局集团有限公司 | Mid-span closure longitudinal deviation rectifying device of large-span continuous steel truss cable-stayed bridge |
| CN109778708A (en) * | 2019-03-05 | 2019-05-21 | 中铁四局集团有限公司 | Mid-span closure longitudinal deviation rectifying device of large-span continuous steel truss cable-stayed bridge |
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Effective date of registration: 20210624 Address after: No.96, Wangjiang East Road, Baohe District, Hefei City, Anhui Province, 230041 Applicant after: CHINA TIESIJU CIVIL ENGINEERING GROUP Co.,Ltd. Applicant after: China Railway Fourth Bureau Group Steel Structure Construction Co.,Ltd. Applicant after: CHINA RAILWAY FIFTH SURVEY AND DESIGN INSTITUTE GROUP Co.,Ltd. Address before: CHINA TIESIJU CIVIL ENGINEERING GROUP Co.,Ltd. Applicant before: CHINA TIESIJU CIVIL ENGINEERING GROUP Co.,Ltd. Applicant before: China Railway Fourth Bureau Group Steel Structure Construction Co.,Ltd. |
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