CN1458347A - Single stay tensing construction method and apparatus for parallel twisted steel stay system - Google Patents
Single stay tensing construction method and apparatus for parallel twisted steel stay system Download PDFInfo
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- CN1458347A CN1458347A CN 02119646 CN02119646A CN1458347A CN 1458347 A CN1458347 A CN 1458347A CN 02119646 CN02119646 CN 02119646 CN 02119646 A CN02119646 A CN 02119646A CN 1458347 A CN1458347 A CN 1458347A
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- stretch
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Abstract
The construction process includes one single stay tensing step, in which tensing and push pressing seat, jack on the seat, continuous tensing part and tool anchor are used to tense to the designed tension before changing into working clamp sheet, tightening with tightener and once anchoring; and one push pressing step, in which tensing and pushing seat is used as backward force applying frame for the synchronous pushing forward of the clamping sheet and the twisted steel stay. The tensing and pushing seat consists of 3-6 uprights, connecting rings, tensing and pushing board, pressure bearing ring and limiting ring. The said construction method can avoid repeated tensing to result in inevitable hidden fault in anchoring and clamping quality and raise clamping effect and anchoring quality.
Description
One, technical field:
The present invention relates to a kind of parallel steel stranded wire guy system job practices and used aid thereof-a kind of stretch-draw and roof pressure bearing.
Two, background technology:
The parallel steel stranded wire guy system is as the carrying cable body, based on group anchor technology, utilize group anchor clamp to bear a kind of system by drag-line transferring structure sound load with steel strand.The steel strand stay cable system is generally operational in 0.30R
b～0.45R
bThe low stress area, the construction stage only is 0.1R sometimes
bSo anchor clamp anchoring efficient is the key that guarantees guy of twisted steel cable operate as normal under low-stress state.The parallel steel stranded wire suspension cable is generally made at the scene, is installed, and steel strand pass ground tackle by root on the technology, and the stretch-draw pretension is set up initial stress, adjusts to builder's tonnage (also having single stretch-draw repeatedly to reach builder's tonnage) by integral body then.During single pretension, adopted stretch-draw self-anchored method repeatedly in the past---by limiting plate, make when putting intermediate plate with the follow-up of steel strand retraction from anchor.When this technology runs into long rope, the inevitable clamping steel strand repeatedly of work clip sheet, on the one hand, intermediate plate and steel strand are subjected to damage in various degree; On the other hand, drag-line steel strand surface coating for protection against corrosion and iron filings etc. come off and are piled up in the intermediate plate teeth space, influence anchoring effect.
Secondly, parallel steel stranded wire guy system single tendon stretch Suo Li discreteness (uniformity) control is a key point of parallel steel stranded wire guy system, more state's inner control adopts and waits stretching force construction method (gaining public acceptance) construction at present, this method is a sensor installation on first steel strand, control other each root steel twisted-line tension-force with this sensor changing value, though this control technology is ripe, but when specifically implementing, because jack takes up space bigger, many steel strand can't stretch-draw around the sensor, after only removing this sensor, can stretch-draw, this is unfavorable for the control of steel strand uniformity.
The 3rd, can increase intermediate plate to the steel strand chucking power by roof pressure, when single tendon stretch construction at present, when stretch-draw after proof stress, is counter-force by the roof pressure head with these root steel strand, directly work clip sheet is headed in the anchor hole, and way exists following shortcoming: a, intermediate plate to push up motionless in this way; B, intermediate plate be by the jacking anchor hole, but produce relative slippage with steel strand, thereby steel strand and intermediate plate all have scratch in various degree, and intermediate plate interlock again, and with twice bite mark dislocation on the steel strand, both of these case all can influence the grip of intermediate plate.
In sum, single tendon stretch and roof pressure arts demand improve and improve.
Three, summary of the invention:
Technical problem to be solved by this invention is:
In A, the existing parallel steel stranded wire stayed single cable stretching construction, adopt stretch-draw self-anchored method repeatedly, when putting, by limiting plate, make intermediate plate with the follow-up of steel strand retraction, reach from anchor, this worker's method unavoidably occurs: intermediate plate is clamping and scratch steel strand repeatedly, and make intermediate plate be subjected in various degree damage, and casts such as the coating of suspension cable steel strand surface and iron filings are piled up in the intermediate plate teeth space, influence the problem of anchoring effect;
In B, the existing parallel steel stranded wire stayed single cable stretching construction, make the counter-force point with steel strand when roof pressure, make that intermediate plate is relative with steel strand to slide, generation scratch phenomenon influences the problem of anchoring effect.
Its concrete scheme of dealing with problems is: adopt a kind of servicing unit---stretch-draw and roof pressure bearing in parallel steel stranded wire stayed single cable stretching construction, in stretching process, with interim intermediate plate anchoring; Before the last anchoring of steel strand, use the disposable anchoring of formal intermediate plate instead; During roof pressure, utilize bearing, to intermediate plate and the synchronous jacking of steel strand as reaction frame.
Its concrete technical scheme is:
A kind of parallel steel stranded wire guy system single tendon stretch job practices is characterized in that:
In the construction of operations such as single tendon stretch, roof pressure, adopt stretch-draw and roof pressure bearing, its activities comprises:
A: single tendon stretch construction: adopt stretch-draw and roof pressure bearing, jack and continuously tensioning parts are installed at stretch-draw and roof pressure on bearing, interim intermediate plate, tool using anchor repetition stretch-draw anchor are installed, when stretch-draw to design during pulling force, the capable again work clip sheet that changes the outfit, and urgent with urgent device, put a disposable anchoring then;
B: during roof pressure: adopt stretch-draw and roof pressure to make reaction frame with bearing, the synchronous jacking of intermediate plate and steel strand.
The used device of a kind of parallel steel stranded wire guy system single tendon stretch job practices---stretch-draw and roof pressure bearing, constitute by coupling ring, column, stretch-draw top pressing board, bearing ring, spacing ring, described column has 3～6, with 4 is the best, coupling ring, bearing ring lay respectively at the column two ends and fuse by column, spacing ring is fixed on the column by nut, the stretch-draw top pressing board embeds in the seam of bearing ring, coupling ring can be the annular that has internal thread, also can be for having " flange " of screw.
As a kind of pattern of stretch-draw of the present invention and roof pressure usefulness bearing, described stretch-draw top pressing board is the stretch-draw bearing plate, is drilled with the corresponding circular hole of number and position, anchor slab hole on this stretch-draw bearing plate;
As the another kind of pattern of stretch-draw of the present invention and roof pressure usefulness bearing, described stretch-draw top pressing board is the top pressing board that is made of two diaphragms, has equal, the identical semicircle orifice in position of two row's numbers above the every diaphragm.
Parallel steel stranded wire guy system method for stretching of the present invention and stretch-draw thereof and roof pressure have the following advantages with bearing:
1, in the stretching construction, work clip sheet can change the outfit, and accomplish disposable anchoring, avoided occurring when long rope needs stretch-draw repeatedly: intermediate plate is clamping and scratch steel strand and make intermediate plate be subjected in various degree damage repeatedly, and cast such as coating of suspension cable steel strand surface, iron filings is piled up in problems such as bringing anchor clamp anchoring clamping hidden danger of quality in the intermediate plate teeth space, and anchoring effect is good;
2, in the roof pressure process, avoiding with steel strand is roof pressure counter-force point, can apply the jacking power of different tonnages as required to intermediate plate, avoids steel strand and intermediate plate to produce relative slippage and has a negative impact, and improves grip;
3, can make the even jacking of intermediate plate according to the builder's tonnage roof pressure, the intermediate plate interlock is firm, improves interlock degree and chucking power, guarantees anchoring efficient;
4, single load cell can conveniently be installed, not influence the stretch-draw of steel strand on every side, accomplish effectively to control each root steel strand anchorage stress.
5, used servicing unit---stretch-draw and roof pressure are can single tendon stretch dual-purpose with roof pressure with bearing, making the construction simplification, have reduced equipment, increase work efficiency and economic benefit.
Four, description of drawings:
Fig. 1: the present invention's stretch-draw and roof pressure seat structure schematic diagram;
The A of Fig. 2: Fig. 1 is to view;
Fig. 3: the user mode reference diagram when the present invention's stretch-draw and roof pressure are used for single tendon stretch with bearing;
Fig. 4: the user mode reference diagram when the present invention's stretch-draw and roof pressure are used for roof pressure with bearing;
The B of Fig. 5: Fig. 4 is to view.
Fig. 6: the user mode reference diagram when coupling ring is used for roof pressure for " flange " pattern stretch-draw and roof pressure with bearing.
Five: the specific embodiment:
Embodiment:
The single job practices of a kind of parallel steel stranded wire guy system in the single tendon stretch construction, adopts stretch-draw and roof pressure bearing, and its main processes comprises:
A: single tendon stretch construction:
A, bearing and ground tackle are fixedly linked,
B, carry out single steel strand and reeve, and with interim intermediate plate anchoring,
C, single tendon stretch jack and continuously tensioning parts are installed on bearing,
D, utilize space in the bearing, sensor installation on ground tackle,
E, utilize two on single tendon stretch jack and continuously tensioning parts covers moveable anchor repeatedly anchoring steel strand are carried out stretch-draw,
F, stretch-draw use the life's work intermediate plate instead to the disposable anchoring of steel strand during to the design pulling force;
B, steel strand are pursued the root roof pressure: adopt stretch-draw and roof pressure to make reaction frame, make the synchronous jacking of intermediate plate and steel strand, steel strand are pursued the root roof pressure with bearing.
Embodiment two:
A kind of parallel steel stranded wire guy system single tendon stretch job practices equipment therefor---be exclusively used in the stretch-draw and the roof pressure bearing of steel strand tension, as shown in Figure 1, this bearing is by coupling ring 1, column 2, stretch-draw top pressing board 3, bearing ring 4, spacing ring 5 constitutes, described column 2 has 3～6, with 4 is the best, coupling ring 1, bearing ring 4 lays respectively at column 2 two ends and fuses by column 2, spacing ring 5 is fixed on the column 2 by nut, described stretch-draw top pressing board 3 is stretch-draw bearing plates 3, this stretch-draw bearing plate 3 embeds in the seam of bearing ring 4, be screwed, be drilled with the corresponding circular hole of number and position, anchor slab hole on it, have internal thread on the coupling ring 1 of annular, stretch-draw roof pressure bearing links to each other (referring to Fig. 1 with ground tackle by means of this, Fig. 2, Fig. 3).
Embodiment three:
A kind of parallel steel stranded wire guy system single tendon stretch job practices equipment therefor---be exclusively used in the stretch-draw and the roof pressure bearing of steel strand roof pressure, its basic structure is with embodiment two, institute's difference is: described stretch-draw and roof pressure are the diaphragm 12 of two symmetries with the stretch-draw top pressing board in the bearing 3, have equal, the identical semicircle orifice (referring to Fig. 1, Fig. 4, Fig. 5) in position of two row's numbers above the every diaphragm.
As a kind of conversion of various embodiments of the present invention, described coupling ring 1 can be made " flange " pattern, has screw on it, connects (referring to Fig. 6) with bolt with anchor plate or ground tackle.
Installation and application:
In the time of in the single tendon stretch construction, link to each other the coupling ring 1 of stretch-draw and roof pressure bearing fastening with ground tackle, corresponding stretch-draw bearing plate is embedded in the seam, be screwed after the correspondence of adjustment position, Kong Weiyu anchor slab hole, steel strand pass anchor slab and stretch-draw bearing plate, jack and continuously tensioning parts are installed, can single circulation stretch-draw (referring to Fig. 3), when stretch-draw during to the design pulling force, capable again installation work intermediate plate, and urgent with urgent device, put a disposable anchoring then.The clamping anchoring repeatedly of whole stretching process work clip sheet.
When roof pressure, stretch-draw bearing plate 3 is taken out, be inserted in top pressing device 11, and then at the position of stretch-draw top pressing board 3 insertion diaphragm 12, diaphragm 12 provides counter-force (referring to Fig. 4, Fig. 5) for top pressing device 11, after certain root steel strand roof pressure is finished, extracts diaphragm 12 out, can conveniently take out top pressing device, continue next root steel strand of roof pressure.Can steel strand of a roof pressure with this device, also simultaneously 2 of roof pressures with root steel strand at the most.
When wanting sensor installation in the construction, can utilize space between coupling ring and the bearing ring, with the anchor slab supporting-point directly during sensor installation 8 (referring to Fig. 3), and jack tension easily, do not influence the sensor stretching construction of steel strand on every side.
Among Fig. 3, Fig. 4, Fig. 5, Fig. 6:
6-suspension cable ground tackle, 7-steel strand, 8-sensor, 9-continuously tensioning parts,
10-single tendon stretch jack, 11-top pressing device, 12-diaphragm.
Claims (4)
1, a kind of parallel steel stranded wire guy system single tendon stretch job practices is characterized in that: in the single tendon stretch construction, adopt stretch-draw and roof pressure bearing, its main processes comprises:
A: single tendon stretch construction:
A, bearing and ground tackle are fixedly linked,
B, carry out single steel strand and reeve, and with interim intermediate plate anchoring,
C, single tendon stretch jack and continuously tensioning parts are installed on bearing,
D, utilize space in the bearing, sensor installation on ground tackle,
E, utilize two on single tendon stretch jack and continuously tensioning parts covers moveable anchor repeatedly anchoring steel strand are carried out stretch-draw,
F, stretch-draw use the life's work intermediate plate instead to the disposable anchoring of steel strand during to the design pulling force;
B, steel strand are pursued the root roof pressure: adopt stretch-draw and roof pressure to make reaction frame, make the synchronous jacking of intermediate plate and steel strand, steel strand are pursued the root roof pressure with bearing.
2, the used device of a kind of according to claim 1 parallel steel stranded wire guy system single tendon stretch job practices---stretch-draw and roof pressure bearing, it is characterized in that: this bearing is by coupling ring (1), column (2), stretch-draw top pressing board (3), bearing ring (4), spacing ring (5) constitutes, described column (2) has 3～6, coupling ring (1), bearing ring (4) lays respectively at column (2) two ends and fuses by column (2), spacing ring (5) is fixed on the column (2) by nut, stretch-draw top pressing board (3) embeds in the seam of bearing ring (4), coupling ring (1) can be the circular ring type that has internal thread, also can be for having " flange " type of screw.
3, stretch-draw as claimed in claim 2 and roof pressure bearing is characterized in that: the stretch-draw top pressing board (3) of described bearing is stretch-draw bearing plate (3), is drilled with the corresponding circular hole of number and position, anchor slab hole on this stretch-draw bearing plate (3).
4, stretch-draw as claimed in claim 2 and roof pressure bearing, it is characterized in that: the stretch-draw top pressing board (3) of described bearing is the top pressing board that is made of two diaphragms (12), has equal, the identical semicircle orifice in position of two row's numbers above the every diaphragm (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB02119646XA CN100432342C (en) | 2002-05-15 | 2002-05-15 | Single stay tensing construction method and apparatus for parallel twisted steel stay system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB02119646XA CN100432342C (en) | 2002-05-15 | 2002-05-15 | Single stay tensing construction method and apparatus for parallel twisted steel stay system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1458347A true CN1458347A (en) | 2003-11-26 |
| CN100432342C CN100432342C (en) | 2008-11-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB02119646XA Expired - Fee Related CN100432342C (en) | 2002-05-15 | 2002-05-15 | Single stay tensing construction method and apparatus for parallel twisted steel stay system |
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|---|---|
| CN (1) | CN100432342C (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101906884A (en) * | 2010-08-18 | 2010-12-08 | 北京荣大兴业建筑材料有限公司 | Device and method for stretching steel wire rope net |
| CN102277831A (en) * | 2011-05-13 | 2011-12-14 | 大连海事大学 | Stay cable structure for cable-stayed bridge |
| CN102808516A (en) * | 2012-08-23 | 2012-12-05 | 中铁十三局集团有限公司 | Tensioning system |
| CN102953378A (en) * | 2012-12-06 | 2013-03-06 | 中铁四局集团有限公司 | Single-hole double-bundle prestressed anchor rod tensioning device |
| CN103967009A (en) * | 2014-04-29 | 2014-08-06 | 福建华东岩土工程有限公司 | Method for lengthening and tensioning anchor cables |
| CN105507149A (en) * | 2015-11-25 | 2016-04-20 | 安徽金星预应力工程技术有限公司 | Arrangement method for cable-hanging of single parallel steel strand wires |
| CN107747279A (en) * | 2017-08-23 | 2018-03-02 | 柳州欧维姆机械股份有限公司 | A kind of constructing device and implementation engineering method based on group's anchor system single tendon stretch and tune rope |
| CN108589537A (en) * | 2018-04-13 | 2018-09-28 | 江苏法尔胜缆索有限公司 | The single formula external pre-stress bundle construction of reeving of filled-type epoxy coating strand |
| CN109457614A (en) * | 2018-09-30 | 2019-03-12 | 柳州欧维姆结构检测技术有限公司 | Parallel steel stranded wire stayed Cable Construction Suo Li uniformity monitors system and construction method |
| CN111945725A (en) * | 2020-08-04 | 2020-11-17 | 北京市政建设集团有限责任公司 | Prestress intelligent applying system and method for anchor cable supporting structure |
| CN115450435A (en) * | 2022-08-10 | 2022-12-09 | 中交一公局集团有限公司 | Single equal-prestress tensioning device |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3330863A1 (en) * | 1983-09-05 | 1985-03-14 | Magyar Optikai Müvek, Budapest | VERTICAL SHAFT CONSTRUCTION FOR CIRCULAR THEODOLITES WITH TWO DEGREE OF FREEDOM |
| CN2051259U (en) * | 1989-04-29 | 1990-01-17 | 何镇邦 | Stretch device for single reinforcing bar |
| CN2077878U (en) * | 1990-08-31 | 1991-05-29 | 上海市政工程设计院 | Big tonnage cable fastening device |
| CN2399366Y (en) * | 1999-12-31 | 2000-10-04 | 开封科英预应力锚具厂 | Four-action tension jack |
-
2002
- 2002-05-15 CN CNB02119646XA patent/CN100432342C/en not_active Expired - Fee Related
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101906884A (en) * | 2010-08-18 | 2010-12-08 | 北京荣大兴业建筑材料有限公司 | Device and method for stretching steel wire rope net |
| CN101906884B (en) * | 2010-08-18 | 2011-09-28 | 北京荣大兴业建筑材料有限公司 | Device and method for stretching steel wire rope net |
| CN102277831A (en) * | 2011-05-13 | 2011-12-14 | 大连海事大学 | Stay cable structure for cable-stayed bridge |
| CN102277831B (en) * | 2011-05-13 | 2012-12-26 | 大连海事大学 | Stay cable structure for cable-stayed bridge |
| CN102808516A (en) * | 2012-08-23 | 2012-12-05 | 中铁十三局集团有限公司 | Tensioning system |
| CN102953378A (en) * | 2012-12-06 | 2013-03-06 | 中铁四局集团有限公司 | Single-hole double-bundle prestressed anchor rod tensioning device |
| CN103967009A (en) * | 2014-04-29 | 2014-08-06 | 福建华东岩土工程有限公司 | Method for lengthening and tensioning anchor cables |
| CN103967009B (en) * | 2014-04-29 | 2016-03-30 | 福建华东岩土工程有限公司 | A kind of method for the stretch-draw of anchor cable spreading |
| CN105507149A (en) * | 2015-11-25 | 2016-04-20 | 安徽金星预应力工程技术有限公司 | Arrangement method for cable-hanging of single parallel steel strand wires |
| CN107747279A (en) * | 2017-08-23 | 2018-03-02 | 柳州欧维姆机械股份有限公司 | A kind of constructing device and implementation engineering method based on group's anchor system single tendon stretch and tune rope |
| CN107747279B (en) * | 2017-08-23 | 2023-09-12 | 柳州欧维姆机械股份有限公司 | Construction device and implementation method based on group anchor system single tensioning and cable adjusting |
| CN108589537A (en) * | 2018-04-13 | 2018-09-28 | 江苏法尔胜缆索有限公司 | The single formula external pre-stress bundle construction of reeving of filled-type epoxy coating strand |
| CN109457614A (en) * | 2018-09-30 | 2019-03-12 | 柳州欧维姆结构检测技术有限公司 | Parallel steel stranded wire stayed Cable Construction Suo Li uniformity monitors system and construction method |
| CN111945725A (en) * | 2020-08-04 | 2020-11-17 | 北京市政建设集团有限责任公司 | Prestress intelligent applying system and method for anchor cable supporting structure |
| CN115450435A (en) * | 2022-08-10 | 2022-12-09 | 中交一公局集团有限公司 | Single equal-prestress tensioning device |
| CN115450435B (en) * | 2022-08-10 | 2023-10-03 | 中交一公局集团有限公司 | Single equal prestress tensioning equipment |
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| CN100432342C (en) | 2008-11-12 |
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