CN2739290Y

CN2739290Y - Steel strand vertical prestress anchoring system

Info

Publication number: CN2739290Y
Application number: CN 200420013607
Authority: CN
Inventors: 李国平; 谢正元; 朱万旭; 蒋业东
Original assignee: Tongji University; Liuzhou OVM Machinery Co Ltd
Current assignee: Tongji University; Liuzhou OVM Machinery Co Ltd
Priority date: 2004-09-18
Filing date: 2004-09-18
Publication date: 2005-11-09
Anticipated expiration: 2014-09-18

Abstract

A steel strand vertical prestress anchoring system relates to a prestressing anchorage system including a fixed end, a stretching end and a prestressing tendon. The steel strand vertical prestress anchoring system is characterized in that the prestressing tendon is a steel wire (5); the fixed end is composed of a compression anchor (1), a fixed end anchorage plate (2); the stretching end is composed of an end anchorage shim plate (6), a clamp nut (7), a work anchor plate (8) and a clamping piece (9). The small end of the anchoring shim plate is sheathed in the corrugated pipe. The clamp nut presses on the anchoring shim plate. The cylindrical work anchor plate connects fixedly with the clamp nut through the external screw thread. One end of the fixed-length steel wire runs through the anchor span of the fixed end anchorage plate and is fixed to the fixed end anchorage plate through the compression of the compression anchor. The other end of the steel wire is fixed on the work anchor plate at the stretching end through the clamping piece. The anchoring system has the advantages that small prestress retracting loss, capability of abating self-weight of components, good anti-fatigue property, small effect to the hardness and intensity of components, and capability of improving the safety stability of components. The steel strand vertical prestress anchoring system is the suitable for the web plate of the prestressed concrete bridge.

Description

Vertical steel strand pre-stressed anchored system

Technical field

The utility model relates to a kind of prestress anchorage system, particularly a kind of vertical steel strand pre-stressed anchored system.

Background technology

In continuous beam or the continuous steel structure of prestressed concrete bridge, because the needs of shearing resistance are typically provided with the vertical prestressing system in the bridge web.Existing vertical prestressing anchoring system is generally by finish rolling deformed bar 25, be screwed in the post tensioning prestress system that nut 21 on the finish rolling deformed bar and anchor plate 22 are formed, between the anchor plate of two ends He outside the finish rolling deformed bar, bellows 24 is arranged, all be placed with spiral bar 23 below the anchor plate of two ends, by tensioning equipment finish rolling deformed bar is carried out stretch-draw, after stretch-draw is finished, nut 21 is tightened, be pressed into cement paste 26 by madjack pipe 27 and stack 28 at bellows 24 and 25 of finish rolling deformed bars, the retraction that stops finish rolling deformed bar by anchor plate and concrete foundation, thereby introducing prestressing force, essential structure is referring to shown in Figure 5, this technical pattern is simple, easy to operate, but following deficiency is also arranged:

1, the screw thread of finish rolling deformed bar is rolling forming, and accuracy of thread is relatively poor, and screw thread unavoidably produces moderate finite deformation when putting, contacts badly with nut, and it is non-constant to cause amount of recovery to reach retraction greatly, causes the vertical prestressing weak effect;

2, the shared sectional area of this system is bigger, influences the strength and stiffness of member, and it is unfavorable to cause member;

3, because the intensity and the diameter of rolling finish rolling deformed bar are limited, it is very little to make it the prestressing force that applies by it, and applicable prestressing force scope is less;

4, finish rolling deformed bar is by the rolling rigid body that forms of factory, owing to reason length such as transportation are restricted; When need are used long presstressed reinforcing steel, need coupling to carry out spreading;

5, finish rolling deformed bar is a rigid body, and diameter is bigger, and the grouting back is relatively poor with the globality of member.

The utility model content

The technical problems to be solved in the utility model is: existing by finish rolling deformed bar, it is non-constant to be screwed in the above-mentioned reinforcing bar retraction that rigidity vertical prestressing anchoring system that nut on the finish rolling deformed bar and anchor plate form exists, elongation during stretch-draw seldom, the shared sectional area of system is bigger, the strength and stiffness and the loss of ground tackle retraction that influence member are bigger, the vertical prestressing effect is relatively poor, with concrete binding, the problem that the effect of bonding is not so good, providing a kind of is presstressed reinforcing steel with steel strand, it is little to have the loss of prestressing force retraction, can reduce member dead weight, anti-fatigue performance is good, and is little to the rigidity and the intensity effect of member, can improve the vertical steel strand pre-stressed anchored system of the security and stability of member.

The technical scheme that solves its above-mentioned technical problem is: a kind of vertical steel strand pre-stressed anchored system; comprise fixed end; the stretch-draw end; presstressed reinforcing steel; be connected with bellows between fixed end and the stretch-draw end; form airtight protection duct; the spiral bar that booster action has been arranged under the anchor plate of two ends; it is characterized in that: described presstressed reinforcing steel is steel strand; described fixed end is by the extruding anchor; the fixed end anchor slab constitutes; described stretch-draw end is by stretch-draw end anchor plate; clamp nut; the work anchor slab; intermediate plate is formed; the anchor plate small end is enclosed within the bellows; clamp nut is pressed on the anchor plate; columniform work anchor slab is connected and fixed by external screw thread and clamp nut; the anchor hole that steel strand one end of fixed length passes the fixed end anchor slab is fixed on fixed end anchor slab place by the extruding of extruding anchor, and the other end of steel strand is anchored on the work anchor slab of stretch-draw end by intermediate plate.

Owing to adopt said structure, the vertical steel strand pre-stressed anchored system of the utility model is compared with the post tensioning vertical prestressing anchoring system that anchor plate is formed by finish rolling deformed bar, the nut that is screwed on the finish rolling deformed bar with existing, has following beneficial effect:

1, used binding thread is become by the machine car, the precision height, and amount of recovery is few, has reduced the loss of prestressing force retraction;

2, used presstressed reinforcing steel is steel strand, and its intensity height can reduce member dead weight, economical with materials under the identical prestressing force situation; Anti-fatigue performance is good, can improve the security and stability of member;

3, the counter-bending rigidity of steel strand is low, and flexibility is good, reel transportation, and length is unrestricted, is convenient to the application of long presstressed reinforcing steel and sets up, and does not need coupling;

4, steel strand can be single with jack pretension or manual pretension, and stress is even;

5, the duct cross-sectional area is little, and is little to the rigidity and the intensity effect of member;

6, the steel strand cross-sectional area as presstressed reinforcing steel is little, disperses to arrange, and is beneficial to combination, improves the globality of presstressed reinforcing steel and member.

Description of drawings:

Fig. 1, Fig. 2: it " vertical steel strand pre-stressed anchored system " structure of the utility model and stretching construction connection diagram;

Fig. 3, Fig. 4:: it " vertical steel strand pre-stressed anchored system " structural representation of the utility model after the sealing off and covering anchorage grouting;

Fig. 5: existing vertical prestressing anchoring system structural representation.

The specific embodiment:

A kind of vertical steel strand pre-stressed anchored system; comprise fixed end; the stretch-draw end; presstressed reinforcing steel; be connected with bellows 4 between fixed end and the stretch-draw end and form airtight protection duct; the spiral bar 3 that booster action has been arranged under the anchor plate of two ends; described presstressed reinforcing steel is steel strand 5; described fixed end is by extruding anchor 1; fixed end anchor slab 2 constitutes; described stretch-draw end is by stretch-draw end anchor plate 6; clamp nut 7; work anchor slab 8; intermediate plate 9; stretch-draw tube 10 is formed; anchor plate 6 small ends are enclosed within the bellows; clamp nut 7 is pressed on the anchor plate 6; columniform work anchor slab 8 is connected and fixed by external screw thread and clamp nut 7; the anchor hole that steel strand 5 one ends of fixed length pass fixed end anchor slab 2 is fixed on fixed end anchor slab place by 1 extruding of extruding anchor; the other end of steel strand 5 is anchored at by intermediate plate 9 on the work anchor slab 8 of stretch-draw end (referring to Fig. 1); among the figure: 10---the stretch-draw tube; 11---mortar, 12---madjack pipe; 13---stack.

In the construction, construct according to a conventional method and lay the anchoring system of the utility model, after concrete members reaches design stretch-draw requirement, with stretch-draw tube 10 1 ends and work anchor slab 8 by thread connection (referring to Fig. 1), the other end is fixed on the stretch-draw jack, during stretch-draw, make the steel strand integral bundle stretching extension, and drive the work anchor slab and clamp nut moves together by the effect of stretch-draw tube, after stretch-draw puts in place, tighten clamp nut, thereby stoped the retraction of steel strand, introduce prestressing force.

After stretch-draw is finished, by grout pipe and stack to carrying out perfusion mortar 11 in the bellows, so that presstressed reinforcing steel and member form whole and presstressed reinforcing steel is formed protection; At last the stretch-draw end is carried out sealing off and covering anchorage operation (as Fig. 3, Fig. 4), Fig. 3 arrives mortar 14 landfills in the stretch-draw groove during sealing off and covering anchorage for reserving the stretch-draw groove; Fig. 4 is not for reserving the stretch-draw groove; by protective cover 15 is installed, perfusion mortar 14 in protective cover forms the protection to the stretch-draw end then.

As a kind of conversion of the utility model embodiment, also have a truncated cone-shaped groove on the described work anchor slab 8, anchor hole is opened on groove, is with internal thread on the round platform, during stretch-draw, plants the stretch-draw tube 10 of setted structure therewith and should be with external screw thread (referring to Fig. 2).

Claims

1; a kind of vertical steel strand pre-stressed anchored system; comprise fixed end; the stretch-draw end; presstressed reinforcing steel; be connected with bellows between fixed end and the stretch-draw end; form airtight protection duct; the spiral bar that booster action has been arranged under the anchor plate of two ends; it is characterized in that: described presstressed reinforcing steel is steel strand (5); described fixed end is by extruding anchor (1); fixed end anchor slab (2) constitutes; described stretch-draw end is by stretch-draw end anchor plate (6); clamp nut (7); work anchor slab (8); intermediate plate (9) is formed; anchor plate (6) small end is enclosed within the bellows; clamp nut (7) is pressed on the anchor plate (6); columniform work anchor slab (8) is connected and fixed by external screw thread and clamp nut (7); the anchor hole that steel strand (5) one ends of fixed length pass fixed end anchor slab (2) is fixed on fixed end anchor slab place by extruding anchor (1) extruding, and the other end of steel strand (5) is anchored on the work anchor slab (8) of stretch-draw end by intermediate plate (9).

2, vertical steel strand pre-stressed anchored system according to claim 1 is characterized in that: a truncated cone-shaped groove is arranged on the described work anchor slab (8), internal thread is arranged on the round platform.