Prestressed concrete composite box beam reinforcement structure and construction method

Abstract

The present invention relates to a prestressed concrete composite box girder reinforcement structure and construction method, including the following steps: step 1. measurement and setting out; step 2. construction of newly added anchoring tooth plates and newly added transverse diaphragms; step 3. opening holes in the original transverse diaphragms; step 4. construction of bogies and limit shock absorbers; step 5. punching holes in external prestressed tendons; step 6. tensioning and anchoring of external prestressed tendons. The beneficial effects of the present invention are as follows: the bogie proposed in the present invention, the eccentric ring of the constraining guide sleeve can rotate relative to the angle steel, the axis position of the guide sleeve can be fine-tuned, and the axis positioning accuracy of the external prestressed tendons is improved; the limit shock absorber proposed in the present invention, the limit ring is sleeved on the external prestressed tendons, and a limit spring is arranged between the limit ring and the angle steel, which can provide a better shock-absorbing and isolating effect; the concrete box girders of the present invention are provided with newly added transverse diaphragms, which can significantly improve the stability of the concrete box girders and improve the reinforcement effect.

Description

Technical Field

[0001] The invention relates to bridge reinforcement and reconstruction construction, and in particular to a prestressed concrete composite box girder reinforcement system. Background Art

[0002] Due to the rapid growth of traffic flow, some bridges have been overloaded. In order to ensure driving safety, bridges need to be reinforced and reconstructed. The existing reinforcement and reconstruction construction technology mainly involves pasting carbon fiber cloth on the surface of the bridge or setting external prestressed tendons to improve the durability of the bridge. In order to anchor the external prestressed tendons, an anchoring structure needs to be set at the beam end. The traditional anchoring structure mainly installs a steel structure anchor box at the beam end or applies a cast-in-place concrete anchor tooth plate. The steel structure anchor box is a prefabricated component, which can reduce the workload on site, but it is necessary to drill a large number of bolt holes in the beam body, which has a certain impact on the strength of the beam body and is easy to drill off the existing prestressed tendons in the beam body. Although the cast-in-place concrete anchor tooth plate has a good bonding effect with the surface of the beam body, it is difficult to pour concrete and the amount of formwork under the beam is large. In order to improve the force effect, the newly added prestressed tendons are usually bent at the beam end, so it is necessary to set a prestressed tendon bogie outside the beam body. The traditional prestressed tendon bogie is difficult to install and position, resulting in the deviation of the axis of the prestressed tendon from the design axis after the construction is completed, reducing the reinforcement effect. In addition, in order to prevent the external prestressed tendons from shaking and relaxing under the action of their own weight and reduce the additional stress in the prestressed tendons, it is necessary to set a shock-absorbing device for the external prestressed tendons. However, the traditional shock-absorbing device mainly sets a rigid support rod outside the beam body to fix the prestressed tendons and the rigid support rod, which has a poor shock-absorbing effect. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a prestressed concrete composite box girder reinforcement structure and a construction method.

[0004] The construction method of the prestressed concrete composite box beam reinforcement structure comprises the following construction steps:

[0005] Step 1. Measurement and staking: Measure on the concrete box girder, locate and stake out the positions of the newly added anchor tooth plates and newly added cross beams, and mark the positions of the prestressed tendons in the concrete box girder;

[0006] Step 2. Construction of new anchor tooth plates and new transverse beams: roughen the contact surface between the concrete box beam and the new anchor tooth plates and the new transverse beams, and construct shear grooves on the surface of the concrete box beams; then implant anti-collapse steel bars and shear nails on the surface of the concrete box beams, place pre-buried guide tubes and pre-buried casings according to the design axis, and cast the new anchor tooth plates and new transverse beams;

[0007] Step 3. Opening holes in the original transverse beam: according to the axis position of the external prestressed tendons, a hole is opened on the original transverse beam, and a stiffening sleeve is set at the hole;

[0008] Step 4. Construction of bogie and limit shock absorber: According to the design axis of the external prestressed tendon, install the bogie at the bend of the external prestressed tendon, and use bolts to fix the bogie on the concrete box girder; pass the guide sleeve through the eccentric ring, and adjust the angle of the eccentric ring so that the axis of the guide sleeve is consistent with the axis of the external prestressed tendon; use bolts to fix the limit shock absorber on the concrete box girder, and make the axis of the limit ring consistent with the axis of the external prestressed tendon;

[0009] Step 5. Punching of external prestressed tendons: The external prestressed tendons are respectively passed through the limiting ring of the limiting shock absorber, the guide sleeve of the bogie, the newly added cross beam and the holes on the original cross beam, and the two ends of the external prestressed tendons are passed through the embedded conduits in the newly added anchoring tooth plate;

[0010] Step 6. Tensioning and anchoring of external prestressed tendons: tension the two ends of the external prestressed tendons. After the external prestressed tendons are tensioned into place, use anchors to anchor them on the newly added anchor tooth plates.

[0011] Preferably: in step 4, the bogie is mainly composed of a base plate, an angle steel, an eccentric ring and a guide sleeve, the eccentric ring is located in a circular hole on the angle steel, and the guide sleeve passes through the eccentric ring; the limit shock absorber is mainly composed of a base plate, an angle steel, a limit ring and a limit spring, the limit ring is located in the circular hole on the angle steel, and a limit spring is provided between the limit ring and the angle steel.

[0012] Preferably, the limit ring on the shock-absorbing limiter moves relative to the angle steel; and the eccentric ring rotates relative to the angle steel.

[0013] This prestressed concrete composite box girder reinforcement structure is constructed according to the above-mentioned construction method.

[0014] The beneficial effects of the present invention are:

[0015] 1. In the bogie proposed by the present invention, the eccentric ring constraining the guide sleeve can rotate relative to the angle steel, so as to fine-tune the axis position of the guide sleeve and improve the axis positioning accuracy of the external prestressed tendons.

[0016] 2. The limit shock absorber proposed in the present invention is composed of a limit ring sleeved on the external prestressed tendon, and a limit spring is arranged between the limit ring and the angle steel, which can provide a better shock absorption and isolation effect.

[0017] 3. New transverse beams are provided between the concrete box beams of the present invention, which can significantly improve the stability of the concrete box beams and enhance the reinforcement effect.

[0018] 4. The external prestressed tendons of the present invention are anchored on the newly added anchoring tooth plate, and the anchoring effect is good; the original transverse diaphragm is provided with a hole for the external prestressed tendons to pass through, thereby avoiding the conflict between the external prestressed tendons and the original transverse diaphragm. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the elevation drawing of the design of external prestressed reinforcement of composite box girder;

[0020] Figure 2 It is the design plan of external prestressed reinforcement of composite box girder;

[0021] Figure 3 It is the design elevation drawing of the external prestressed reinforcement of the composite box girder (end);

[0022] Figure 4 It is the design plan of the external prestressed reinforcement of the composite box girder (end);

[0023] Figure 5 It is a schematic diagram of the structure of the newly added anchoring tooth plate;

[0024] Figure 6 It is a schematic diagram of the installation plane of the prestressed tendon bogie;

[0025] Figure 7 It is a schematic diagram of the installation structure of the prestressed tendon bogie;

[0026] Figure 8 This is the large-scale drawing of the prestressed tendon bogie installation;

[0027] Fig. 9 This is the installation drawing of the prestressed tendon limit shock absorber;

[0028] Fig.10 It is a schematic diagram of the newly added diaphragm structure;

[0029] Fig.11 Newly added cross-section diagram of the diaphragm ( Fig.10 Middle AA section);

[0030] Fig.12 This is a schematic diagram of the original cross beam opening structure;

[0031] Fig.13 This is the original cross-section diagram of the diaphragm ( Fig.12 mid-BB section);

[0032] Fig.14 It is the construction process flow chart of the prestressed concrete composite box girder reinforcement system.

[0033] Explanation of the accompanying drawings: 1-concrete box girder, 11-top plate, 12-prestressed tendons in the beam, 13-channel, 14-original cross beam, 15-reinforcing sleeve, 2-external prestressed tendons, 21-anchor, 3-newly added cross beam, 31-embedded sleeve, 32-shear nail, 4-newly added anchor tooth plate, 41-shear groove, 42-embedded guide tube, 43-anti-collapse steel bar, 51-bogie, 52-limit shock absorber, 53-bottom plate, 54-angle steel, 55-bolt, 56-eccentric ring, 57-guide sleeve, 58-limit ring, 59-limit spring. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principles of the present invention, several improvements and modifications may be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0035] As an embodiment, the construction method of the prestressed concrete composite box beam reinforcement structure has the following construction steps: Fig.14 The specific construction steps are as follows:

[0036] Step 1. Measurement and setting out: measurement is performed on the concrete box girder 1, and the positions of the newly added anchoring tooth plates 4 and the newly added cross beams 3 are located and set out, and the positions of the prestressed tendons 12 in the beam are marked on the concrete box girder 1 to avoid damage to the prestressed tendons 12 in the beam during subsequent construction;

[0037] Step 2. Construction of newly added anchoring tooth plates 4 and newly added transverse diaphragms 3: roughen the contact surfaces between the concrete box girder 1 and the newly added anchoring tooth plates 4 and the newly added transverse diaphragms 3, and construct shear grooves 41 on the surface of the concrete box girder 1; then implant anti-collapse steel bars 43 and shear nails 32 on the surface of the concrete box girder 1, and place pre-buried guide tubes 42 and pre-buried sleeves 31 according to the designed axis, and cast the newly added anchoring tooth plates 4 and the newly added transverse diaphragms 3;

[0038] Step 3. Opening holes in the original transverse beam 14: opening holes 13 in the original transverse beam 14 according to the axis position of the external prestressed tendons 2, and setting stiffening sleeves 15 at the holes 13;

[0039] Step 4. Construction of the bogie 51 and the limit shock absorber 52: According to the design axis of the external prestressed tendon 2, the bogie 51 is installed at the bend of the external prestressed tendon 2, and the bogie 51 is fixed to the concrete box girder 1 using the bolt 55; the guide sleeve 57 is passed through the eccentric ring 56, and the angle of the eccentric ring 56 is adjusted so that the axis of the guide sleeve 57 is consistent with the axis of the external prestressed tendon 2; the limit shock absorber 52 is installed and fixed to the concrete box girder 1 using the bolt 55, and the axis of the limit ring 58 is consistent with the axis of the external prestressed tendon 2;

[0040] Step 5. Punching the external prestressed tendons 2: The external prestressed tendons 2 are respectively passed through the limiting ring 58 of the limiting shock absorber 52, the guide sleeve 57 of the bogie 51, the newly added transverse beam 3 and the hole 13 on the original transverse beam 14, and the two ends of the external prestressed tendons 2 are passed out from the embedded guide tube 42 in the newly added anchoring tooth plate 4;

[0041] Step 6. Tensioning and anchoring of the external prestressed tendons 2: tensioning is performed on both ends of the external prestressed tendons 2. After the external prestressed tendons 2 are tensioned into place, they are anchored on the newly added anchoring tooth plates 4 using anchors 21.

[0042] The prestressed concrete composite box girder reinforcement structure obtained by the above construction method is as shown in the attached Figure 1 , Attachment Figure 2 As shown, it includes an external prestressed tendon 2, a newly added transverse beam 3, a newly added anchoring tooth plate 4, a bogie 51, a limit shock absorber 52, etc.; the newly added anchoring tooth plate 4 is arranged at both ends of the concrete box beam 1, and a pre-buried conduit 42 is arranged in the newly added anchoring tooth plate 4, as shown in the attached Figure 3 As shown; the newly added transverse beam 3 is arranged along the longitudinal direction of the concrete box beam 1, and a pre-buried sleeve 31 is provided in the newly added transverse beam 3; as shown in the attached Figure 6 , Attachment Figure 7 As shown, the bogie 51 is arranged at the bend of the external prestressed tendon 2, and the bogie 51 is composed of a base plate 53, an angle steel 54, an eccentric ring 56 and a guide sleeve 57. The eccentric ring 56 is located in the circular hole on the angle steel 54, and the guide sleeve 57 passes through the eccentric ring; a plurality of limit shock absorbers 52 are arranged along the straight section of the external prestressed tendon 2, and the limit shock absorber 52 is composed of a base plate 53, an angle steel 54, a limit ring 58 and a limit spring 58. The limit ring 58 is located in the circular hole on the angle steel 54, and a limit spring 59 is provided between the limit ring 58 and the angle steel 54; the external prestressed tendon 2 passes through the limit ring 58, the guide sleeve 57, the original transverse beam 14, the newly added transverse beam 3, and the embedded conduit 42, and both ends are anchored on the newly added anchoring tooth plate 4 through the anchor 21.

[0043] As attached Fig.12 , Attachment Fig.13As shown, a hole 13 is provided on the original transverse beam 14 to facilitate the passage of the external prestressed tendons 2 , and a stiffening sleeve 15 is arranged in the hole 13 to ensure the strength of the original transverse beam 14 and prevent the original transverse beam 14 from cracking at the hole 13 .

[0044] As attached Figure 4 , Attachment Figure 5 As shown, a shear groove 41 is provided at the contact point between the concrete box girder 1 and the newly added anchoring tooth plate 4, which is formed by chiseling away part of the concrete on the surface of the concrete box girder 1; an anti-collapse steel bar 43 is provided between the newly added anchoring tooth plate 4 and the concrete box girder 1, one end of the anti-collapse steel bar 43 is anchored in the concrete box girder 1, and the other end of the anti-collapse steel bar 43 is cast in the newly added anchoring tooth plate 4; the bite force between the newly added anchoring tooth plate 4 and the concrete box girder 1 is increased by providing the shear groove 41 and the anti-collapse steel bar 43, thereby ensuring the reliability of the structure. Fig.10 , Attachment Fig.11 As shown, a shear nail 32 is provided between the newly added transverse diaphragm 3 and the concrete box beam 1, one end of the shear nail 32 is anchored in the concrete box beam 1, and the other end of the shear nail 41 is cast in the newly added transverse diaphragm 3, so as to improve the bonding force between the newly added transverse diaphragm 3 and the concrete box beam 1 and improve the reliability of the newly added transverse diaphragm 3. A top plate 11 is provided on the top of the concrete box beam 1.

[0045] The angle steel 54 of the bogie 51 and the damping stopper 52 are welded to the bottom plate 53, and the bogie 51 and the damping stopper 52 are fixed to the concrete box beam 1 using bolts 55. Fig. 9 As shown, the limit ring 58 on the shock-absorbing limiter 52 can move relative to the angle steel 54 to prevent the vibration of the beam body from being transmitted to the external prestressed tendons 2, thereby ensuring the reliability of the external prestressed tendons 2. Figure 8 As shown, the eccentric ring 56 can rotate relative to the angle steel 54. By rotating the eccentric ring 56, the axial position of the guide sleeve 57 is adjusted so that the axial position of the external prestressed tendon 2 meets the design requirements.

Claims

1. A construction method for a prestressed concrete composite box beam reinforcement structure, characterized in that: The construction steps include: Step 1. Measurement and staking: Measure on the concrete box girder, locate and stake out the positions of the newly added anchoring tooth plates and the newly added cross beams, and mark the positions of the prestressed tendons in the concrete box girder; Step 2. Construction of new anchor tooth plates and new transverse beams: roughen the contact surface between the concrete box beam and the new anchor tooth plates and the new transverse beams, and construct shear grooves on the surface of the concrete box beams; then implant anti-collapse steel bars and shear nails on the surface of the concrete box beams, place pre-buried guide tubes and pre-buried sleeves according to the design axis, and cast the new anchor tooth plates and new transverse beams; Step 3. Open holes in the original transverse beam: according to the axis position of the external prestressed tendons, open holes in the original transverse beam and set stiffening sleeves at the holes; Step 4. Construction of bogie and limited shock absorber: According to the design axis of the external prestressed tendons, install the bogie at the bend of the external prestressed tendons, and use bolts to fix the bogie on the concrete box girder; pass the guide sleeve through the eccentric ring, and adjust the angle of the eccentric ring so that the axis of the guide sleeve is consistent with the axis of the external prestressed tendons; Use bolts to fix the limit shock absorber on the concrete box beam, and make the axis of the limit ring consistent with the axis of the external prestressed tendons; Step 5. Punch holes for external prestressed tendons: The external prestressed tendons are respectively passed through the limit ring of the limit shock absorber, the guide sleeve of the bogie, the newly added cross beam and the holes on the original cross beam, and the two ends of the external prestressed tendons are passed out from the embedded conduits in the newly added anchor tooth plate; Step 6. Tensioning and anchoring of external prestressed tendons: tension the two ends of the external prestressed tendons. After the external prestressed tendons are tensioned in place, they are anchored on the newly added anchoring tooth plates using anchors; In step 4, the bogie is mainly composed of a base plate, an angle steel, an eccentric ring and a guide sleeve, the eccentric ring is located in a circular hole on the angle steel, and the guide sleeve passes through the eccentric ring; the limit shock absorber is mainly composed of a base plate, an angle steel, a limit ring and a limit spring, the limit ring is located in a circular hole on the angle steel, and a limit spring is provided between the limit ring and the angle steel; The limiting ring on the shock-absorbing limiter moves relative to the angle steel; and the eccentric ring rotates relative to the angle steel.

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