Bridge box girder structure and construction method thereof

Abstract

The invention discloses a bridge box girder structure which comprises a plurality of box girders connected in sequence, a support structure used for supporting the box girders on piers, an anchoring device used for prestress tensioning of the box girders and a water seepage prevention device arranged on the box girders. The stay cable is fixedly connected with one end of a shockproof pull rope, and the other end of the shockproof pull rope is fixed on the box girder; the water seepage prevention device is provided with a first through hole allowing a beam end embedded pipe of a stay cable to penetrate through and a second through hole allowing a quakeproof pull rope to penetrate through. A first annular groove is formed in the first through hole, and an annular expansion water stop strip is arranged in the first annular groove; a second annular groove is formed in the second through hole, and an annular expansion water stop strip is also arranged in the second annular groove. By arranging the water seepage prevention device, liquid water is prevented from flowing into the gap along the stay cable and the shockproof pull rope through the expansion water stop strips in the first through hole and the second through hole in the water seepage prevention device, and then the situation that the anchoring position of the stay cable, the fixing position of the shockproof pull rope and other positions which are not easy to overhaul are rusted due to the liquid water is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a bridge box girder structure and a construction method thereof. Background Art

[0002] The low-tower cable-stayed bridge is a bridge structure that combines the characteristics of continuous beams and cable-stayed bridges. Its main features are low bridge towers, large main beam stiffness, and concentrated cable stays. In this bridge system, the main beam is the main load-bearing component with significant stiffness, while the cable stays play the role of enhancing the main beam stiffness and adjusting the force distribution. Compared with continuous beam bridges, low-tower cable-stayed bridges show novelty in structural design, large span capacity, simplicity in construction, and economic benefits; compared with traditional cable-stayed bridges, it has obvious advantages in construction convenience, material saving, and main beam stiffness. However, this structure also has some problems. Since the specific heat capacity of the cable stay material is lower than that of water, the cable body cools down faster during the cooling process, making it easy for water vapor in the air to condense into water droplets on the surface of the cable body and flow down along the cable body. In addition, rainwater also tends to flow down along the inclined cable body. This liquid water will eventually flow to the anchor end of the cable body and the connection between the damper and the bridge box girder, causing corrosion of the prestressed tendons and dampers in the cable body, which will in turn have an adverse effect on the service life of the cable. Summary of the invention

[0003] The present invention provides a bridge box girder structure and a construction method thereof to solve the above technical problems.

[0004] In order to achieve the above object, the technical solution of the present invention is:

[0005] A bridge box girder structure comprises: a plurality of box girders connected in sequence, a support structure for supporting the box girders on a pier, an anchoring device for prestressing the box girders and an anti-seepage device arranged on the box girder; one end of an anti-seismic cable is fixedly connected to the inclined cable, and the other end of the anti-seismic cable is fixed to the box girder; the anti-seepage device is provided with a first through hole for passing the embedded pipe at the beam end of the inclined cable and a second through hole for passing the anti-seismic cable; a first annular groove is provided in the first through hole, and an annular expansion water stop strip is provided in the first annular groove; a second annular groove is provided in the second through hole, and an annular expansion water stop strip is also provided in the second annular groove.

[0006] Preferably, the anti-water seepage device includes: a first mounting block, a second mounting block, a third mounting block and a locking structure; the second mounting block and the third mounting block are located on one side of the first mounting block, the second mounting block and the third mounting block are arranged opposite to each other, the first mounting block, the second mounting block and the third mounting block abut against each other, and the first mounting block, the second mounting block and the third mounting block all abut against the upper surface of the box girder; the first through hole is divided into three parts by the first mounting block, the second mounting block and the third mounting block, and the second through hole is divided into two parts by the second mounting block and the third mounting block; the locking structure is used to fix the first mounting block, the second mounting block and the third mounting block as a whole.

[0007] Preferably, the locking structure includes: a first bolt, a second bolt, a third bolt and a fourth bolt; the first bolt is used to connect the first mounting block and the second mounting block, the second bolt is used to connect the first mounting block and the third mounting block, the third bolt is used to connect the second mounting block and the third mounting block from a side of the second mounting block and the third mounting block away from the box beam, and the fourth bolt is used to connect the second mounting block and the third mounting block from a side of the second mounting block and the third mounting block away from the first mounting block.

[0008] Preferably, a clearance groove is provided on the side of the anti-seepage device facing the box beam, the clearance groove is connected to the second through hole, and the clearance groove is divided into two parts by the second mounting block and the third mounting block.

[0009] Preferably, the support structure includes: a support, a friction layer and at least two anchor bolts; a plurality of first blind holes are opened on the pier, the lower ends of the anchor bolts are inserted into the first blind holes and fixedly connected, and the anchor bolts correspond to the first blind holes one by one; a plurality of second blind holes are opened on the lower surface of the support, the upper ends of the anchor bolts are inserted into the second blind holes and leave gaps with the side walls of the second blind holes, and the anchor bolts correspond to the second blind holes one by one; the friction layer is fixed on the upper surface of the support, and the friction layer is used to increase the friction force in contact with the box girder.

[0010] Preferably, the friction layer is made of friction material.

[0011] Preferably, the anchoring device comprises: a sheath, a restraining ring and a bellows connected in sequence, a connector, a clip and an extrusion anchor are arranged in the sheath, the connector abuts against the inner end surface of the sheath away from the bellows; one end of the prestressed tendons of the box girder of the first section of the bridge passes through the sheath and then into the connector and is connected and fixed with the clip, one end of the prestressed tendons of the box girder of the second section of the bridge passes through the bellows, the restraining ring and the bellows in sequence and then passes through the connector and is connected and fixed with the extrusion anchor; a waterproof cloth is arranged in the restraining ring, and the waterproof cloth is twisted into a ball under the tensioning action of the prestressed tendons of the box girder of the second section of the bridge to block the inner hole of the restraining ring.

[0012] Preferably, a support plate is provided outside the jacket of the jacket, the support plate is perpendicular to the center line of the jacket and the two are fixedly connected; an elastic member is fixedly provided on the side of the support plate away from the corrugated tube, and one end of the elastic member away from the support plate abuts against the first section box girder of the bridge; when the outer end face of the jacket away from the corrugated tube abuts against the first section box girder of the bridge, the elastic force generated by the elastic member is less than the limit pressure of the pressure-type failure of the first section box girder.

[0013] Preferably, a protective cushion layer is fixedly provided on the outer end surface of the sheath away from the corrugated pipe, and the protective cushion layer is used for buffering after the outer end surface of the sheath away from the corrugated pipe abuts against the first section box girder of the bridge.

[0014] A construction method for a bridge box girder structure comprises the following steps:

[0015] S1. Build supports on the bridge piers;

[0016] S2. Hang the box girder on the supports of two adjacent piers;

[0017] S3. Install anchoring devices on the box beam;

[0018] S4, prestressing the prestressed tendons in the box girder by means of jacks and anchoring devices;

[0019] S5. Install the inclined cables and anti-vibration ropes on the box girder;

[0020] S6. Install anti-water seepage device on the box girder.

[0021] Beneficial effects:

[0022] First, a bridge box girder structure disclosed in the present application is provided with an anti-water seepage device, and the expansion water stop strips in the first through hole and the second through hole on the anti-water seepage device prevent liquid water from flowing into the gap along the inclined cables and the anti-seismic ropes, thereby preventing the liquid water from causing rust at the anchoring positions of the inclined cables and the fixed positions of the anti-seismic ropes, which are not easy to inspect.

[0023] Second, a construction method for a bridge box girder structure disclosed in the present application can achieve reliable and rapid construction of the above-mentioned bridge box girder structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 It is a structural schematic diagram of a bridge box girder structure disclosed in the present invention;

[0026] Figure 2 It is a structural schematic diagram of a bridge box girder structure inclined cable disclosed by the present invention;

[0027] Figure 3 for Figure 2 Sectional view of middle Ⅰ;

[0028] Figure 4 It is a structural schematic diagram of a water seepage prevention device for a bridge box girder structure disclosed by the present invention;

[0029] Figure 5 A top view of a water seepage prevention device for a bridge box girder structure disclosed in the present invention;

[0030] Figure 6 It is a structural schematic diagram of a bridge box girder structure support structure disclosed in the present invention;

[0031] Figure 7 A cross-sectional view of a bridge box girder structure support structure disclosed in the present invention;

[0032] Figure 8 It is a structural schematic diagram of a bridge box girder structure support and a friction layer assembly disclosed in the present invention;

[0033] Fig. 9 It is a structural schematic diagram of a detachable prefabricated steel formwork for a bridge box girder structure disclosed in the present invention;

[0034] Fig.10 A schematic diagram of the installation position of an anchoring device for a bridge box girder structure disclosed in the present invention;

[0035] Fig.11 It is a structural schematic diagram of an anchoring device of a bridge box girder structure and a construction method thereof disclosed in the present invention;

[0036] Fig.12 The present invention discloses a schematic diagram of an assembly of a sheath, a restraining ring, a waterproof cloth, a supporting plate, an elastic member and a protective cushion layer of an anchoring device for a bridge box girder structure.

[0037] 1. Box girder; 11. Prestressed tendons;

[0038] 21. Support; 22. Friction layer; 23. Anchor bolt; 24. Plastic cement; 251. Formwork; 252. Leakage-proof strip; 253. Protective support plate; 254. Support rod; 255. Support block; 256. Support friction layer;

[0039] 311, sheath; 312, restraint ring; 313, bellows; 321, connector; 322, clip; 323, extrusion anchor; 33, waterproof cloth; 34, support plate; 35, elastic member; 36, protective cushion;

[0040] 41. Tensioning nut; 42. Cable jack; 43. Tensioning rod; 44. Connecting sleeve; 45. Support foot; 451. Support foot protective shell; 452. Support foot end plate; 46. Beam end embedded pipe; 461. Embedded pipe pressure plate; 47. Cable body; 48. Buffer support seat; 49. Cable body waterproof cover; 410. Waterproof cover;

[0041] 51, first through hole; 52, second through hole; 53, first mounting block; 54, second mounting block; 55, third mounting block; 561, first bolt; 562, second bolt; 563, third bolt; 564, fourth bolt; 57, clearance groove;

[0042] 7. Bridge piers; 8. Shockproof ropes. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Example 1

[0045] A bridge box girder structure and construction method thereof, combined with Figure 1 - Fig.12 As shown, it includes: a plurality of box girders 1 connected in sequence, a support structure for supporting the box girder 1 on the pier 7, an anchoring device for prestressing the box girder 1 and an anti-seepage device arranged on the box girder 1; one end of the anti-seismic rope 8 is fixedly connected to the inclined cable 4, and the other end of the anti-seismic rope 8 is fixed to the box girder 1; the anti-seepage device is provided with a first through hole 51 for the beam end embedded pipe 46 of the inclined cable 4 to pass through, and a second through hole 52 for the anti-seismic rope 8 to pass through; a first annular groove is provided in the first through hole 51, and an annular expansion water stop strip is provided in the first annular groove; a second annular groove is provided in the second through hole 52, and an annular expansion water stop strip is also provided in the second annular groove. The expansion water stop strip in the first through hole 51 abuts against the inner wall of the first annular groove and fits tightly against the outer periphery of the beam end embedded pipe 46. When liquid water flows down along the beam end embedded pipe 46, the expansion water stop strip absorbs water and expands to achieve sealing, preventing the liquid water from continuing to flow downward to the anchoring position of the inclined cable 4. The expansion water stop strip in the second through hole 52 abuts against the inner wall of the second annular groove and fits tightly against the outer periphery of the shockproof cable 8. When liquid water flows down along the shockproof cable 8, the expansion water stop strip absorbs water and expands to achieve sealing, preventing the liquid water from continuing to flow downward to the fixed position of the shockproof cable 8.

[0046] Specifically, the anchoring device includes: a tensioning nut 41, a cable jack 42, a tensioning rod 43, a connecting sleeve 44, a support leg 45, a beam end embedded pipe 46 and a cable body 47. A buffer support seat 48 is also provided between the box beam 1 and the support leg 45. One side of the buffer support seat 48 abuts against the box beam 1 and the other side abuts against the support leg 45. The buffer support seat 48 is made of elastic material; the support leg 45 includes a cylindrical support leg protective shell 451 and an annular support leg end plate 452, and the support leg end plate 452 is fixed to the support leg. The foot protection shell 451 has an open end; the buffer support seat 48 and the foot support end plate 452 are sleeved on the beam end embedded pipe 46, and the inner diameters of the buffer support seat 48 and the foot support end plate 452 are consistent with the outer diameter of the beam end embedded pipe 46; the end of the beam end embedded pipe 46 is inserted into the support foot 45 and fixed with an annular embedded pipe pressing plate 461, which abuts against the surface of the support foot end plate 452 away from the buffer support seat 48, and the outer diameter of the embedded pipe pressing plate 461 is consistent with the inner diameter of the foot protection shell 451. The embedded pipe pressing plate 461 presses the support foot end plate 452, and the support foot end plate 452 presses the buffer support seat 48, and the buffer support seat 48 abuts against the box beam 1, so that the force borne by the support foot 45 and the beam end embedded pipe 46 is transmitted to the box beam 1 through the buffer support seat 48, and the buffering effect of the buffer support seat 48 prevents the support foot 45 from directly contacting the box beam 1 and crushing the box beam 1. In addition, the inner diameters of the buffer support seat 48 and the support foot end plate 452 are consistent with the outer diameter of the beam end embedded pipe 46, and the outer diameter of the embedded pipe pressing plate 461 is consistent with the inner diameter of the support foot protective shell 451, which is conducive to the positioning of the buffer support seat 48 and the support foot end plate 452, and avoids the buffer support seat 48 and the support foot 45 from shifting and affecting the buffering effect of the buffer support seat 48. At the same time, the small size of the buffer support seat 48 makes it easy to manufacture, so that it also has the advantage of low cost.

[0047] Preferably, the buffer support seat 48 is made of high-damping rubber material. The high-damping rubber material has very high damping characteristics, can absorb and dissipate mechanical energy, and reduce the transmission of vibration and impact.

[0048] Preferably, the buffer support seat 48 is truncated cone-shaped, the upper bottom surface diameter of the buffer support seat 48 is consistent with the outer diameter of the support foot end plate 452, and the lower bottom surface diameter of the buffer support seat 48 matches the working surface of the box beam 1. The truncated cone shape can increase the contact area between the buffer support seat 48 and the box beam 1 and reduce pressure concentration.

[0049] Preferably, the end of the beam end embedded pipe 46 away from the support leg 45 passes through the box beam 1 and is covered with a cable body waterproof cover 49, and the end of the cable body waterproof cover 49 away from the beam end embedded pipe 46 is covered with a waterproof cover 410; one end of the cable body 47 is connected to the connecting sleeve 44, and the other end passes through the beam end embedded pipe 46, the cable body waterproof cover 49 and the waterproof cover 410 in sequence. The beam end embedded pipe 46, the cable body waterproof cover 49 and the waterproof cover 410 form a protective structure to prevent rainwater and water vapor from directly contacting the cable body 47.

[0050] Preferably, one end of the anti-shock rope 8 passes through the waterproof cover 410 and is fixedly connected to the rope body 47, and the other end of the anti-shock rope 8 is fixed on the box beam 1. The anti-shock rope 8 prevents the rope body 47 from oscillating.

[0051] Specifically, a sensor is installed on the anti-vibration rope 8, and a signal line of the sensor is connected to the monitoring equipment. The sensor detects its own height and thus indirectly detects the operating status of the rope body 47.

[0052] Specifically, a plurality of anti-vibration cables 8 are provided, the upper ends of which are fixedly connected to the cable body 47 by bolts and buckles, and the lower ends of which are fixedly connected to the box beam 1 by anchor bolts. The expansion water stop strip in the second annular groove can prevent liquid water from flowing into the gap between the anti-vibration cables 8 and the second through hole 52, thereby preventing liquid water from flowing to the anchor bolts to cause them to rust, thereby preventing the anti-vibration cables 8 from loosening.

[0053] Preferably, the anti-seepage device includes: a first mounting block 53, a second mounting block 54, a third mounting block 55 and a locking structure; the second mounting block 54 and the third mounting block 55 are located on one side of the first mounting block 53, the second mounting block 54 and the third mounting block 55 are arranged opposite to each other, the first mounting block 53, the second mounting block 54 and the third mounting block 55 are abutted against each other in pairs, and the first mounting block 53, the second mounting block 54 and the third mounting block 55 are all abutted against the upper surface of the box girder 1; the first through hole 51 is divided into three parts by the first mounting block 53, the second mounting block 54 and the third mounting block 55, and the second through hole 52 is divided into two parts by the second mounting block 54 and the third mounting block 55; the locking structure is used to fix the first mounting block 53, the second mounting block 54 and the third mounting block 55 as a whole. If the first through hole 51 and the second through hole 52 are formed by merging two mounting blocks as usual, the expansion water stop strip in the first annular groove and the expansion water stop strip in the second annular groove cannot be reliably compressed due to the large difference in diameter between the shockproof rope 8 and the beam end embedded pipe 46. For example: after the expansion water stop strip in the first annular groove is compressed, it tightly surrounds the outer periphery of the beam end embedded pipe 46, but due to the error, part of the expansion water stop strip in the second annular groove cannot be compressed to fit the shockproof rope 8, which will cause water leakage. However, this problem can be solved by assembling three mounting blocks in steps. Specifically, the second mounting block 54 and the third mounting block 55 are first spliced ​​together and then locked. The two parts of the second through hole 52 on the second mounting block 54 and the third mounting block 55 clamp the expansion water stop strip, so that the expansion water stop strip can be tightly attached to the outer periphery of the shockproof rope 8 and the inner wall of the second annular groove. Then, the first mounting block 53 is installed on the combination of the second mounting block 54 and the third mounting block 55 for splicing. By locking the first mounting block 53, the three parts of the first through hole 51 on the first mounting block 53, the second mounting block 54 and the third mounting block 55 press the expansion water stop strip, so that the expansion water stop strip can be tightly attached to the outer periphery of the embedded pipe 46 at the beam end and the inner wall of the first annular groove.

[0054] Specifically, waterproof sealant is applied between the bottom of the first mounting block 53 , the second mounting block 54 , and the third mounting block 55 and the upper surface of the box beam 1 to prevent liquid water from flowing onto the box beam 1 and then seeping in through the gap between the anti-seepage device and the box beam 1 .

[0055] Preferably, the locking structure includes: a first bolt 561, a second bolt 562, a third bolt 563 and a fourth bolt 564; the first bolt 561 is used to connect the first mounting block 53 and the second mounting block 54, the second bolt 562 is used to connect the first mounting block 53 and the third mounting block 55, the third bolt 563 is used to connect the second mounting block 54 and the third mounting block 55 from the side of the second mounting block 54 and the third mounting block 55 away from the box girder 1, and the fourth bolt 564 is used to connect the second mounting block 54 and the third mounting block 55 from the side of the second mounting block 54 and the third mounting block 55 away from the first mounting block 53.

[0056] Specifically, a first ear plate with a through hole is pre-embedded in the side of the first mounting block 53, and a second ear plate with a through hole is pre-embedded in the side of the second mounting block 54, and the first ear plate and the second ear plate are opposite to each other; a third ear plate with a through hole is pre-embedded in the upper surface of the first mounting block 53, and a fourth ear plate with a through hole is pre-embedded in the upper surface of the second mounting block 54, and the third ear plate and the fourth ear plate are opposite to each other; two groups of first bolts 561 pass through the first ear plate and the second ear plate, and the third ear plate and the fourth ear plate respectively, and then are locked to achieve the connection between the first mounting block 53 and the second mounting block 54.

[0057] A fifth ear plate with a through hole is pre-embedded in the other side of the first mounting block 53, and a sixth ear plate with a through hole is pre-embedded in the side of the third mounting block 55, and the fifth ear plate and the sixth ear plate are opposite to each other; a seventh ear plate with a through hole is pre-embedded in the upper surface of the first mounting block 53, and an eighth ear plate with a through hole is pre-embedded in the upper surface of the third mounting block 55, and the seventh ear plate and the eighth ear plate are opposite to each other; two groups of second bolts 562 pass through the fifth ear plate and the sixth ear plate, the seventh ear plate and the eighth ear plate respectively, and then are locked to realize the connection between the first mounting block 53 and the third mounting block 55.

[0058] The second mounting block 54 is pre-buried with a ninth ear plate with a through hole on the side and upper surface away from the first mounting block 53, and the third mounting block 55 is pre-buried with a tenth ear plate with a through hole on the side and upper surface away from the first mounting block 53; the ninth ear plate on the upper surface of the second mounting block 54 is opposite to the tenth ear plate on the upper surface of the third mounting block 55, and the third bolt 563 passes through the corresponding ninth ear plate and the tenth ear plate and is locked to achieve the connection between the second mounting block 54 and the third mounting block 55; the ninth ear plate on the side of the second mounting block 54 away from the first mounting block 53 is opposite to the tenth ear plate on the side of the third mounting block 55 away from the first mounting block 53, and the fourth bolt 564 passes through the corresponding ninth ear plate and the tenth ear plate and is locked to achieve the connection between the second mounting block 54 and the third mounting block 55; the third bolt 563 and the fourth bolt 564 cooperate to achieve a reliable connection between the second mounting block 54 and the third mounting block 55.

[0059] Preferably, a clearance groove 57 is provided on one side of the anti-seepage device facing the box beam 1, the clearance groove 57 is connected to the second through hole 52, and the clearance groove 57 is divided into two parts by the second mounting block 54 and the third mounting block 55. The clearance groove 57 is used to accommodate the anchor bolt at the lower end of the anti-vibration rope 8.

[0060] Preferably, the support structure includes: a support 21, a friction layer 22 and at least two anchor bolts 23; a plurality of first blind holes are provided on the pier 7, the lower ends of the anchor bolts 23 are inserted into the first blind holes and fixedly connected, and the anchor bolts 23 correspond to the first blind holes one by one; a plurality of second blind holes are provided on the lower surface of the support 21, the upper ends of the anchor bolts 23 are inserted into the second blind holes and a gap is left between the anchor bolts 23 and the side walls of the second blind holes, and the anchor bolts 23 correspond to the second blind holes one by one; the friction layer 22 is fixed on the upper surface of the support 21, and the friction layer 22 is used to increase the friction force in contact with the box girder 1. The support 21 is installed by arranging the anchor bolts 23, and the friction force in contact with the box girder 1 is increased by arranging the friction layer 22 on the support 21, so as to enhance the adaptability to stress changes during the operation of the bridge and the adaptability to deformation of the box girder 1 and the pier 7 of the bridge, ensure that the support 21 reliably supports the box girder 1 without relative sliding, and ensure the reliable connection between the upper structure and the lower structure of the bridge.

[0061] Preferably, the upper surface of the friction layer 22 is wavy and / or serrated to increase the friction coefficient of the friction layer 22 .

[0062] Preferably, the friction layer 22 is made of friction material, which can significantly increase the friction force between the friction layer 22 and the box beam 1 .

[0063] Preferably, the friction layer 22 is bonded and fixed to the support 21 .

[0064] Preferably, plastic cement 24 is filled between the lower end of the anchor bolt 23 and the first blind hole, and between the upper surface of the pier 7 and the lower surface of the support 21 , and the plastic cement 24 fixes the lower end of the anchor bolt 23 to the first blind hole.

[0065] Specifically, when pouring the plastic cement 24, ensure that it does not enter the gap between the upper end of the anchor bolt 23 and the side wall of the second blind hole. Since the volume difference between the support 21 and the pier 7 is large, the expansion of the pier 7 and the anchor bolt 23 after the temperature rises is easy to squeeze the support 21, causing the support 21 to be unable to reliably connect the bridge superstructure and the substructure. The gap between the upper end of the anchor bolt 23 and the side wall of the second blind hole can compensate for the expansion of the pier 7 and the anchor bolt 23, preventing damage to the support 21.

[0066] Preferably, the plastic cement 24 is poured through a detachable prefabricated steel form; the detachable prefabricated steel form includes a plurality of templates 251 and protective support components corresponding to the plurality of templates 251, the plurality of templates 251 are sequentially spliced ​​and arranged around the support 21, and the protective support components support the corresponding templates 251. Grouting is performed in the space surrounded by the plurality of templates 251, and the plastic cement 24 gradually covers the upper surface of the pier 7 therein; then the plastic cement 24 gradually flows between the first blind hole and the lower end of the anchor bolt 23, and between the lower surface of the support 21 and the upper surface of the pier 7. After the plastic cement 24 is solidified, the anchor bolt 23 and the pier 7 are fixed, and the support 21 and the pier 7 are fixed.

[0067] Preferably, a leak-proof strip 252 is provided between the template 251 and the pier 7 to prevent the slurry from flowing out.

[0068] Preferably, the protective support assembly includes: a protective support plate 253, a support rod 254, a support block 255 and a support friction layer 256; the protective support plate 253 is arranged on the upper surface of the pier 7 and is located on the side of the template 251 away from the support 21, and the protective support plate 253 abuts the template 251; the support block 255 is arranged on the upper surface of the pier 7 and is located on the side of the protective support plate 253 away from the support 21, the support friction layer 256 is located between the support block 255 and the pier 7, and the support friction layer 256 is fixedly connected to the support block 255; one end of the support rod 254 is fixedly connected to the protective support plate 253, and the other end is fixedly connected to the support block 255.

[0069] Preferably, the anchoring device includes: a sheath 311, a restraining ring 312 and a bellows 313 connected in sequence, a connector 321, a clip 322 and an extrusion anchor 323 are arranged in the sheath 311, and the connector 321 abuts against the inner end surface of the sheath 311 away from the bellows 313; one end of the prestressed tendons of the box girder 1 of the first section of the bridge passes through the sheath 311 and then passes into the connector 321 and is connected and fixed with the clip 322, and one end of the prestressed tendons of the box girder 1 of the second section of the bridge passes through the bellows 313, the restraining ring 312 and the bellows 313 in sequence and then passes through the connector 321 and is connected and fixed with the extrusion anchor 323; a waterproof cloth 33 is arranged in the restraining ring 312, and the waterproof cloth 33 is twisted into a ball under the tensioning action of the prestressed tendons of the box girder 1 of the second section of the bridge to block the inner hole of the restraining ring 312. The twisting and stretching during the tensioning process of the prestressed tendon 11 causes the waterproof cloth 33 to twist into a ball, and the waterproof cloth 33 can tightly press against the inner wall of the constraint ring 312 to block the inner hole of the constraint ring 312, preventing water vapor and rainwater from entering through the bellows 313 and causing rust on the prestressed tendon 11, the connector 321, the clip 322 and the extrusion anchor 323, thereby maintaining the quality of the project and extending the service life of the anchoring device.

[0070] Specifically, one end of the restraint ring 312 is sleeved on the sheath 311 and the other end is sleeved on the bellows 313. The restraint ring 312 clamps the sheath 311 and the bellows 313 to connect the sheath 311 and the bellows 313, thereby achieving sealing at the connection between the sheath 311, the restraint ring 312 and the bellows 313.

[0071] Specifically, the middle part of the restraining ring 312 is a conical part, and the small end of the conical part faces the corrugated tube 313. Under the tensioning action of the prestressed tendons 11, the waterproof cloth 33 can plug the small end of the conical part to further enhance the sealing effect.

[0072] Preferably, a support plate 34 is provided on the outer surface of the jacket 311, and the support plate 34 is perpendicular to the center line of the jacket 311 and the two are fixedly connected; an elastic member 35 is fixedly provided on the side of the support plate 34 away from the bellows 313, and the end of the elastic member 35 away from the support plate 34 abuts against the first section box girder 1 of the bridge; when the outer end surface of the jacket 311 away from the bellows 313 abuts against the first section box girder 1 of the bridge, the elastic force generated by the elastic member 35 is less than the limit pressure of the pressure-type failure of the first section box girder 1. When tensioning is required, the support plate 34 is pressed against the action surface of the tensioning tool used for tensioning the prestressed tendons 11, and the jack of the tensioning tool applies tension to the prestressed tendons 11. The anchoring device moves slowly toward the box girder 1, and the elastic deformation of the elastic member 35 is used to achieve buffering, thereby avoiding the box girder 1 from pressure-type failure.

[0073] Preferably, the elastic member 35 includes a plurality of springs, which are evenly distributed around the axis of the support plate 34. One end of the spring is fixedly connected to the support plate 34, and the other end abuts against the box beam 1 of the first section of the bridge. The plurality of springs can increase the contact area with the box beam 1, which is conducive to achieving a better buffering effect. In addition, the manufacturing cost and maintenance cost of using a plurality of springs are lower than that of a single elastic member.

[0074] Preferably, a protective cushion layer 36 is fixedly arranged on the outer end surface of the sheath 311 away from the bellows 313, and the protective cushion layer 36 is used for buffering after the outer end surface of the sheath 311 away from the bellows 313 abuts against the first section box girder 1 of the bridge. When the spring is compressed to a certain extent and the protective cushion layer 36 abuts against the box girder 1, the buffering of the protective cushion layer 36 prevents the spring from being further compressed to generate excessive elastic force and damage the box girder 1.

[0075] Preferably, the protective cushion layer 36 is made of high damping rubber material, and the protective cushion layer 36 is bonded to the end surface of the sheath 311 .

[0076] Preferably, the sheath 311 is made of stainless steel, the support plate 34 is made of stainless steel, the support plate 34 is fixed to the outer periphery of the sheath 311 by welding, and the spring is fixed to the support plate 34 by welding.

[0077] Example 2

[0078] This embodiment provides a construction method for a bridge box girder structure, comprising the following steps:

[0079] S1. Build supports on the bridge piers;

[0080] S11. Make the first blind hole on the bridge pier and the second blind hole on the support;

[0081] S12, after the lower end of the anchor bolt is inserted into the first blind hole, the support is hoisted so that the upper end of the anchor bolt is inserted into the second blind hole;

[0082] S13, applying a friction layer on the upper side of the support;

[0083] S14. Install leak-proof strips and formwork around the support;

[0084] S15, after pasting the support friction layer on the lower surface of the support block, install it on the upper surface of the pier, then erect a protective support plate on the outer side of the leak-proof strip and the formwork for support, then connect the support rod with the protective support plate, and finally adjust the position of the support block and connect the support rod with the support block;

[0085] S2. Hang the box girder on the supports of two adjacent piers;

[0086] S3. Install anchoring devices on the box beam;

[0087] S31, welding and fixing the connector and the support plate to the sheath;

[0088] S32, passing the prestressed tendons of the box girder of the first section through the sheath and the connector and then connecting them to the clip, passing the prestressed tendons of the box girder of the second section through the sheath and the connector and then connecting them to the extrusion anchor;

[0089] S33, placing a waterproof cloth in the restraint ring, passing the prestressed tendons of the box girder of the second section through the restraint ring and the waterproof cloth and then into the corrugated pipe, inserting the corrugated pipe and the sheath from both ends of the restraint ring, and applying pressure to the restraint ring to connect and seal;

[0090] S34, welding the elastic member on the supporting plate;

[0091] S35, bonding a protective cushion layer to the end of the sheath;

[0092] S4, prestressing the prestressed tendons in the box girder by means of jacks and anchoring devices;

[0093] S41, placing the elastic member against the box beam, installing the tensioning tool and placing the support plate against the action surface of the tensioning tool, the jack of the tensioning tool applies tension to the prestressed tendons, the prestressed tendons are stretched and twisted, so that the waterproof cloth is twisted into a ball and plugs the inner hole of the restraint ring;

[0094] S42, after the tensioning is completed, the tensioning tool is removed;

[0095] S5. Install the inclined cables and anti-vibration ropes on the box girder;

[0096] S51, when embedding the pre-embedded pipe at the end of the beam, the support leg and the buffer support seat are set on the pre-embedded pipe at the end of the beam and pressed and fixed on the box beam;

[0097] S52, sequentially install the cable body waterproof cover, waterproof cover, cable body, connecting sleeve, tension rod, inclined cable jack and tension nut;

[0098] S53, tension cable body;

[0099] S6. Install anti-seepage device on the box girder;

[0100] S61, inserting a semi-annular expansion water stop strip into each half of the second annular groove of the second mounting block and the third mounting block, assembling the second mounting block and the third mounting block, and locking them so that the expansion water stop strip presses the surrounding of the anti-vibration rope;

[0101] S62, inserting semi-circular expansion water stop strips into the half first annular groove of the first mounting block and the half first annular groove formed by the second mounting block and the third mounting block, assembling the combination of the first mounting block, the second mounting block and the third mounting block, and locking them so that the expansion water stop strips press against the periphery of the embedded pipe at the beam end;

[0102] S63, apply waterproof sealant on the bottom and around the first mounting block, the second mounting block and the third mounting block.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bridge box girder structure, characterized in that: include: A plurality of box girders (1) connected in sequence, a support structure for supporting the box girders (1) on a pier (7), an anchoring device for prestressing the box girders (1), and an anti-seepage device arranged on the box girders (1); one end of an anti-vibration cable (8) is fixedly connected to a stay cable (4), and the other end of the anti-vibration cable (8) is fixed to the box girder (1); the anti-seepage device is provided with a first through hole (51) for the beam end pre-buried pipe (46) of the stay cable (4) to pass through, and a second through hole (52) for the anti-vibration cable (8) to pass through; a first annular groove is provided in the first through hole (51), and an annular expansion water stop strip is provided in the first annular groove; a second annular groove is provided in the second through hole (52), and an annular expansion water stop strip is also provided in the second annular groove.

2. A bridge box girder structure according to claim 1, characterized in that: The anti-seepage device comprises: a first mounting block (53), a second mounting block (54), a third mounting block (55) and a locking structure; the second mounting block (54) and the third mounting block (55) are located on one side of the first mounting block (53); the second mounting block (54) and the third mounting block (55) are arranged opposite to each other; the first mounting block (53), the second mounting block (54) and the third mounting block (55) abut against each other in pairs; the first mounting block (53), the second mounting block (54) and the third mounting block (55) all abut against the upper surface of the box beam (1); the first through hole (51) is divided into three parts by the first mounting block (53), the second mounting block (54) and the third mounting block (55); the second through hole (52) is divided into two parts by the second mounting block (54) and the third mounting block (55); the locking structure is used to fix the first mounting block (53), the second mounting block (54) and the third mounting block (55) into one body.

3. A bridge box girder structure according to claim 2, characterized in that: The locking structure comprises: a first bolt (561), a second bolt (562), a third bolt (563) and a fourth bolt (564); the first bolt (561) is used to connect the first mounting block (53) and the second mounting block (54); the second bolt (562) is used to connect the first mounting block (53) and the third mounting block (55); the third bolt (563) is used to connect the second mounting block (54) and the third mounting block (55) from a side of the second mounting block (54) and the third mounting block (55) away from the box girder (1); and the fourth bolt (564) is used to connect the second mounting block (54) and the third mounting block (55) from a side of the second mounting block (54) and the third mounting block (55) away from the first mounting block (53).

4. A bridge box girder structure according to claim 3, characterized in that: A clearance groove (57) is provided on one side of the anti-seepage device facing the box beam (1), the clearance groove (57) is connected to the second through hole (52), and the clearance groove (57) is divided into two parts by the second mounting block (54) and the third mounting block (55).

5. The bridge box girder structure according to claim 1, characterized in that: The support structure comprises: a support (21), a friction layer (22) and at least two anchor bolts (23); a plurality of first blind holes are provided on the pier (7), the lower ends of the anchor bolts (23) are inserted into the first blind holes and fixedly connected, and the anchor bolts (23) correspond one-to-one with the first blind holes; a plurality of second blind holes are provided on the lower surface of the support (21), the upper ends of the anchor bolts (23) are inserted into the second blind holes and a gap is left with the side walls of the second blind holes, and the anchor bolts (23) correspond one-to-one with the second blind holes; the friction layer (22) is fixedly arranged on the upper surface of the support (21), and the friction layer (22) is used to increase the friction force in contact with the box girder (1).

6. A bridge box girder structure according to claim 5, characterized in that: The friction layer (22) is made of friction material.

7. The bridge box girder structure according to claim 1, characterized in that: The anchoring device comprises: a sheath (311), a restraining ring (312) and a corrugated pipe (313) connected in sequence; a connector (321), a clamp (322) and an extrusion anchor (323) are arranged in the sheath (311); the connector (321) abuts against the inner end surface of the sheath (311) away from the corrugated pipe (313); one end of the prestressed tendon of the box girder (1) of the first section of the bridge passes through the sheath (311) and then enters the connector (321) and is connected to the clamp ( 322) is connected and fixed, one end of the prestressed tendons of the box girder (1) of the second section of the bridge passes through the corrugated pipe (313), the restraining ring (312) and the corrugated pipe (313) in sequence, and then passes through the connecting body (321) and is connected and fixed to the extrusion anchor (323); a waterproof cloth (33) is provided in the restraining ring (312), and the waterproof cloth (33) is twisted into a ball under the tensioning action of the prestressed tendons of the box girder (1) of the second section of the bridge to block the inner hole of the restraining ring (312).

8. A bridge box girder structure according to claim 7, characterized in that: The outer shell of the sleeve (311) is provided with a support plate (34), and the support plate (34) is perpendicular to the center line of the sleeve (311) and the two are fixedly connected; an elastic member (35) is fixedly provided on the side of the support plate (34) away from the bellows (313), and the end of the elastic member (35) away from the support plate (34) abuts against the first section box girder (1) of the bridge; when the outer end surface of the sleeve (311) away from the bellows (313) abuts against the first section box girder (1) of the bridge, the elastic force generated by the elastic member (35) is less than the limit pressure of the pressure-type failure of the first section box girder (1).

9. A bridge box girder structure according to claim 8, characterized in that: A protective cushion layer (36) is fixedly provided on the outer end surface of the jacket (311) away from the corrugated pipe (313), and the protective cushion layer (36) is used for buffering after the outer end surface of the jacket (311) away from the corrugated pipe (313) abuts against the first section box girder (1) of the bridge.

10. A construction method for a bridge box girder structure according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Build supports on the bridge piers; S2. Hang the box girder on the supports of two adjacent piers; S3. Install anchoring devices on the box beam; S4, prestressing the prestressed tendons in the box girder by means of jacks and anchoring devices; S5. Install the inclined cables and anti-vibration ropes on the box girder; S6. Install anti-water seepage device on the box girder.

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