A reinforcement method for a prefabricated concrete small box beam shear reinforcement device based on UHPC prefabricated panels

Abstract

The present invention relates to an assembled shear-resistant reinforcement device for a small concrete box girder based on a UHPC prefabricated board and a reinforcement method thereof, comprising a UHPC prefabricated board assembled on the outer surface of the small box girder; a plurality of anchor bolt reserved holes are reserved on the outer surface of the UHPC prefabricated board, and correspondingly, anchor bolts corresponding to the anchor bolt reserved holes are pre-buried in the small box girder, the anchor bolts are inserted into the anchor bolt reserved holes, and are fastened by bolts to fit the UHPC prefabricated board to the outer surface of the small box girder; the advantages of the present invention are that a shear-resistant reinforcement method for a small box girder by enlarging the cross section method and the excellent performance of UHPC materials are combined, and from the perspective of assembly, the newly thickened UHPC prefabricated board is prefabricated in a factory and steam-cured at high temperature, which avoids on-site pouring and curing of concrete, and can fully guarantee the performance of the UHPC material; and there is no problem of later durability after reinforcement, and maintenance-free after reinforcement can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge repair and reinforcement devices, and in particular relates to a reinforcement method for a small concrete box girder assembled shear reinforcement device based on UHPC prefabricated panels. Background Art

[0002] Thanks to its advantages such as high torsional rigidity, low beam height, and clear structural stress, small concrete box girder bridges are widely used in small and medium span bridges. However, due to poor control of web thickness and vehicle overload, small box girder bridges often experience diagonal web shear cracks, which in turn leads to reduced shear bearing capacity and affects structural safety. The shear reinforcement methods for small box girders can be selected by gluing steel plates, increasing the cross-section with concrete, and gluing composite materials. However, these reinforcement methods also have certain problems. For example, steel plates often rust in the later stage of gluing steel plates, the on-site construction of increasing the cross-section with concrete is cumbersome, and the reinforcement effect of gluing composite materials is limited.

[0003] With the development and continuous promotion of ultra-high performance concrete (UHPC), UHPC has been gradually applied to bridge maintenance and reinforcement due to its good tensile properties and high durability, including orthotropic steel bridge deck paving treatment, hollow slab bridge hinge joint reinforcement, etc. However, since UHPC construction has relatively harsh curing conditions, it is often difficult to achieve the expected reinforcement effect by directly increasing the cross-section of the bridge by cast-in-place concrete and using it for shear reinforcement.

[0004] Improvements need to be made in view of the above technical problems. Summary of the invention

[0005] The present invention aims to overcome the defects in the prior art and provide a reinforcement method for a concrete small box girder assembled shear reinforcement device based on UHPC prefabricated panels, which has a simple structure, ingenious design, ensures reinforcement effect and improves reinforcement efficiency.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is: an assembled shear reinforcement device for a concrete small box girder based on a UHPC prefabricated panel, comprising a UHPC prefabricated panel assembled on the outer surface of the small box girder; a plurality of anchor bolt holes are reserved on the outer surface of the UHPC prefabricated panel, and correspondingly, anchor bolts corresponding to the anchor bolt holes are pre-embedded in the small box girder, the anchor bolts are inserted into the anchor bolt holes, and are fastened by bolts to fit the UHPC prefabricated panel to the outer surface of the small box girder.

[0007] As a preferred solution of the present invention, the small box beam and the UHPC prefabricated panel are bonded by an adhesive colloid.

[0008] As a preferred solution of the present invention, the anchor bolt reserved hole is an elliptical structure.

[0009] As a preferred solution of the present invention, the bottom of the UHPC prefabricated panel is on the same horizontal plane as the bottom of the web of the small box beam.

[0010] As a preferred solution of the present invention, a rubber sealing ring is installed on the edge of the UHPC prefabricated board, and the rubber sealing ring is attached to the periphery of the UHPC prefabricated board.

[0011] As a preferred solution of the present invention, a plurality of rubber gaskets are bonded inside the UHPC prefabricated panel, and the rubber gaskets are equidistantly arranged inside the UHPC prefabricated panel.

[0012] As a preferred solution of the present invention, a distance is left between the rubber gasket and the anchor bolt reserved hole.

[0013] As a preferred solution of the present invention, the thickness of the rubber gasket is consistent with the thickness of the bonding colloid.

[0014] As a preferred solution of the present invention, a glue injection nozzle is installed at the bottom of the UHPC prefabricated panel, and a glue discharge nozzle is installed at the top of the UHPC prefabricated panel.

[0015] A reinforcement method for a small concrete box beam assembled shear reinforcement device based on a UHPC prefabricated panel comprises the following steps:

[0016] Step 1: Prefabricate UHPC prefabricated panels in the factory according to the web height of the small box girder and the range to be shear reinforced. For easy installation, reserved holes for anchor bolts are required on the UHPC prefabricated panels.

[0017] Step 2: Locate the reinforcement area on site, roughen the surface of the concrete to be reinforced, and drill holes in the web of the small box beam to embed anchor bolts according to the positions of the anchor bolt holes on the UHPC precast panels;

[0018] Step 3: After the curing of the UHPC prefabricated panels is completed, install the rubber sealing rings and rubber gaskets;

[0019] Step 4: Install the UHPC prefabricated panels on site and fix them with anchor bolts, ensuring that the rubber gaskets and rubber sealing rings are in a compressed state. After compression, the anchor bolt holes reserved for the UHPC prefabricated panels are also sealed;

[0020] Step 5: Install the glue injection nozzle at the bottom of the UHPC precast panel and the glue outlet nozzle at the top, and perform a sealing test on the enclosed space enclosed by the UPHC panel and the web of the small box beam;

[0021] Step 6: Inject the adhesive colloid from the glue injection nozzle from bottom to top until the glue continues to flow out of the glue outlet nozzle, and then keep the pressure for a certain period of time after closing the glue outlet nozzle;

[0022] Step 7: Tighten the anchor bolts for a second time to apply a certain pre-pressure to the internal bonding colloid;

[0023] Step 8: After the adhesive colloid is cured, the shear reinforcement is completed.

[0024] The beneficial effects of the present invention are:

[0025] The advantages of the present invention are that it combines the shear reinforcement method of the small box girder by increasing the cross-section method and the excellent performance of the UHPC material. From the perspective of assembly, the newly thickened UHPC prefabricated panels are prefabricated in the factory and steam-cured at high temperature, avoiding on-site pouring and curing of concrete, and fully ensuring the performance of the UHPC material; the adhesive layer colloid adopts the pressure injection method and secondary pre-compression treatment to fully ensure the adhesion between the UHPC prefabricated panel and the web of the small box girder, and there is no problem of later durability after reinforcement, and maintenance-free after reinforcement can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a cross-sectional view of the shear reinforcement of the small box girder of the UHPC prefabricated plate according to an embodiment of the present invention;

[0027] Figure 2 This is an elevation view of the shear reinforcement of a small box girder of a UHPC prefabricated panel according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the outer surface of a UHPC prefabricated panel according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the inner surface of a UHPC prefabricated panel according to an embodiment of the present invention;

[0030] Reference numerals in the figure: small box beam 1, UHPC prefabricated panel 2, adhesive colloid 3, anchor bolt 4, anchor bolt reserved hole 5, glue injection nozzle 6, glue outlet nozzle 7, rubber sealing ring 8, rubber gasket 9. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Example:

[0034] like Figures 1 to 4 As shown, an assembled shear reinforcement device for a concrete small box girder based on a UHPC precast panel comprises a UHPC precast panel 2 assembled on the outer surface of a small box girder 1; a plurality of anchor bolt reserved holes 5 are reserved on the outer surface of the UHPC precast panel 2, and correspondingly, anchor bolts 4 corresponding to the anchor bolt reserved holes 5 are pre-embedded in the small box girder 1, and the anchor bolts 4 are inserted into the anchor bolt reserved holes 5 and fastened by bolts to fit the UHPC precast panel 2 to the outer surface of the small box girder 1.

[0035] The present invention provides a concrete small box girder assembly type shear reinforcement device based on UHPC prefabricated panels, which prefabricates UHPC prefabricated panels in a factory, and directly installs them on site and then injects glue to bond them to achieve shear reinforcement of the concrete small box girder web with increased cross-section. This method fully guarantees the tensile properties of UHPC by prefabricating UHPC prefabricated panels and assembling them on site, while avoiding on-site pouring and curing of UHPC, ensuring the reinforcement effect and improving the reinforcement efficiency.

[0036] The small box girder 1 and the UHPC prefabricated panel 2 are bonded by the bonding colloid 3; the small box girder 1 is adhered to the outer surface of the web of the small box girder 1 by the bonding colloid 3; the bonding colloid 3 shall adopt the Class A glue that meets the specifications and design requirements; after the UPHC prefabricated panel 2 is prefabricated in the factory and steam-cured at high temperature, in order to facilitate installation, the UHPC prefabricated panel 2 needs to reserve anchor bolt holes 5; the anchor bolt holes 5 are elliptical structures.

[0037] According to the web height of the small box girder 1 and the range to be shear reinforced, the UHPC prefabricated plate 2 is prefabricated in the factory, and the bottom of the UHPC prefabricated plate 2 is on the same horizontal plane as the bottom of the web of the small box girder 1; at the same time, the inner surface of the UHPC prefabricated plate 2 should also be roughened.

[0038] A rubber sealing ring 8 is installed at the edge of the UHPC prefabricated board 2 , and the rubber sealing ring 8 is attached to the periphery of the UHPC prefabricated board 2 ; it is used as an edge seal when the adhesive colloid 3 is injected into the UHPC prefabricated board 2 .

[0039] A plurality of rubber gaskets 9 are bonded to the inside of the UHPC precast panel 2. The rubber gaskets 9 are equidistantly arranged inside the UHPC precast panel 2 to control the thickness of the bonding colloid 3 between the UHPC precast panel 2 and the web of the small box beam 1. A spacing is left between the rubber gasket 9 and the anchor bolt reserved hole 5. This avoids damage to the rubber gasket 9 when the anchor bolt 4 is inserted into the anchor bolt reserved hole 5, thereby ensuring the safety of use. The thickness of the rubber gasket 9 is consistent with the thickness of the bonding colloid 3. This improves the stability and safety of the UHPC precast panel 2 bonded to the web of the small box beam 1.

[0040] A glue injection nozzle 6 is installed at the bottom of the UHPC prefabricated panel 2 , and a glue outlet nozzle 7 is installed at the top of the UHPC prefabricated panel 2 .

[0041] A reinforcement method for a small concrete box beam assembled shear reinforcement device based on a UHPC prefabricated panel comprises the following steps:

[0042] Step 1: prefabricate the UHPC prefabricated panels 2 in the factory according to the web height of the small box girder 1 and the range to be shear reinforced. For ease of installation, reserved anchor holes 5 need to be reserved on the UHPC prefabricated panels 2.

[0043] Step 2: Loft the reinforcement area on site, roughen the surface of the concrete to be reinforced, and drill holes in the web of the small box beam 1 to embed anchor bolts 4 according to the positions of the anchor bolt reserved holes 5 on the UHPC precast panels 2;

[0044] Step 3: After the curing of the UHPC prefabricated panel 2 is completed, the rubber sealing ring 8 and the rubber gasket 9 are installed;

[0045] Step 4: Install the UHPC prefabricated panel 2 on site and fix it with anchor bolts 4, ensure that the rubber gasket 9 and the rubber sealing ring 8 are in a compressed state, and after compression, the anchor bolt reserved holes 5 reserved for the UHPC prefabricated panel 2 are also sealed;

[0046] Step 5: Install the glue injection nozzle 6 at the bottom of the UHPC precast panel 2 and the glue outlet nozzle 7 at the top, and perform a sealing inspection on the enclosed space surrounded by the UHPC precast panel 2 and the web of the small box beam 1;

[0047] Step 6: Inject the adhesive colloid 3 from the glue injection nozzle 6 from bottom to top until the glue continues to flow out of the glue outlet nozzle 7, and then close the glue outlet nozzle 7 and continue to maintain the pressure for a certain period of time;

[0048] Step seven, tighten the anchor bolt 4 for a second time, and apply a certain pre-pressure to the internal bonding colloid 3;

[0049] Step eight, after the adhesive colloid 3 is cured, the shear reinforcement is completed.

[0050] The advantages of the present invention are that it combines the shear reinforcement method of the small box girder by increasing the cross-section method and the excellent performance of the UHPC material. From the perspective of assembly, the newly thickened UHPC prefabricated panels are prefabricated in the factory and steam-cured at high temperature, avoiding on-site pouring and curing of concrete, and fully ensuring the performance of the UHPC material; the adhesive layer colloid adopts the pressure injection method and secondary pre-compression treatment to fully ensure the adhesion between the UHPC prefabricated panel and the web of the small box girder, and there is no problem of later durability after reinforcement, and maintenance-free after reinforcement can be achieved.

[0051] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention; therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0052] Although the following terms are used more frequently in this paper: small box beam 1, UHPC prefabricated board 2, adhesive colloid 3, anchor bolt 4, anchor bolt reserved hole 5, glue injection nozzle 6, glue outlet nozzle 7, rubber sealing ring 8, rubber gasket 9, etc., the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A reinforcement method for a small concrete box beam assembled shear reinforcement device based on UHPC prefabricated panels, characterized in that: The following steps are involved: Step 1: prefabricate the UHPC prefabricated panels (2) in the factory according to the web height of the small box girder (1) and the range to be reinforced for shear resistance. For ease of installation, anchor bolt reserved holes (5) need to be reserved on the UHPC prefabricated panels (2); Step 2: Stake out the reinforcement area on site, roughen the surface of the concrete to be reinforced, and drill holes (4) in the web of the small box girder (1) to embed anchor bolts according to the positions of the anchor bolt reserved holes (5) on the UHPC precast panels (2); Step 3: After the curing of the UHPC prefabricated panel (2) is completed, a rubber sealing ring (8) and a rubber gasket (9) are installed; Step 4: Install the UHPC prefabricated panel (2) on site and fix it with anchor bolts (4), ensure that the rubber gasket (9) and the rubber sealing ring (8) are in a compressed state, and after compression, the anchor bolt reserved hole (5) reserved for the UHPC prefabricated panel (2) is also sealed; Step 5: Install a glue injection nozzle (6) at the bottom of the UHPC precast panel (2), install a glue outlet nozzle (7) at the top, and perform a sealing test on the enclosed space enclosed by the UHPC panel and the web of the small box beam; Step six, injecting the adhesive colloid (3) from the glue injection nozzle (6) from bottom to top until the glue continues to flow out of the glue outlet nozzle (7), and then closing the glue outlet nozzle (7) and continuing to maintain the pressure for a certain period of time; Step seven, tighten the anchor bolt (4) for a second time, and apply a certain pre-pressure to the internal bonding colloid (3); Step 8, after the adhesive colloid (3) is solidified, the shear reinforcement is completed; The UHPC prefabricated panel-based concrete small box girder assembled shear reinforcement device comprises a UHPC prefabricated panel (2) assembled on the outer surface of the small box girder (1); a plurality of anchor bolt reserved holes (5) are reserved on the outer surface of the UHPC prefabricated panel (2); correspondingly, anchor bolts (4) corresponding to the anchor bolt reserved holes (5) are pre-embedded in the small box girder (1); the anchor bolts (4) are inserted into the anchor bolt reserved holes (5) and fastened by bolts to fit the UHPC prefabricated panel (2) to the outer surface of the small box girder (1); the small box girder (1) and the UHPC prefabricated panel (2) are bonded by a bonding colloid (3); the UHPC prefabricated panel (2) is bonded to the outer surface of the small box girder (1 ... The bottom of the HPC precast plate (2) is on the same horizontal plane as the bottom of the web of the small box beam (1); the anchor bolt reserved hole (5) is an elliptical structure; a rubber sealing ring (8) is installed on the edge of the UHPC precast plate (2), and the rubber sealing ring (8) is attached to the periphery of the UHPC precast plate (2); a plurality of rubber gaskets (9) are attached to the inside of the UHPC precast plate (2), and the rubber gaskets (9) are arranged equidistantly inside the UHPC precast plate (2); a spacing is left between the rubber gasket (9) and the anchor bolt reserved hole (5); the thickness of the rubber gasket (9) is consistent with the thickness of the bonding colloid (3); A glue injection nozzle (6) is installed at the bottom of the UHPC prefabricated panel (2), and a glue discharge nozzle (7) is installed at the top of the UHPC prefabricated panel (2).

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