Reinforced concrete beam secondary reinforcing device and method without dismantling reinforcing steel plate

Abstract

The invention provides a secondary reinforcing device and method for a reinforced concrete beam without dismantling a reinforcing steel plate, the device comprises an anchoring part, a connecting steel bar and a reinforced concrete layer, the steel plate is attached to the surface of the concrete beam and the reinforced steel plate, and the steel plate and the concrete beam are connected and anchored through bolts; the anchoring parts are connected with the concrete beam in an anchoring mode, meanwhile, the anchoring parts are arranged below the steel plate in a striding mode, the anchoring parts are connected into a whole through the connecting steel bars, and the area where the anchoring parts, the connecting steel bars and the steel plate are located is filled with the reinforced concrete pattern layer. On the basis that an existing reinforcing steel plate does not need to be dismantled, the flexural capacity and rigidity of the concrete beam are improved, construction steps are reduced, the construction efficiency is improved, meanwhile, the adopted geopolymer concrete is low in carbon emission and high in fireproof performance, and it can be guaranteed that the construction process is environmentally friendly and resistant to high temperature in the construction process.

Description

Technical Field

[0001] The invention relates to the technical field of concrete reinforcement, and in particular to a secondary reinforcement device and method for reinforced concrete beams without removing reinforcement steel plates. Background Art

[0002] Bolt-anchored steel plate reinforced concrete beam is a common structural reinforcement technology that can significantly improve the bending bearing capacity, stiffness and seismic performance of reinforced concrete beams, and has been widely used in the repair and reinforcement of bridges and building structures. However, under the harsh service environment, not only the existing bolt-anchored steel plate reinforced concrete beam structure itself may be further damaged, such as internal steel corrosion and deterioration of concrete mechanical properties, but even the steel plates and bolts in the reinforcement system may also suffer from rust diseases, and the mechanical properties of the bonding structural adhesive will also degrade, affecting the coordinated force between the steel plate and the concrete beam, resulting in the gradual degradation of the mechanical properties of the primary bolt-anchored steel plate reinforced concrete beam and the need for secondary reinforcement.

[0003] At present, the common measures for strengthening concrete structures mainly include increasing the cross-section method, externally bonding carbon fiber reinforced composites method and prestressed reinforcement method. Among them, the increasing cross-section method usually involves planting reinforcement bars on the cross-section of existing concrete beams and pouring a certain thickness of concrete to improve the structural bearing capacity; externally bonding carbon fiber reinforced composites involves bonding carbon fiber reinforced composite fabrics or plates on the tensile side of existing concrete beams, using the high strength and light weight of carbon fiber reinforced composites to improve the structural bearing capacity; the prestressed reinforcement method involves adding prestressed steel strands or fiber composites to existing concrete beams to improve the structural bending bearing capacity.

[0004] However, for concrete beams that have been reinforced with bolt-anchored steel plates, the above existing concrete structure reinforcement methods are still insufficient. Specifically, the section-adding method usually requires the removal of the existing concrete beam protective layer and steel plate. In addition, it is necessary to plant reinforcement to improve the coordinated force between the post-cast section and the existing section, which requires a large amount of on-site work; the bonding of carbon fiber reinforced composites also requires the removal of the steel plate and anchor bolts in the primary reinforcement to provide a working surface, and the bonding structural adhesive also has the risk of mechanical performance degradation in harsh service environments; the prestressed reinforcement method requires the addition of anchoring devices at the ends of existing concrete beams, and the tensioning construction work is relatively complicated. Therefore, the existing concrete structure reinforcement technology cannot meet the secondary reinforcement needs of concrete beams reinforced with bolt-anchored steel plates. Summary of the invention

[0005] The purpose of the present invention is to provide a secondary reinforcement scheme for reinforced concrete beams without removing the reinforcing steel plates in response to the deficiencies in the above-mentioned background technology. The scheme can effectively improve the bonding performance between the post-cast reinforcement layer and the existing concrete beam without removing the existing reinforcing steel plates, while simplifying the secondary reinforcement construction process and improving the efficiency of structural reinforcement.

[0006] In order to achieve the above-mentioned object, the present invention provides a secondary reinforcement anchoring device for steel plate reinforced reinforced concrete beam, comprising an anchor, connecting steel bars and a reinforced concrete layer, wherein the steel plate is fitted to the surface of the concrete beam and is connected and anchored by bolts;

[0007] The anchor is anchored to the concrete beam and is arranged across the bottom of the steel plate. The anchors are connected as a whole by the connecting steel bars. The reinforced concrete layer is filled in the area where the anchor, the connecting steel bars and the steel plate are located.

[0008] Furthermore, the anchor comprises a top vertical plate, a flange plate and a bottom vertical plate; a slot is provided on the top vertical plate, the slot is used to accommodate the steel plate, and after the anchor is installed in place, there is a gap between the slot and the steel plate; the flange plate is horizontally arranged, and the bottom vertical plate is arranged below the top vertical plate.

[0009] Furthermore, a plurality of the notches are provided on the top vertical plate of a single anchor, and the protruding portion of the top vertical plate after the notches are anchor points connected to the concrete beam.

[0010] Furthermore, the flange plate and the bottom vertical plate are both provided with openings, and the openings are used to improve the fluidity of the reinforced concrete layer when it is filled, and to make the combination with the reinforced concrete layer more firm.

[0011] Furthermore, the openings on the flange plate and the bottom vertical plate are arranged to be staggered.

[0012] Furthermore, the anchor is provided with a welding hole, and the welding hole is connected to the connecting steel bar and fixed by welding.

[0013] Furthermore, the welding holes are opened on the top vertical plate.

[0014] Furthermore, a plurality of anchors are evenly arranged along the longitudinal direction of the concrete beam, and each anchor is distributed along the transverse direction of the concrete beam.

[0015] Furthermore, the reinforced concrete layer is filled with geopolymer concrete.

[0016] The present invention also provides a secondary reinforcement method for reinforced concrete beams without removing the reinforcement steel plate, using the secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate as described above, comprising the following steps:

[0017] S1, surface treatment of existing concrete beams, roughening and dust removal;

[0018] S2, grinding the existing steel plate to remove surface rust and dust;

[0019] S3, drilling holes in the concrete beam, and after cleaning the holes, implanting anchors into the holes using anchor glue, and installing connecting steel bars between the anchors and welding them to fix;

[0020] S4, setting a filling mold in the area to be reinforced;

[0021] S5, pouring geopolymer concrete in the filling mold area to a predetermined depth;

[0022] S6, cure to design strength and then remove the formwork.

[0023] The above scheme of the present invention has the following beneficial effects:

[0024] The secondary reinforcement device and method for reinforced concrete beams without removing the reinforcing steel plate provided by the present invention have better integrity than the existing concrete beams simply reinforced with embedded steel bars. The flange plates, bottom vertical plates, etc. of the anchors can effectively increase the mechanical bite and interaction between the anchors and the reinforced concrete layer, significantly improving the anti-peeling ability of the reinforced concrete layer. At the same time, they can also provide lateral resistance when the concrete beam is bent. On the basis of not having to remove the existing reinforcing steel plates, effective constraints are provided for the newly added reinforced concrete layer, improving the bending bearing capacity and rigidity of the concrete beam. At the same time, the openings of the flange plates and bottom vertical plates of the anchors can effectively improve the passability of the geopolymer concrete, obtaining a denser reinforced concrete layer, and avoiding local stress concentration caused by the gap between the anchors and the reinforced concrete layer.

[0025] In the present invention, geopolymer concrete is used to replace traditional concrete for secondary reinforcement of concrete beams. Since geopolymer concrete has good bonding performance with existing ordinary concrete beams and steel plates, geopolymer concrete is directly poured on the surface-treated steel plates and beam bodies, which can be synergistically stressed to avoid removing the steel plates during secondary reinforcement, reduce construction steps, and improve construction efficiency. The reinforced concrete layer of geopolymer concrete can effectively isolate the corrosion of external corrosive media on steel plates and anchors, and improve the durability of the reinforcement system. Geopolymer concrete has low carbon emissions and strong fire resistance, and can ensure green environmental protection and high temperature resistance during construction.

[0026] Other beneficial effects of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 It is a front view of the overall structure of the present invention;

[0029] Figure 3It is a schematic diagram of the connection details of the anchor member of the present invention;

[0030] Figure 4 It is a schematic diagram of the structure of the anchor member of the present invention;

[0031] Figure 5 The present invention is a flow chart of the method.

[0032] [Description of Reference Numerals]

[0033] 10-anchor; 11-top vertical plate; 12-flange plate; 13-bottom vertical plate; 14-slot; 15-welding hole; 20-connecting steel bar; 30-reinforced concrete layer; 40-concrete beam; 50-steel plate; 60-bolt. DETAILED DESCRIPTION

[0034] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a locking 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 an indirect connection 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.

[0037] like Figure 1-Figure 3As shown, an embodiment of the present invention provides a secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate, comprising an anchor 10, a connecting steel bar 20, and a reinforced concrete layer 30, which performs secondary reinforcement on the primary reinforcement structure of the concrete beam 40, such as the steel plate 50 and the bolt 60. The steel plate 50 is attached to the surface of the concrete beam 40, connected and anchored by the bolt 60, to form a primary reinforcement structure.

[0038] At the same time Figure 4 As shown, the anchor 10 is arranged in a cross shape, including a top vertical plate 11, a flange plate 12 and a bottom vertical plate 13. Among them, a notch 14 is provided on the top vertical plate 11, and the notch 14 is used to accommodate the steel plate 50 so that the top vertical plate 11 can be installed smoothly. Of course, after the anchor 10 is installed in place, the notch 14 and the steel plate 50 will not be in direct contact, and the spacing is preferably about 10 mm, and the reinforced concrete layer 30 is also filled in between. Considering the actual situation, there is usually a preset spacing between two steel plates 50. Therefore, as a preferred embodiment, in this embodiment, three notches 14 are arranged on the top vertical plate 11 of a single anchor 10, and the width of the notches 14 on both sides matches the width of the steel plate 50, and the center notch 14 corresponds to the position between two adjacent steel plates 50. At the same time, for the top vertical plate 11, the protruding part after the notch is opened is fixedly connected to the concrete beam 40 as an anchor point. It is understandable that the central slot 14 is provided to reduce the size of the anchor point and avoid cracking caused by drilling too wide a hole in the concrete beam 40. Those skilled in the art can flexibly set the slot 14 based on actual conditions to adapt to different numbers of steel plates 50.

[0039] The flange plate 12 and the bottom vertical plate 13 of the anchor 10 are used to further improve the transverse strength and bending resistance of the anchor 10 and the entire concrete beam 40. It can be understood that, under the premise that the top vertical plate 11 of the anchor 10 is grooved, the combination of the flange plate 12 and the bottom vertical plate 13 of the anchor 10 can be regarded as a T-beam, and is distributed transversely relative to the concrete beam 40, so the transverse bending strength of the concrete beam 40 can be improved.

[0040] As a preferred embodiment, in this embodiment, both the flange plate 12 and the bottom vertical plate 13 are provided with openings, which are preferably semicircular. The openings provide better fluidity during subsequent filling of the reinforced concrete layer 30, and avoid the generation of air bubbles that affect the filling quality. At the same time, the openings provide a stronger bond between the anchor 10 and the reinforced concrete layer 30, and provide better anti-peeling performance, thereby avoiding the segregation of the reinforced concrete layer 30 in a long-term state.

[0041] As a preferred implementation, the openings on the flange plate 12 and the bottom vertical plate 13 in this embodiment are staggered to avoid significant weakening of the lateral bending and shearing performance of the anchor 10 at the same position, thereby further improving the reliability of the anchor 10.

[0042] In this embodiment, the connecting steel bars 20 are used to connect the anchors 10 at different positions on the concrete beam 40 so that the different anchors 10 are connected into an integrated structure. When a certain anchor 10 and the concrete beam 40 become loose in a long-term state, they can still provide stable support, thereby improving the overall strength and firmness.

[0043] Among them, the anchor 10 is provided with a welding hole 15, which can be perforated or non-perforated, and is used for the connection steel bar 20 to pass through or insert the end, and then weld to connect the connection steel bar 20 and the anchor 10 as a whole. It should be noted that the connection steel bar 20 is distributed along the longitudinal direction of the concrete beam 40, and multiple transversely distributed anchors 10 are connected as a whole. As a preferred embodiment, in this embodiment, the welding hole 15 is opened at the position of the top vertical plate 11, based on the fact that the top vertical plate 11 hardly participates in the bending strength of the T-beam, and therefore does not affect the transverse bending performance of the anchor 10.

[0044] It should be noted that it is best to evenly arrange multiple anchors 10 along the longitudinal direction of the concrete beam 40 to ensure uniform support for the reinforced concrete layer 30, the steel plate 50, and the concrete beam 40. At the same time, since the anchor 10 can cross the steel plate 50, the distance between two adjacent anchors 10 can be set relatively small, further improving the support strength. Correspondingly, the connecting steel bars 20 can adopt the same length specification, and the welding holes 15 can still connect all the anchors 10 in sequence through the connecting steel bars 20 of a single specification without perforation.

[0045] In this embodiment, the reinforced concrete layer 30 is filled with geopolymer concrete (GPC). Compared with ordinary concrete, geopolymer concrete has lower carbon emissions and is more environmentally friendly. In addition, it has stronger fire resistance and can play a role in green environmental protection and high temperature resistance. By setting the reinforced concrete layer 30, the existing primary reinforcement structure, anchor 10, connecting steel bar 20, etc. can be coated, which better avoids the corrosion of steel structure, especially steel plate 50, thereby further improving the reliability of concrete beam 40 through secondary reinforcement.

[0046] It should be noted that when filling the reinforced concrete layer 30, a filling mold with a certain area and depth is first installed, and then the geopolymer concrete is filled into the filling mold to shape and cure the geopolymer concrete until the geopolymer concrete reaches a preset strength, so that the concrete beam 40 can be reinforced for the second time.

[0047] It should be noted that the geopolymer concrete in this embodiment includes the following weight ratios: water glass modulus is 1.2, sodium hydroxide concentration is 12 mol / L, ratio of gangue to slag is 6:4, bone glue ratio is 3.5, water-binder ratio is 0.38, and sand ratio is 35%. The preparation of geopolymer concrete includes: refining raw materials such as gangue, slag, and bone glue; dissolving sodium hydroxide in water and adding water glass to make an alkaline solution; mixing the raw materials and the alkaline solution in a certain proportion to form a castable slurry. The mixed slurry is poured into the aforementioned filling mold. After proper temperature control and curing, the geopolymer concrete will gradually harden to form a solid structure.

[0048] It is worth mentioning that the anchor 10 and the like in this embodiment are compatible with the steel plate 50 and are easy to manufacture in a standardized manner, including the standardization of the size of the notch 14 and the specifications of the connecting steel bars 20, so as to facilitate the standardization of the installation and improve the installation efficiency and quality.

[0049] Based on the same inventive concept, this embodiment also provides a secondary reinforcement method for reinforced concrete beams without removing the reinforcement steel plate, such as Figure 5 As shown, the following steps are included:

[0050] S1, thoroughly clean the surfaces of the concrete beam 40 and the steel plate 50 to remove loose particles, dust, oil stains and other pollutants to ensure good bonding between the subsequent reinforced concrete layer 30 and the concrete beam 40 and the steel plate 50.

[0051] S2, grinding the existing steel plate 50, using a grinding tool to gently press the grinding wheel or abrasive belt on the surface of the steel plate 50, maintaining a certain pressure, and moving at a uniform speed to avoid staying in one place for too long to generate excessive heat and cause deformation or discoloration of the surface of the steel plate 50. After grinding, remove surface rust and dust to ensure that the surface is clean in preparation for subsequent processing.

[0052] It should be noted that further grinding can be performed using finer grinding wheels or belts until the desired surface roughness is achieved.

[0053] S3, drill a hole at the bottom of the concrete beam 40, clean and remove loose particles in the hole, insert the top vertical plate 11 (anchor point) of the anchor 10 into the hole, fix it with anchor glue, and then insert the connecting steel bar 20 through the welding hole 15 between the anchors 10 and weld it to fix.

[0054] S4, determine the size, shape and structure of the filling mold, select the appropriate template material, cut the template material into the required size according to the design drawings, assemble the cut template into a complete filling mold according to the design requirements, and make preliminary adjustments and fixations.

[0055] It should be noted that during assembly, the horizontality and verticality of the templates must be ensured, as well as the firmness of the connections between the templates, and appropriate reinforcement can be carried out.

[0056] S5, slowly pouring the geopolymer concrete into the filling mold to ensure that the geopolymer concrete is dense and reaches a predetermined depth.

[0057] S6, curing the geopolymer concrete and removing the formwork to obtain a reinforced concrete layer 30.

[0058] Specifically, after the geopolymer concrete is poured, proper curing is carried out to promote it to reach the designed development strength. The curing method may include the use of curing agents, etc. After the geopolymer concrete reaches the designed strength, the formwork is removed. Be careful when removing the formwork to avoid damage to the newly poured geopolymer concrete. According to the specific formula of the geopolymer concrete and the environmental conditions, a suitable curing plan is formulated to ensure that the curing continues for a period of time to promote the geopolymer concrete to meet the designed strength after hardening.

[0059] From the above secondary reinforcement device and method for reinforced concrete beams without removing the reinforcing steel plate, it can be seen that the solution provided by this embodiment has better integrity than the existing concrete beam 40 simply reinforced with embedded steel bars. The flange plate 12, the bottom vertical plate 13, etc. of the anchor 10 can effectively increase the mechanical bite effect between the reinforced concrete layer 30, significantly improve the anti-stripping ability of the reinforced concrete layer 30, and also provide lateral resistance when the concrete beam 40 is bent. Without the need to remove the existing reinforcing steel plate 50, an effective constraint is provided for the newly added reinforced concrete layer 30, thereby improving the bending bearing capacity and stiffness of the concrete beam 40. At the same time, the openings of the flange plate 12 and the bottom vertical plate 13 of the anchor 10 can effectively improve the passability of the geopolymer concrete, thereby obtaining a denser reinforced concrete layer 30 and avoiding local stress concentration caused by the gap between the anchor 10 and the reinforced concrete layer 30.

[0060] In addition, geopolymer concrete is used instead of traditional concrete for secondary reinforcement of the concrete beam 40. Since geopolymer concrete has good bonding properties with the existing ordinary concrete beam 40 and steel plate 50, the geopolymer concrete is directly poured on the surface-treated steel plate 50 and the beam body, which can coordinate the force and avoid the removal of the steel plate 50 during secondary reinforcement, thereby reducing the construction steps and improving the construction efficiency. The reinforced concrete layer 30 of the geopolymer concrete can effectively isolate the corrosion of the steel plate 50 and the anchor 10 by external corrosive media, thereby improving the durability of the reinforcement system. In addition, the geopolymer concrete has low carbon emissions and strong fire resistance, which can ensure green environmental protection and high temperature resistance during the construction process.

[0061] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate, characterized in that: It includes anchors, connecting steel bars and reinforced concrete layers. For concrete beams and reinforced steel plates, the steel plates are fitted to the surface of the concrete beams and are connected and anchored by bolts; The anchor is anchored to the concrete beam and is arranged across the bottom of the steel plate. The anchors are connected as a whole by the connecting steel bars. The reinforced concrete layer is filled in the area where the anchor, the connecting steel bars and the steel plate are located.

2. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 1 is characterized in that: The anchor comprises a top vertical plate, a flange plate and a bottom vertical plate; a slot is provided on the top vertical plate, the slot is used to accommodate the steel plate, and after the anchor is installed in place, there is a gap between the slot and the steel plate; the flange plate is horizontally arranged, and the bottom vertical plate is arranged below the top vertical plate.

3. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 2, characterized in that: A plurality of the notches are arranged on the top vertical plate of a single anchoring piece, and the protruding portion of the top vertical plate after the notches are anchoring points connected to the concrete beam.

4. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 2, characterized in that: The flange plate and the bottom vertical plate are both provided with openings, and the openings are used to improve the fluidity of the reinforced concrete layer when it is filled, and to make the combination with the reinforced concrete layer more firm.

5. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 4, characterized in that: The openings on the flange plate and the bottom vertical plate are arranged to be staggered.

6. A secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 1 or 2, characterized in that: The anchor is provided with a welding hole, and the welding hole is connected to the connecting steel bar and fixed by welding.

7. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 6, characterized in that: The welding holes are formed on the top vertical plate.

8. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 1, characterized in that: A plurality of anchors are evenly arranged along the longitudinal direction of the concrete beam, and each anchor is distributed along the transverse direction of the concrete beam.

9. The secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate according to claim 1, characterized in that: The reinforced concrete layer is filled with geopolymer concrete.

10. A secondary reinforcement method for reinforced concrete beams without removing the reinforcement steel plate, using a secondary reinforcement device for reinforced concrete beams without removing the reinforcement steel plate as claimed in any one of claims 1 to 9, characterized in that: The steps include: S1, surface treatment of existing concrete beams, roughening and dust removal; S2, grinding the existing steel plate to remove surface rust and dust; S3, drilling holes in the concrete beam, cleaning the holes, implanting anchors into the holes using rebar glue, and installing connecting steel bars between the anchors and welding them in place; S4, setting a filling mold in the area to be reinforced; S5, pouring geopolymer concrete in the filling mold area to a predetermined depth; S6, cure to design strength and then remove the formwork.

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