FRP grating-geopolymer composite component and shear-resistant reinforced concrete beam

Abstract

The utility model discloses an FRP grating-geopolymer composite component and a shear-resistant reinforced concrete beam, the FRP grating-geopolymer composite component comprises an FRP grating and a geopolymer component, one side surface of the geopolymer component is provided with a component groove, and the FRP grating is laid in the component groove. The bearing capacity, the energy dissipation capacity, the shear capacity and the durability of the concrete beam can be greatly improved, and meanwhile due to the fact that the structure is simple, cost is low, economical efficiency is considered, and the concrete beam is worthy of application and popularization.

Description

Technical Field

[0001] The invention relates to the technical field of construction, and in particular to an FRP grid-geopolymer composite component and a shear-resistant reinforced concrete beam thereof. Background Art

[0002] As the service life of reinforced concrete structures increases, due to material aging and environmental corrosion or impact, especially the reduction of durability and shear bearing capacity of reinforced concrete beams, the safety of the main structure is affected, so maintenance is required.

[0003] At present, the traditional methods of strengthening reinforced concrete beams against shear mainly include increasing the cross-section, replacing concrete, and wrapping steel plates. However, there are disadvantages such as increasing the deadweight of the structure, high construction difficulty, poor corrosion resistance, and long reinforcement period. With the development of science and technology, FRP is a fiber-reinforced material that can be used as a lightweight, high-strength, and corrosion-resistant material and has been widely used in the field of building reinforcement.

[0004] The bonding strength between FRP material and concrete beam surface is mainly provided by interface agents such as epoxy resin. Since epoxy resin has poor bonding performance in low temperature and humid environment and low compatibility with substrate, the bonding strength between FRP material and concrete interface is reduced, which is prone to peeling damage. At the same time, the reinforcement material is directly exposed to the external environment and is susceptible to environmental wear and collision. Therefore, how to improve the utilization rate of FRP and construction efficiency has application and promotion value.

[0005] The defects of the existing technology are that the reinforcement material is directly exposed to the external environment, which is susceptible to environmental damage, wear and collision, the reinforcement layer is prone to peeling and damage, the FRP grid utilization rate is low, and the strength is not fully exerted. At the same time, reinforced concrete beams often need formwork during the reinforcement process, but the turnover rate of the formwork is low, which not only leads to waste of resources, but also greatly reduces the progress of construction. Summary of the invention

[0006] The purpose of the present invention is to provide a FRP grid-geopolymer composite component and a shear-resistant reinforced concrete beam, which greatly improves the bearing capacity, energy dissipation capacity, shear resistance and durability of the concrete beam. At the same time, due to its simple structure, low cost and economical consideration, it is worthy of application and promotion.

[0007] The technical solution adopted by the present invention is:

[0008] An FRP grid-geopolymer composite component comprises an FRP grid and a geopolymer component. A concave groove is arranged on one side surface of the geopolymer component, and the FRP grid is laid in the concave groove.

[0009] Preferably, a boss is provided on the edge of one side of the geopolymer component to form a recessed groove.

[0010] Preferably, the geopolymer component is a plate-shaped structure, and the concave groove is arranged on the front or rear side of the plate-shaped structure.

[0011] Preferably, the recessed groove is rectangular.

[0012] Preferably, a plurality of reserved holes are provided on the geopolymer component; the reserved holes are arranged within the range of the recessed groove.

[0013] Preferably, the FRP grid is a FRP mesh formed by impregnating high-performance continuous fibers in a corrosion-resistant epoxy resin and curing the resulting FRP mesh.

[0014] Preferably, the FRP grating includes any one of a BFRP grating, a CFRP grating, and a GFRP grating.

[0015] Preferably, BFRP is a basalt fiber reinforced composite material, CFRP is a carbon fiber reinforced composite material, and GFRP is a glass fiber reinforced composite material.

[0016] Preferably, the thickness of the FRP grid is 1-3 mm.

[0017] Preferably, the depth of the concave groove is 1 / 2 to 1 / 3 of the total thickness of the geopolymer component; that is, the FRP grid is placed at 1 / 2 to 1 / 3 of the thickness of the edges at both ends of the geopolymer component.

[0018] Preferably, the thickness of the geopolymer component at both ends is 35 mm, the thickness of the middle portion is 20 mm, and the depth of the rectangular recessed groove is 15 mm.

[0019] A FRP grid-geopolymer composite component shear-resistant reinforced concrete beam comprises a reinforced concrete beam and the FRP grid-geopolymer composite component as described above, wherein the FRP grid-geopolymer composite component is arranged on the front and rear side surfaces of the reinforced concrete beam and anchored on the reinforced concrete beam, a recessed groove is arranged between the reinforced concrete beam and the geopolymer component, and is arranged close to the reinforced concrete beam, and the space enclosed by the recessed groove and the reinforced concrete beam is filled with geopolymer mortar; the recessed groove is open toward the reinforced concrete beam, and a pouring port is provided at the upper end of the recessed groove for pouring geopolymer mortar.

[0020] Preferably, the recessed groove is rectangular.

[0021] The high-strength bolts pass through the reserved holes on the geopolymer components of the FRP grid-geopolymer composite components.

[0022] Preferably, the FRP grid-geopolymer composite member is anchored to the shear span region of the reinforced concrete beam by high-strength bolts.

[0023] Preferably, a roughening groove is provided on one side surface of the reinforced concrete beam in contact with the FRP grid-geopolymer composite component, and the roughening groove is arranged within the component groove range.

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

[0025] The utility model places FRP grille in geopolymer, which can solve the problem of easy aging of epoxy resin on the one hand, and has strong bonding ability with concrete interface, and can effectively avoid wear and tear caused by direct exposure of FRP grille to the outside world on the other hand. The ultra-high toughness of geopolymer can make up for the disadvantage of low energy consumption of FRP grille, improve the utilization rate of FRP grille, and when used in reinforced concrete beams, it can enhance the shear resistance and durability of reinforced concrete beams, greatly improve the bearing capacity, ductility and energy consumption capacity of reinforced concrete beams, and at the same time, the component itself can be used as a mold when reinforcing concrete beams, which can avoid the installation and disassembly of templates and greatly improve the construction efficiency; at the same time, due to its simple structure, low cost and economic efficiency, it is worthy of application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of an FRP grid-geopolymer composite component in an embodiment of the present invention;

[0027] Figure 2 yes Figure 1 A-direction view;

[0028] Figure 3 2. It is a front view of a reinforced concrete beam reinforced with shear strength by a FRP grid-geopolymer composite member according to an embodiment of the present invention;

[0029] Figure 4 yes Figure 3 Left view of

[0030] Figure 5 yes Figure 3 BB cross-sectional view.

[0031] In the figure: 1-FRP grid, 2-geopolymer component, 3-high-strength bolt, 4-reinforced concrete beam, 5-roughened groove, 6-depressed groove, 7-reserved hole. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] In the description of the present invention, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like are involved, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is 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 a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0034] 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 directly connected or indirectly connected through an intermediate medium. It can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] Example 1

[0036] An FRP grid-geopolymer composite component comprises an FRP grid 1 and a geopolymer component 2. A concave groove 6 is provided on the inner side surface of the geopolymer component 2, and the FRP grid 1 is laid in the concave groove 6.

[0037] Furthermore, a boss is provided on the edge of one side of the geopolymer component 2 to form a recessed groove 6 .

[0038] Further, the geopolymer component 2 is a plate-shaped structure, and the concave groove 6 is arranged on the front or rear side of the plate-shaped structure.

[0039] Furthermore, the concave groove 6 is rectangular.

[0040] Furthermore, a plurality of reserved holes 7 are provided on the geopolymer component 2 ; the reserved holes 7 are arranged within the range of the concave groove 6 .

[0041] Furthermore, the FRP grid 1 is formed by impregnating high-performance continuous fibers into a corrosion-resistant epoxy resin and curing the resulting FRP grid.

[0042] Further, the FRP grating 1 includes any one of a BFRP grating, a CFRP grating, and a GFRP grating.

[0043] Furthermore, BFRP is a basalt fiber reinforced composite material, CFRP is a carbon fiber reinforced composite material, and GFRP is a glass fiber reinforced composite material.

[0044] Example 2

[0045] On the basis of Example 1, the parameters of the FRP grid and the geopolymer component are further limited, and the performance of Example 2 after the limitation is better.

[0046] Furthermore, the thickness of the FRP grid 1 is 1-3 mm.

[0047] Furthermore, the depth of the concave groove 6 is 1 / 2 to 1 / 3 of the total thickness of the geopolymer component 2 ; that is, the FRP grid 1 is placed at 1 / 2 to 1 / 3 of the thickness of the edges at both ends of the geopolymer component 2 .

[0048] Furthermore, the thickness of the two ends of the geopolymer component is 35 mm, the thickness of the middle part is 20 mm, and the depth of the rectangular concave groove 6 is 15 mm.

[0049] Example 3

[0050] A FRP grid-geopolymer composite component shear-resistant reinforced concrete beam comprises a reinforced concrete beam 4 and the FRP grid-geopolymer composite component as described above, wherein the FRP grid-geopolymer composite component is arranged on the front and rear side surfaces of the reinforced concrete beam 4 and anchored on the reinforced concrete beam 4, a recessed groove 6 is arranged between the reinforced concrete beam 4 and the geopolymer component, and is arranged adjacent to the reinforced concrete beam 4, and the space enclosed by the recessed groove 6 and the reinforced concrete beam 4 is filled with geopolymer mortar; the recessed groove 6 is open toward the reinforced concrete beam 4, and a pouring port is provided at the upper end of the recessed groove 6 for pouring geopolymer mortar.

[0051] The FRP grid-geopolymer composite components on both sides are arranged symmetrically with the reinforced concrete beams 4 .

[0052] Furthermore, the high-strength bolts 3 pass through the reserved holes 7 on the geopolymer component of the FRP grid-geopolymer composite component.

[0053] Furthermore, the FRP grid-geopolymer composite component is anchored to the shear span area of ​​the reinforced concrete beam 4 by high-strength bolts 3; anchoring by high-strength bolts 3 effectively avoids peeling damage of the reinforcement layer.

[0054] Furthermore, a plurality of roughened grooves 5 are provided on one side of the reinforced concrete beam 4 in contact with the FRP grid-geopolymer composite component (i.e., a side of the reinforced concrete beam 4 that is in contact with the recessed groove 6), and the roughened grooves 5 are arranged within the range of the recessed groove 6; after the FRP grid-geopolymer composite component is anchored on the reinforced concrete beam 4, since the roughened grooves 5 and the recessed groove 6 are in the same space, geopolymer mortar is poured into the recessed groove 6, and the geopolymer mortar also flows into the roughened grooves 5.

[0055] Furthermore, the concave groove 6 is rectangular; and the reinforced concrete beam 4 is a reinforced concrete rectangular beam.

[0056] Furthermore, the surface layer of the reinforced concrete beam 4 is a protective layer of concrete, the thickness of the two ends of the geopolymer component is 35mm, the thickness of the middle part is 20mm, and the depth of the rectangular recessed groove 6 is 15mm. The FRP grid is placed at 1 / 2~1 / 3 of the thickness of the edge of the two ends of the component, and the FRP grid is formed by impregnating high-performance continuous fibers in corrosion-resistant epoxy resin and curing. The types of FRP grids can be BFRP (basalt fiber reinforced composite material) grids, CFRP (carbon fiber reinforced composite material) grids, and GFRP (glass fiber reinforced composite material) grids. The grid thickness is 1~3mm, and the size can be selected from 25mm×25mm, 50mm×50mm, etc. At the same time, 4 holes with a diameter of 4mm are left on the component to facilitate the later fixing of high-strength bolts 3. The high-strength bolt 3 is a 12.9 grade hexagonal alloy steel, the head thickness and head diameter of the bolt are 8mm and 13mm respectively, the thread diameter is 4mm, the pitch is 1.25mm, and the thread length is 60mm. The prefabricated FRP grid-geopolymer composite component is anchored in the shear span area of ​​the reinforced concrete beam 4 by high-strength bolts 3. Then, the geopolymer mortar is poured into the concave groove 6.

[0057] Working principle of the present invention: A FRP grid-geopolymer composite component is composed of an FRP grid and a geopolymer component; the FRP grid 1 is placed in the geopolymer component 2, the thickness of the two ends and the bottom of the composite component is 35mm, the thickness of the middle part is 20mm, and the thickness of the rectangular recessed groove 6 of the component is 15mm. When the component is made, 4 reserved holes 7 with a diameter of 4mm are reserved to facilitate the later fixing of high-strength bolts 3. The protective layer thickness of the reinforced concrete beam 4 is 25mm. Before reinforcement, the shear span area of ​​the reinforced concrete beam is first roughened with an electric hammer, and the roughening depth is about 5mm to form a roughening groove 5, which can be used to increase the bite force of the interface between the geopolymer component 2 and the reinforced concrete beam 3 during the later reinforcement. After the roughening is completed, 4 bolt holes with a depth of 25mm are drilled in the shear span area of ​​the beam with an electric drill, and the debris in the hole is cleaned with a strong hair dryer. Then, the high-strength bolts 3 are passed through the reserved holes 7 of the composite member, and then epoxy resin is injected into the holes on the beam, and the high-strength bolts 3 are anchored in the bolt holes. Figures 3-5 As shown, the entire composite component is now tightly attached to the shear span area of ​​the reinforced concrete beam 4. Then, the prepared geopolymer mortar is poured into the composite component concave groove 6, and the roughened groove 5 is vibrated with a vibrating instrument to be filled with geopolymer mortar.

[0058] Geopolymer is a three-dimensional mesh aluminosilicate inorganic polymer composed of silicon-oxygen tetrahedron and aluminum-oxygen tetrahedron as the skeleton formed by the activating effect of alkali activator on aluminosilicate raw materials such as slag, fly ash, quartz sand, silica fume and metakaolin. It has high early strength, fast coagulation and hardening, corrosion resistance, high temperature resistance, high ductility, and strong interface bonding ability with concrete structural materials. When geopolymer is used, the number of cracks in the reinforced beam is small, the problem of interface agent aging is effectively solved, the service life of the component is extended, and energy saving and environmental protection are achieved. It has high practical value and promotion value.

[0059] In summary, the utility model provides a FRP grid-geopolymer composite component and a shear-resistant reinforced concrete beam. By placing the FRP grid in the geopolymer, on the one hand, the problem of epoxy resin being easy to age and not resistant to high temperatures can be solved, and the bonding ability with the concrete interface is strong. On the other hand, the wear caused by direct exposure of the FRP grid to the outside world can be effectively avoided. By anchoring with high-strength bolts, the peeling damage of the reinforcement layer can be effectively avoided under the action of mechanical bite force, the utilization rate of the FRP grid can be effectively enhanced, and the shear resistance of the reinforced concrete beam can be greatly improved. At the same time, during the reinforcement process, the composite component uses itself as a reinforcement template, which can avoid the assembly and disassembly of the template and greatly shorten the construction period.

[0060] 1. FRP grid-geopolymer components, FRP grid and geopolymer work together, significantly improving the shear bearing capacity of reinforced concrete beams, while giving full play to the high strength characteristics of FRP; 2. Compared with the surface of the FRP material directly exposed to the reinforced beam, placing the FRP grid in the geopolymer can effectively avoid the wear caused by the FRP grid being directly exposed to the outside world, and overcome the problem of easy aging of interface agents such as epoxy resin. 3. Using FRP grid-geopolymer components and high-strength bolts together to reinforce the shear span of concrete beams can effectively avoid the peeling damage of the reinforcement layer and greatly enhance the shear resistance. 4. When using geopolymer, the number of cracks in the reinforced beam is small, the resource utilization rate is high, energy-saving and environmentally friendly, and the ability to bond with the concrete interface is strong, which prolongs the service life of the component. 5. The ultra-high toughness of the geopolymer can make up for the disadvantage of the low energy consumption of the FRP grid, greatly improving the ductility and energy consumption capacity of the reinforced concrete beam. 6. When the FRP-geopolymer composite component itself reinforces the reinforced concrete beam, it can be used as a mold, which can avoid the disassembly of the template and greatly improve the construction efficiency.

[0061] The utility model combines the advantages of both geopolymer and FRP grid, can significantly improve the ductility and crack control ability of reinforced concrete beams, greatly improve the bearing capacity, energy dissipation capacity, shear resistance and durability of concrete beams, while taking into account economy, and is worthy of application and promotion.

[0062] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0063] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A FRP grid-geopolymer composite component, characterized in that: The invention comprises an FRP grid and a geopolymer component. A concave groove is arranged on one side surface of the geopolymer component, and the FRP grid is laid in the concave groove.

2. The FRP grid-geopolymer composite member according to claim 1, characterized in that: A boss is arranged on the edge of one side of the geopolymer component to form a concave groove.

3. The FRP grid-geopolymer composite member according to claim 1, characterized in that: The concave groove is rectangular.

4. The FRP grid-geopolymer composite member according to claim 1, characterized in that: A plurality of reserved holes are arranged on the geopolymer component.

5. The FRP grid-geopolymer composite member according to claim 1, characterized in that: The FRP grating includes any one of a BFRP grating, a CFRP grating, and a GFRP grating.

6. The FRP grid-geopolymer composite member according to claim 1, characterized in that: The thickness of FRP grille is 1~3mm.

7. The FRP grid-geopolymer composite member according to claim 1, characterized in that: The depth of the concave groove is 1 / 2 to 1 / 3 of the total thickness of the geopolymer component.

8. A shear-resistant reinforced concrete beam, characterized in that: The invention comprises a reinforced concrete beam and an FRP grid-geopolymer composite component as claimed in any one of claims 1 to 7, wherein the FRP grid-geopolymer composite component is arranged on the front and rear side surfaces of the reinforced concrete beam and anchored on the reinforced concrete beam, the recessed groove is arranged adjacent to the reinforced concrete beam, and the space enclosed by the recessed groove and the reinforced concrete beam is filled with geopolymer mortar.

9. The shear-resistant reinforced concrete beam according to claim 8, characterized in that: The FRP grid-geopolymer composite components are anchored in the shear span area of ​​the reinforced concrete beam by high-strength bolts.

10. The shear-resistant reinforced concrete beam according to claim 8, characterized in that: A roughening groove is arranged on one side surface of the reinforced concrete beam in contact with the FRP grid-geopolymer composite component, and the roughening groove is arranged within the range of the concave groove.

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