A multi-level impact-resistant reinforcement system for H-shaped steel columns

Abstract

The present invention belongs to the field of structural impact protection and relates to a multi-stage impact-resistant reinforcement system for H-shaped steel columns, which includes an existing H-shaped steel column, a strengthening device, and a protection device; the existing H-shaped steel column is composed of a structural column, a column base plate, and column bottom bolts; the strengthening device is composed of two tensile welding plates and two L-shaped welding plates, which are divided into two groups and symmetrically arranged on both sides of the web of the structural column; the L-shaped welding plate is welded by a compressive short plate, a side plate, and a buckle; the bottom edge of the side plate is welded to the column base plate, and both side edges of the side plate are welded to the two flanges of the structural column; the bottom edge of the tensile welding plate is welded to the column base plate, and one side edge of the tensile welding plate is welded to the web of the structural column; the protection device is welded or bonded by a C-shaped insertion plate, a number of energy dissipation tubes, and an impact plate. The present invention can meet the requirements of multi-stage impact resistance without occupying the ground area of the existing H-shaped steel column; the present invention is simple and easy to implement, convenient for repair and replacement after damage, and has good economic effects.

Description

Technical Field

[0001] The invention belongs to the field of impact protection of buildings and structural engineering, and also belongs to the field of reinforcement of existing steel structures. Background Art

[0002] Steel structure is a common structural type in cities and industries. With its advantages of fast construction speed, convenient construction and environmental protection, it has been widely used in engineering construction in recent years; for example, automated parking garages, parking sheds, gas stations, etc. However, since the use functions of these buildings are closely related to cars, during service, it is easy to have sudden accidents such as structural columns being hit by vehicles. In order to solve this problem, designers set up anti-collision columns on the front lawn of existing buildings and facilities to prevent vehicles from crashing in at the expense of anti-collision columns; or wrap a layer of outer tube sleeve around the periphery of the structural column to absorb the impact energy to achieve the purpose of reducing the impact force. Although these methods can play a certain role, they all occupy the originally tight urban land without exception. For example, the protection method of setting up anti-collision columns on the front lawn of building facilities not only affects the appearance, but also occupies a large area of ​​the ground; the protection method of wrapping the structural column with a tube sleeve is tantamount to directly increasing the cross-sectional size of the column. The effect is acceptable in the case of low-speed impact, but the thickness of the outer tube needs to be greatly increased to resist high-speed impact, which also occupies the ground area and is extremely uneconomical.

[0003] On the other hand, most protective structures are for concrete structures such as bridge piers. For steel structural columns, especially the commonly used H-section columns, there are few inventions related to their protective reinforcement facilities. At present, this type of steel column has been in service in urban facilities, but it has a significant problem of insufficient impact resistance, and replacing the steel column is unrealistic and uneconomical. Therefore, a reinforcement method is urgently needed to improve the impact resistance of existing H-shaped steel columns and then enhance the robustness of the overall structure to protect people’s lives and property safety. Taking into account the problems that the currently commonly used impact-resistant reinforcement protection measures occupy a large area of ​​the building ground, cannot achieve different levels of performance requirements under low-speed and high-speed impacts, and have poor compatibility with common H-shaped steel columns; it is necessary to propose a multi-level impact-resistant reinforcement system for H-shaped steel columns. Summary of the invention

[0004] The purpose of the present invention is to propose a multi-level impact-resistant reinforcement system for H-shaped steel columns based on the deficiencies of the prior art and in combination with the stress characteristics and failure modes of H-shaped steel columns under impact loads; without occupying the ground area of ​​existing steel columns, it can achieve the following multi-level impact-resistant performance requirements: low-speed impacts will not damage the steel columns, and high-speed impacts will not fail the steel columns; and the reinforcement system is simple and easy to set up, easy to repair and replace after damage, and has good economic effects.

[0005] The solution adopted by the present invention to solve its technical problems is as follows: A multi-level impact-resistant reinforcement system for H-shaped steel columns, including an existing H-shaped steel column, a strengthening device, and a protection device; the existing H-shaped steel column consists of a structural column, a column base plate, and column base bolts; the strengthening device consists of two tensile welding plates and two L-shaped welding plates, which are divided into two groups and symmetrically arranged on both sides of the web of the structural column; the L-shaped welding plate is welded by a compressive short plate, a side plate, and a buckle; the buckle is arranged on the outer side of the back of the side plate; the bottom edge of the side plate is welded to the column base plate, and the two side edges of the side plate are welded to the two flange edges of the structural column; the bottom edge of the tensile welding plate is welded to the column base plate, and the single side edge of the tensile welding plate is welded to the web of the structural column; the protection device is welded or bonded by a C-shaped insertion plate, a number of energy dissipation tubes, and an impact plate; the energy dissipation tubes are arranged between the C-shaped insertion plate and the impact plate; the impact plate faces the impact side of the structural column; the protection device is connected to the L-shaped welding plate by inserting the C-shaped insertion plate into the buckle.

[0006] Preferably, the distance between the top of the strengthening device and the top of the column base plate is 0.8 m - 1 m.

[0007] Preferably, the distance between the center of the protection device and the top of the column base plate is 0.5 m - 0.6 m.

[0008] Preferably, the widths on both sides of the impact plate are flush with the widths of the flange edges of the structural column, and the up-and-down width of the impact plate is 0.25 m - 0.5 m.

[0009] Preferably, the tensile welding plate is arranged close to the flange edge of the impact side of the structural column, and the compressive short plate is arranged close to the non-impact side flange edge.

[0010] Preferably, the energy dissipation tube is filled with at least one high-elastic material selected from rubber, sponge, and foam.

[0011] The function of the present invention is that the protection device and the strengthening device jointly form a reinforcement system combining rigidity and flexibility, achieving "soft on the outside and rigid on the inside"; without increasing the floor area of the existing H-shaped steel column, the reinforcement effect of "no damage to the steel column under low-speed impact and no failure under high-speed impact" can be achieved. In the case of low-speed impact, due to the reasonable stiffness cooperation between the protection device and the strengthening device, the impact energy can be mainly absorbed by the protection device, and the steel column is not damaged. If the protection device is damaged, it can be pulled out through the C-shaped insertion plate and a new protection device can be inserted to realize the reuse of the reinforcement system. In the case of high-speed impact, this reinforcement system enhances the flexural and shear stiffness of the existing H-shaped cross-section steel column, improves the integrity of the cross-section, reduces the local deformation at the impact point of the steel column, and enhances the impact resistance of the steel column. This reinforcement system is simple in setting and convenient to replace, and has good application and popularization value. Brief Description of the Drawings

[0012] Figure 1 is a schematic structural diagram of an embodiment of the present invention;

[0013] Figure 2 For Figure 1 the structural decomposition diagram of the illustrated embodiment;

[0014] Figure 3 For Figure 1 the schematic A-A sectional view of

[0015] Figure 4 For Figure 1 the schematic B-B sectional view of

[0016] Figure 5 For Figure 4 the schematic C-C sectional view of

[0017] Figure 6 is the impact deformation diagram of the steel column without the embodiment of the present invention;

[0018] Figure 7 is the impact deformation diagram of the steel column with the embodiment of the present invention.

[0019] Description of the reference numerals:

[0020] F - Impact side of the structural column; 1 - Existing H-shaped steel column; 2 - Reinforcement device; 3 - Protection device; 101 - Structural column; 102 - Column base plate; 103 - Column bottom bolt; 201 - Tensile welding plate; 202 - L-shaped welding plate; 212 - Compressive short plate; 222 - Side plate; 232 - Buckle; 301 - C-shaped insertion plate; 302 - Energy dissipation pipe; 303 - Impact plate. Detailed implementation manners

[0021] The present invention will be further described below with reference to the drawings and embodiments:

[0022] As Figures 1-5As shown in the figure, this embodiment includes an existing H-shaped steel column 1, a reinforcement device 2, and a protection device 3; the existing H-shaped steel column 1 is composed of a structural column 101, a column base plate 102, and column base bolts 103; the reinforcement device 2 is composed of two tensile welding plates 201 and two L-shaped welding plates 202, which are divided into two groups and symmetrically arranged on both sides of the web of the structural column 101; the L-shaped welding plate 202 is welded and formed by a compression-resistant short plate 212, a side plate 222, and a buckle 232; the buckle 232 is arranged on the outer back side of the side plate 222; the bottom edge of the side plate 222 is welded to the column base plate 102, and both side edges of the side plate 222 are welded to the two flanges of the structural column 101; the bottom edge of the tensile welding plate 201 is welded to the column base plate 102, and one side edge of the tensile welding plate 201 is welded to the web of the structural column 101; the protection device 3 is welded or adhered by a C-shaped insertion plate 301, a number of energy dissipation tubes 302, and an impact plate 303; the energy dissipation tubes 302 are arranged between the C-shaped insertion plate 301 and the impact plate 303; the impact plate 303 faces the impact side of the structural column 101; the protection device 3 is connected to the L-shaped welding plate 202 by inserting the C-shaped insertion plate 301 into the buckle 232; the distance between the top of the reinforcement device 2 and the top of the column base plate 102 is 0.8 m - 1 m; the distance between the center of the protection device 3 and the top of the column base plate 102 is 0.5 m - 0.6 m; the width of both sides of the impact plate 303 is flush with the width of the flange of the structural column 101, and the up and down width of the impact plate 303 is 0.25 m - 0.5 m; the tensile welding plate 201 is arranged close to the impact side flange of the structural column 101, and the compression-resistant short plate 212 is arranged close to the non-impact side flange; at least one high elastic material selected from rubber, sponge, and foam is filled in the energy dissipation tube 302.

[0023] The main function of the protection device 3 is to protect the structural column 101 from damage under low-speed impact; through the energy absorption effect of the energy dissipation tube 302, on the one hand, the impact kinetic energy of the vehicle is consumed, and on the other hand, the magnitude of the impact force is reduced. The main function of the reinforcement device 2 is to prevent the structural column 101 from failing under high-speed impact; by adding ribs to both sides of the structural column 101 through the L-shaped welding plate 202 and the tensile welding plate 201, a double-chamber cross-section is formed, which not only improves the integrity of the cross-section but also greatly enhances the bending resistance and shear resistance of the column cross-section.

[0024] Since the protective device 3 and the reinforcing device 2 form a series stiffness system, in general, if the stiffness of the energy dissipation tube 302 in the protective device 3 is designed to be too large, while the energy dissipation tube 302 undergoes plastic deformation to absorb energy, the structural column 101 will also undergo a certain degree of plastic deformation. Therefore, when designing, on the basis of using the reinforcing device 2 to improve the stiffness of the structural column 101, the stiffness of the energy dissipation tube 302 needs to be reduced as much as possible, and the effect of "soft outside and hard inside" can be achieved through reasonable stiffness matching. At this time, when the structural column 101 is impacted, the outer soft part (protective device 3) deforms and bears energy consumption first, and the structural column 101 undergoes slight deformation; when the deformation of the protective device 3 reaches the limit, the structural column 101 will begin to deform further, and jointly bear the subsequent energy consumption with the inner hard part (reinforcement device 2). Reducing the wall thickness can achieve the effect of reducing the stiffness of the energy dissipation tube 302, but the total energy dissipation capacity of the energy dissipation tube 302 with smaller stiffness will be relatively small. The total energy dissipation capacity of the energy dissipation tube 302 can be increased to compensate for the loss by increasing the length of the energy dissipation tube 302, filling the tube with highly elastic materials, etc. Therefore, it can be seen that by calculating and designing the length, tube wall thickness, and type of filling material of the energy dissipation tube 302, the impact kinetic energy can be absorbed by the protective device 3 and the structural column 101 can be deformed only in the elastic stage in the case of low-speed impact, thereby achieving the purpose of not damaging the steel column in the case of low-speed impact.

[0025] When the protective device 3 is damaged, it can be pulled out through the C-shaped plug plate, and then a new protective device 3 can be inserted to achieve the reuse of the reinforcement system.

[0026] The reinforcing device 2 can continue to ensure the impact resistance of the structural column 101 after the protective device 3 is damaged by the impact, so as to avoid excessive local deformation that causes the structural column 101 to fail completely. The reinforcing device 2 mainly achieves the effect of enhancing the impact resistance of the structural column 101 by increasing the bending and shear stiffness of the cross section and changing the stress characteristics. The improvement of the bending and shear stiffness of the cross section can make the structural column 101 consume more energy under the same displacement. After the reinforcing device 2 is set, the stress characteristics of the structural column 101 under the impact are transformed from the original shear buckling and local buckling deformation energy consumption to overall bending and shear deformation energy consumption. The overall relatively uniform deformation energy consumption disperses the energy consumption position of the structural column 101 and reduces the degree of damage to the structural column 101.

[0027] The following is the mechanical mechanism of the front and rear structural columns 101 under impact load using the H-shaped steel column multi-stage impact-resistant reinforcement system:

[0028] like Figure 6As shown, when this embodiment is not provided, the structural column 101 mainly relies on shear buckling deformation and local buckling deformation to consume impact energy. Among them, the shear stiffness is mainly provided by the web, and the local buckling deformation mainly occurs at the impact location, which is manifested as severe concave bending of the web. This is because the flange of the overhanging part in the H-shaped section belongs to a simply supported plate with one side free and the other three sides. Its free end lacks support and is extremely weak. When impacted, it will deform violently, so that the subsequent impact load at this end cannot be well transmitted to the bottom of the column, resulting in poor cross-sectional bending resistance. Therefore, the impact load is basically transmitted to the bottom of the column through the web support end of the overhanging flange, so the force characteristics mainly show the shear buckling of the web below the impact. This resistance mode is very unfavorable for energy consumption, and the web shear is also prone to local fracture.

[0029] Figure 7 As shown, when this embodiment is set, since the side plate 222 provides support for the flange of the structural column 101, the flange of the overhanging part in the H-shaped cross section is equivalent to a four-sided simply supported plate, and both ends of the flange can transmit force. In addition, due to the wrapping effect of the C-shaped plug plate 301, the integrity of the impacted part is further enhanced, so that the structural column 101 will not have serious local deformation under high-speed impact, especially at this time, the web will no longer be concave.

[0030] In summary, under high-speed impact, after the present embodiment is set, the structural column 101 is transformed into mainly relying on overall bending and shear deformation to jointly consume energy. At this time, the impact side flange of the structural column 101 is tensile, and the non-impact side flange is compressed. The compressive short plate 212 in the tensile welded plate 201 and the L-shaped welded plate 202 in the present embodiment well reduces the tensile and compressive stresses of the flanges on both sides of the structural column 101, further improving the bending stiffness of the structural column 101 and enhancing its impact resistance.

[0031] When reinforcing and installing the existing H-shaped steel column 1, first weld and install the tensile welding plate 201, then weld and install the L-shaped welding plate 202, and finally insert the C-shaped plug plate 301 in the protective device 3 into the buckle 232 on the outside of the L-shaped welding plate 202 to complete the installation of the embodiment of the invention.

Claims

1. A multi - level impact - resistant reinforcement system for H - shaped steel columns, characterized in that: it includes an existing H - shaped steel column, a strengthening device, and a protection device; the existing H - shaped steel column is composed of a structural column, a column base plate, and column base bolts; the strengthening device is composed of two tensile welding plates and two L - shaped welding plates, which are divided into two groups and symmetrically arranged on both sides of the web of the structural column; the L - shaped welding plate is welded by a compressive short plate, a side plate, and a buckle; the buckle is arranged on the outer back side of the side plate; the bottom edge of the side plate is welded to the column base plate, and the two side edges of the side plate are welded to the two flanges of the structural column; the bottom edge of the tensile welding plate is welded to the column base plate, and one side edge of the tensile welding plate is welded to the web of the structural column; the protection device is welded or bonded by a C - shaped insertion plate, a number of energy - dissipating tubes, and an impact plate; the energy - dissipating tubes are arranged between the C - shaped insertion plate and the impact plate; the impact plate faces the impact side of the structural column; the protection device is connected to the L - shaped welding plate by inserting the C - shaped insertion plate into the buckle.

2. The multi - level impact - resistant reinforcement system for H - shaped steel columns according to claim 1, characterized in that: the distance between the top of the strengthening device and the top of the column base plate is 0.8 m - 1 m.

3. The multi - level impact - resistant reinforcement system for H - shaped steel columns according to claim 1, characterized in that: the distance between the center of the protection device and the top of the column base plate is 0.5 m - 0.6 m.

4. The multi - level impact - resistant reinforcement system for H - shaped steel columns according to claim 1, characterized in that: the widths of both sides of the impact plate are flush with the widths of the flanges of the structural column, and the up - and - down width of the impact plate is 0.25 m - 0.5 m.

5. The multi - level impact - resistant reinforcement system for H - shaped steel columns according to claim 1, characterized in that: the tensile welding plate is arranged close to the flange of the structural column on the impact side, and the compressive short plate is arranged close to the flange of the structural column on the non - impact side.

6. The multi - level impact - resistant reinforcement system for H - shaped steel columns according to claim 1, characterized in that: the energy - dissipating tubes are filled with at least one high - elastic material selected from rubber, sponge, and foam.

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