Shock insulation support

Abstract

A shock insulation support relates to the technical field of building shock insulation, the support is of a rectangular multi-layer structure with cross sections different in length and width, the support comprises an internal structure layer, the internal structure layer comprises rubber layers and plastic plate layers which are stacked alternately, the number of the rubber layers is larger than that of the plastic plate layers, and the single-layer thickness of the rubber layers is larger than that of the plastic plate layers. According to the support, the structure that the rubber layers and the plastic plate layers are alternately stacked is adopted, traditional steel plates are replaced with the plastic plate layers, the weight of the support is remarkably reduced, and therefore the transportation and construction convenience is improved. Wherein the rubber layer provides enough vertical rigidity and horizontal deformability, and the plastic plate layer ensures the tensile strength and durability of the support, so that the support can still keep good shock insulation performance while the weight is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of building seismic isolation, in particular to a seismic isolation support. Background Art

[0002] Most traditional seismic isolation bearings use laminated steel plate rubber bearings, and their structure is usually composed of multiple layers of rubber and thin steel plates alternately stacked. Although this design can provide good vertical stiffness and a certain horizontal deformation capacity, the use of steel plates causes the overall weight of the bearing to be heavy, which brings many inconveniences to transportation and construction. For example, Chinese patent document CN209585290U discloses a laminated rubber bearing, including a rectangular steel plate cavity, lead core rubber, an upper steel plate, a lower steel plate, an SMA connecting rod, an SMA nut and a fastening bolt. The bearing combines shape memory alloy (SMA) to improve the tensile strength and shock absorption effect of the bearing. However, this solution still relies on steel plates as reinforcing materials, resulting in excessive weight of the bearing. Summary of the invention

[0003] The present invention aims to provide a novel seismic isolation bearing, which reduces the weight of the bearing by optimizing material combination and structural design while maintaining good seismic isolation performance, thereby improving the convenience of transportation and construction.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a seismic isolation bearing, which is a rectangular multi-layer structure with different lengths and widths in cross-section, including an internal structural layer, and the internal structural layer includes alternately stacked rubber layers and plastic plate layers, the number of rubber layers is greater than the number of plastic plate layers, and the single-layer thickness of the rubber layer is greater than the single-layer thickness of the plastic plate layer.

[0005] Furthermore, the cross-sectional aspect ratio of the support is not less than 2:1 (eg 2:1).

[0006] Furthermore, the cross-sectional area of ​​the support is 0.1152m 2 Integer multiples (e.g. 0.1152m 2 ).

[0007] Furthermore, the ratio of the single-layer thickness of the rubber layer to the single-layer thickness of the plastic plate layer is not less than 4:3 (for example, 4:3).

[0008] Furthermore, the total height of the support does not exceed 1 / 2 of the length of the long side of its cross section, and does not exceed 1 / 4 of the length of the short side.

[0009] Furthermore, the plastic board layer is made of a composite material, and the composite material includes glass fiber (such as glass fiber woven cloth) and unsaturated polyester.

[0010] Furthermore, the support also includes an upper sealing plate located at the upper end of the internal structure layer and a lower sealing plate located at the lower end of the internal structure layer, and the upper sealing plate and the lower sealing plate have the same thickness.

[0011] Furthermore, the support also includes an upper protective layer, a lower protective layer and surrounding protective layers that surround the internal structural layer, the upper sealing plate and the lower sealing plate. The thickness of all protective layers is the same and is greater than the single layer thickness of the rubber layer and less than the thickness of the upper sealing plate and the lower sealing plate.

[0012] Traditional laminated steel plate rubber bearings use steel plates as reinforcement materials, resulting in a heavy overall weight of the bearing, which is inconvenient to transport and construct. In contrast, the present invention adopts a structure in which rubber layers and plastic plate layers are alternately stacked, and the plastic plate layers replace the traditional steel plates, which significantly reduces the weight of the bearing, thereby improving the convenience of transportation and construction. Among them, the rubber layer provides sufficient vertical stiffness and horizontal deformation capacity, while the plastic plate layer ensures the tensile strength and durability of the bearing, so that the bearing can maintain good seismic isolation performance while reducing weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a cross-sectional view of the seismic isolation bearing;

[0014] Figure 2 It is a three-dimensional diagram of the seismic isolation bearing;

[0015] Figure 3 The curve diagram of the relationship between the vertical force and displacement of the seismic isolation bearing, where (a) is 5MPa surface pressure and (b) is 10MPa surface pressure;

[0016] Figure 4 It is the horizontal force-displacement curve of the seismic isolation bearing, where (a-1) is the X-direction of the 1# bearing, (a-2) is the Y-direction of the 1# bearing, (b-1) is the X-direction of the 2# bearing, and (b-2) is the Y-direction of the 2# bearing;

[0017] Figure 5 The horizontal force-horizontal displacement curve of the seismic isolation bearing under 5MPa surface pressure, where (a) is the bearing X direction and (b) is the bearing Y direction;

[0018] Figure 6 Schematic diagram of shear strain correlation of horizontal stiffness of seismic isolation bearing;

[0019] Figure 7 It is the horizontal force-horizontal displacement curve of the seismic isolation bearing γ=±100%, where (a) is the bearing X direction and (b) is the bearing Y direction;

[0020] Figure 8 Schematic diagram of the compressive stress correlation of the horizontal stiffness of the isolation bearing.

[0021] In the figure:

[0022] 1——Rubber layer 2——Plastic board layer 3——Upper sealing board

[0023] 4——Lower sealing plate 5——Upper protective layer 6——Lower protective layer

[0024] 7-Protective layer all around. DETAILED DESCRIPTION

[0025] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the embodiments are not intended to limit the present invention.

[0026] like Figure 1 , 2 As shown, this embodiment provides a new type of seismic isolation bearing, which is a rectangular multi-layer structure with different lengths and widths in the cross section. The bearing includes an internal structural layer, which includes alternately stacked rubber layers 1 and plastic plate layers 2, the number of rubber layers 1 is greater than the number of plastic plate layers 2, and the single layer thickness of the rubber layer 1 is greater than the single layer thickness of the plastic plate layer 2. This design gives the bearing a lightweight characteristic, making it particularly suitable for seismic isolation needs of buildings in rural areas.

[0027] In this embodiment, the support adopts a structure in which a rubber layer 1 and a plastic plate layer 2 are alternately stacked, and the number of rubber layers 1 is more than that of the plastic plate layer 2 and the thickness of a single layer is larger. The high elasticity of the rubber layer 1 can effectively isolate seismic energy, reduce the impact of earthquakes on village and town buildings, protect the building structure from serious damage, and ensure the safety of life and property of residents. The plastic plate layer 2 provides the necessary rigidity and bearing capacity to ensure that the support stably supports the building structure in daily use, while limiting the excessive deformation of the rubber layer 1 to avoid failure of the support due to excessive deformation. This design not only ensures the seismic isolation effect, but also reasonably controls the manufacturing cost of the support, making it more suitable for the actual situation of limited economic conditions in rural areas, with high cost performance, and convenient for wide promotion and application. The cross-sectional aspect ratio of the support is not less than 2:1, which can better adapt to the diverse structural forms and stress characteristics of village and town buildings, and can effectively play a seismic isolation role whether it is arranged along the longitudinal or transverse direction of the building. At the same time, this aspect ratio design helps the support to remain stable under uneven force, reduce the damage to the support caused by local deformation of the building, and enhance the overall seismic stability of village and town buildings. In addition, the cross-sectional area of ​​the support is designed to be 0.1152m 2The ratio of the single-layer thickness of the rubber layer 1 to the single-layer thickness of the plastic sheet layer 2 is not less than 4:3. This design ensures the stability and bearing capacity of the bearing while optimizing the seismic isolation effect. The thicker rubber layer 1 can dissipate seismic energy more fully and reduce the damage to the building structure caused by the earthquake; while the plastic sheet layer 2 of appropriate thickness avoids excessive deformation and performance degradation caused by the excessive thickness of the rubber layer 1, ensuring that the bearing maintains a good working condition during the long-term use of village and town buildings and adapts to the use characteristics and environmental conditions of village and town areas.

[0028] In this embodiment, the upper sealing plate 3 and the lower sealing plate 4 of the support are located at the upper and lower ends of the internal structural layer, which can effectively protect the internal structural layer from the influence of the external environment, such as wind, rain, sun, etc., extend the service life of the support, and reduce the maintenance cost of village and town buildings. At the same time, the sealing plate can also provide a certain bearing capacity, enhance the overall stability of the support, ensure that the support maintains good working performance in the long-term use of village and town buildings, and ensure the safety and stability of the building. In addition, the support is also provided with an upper protective layer 5, a lower protective layer 6 and a surrounding protective layer 7 surrounding the internal structural layer, the upper sealing plate 3 and the lower sealing plate 4. The thickness of these protective layers is the same and is greater than the single layer thickness of the rubber layer 1 and less than the thickness of the upper sealing plate 3 and the lower sealing plate 4. The protective layer further enhances the protective performance of the support, prevents the internal structural layer from being damaged by collision, wear and tear, and improves the reliability and durability of the support. Its buffering effect can reduce the impact of external impact on the internal structure of the support, enable the support to better adapt to the use environment of village and town buildings, ensure the long-term and stable performance of seismic isolation performance, and ensure the safety of village and town buildings when an earthquake occurs.

[0029] In this embodiment, the total height of the support does not exceed 1 / 2 of the length of the long side of its cross-section, and does not exceed 1 / 4 of the length of the short side. This height limit is of great significance in the seismic isolation of buildings in rural areas. First, most rural buildings are low-rise structures with limited bearing capacity. A reasonable support height can ensure that it matches the size of the building structure and avoid structural instability or installation difficulties caused by excessively high supports. Secondly, optimizing the support height can effectively control the transmission path and deformation range of seismic energy, so that the support can better play a seismic isolation role under the action of an earthquake and reduce the damage to the building structure caused by the earthquake. In addition, a lower support height can reduce material consumption, reduce manufacturing costs, and improve the feasibility of the application of seismic isolation technology in rural buildings, making it more in line with the economic conditions of rural areas.

[0030] In this embodiment, the plastic plate layer 2 is made of a composite material, which includes glass fiber (such as glass fiber gingham cloth) and unsaturated polyester. This material combination has significant advantages in seismic isolation bearings. Glass fiber has the characteristics of high strength and low density, which can significantly improve the mechanical strength and rigidity of the plastic plate layer 2, so that it remains stable during load-bearing and deformation. Unsaturated polyester resin provides good chemical corrosion resistance and electrical properties, and the curing method is flexible and fast, which can meet the use requirements of seismic isolation bearings. Compared with traditional steel plate materials, this composite material has a lower density, which can effectively reduce the overall weight of the bearing, facilitate transportation and installation, and is particularly suitable for relatively simple construction conditions in rural areas. In addition, the corrosion resistance and anti-aging properties of the composite material are better than those of traditional materials, which can extend the service life of the bearing, reduce maintenance costs, and adapt to the complexity of the natural environment in rural areas. This composite material combines the high strength of glass fiber and the excellent properties of unsaturated polyester. It can provide sufficient bearing capacity and stability while ensuring seismic isolation performance, and is an ideal material for seismic isolation bearings.

[0031] In addition, the seismic isolation support of this embodiment can be processed and formed by using hot vulcanization technology.

[0032] In order to verify the seismic isolation performance of the seismic isolation support of this embodiment, the following test was conducted. The plane size of the seismic isolation support used in the test is 240mm×480mm, and the total height is 111mm. Among them, the rubber layer 1 has 12 layers, each layer is 4mm thick, and the shear modulus is 0.392kN / mm 2 The G4 type rubber; the plastic plate layer 2 has 11 layers, each layer is 3 mm thick. In addition, the thickness of the upper sealing plate 3 and the lower sealing plate 4 are both 10 mm, and the thickness of the upper protective layer 5, the lower protective layer 6 and the surrounding protective layer 7 are all 5 mm.

[0033] The test device uses a seismic isolation bearing compression shear test machine, with a vertical force of 10,000 kN, using a 10,000 kN static jack (pressure 10,000 kN), and a stroke of 350 mm. The horizontal force is ±500 kN, using a servo actuator, and the stroke is ±200 mm.

[0034] 1. Vertical compression mechanical properties test

[0035] When conducting the compression test, the vertical load corresponding to the axial compressive stress (1±30%)σ0 was selected and repeated loading was performed 4 times. The vertical mechanical performance test results of the bearing under axial compressive stress of 5MPa and 10MPa are shown in Figure 3The test results show that when the axial compressive stress is 5MPa, the vertical stiffness of the bearing is 652.75kN / mm; and when the axial compressive stress is 10MPa, the vertical stiffness is 779kN / mm. The results show that the seismic isolation bearing has a large bearing area and exhibits good vertical stiffness performance under different axial compressive stresses.

[0036] 2. Horizontal shear mechanical properties test

[0037] During the horizontal shear test, the axial compressive stress σ0 = 5MPa, the shear strain γ = ±100%, the loading frequency f = 0.05Hz, the horizontal sinusoidal loading, and the loading was repeated 4 times. The horizontal shear test was performed on the two seismic isolation bearing specimens (1# bearing and 2# bearing) in the X and Y directions respectively, and the horizontal stiffness of the bearing in the X and Y directions was calculated using the third loading result. The test results are shown in Figure 4 As shown. Figure 4 In the graph, the vertical axis (y-axis) represents force (f) and the horizontal axis (x-axis) represents displacement (u).

[0038] Under the basic surface pressure of 5MPa, the test values ​​and theoretical values ​​of the horizontal stiffness of the X-direction and Y-direction of the seismic isolation bearing are shown in Table 1. The calculation formula of the theoretical value of the horizontal stiffness in the table is:

[0039]

[0040] In the formula, G is the shear modulus of the rubber, A is the cross-sectional area of ​​the support, and T r is the total thickness of the rubber layer.

[0041] Comparing the test value with the theoretical value, it can be seen that the maximum difference between the theoretical value and the test value of the horizontal stiffness of the isolation bearing is 12%, and the minimum difference is 5%. According to the requirements for classification of allowable deviations according to shear performance in the specification "GB20688.3-2006 Rubber Bearings-Part 3: Building Rubber Isolation Bearings", the maximum allowable difference of the same batch of bearings is ±20%. Therefore, the isolation bearing basically meets the maximum allowable deviation between the theoretical calculated stiffness and the test stiffness.

[0042] It can also be seen from Table 1 that the stiffness of the two bearing specimens in the X and Y directions differ by 1.77% and 6.44% respectively. It can be seen that the difference in the horizontal stiffness of the bearing in the two directions is small and both are within the acceptable range.

[0043] Table 1 Horizontal stiffness of seismic isolation bearings

[0044]

[0045] 3. Correlation analysis of horizontal stiffness

[0046] Under the action of 5Mpa axial compressive stress, the hysteresis curves of horizontal force and horizontal displacement of the support specimen in the X-direction and Y-direction at horizontal shear strains of ±100%, ±200%, and ±250% were tested respectively. The test results are shown in Figure 5 According to the hysteresis curve, the correlation between the horizontal stiffness and horizontal shear strain of the support in the X and Y directions is obtained. The results are shown in Figure 6 The results show that under the same axial compressive stress, the horizontal stiffness of the support in the X-direction and Y-direction decreases with the increase of horizontal shear strain, and the shear strain correlation of the horizontal stiffness in the X-direction and Y-direction of the support shows approximately linear characteristics.

[0047] Depend on Figure 6 It can be seen that the horizontal stiffness of the seismic isolation bearing degrades to a certain extent with the increase of shear strain. For example, the horizontal stiffness of the bearing degrades to 78.75% of the shear strain of 100% at 250% shear strain in the X direction, and to 85.02% of the shear strain of 100% at 250% shear strain in the Y direction. It can be seen that the stiffness degradation of the bearing in the X direction is more obvious, which also shows that the ability to resist horizontal stiffness degradation in the long side direction is better than that in the short side direction. Therefore, increasing the size of the seismic isolation bearing in the shear direction helps to improve the ability of the bearing to resist horizontal stiffness degradation in this direction.

[0048] The compression shear test was carried out on the support in the X and Y directions under different compressive stresses. The vertical compressive stress was 5MPa, 10MPa, and 15MPa respectively. The horizontal shear strain was ±100%. The hysteresis relationship between the horizontal force and displacement of the support in the X and Y directions was measured. The results are as follows: Figure 7 The relationship between the horizontal stiffness and compressive stress of the support in the X and Y directions obtained from the hysteresis curve is shown in Figure 8 As shown in the figure, it can be seen that as the compressive stress of the support increases, the area of ​​the hysteresis loop gradually increases. At the same time, the horizontal stiffness of the support decreases as the compressive stress increases, and the difference between the horizontal stiffness in the X direction and the Y direction continues to increase.

[0049] Depend on Figure 8 It can be seen that the horizontal stiffness of the bearing in the X direction degrades to 75.11% of that at 5MPa under 15MPa compressive stress, and the horizontal stiffness in the Y direction degrades to 94.78% of that at 5MPa. It can be seen that the degradation of the horizontal stiffness of the seismic isolation bearing is limited as the compressive stress increases. Therefore, increasing the plane size of the seismic isolation bearing can improve the bearing's ability to resist the degradation of horizontal stiffness under large surface pressure.

[0050] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present technical solution is within the protection scope of the present invention.

[0051] Finally, it should be emphasized that in order to allow ordinary technicians in the field to more easily understand the improvements of the present invention over the prior art, some descriptions of the present invention have been simplified, and for the sake of clarity, some other elements are omitted in this application document. Those skilled in the art should realize that these omitted elements may also constitute the content of the present invention.

Claims

1. A seismic isolation bearing, characterized in that: The support is a rectangular multilayer structure with different cross-sectional lengths and widths, comprising an internal structural layer, wherein the internal structural layer comprises rubber layers (1) and plastic plate layers (2) stacked alternately, the number of rubber layers (1) being greater than the number of plastic plate layers (2), and the single-layer thickness of the rubber layer (1) being greater than the single-layer thickness of the plastic plate layer (2).

2. The seismic isolation support according to claim 1, characterized in that: The cross-sectional aspect ratio of the support is not less than 2:

1.

3. The seismic isolation support according to claim 1, characterized in that: The cross-sectional area of ​​the support is an integer multiple of 0.1152 m².

4. The seismic isolation support according to claim 1, characterized in that: The ratio of the single-layer thickness of the rubber layer (1) to the single-layer thickness of the plastic plate layer (2) is not less than 4:

3.

5. The seismic isolation support according to claim 1, characterized in that: The total height of the support does not exceed 1 / 2 of the length of the long side of its cross section, and does not exceed 1 / 4 of the length of the short side.

6. The seismic isolation support according to claim 1, characterized in that: The plastic plate layer (2) is made of a composite material, wherein the composite material comprises glass fiber and unsaturated polyester.

7. The seismic isolation support according to claim 1, characterized in that: It also comprises an upper sealing plate (3) located at the upper end of the internal structural layer and a lower sealing plate (4) located at the lower end of the internal structural layer, wherein the upper sealing plate (3) and the lower sealing plate (4) have the same thickness.

8. The seismic isolation support according to claim 7, characterized in that: It also includes an upper protective layer (5), a lower protective layer (6) and surrounding protective layers (7) that surround the internal structural layer, the upper sealing plate (3) and the lower sealing plate (4); the thickness of all protective layers is the same and is greater than the single layer thickness of the rubber layer (1) and less than the thickness of the upper sealing plate (3) and the lower sealing plate (4).

Images