Buckling-restrained brace structure and buckling-restrained brace structure design method

Abstract

The present application relates to the field of civil engineering technology, and in particular to a buckling-resistant support structure and a design method for a buckling-resistant support structure, which are used to support a main structure. The buckling-resistant support structure includes a core unit, a constraint unit and a connection portion, wherein the core unit extends along a first direction, the constraint unit is sleeved on the outside of the core unit, the connection portion is provided at both ends of the core unit in the first direction, the core unit is connected to the constraint unit via the connection portion, and the shear stiffness of the connection portion is equal to a predetermined stiffness. According to the buckling-resistant support structure and the design method for the buckling-resistant support structure provided in the present application, the strength required for the core unit is effectively reduced, so that the core unit can be made of steel with greater elastic-plasticity, and the vibration energy absorption effect of the buckling-resistant support structure is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of civil engineering technology, and in particular to a buckling-restrained brace structure and a design method for the buckling-restrained brace structure. Background Art

[0002] Earthquakes are extremely destructive and are one of the major natural disasters that threaten human life and property. Energy dissipation and shock absorption technology involves installing energy dissipation devices at specific locations on a structure or designing several non-load-bearing parts of the structure into energy dissipation devices. These devices dissipate or absorb the energy input into the structure by the elastic-plastic hysteresis deformation, thereby preventing damage or collapse of the structure and achieving the purpose of energy dissipation and shock absorption. Buckling-resistance braces are metal yield-type energy dissipation devices. Under normal use / under the influence of small-amplitude vibrations, buckling-resistance braces provide lateral stiffness to the main structure. Under the influence of large-amplitude vibrations, buckling-resistance braces utilize the elastic-plastic properties of their core units to dissipate the energy brought by the earthquake, thereby reducing the damage to the main structure caused by the earthquake.

[0003] However, the elastic-plastic properties of steel typically decrease with increasing strength. To ensure that the buckling restraint (AB) provides sufficient lateral stiffness to the main structure during normal use and low-amplitude vibration, the core unit of the AB is typically constructed from steel with a low yield point to ensure the brace's deformation capacity. However, due to the relatively low strength of the core steel, the elastic-plastic properties of the core unit of existing ABs are poor. Consequently, when the AB is subjected to high-amplitude vibration, the AB is not able to absorb the vibration energy effectively. Summary of the Invention

[0004] The purpose of the present application is to provide a buckling-resistance brace structure and a design method for the buckling-resistance brace structure, so as to solve, to a certain extent, the technical problems existing in the prior art, that is, in order to ensure that the buckling-resistance brace can provide sufficient lateral stiffness to the main structure under normal use and under the influence of vibrations with small amplitudes, the elastic-plastic properties of the core unit of the existing buckling-resistance brace are poor, and when the buckling-resistance brace faces vibrations with large amplitudes, the buckling-resistance brace has an unsatisfactory absorption effect on vibration energy.

[0005] According to the first aspect of the present application, a buckling-resistance support structure is provided for supporting a main structure, comprising a core unit, a constraint unit and a connecting portion, wherein the core unit extends along a first direction, the constraint unit is sleeved on the outside of the core unit, and the connecting portion is arranged at both ends of the core unit in the first direction, the core unit is connected to the constraint unit via the connecting portion, and the shear stiffness of the connecting portion is equal to a predetermined stiffness, so that when the total deformation of the core unit along the first direction exceeds the expected displacement, the connecting portion can be sheared off.

[0006] Preferably, the number of the connecting parts is n, and the lateral stiffness of the main structure in the first direction that the buckling-resistance brace structure needs to provide is K e , the stiffness of the core unit in the first direction is K1, and the stiffness of the constraint unit in the first direction is K2;

[0007] Wherein, the predetermined stiffness

[0008] Preferably, the core unit is made of negative Poisson's ratio steel, and the constraint unit is made of ultra-high performance concrete.

[0009] Preferably, the cross section of the core unit obtained by cutting it along a plane perpendicular to the first direction is a rectangle, and the width-to-thickness ratio of the rectangle is 5 to 10;

[0010] The ultimate strength of the core unit is greater than or equal to 800 MPa, and the elongation of the core unit is greater than or equal to 40%;

[0011] The compressive strength of the constraint unit is greater than or equal to 120 MPa, the tensile strength of the constraint unit is greater than or equal to 10 MPa, and the ultimate tensile strain of the constraint unit is greater than or equal to 2000 με.

[0012] Preferably, the constraint unit includes two constraint parts, each of the constraint parts includes a fitting surface and a groove, the groove is concave from the fitting surface to the interior of the constraint part, and when the two constraint parts are in a state of being engaged with each other along the second direction, the fitting surfaces of the two constraint parts fit together, so that the grooves of the two constraint parts enclose and form an installation channel that passes through the constraint unit along the first direction, the core unit passes through the installation channel, and the second direction is the thickness direction of the core unit;

[0013] The buckling-resistance support structure further includes a hoop portion, which is arranged on the outside of the two restraint portions when the two restraint portions are in a state of being buckled with each other.

[0014] Preferably, the constraint unit further includes:

[0015] an elastic close-fitting layer, wherein when the two restraining parts are in a state of being buckled with each other, the contact surfaces of the two restraining parts are contacted via the elastic close-fitting layer;

[0016] The spacer layer is arranged between the inner wall of the placement channel and the core unit to reduce the friction between the core unit and the constraint unit.

[0017] Preferably, the elastic close-fitting layer is made of elastic material, and the thickness of the elastic close-fitting layer is 2 to 3 mm;

[0018] The spacer layer is made of a non-adhesive material and has a thickness of 2 to 3 mm;

[0019] The volumetric hoop ratio of the hoop portion is greater than or equal to 2%.

[0020] Preferably, the connecting portion is a bolt, the bolt extends along the second direction, a portion of the bolt is embedded in the constraint unit, and a depth of the bolt embedded in the constraint unit in the second direction is greater than or equal to three times the nominal diameter of the bolt.

[0021] According to a second aspect of the present application, a design method for a buckling-resistance brace structure is provided, comprising the buckling-resistance brace structure described in any of the above technical solutions. Thus, the method has all the beneficial technical effects of the buckling-resistance brace structure, which will not be described in detail herein.

[0022] The design method of the buckling-resistance brace structure comprises the following steps:

[0023] Iterative calculation determines the preset value, and according to the shock absorption target of the main structure, the support length L of the anti-buckling brace structure and the initial stiffness K of the anti-buckling brace structure are determined by iterative calculation. e and the design bearing capacity P of the buckling-restrained brace structure y ;

[0024] Selecting parameters of the core unit and the constraint unit;

[0025] Evaluate the stability of the buckling-resistance brace structure, calculate the elastic modulus E1 and the bending moment of inertia I1 of the core unit based on the parameters of the core unit, calculate the elastic modulus E2 and the bending moment of inertia I2 of the constraint unit based on the parameters of the constraint unit, determine the calculation length coefficient μ considering the constraint conditions at both ends of the support, and determine the connection load P of the buckling-resistance brace structure that causes support instability. cr,g Is it greater than twice the design bearing capacity of the buckling-restrained brace structure, wherein:

[0026] Preferably, if the connection load P of the buckling-resistance brace structure fails cr,g If the load is less than or equal to twice the design bearing capacity of the buckling-restrained brace, the parameters of the core unit and the constraint unit are adjusted, and the step of evaluating the stability of the buckling-restrained brace is repeated until the connection load P of the buckling-restrained brace causes instability. cr,g Greater than twice the design bearing capacity of the buckling-restrained brace structure;

[0027] When the support of the buckling-restrained brace structure fails, the connection load Pcr,g When the load capacity is greater than twice the design load-bearing capacity of the buckling-restrained brace structure, the lateral stiffness K that the buckling-restrained brace needs to provide to the main structure in the first direction is determined based on the selected parameters of the core unit and the constraint unit. e The stiffness of the core unit in the first direction is K1, and the stiffness of the constraint unit in the first direction is K2. By calculating the predetermined stiffness To determine the diameter of the connecting portion.

[0028] Preferably, the length of the connecting portion is determined according to the diameter of the connecting portion, so that the length of the connecting portion is greater than or equal to three times the diameter of the connecting portion.

[0029] Preferably, the step of selecting parameters of the core unit and the constraint unit includes:

[0030] Determine the cross-sectional area of ​​the core unit, select the material of the core unit, obtain the stiffness setting value f of the core unit, and calculate the stiffness of the core unit by P y =fA i Calculate the cross-sectional area A of the core unit i ;

[0031] Determine the width b of the cross section of the core unit i and thickness, according to the cross-sectional area A of the core unit i , and the width b of the cross section of the core unit i The ratio of the width b of the cross section of the core unit is between 5 and 10. i and thickness;

[0032] Determine the width b of the cross section of the constraint unit o ≥b i +60mm;

[0033] According to the width b of the cross section of the constraint unit o The number n of the connecting portions is determined.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] The buckling-resistance brace structure provided by the present application comprises a structure in which, by providing connecting portions with a shear stiffness equal to a predetermined stiffness at both ends of a core unit, the connecting portions being used to connect the core unit and the constraint unit. When the total deformation of the core unit along a first direction is less than the expected displacement, the core unit and the constraint unit can be connected via the connecting portions, so that the core unit and the constraint unit can jointly provide lateral stiffness to the main structure. When the total deformation of the core unit along the first direction is greater than the expected displacement of the buckling-resistance brace under frequent earthquakes, the connecting portions can be sheared, making the core unit independent of the constraint unit, allowing the core unit to yield in the first direction, thereby absorbing the energy caused by the vibration. In this way, under normal use / vibration with a small amplitude, the constraint unit shares part of the lateral stiffness that the core unit needs to provide to the main structure, effectively reducing the requirement for the cross-sectional size of the core unit, so that the buckling-resistance brace proposed by the present application can simultaneously meet the structure's different requirements for stiffness under frequent earthquakes and energy dissipation capacity under rare earthquakes.

[0036] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 A schematic diagram of the axonometric structure of the buckling-restrained support structure provided in an embodiment of the present application;

[0039] Figure 2 This is a schematic diagram of the axonometric structure of the core unit provided in an embodiment of the present application;

[0040] Figure 3 A schematic diagram of the axonometric structure of the constraint portion provided in an embodiment of the present application;

[0041] Figure 4 A schematic diagram of the axonometric structure of the hoop portion provided in an embodiment of the present application;

[0042] Figure 5 A schematic flow chart of a design method for a buckling-resistance support structure according to an embodiment of the present application.

[0043] Reference numerals:

[0044] 1-core unit; 11-extension part; 12-transition part; 13-joining part; 14-connecting hole; 2-constraint unit; 20-constraint part; 21-fitting surface; 22-groove; 3-connecting part; 4-hoop part; 40-hoop ring; 41-half hoop; 42-jointing part; 43-jointing bolt; 5-rib. DETAILED DESCRIPTION

[0045] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0046] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the present application.

[0047] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0048] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0050] Refer to the following Figures 1 to 5 The present invention describes a buckling-resistance brace structure and a design method of a buckling-resistance brace structure according to some embodiments of the present application.

[0051] See also Figures 1 to 4As shown, an embodiment of the first aspect of the present application provides a buckling-resistance brace structure for supporting a main structure. The buckling-resistance brace structure includes a core unit 1, a constraint unit 2, and a connection portion 3. The core unit 1 extends along a first direction, the constraint unit 2 is sleeved on the outside of the core unit 1, and the connection portions 3 are provided at both ends of the core unit 1 in the first direction. The core unit 1 is connected to the constraint unit 2 via the connection portions 3. The shear stiffness of the connection portion 3 is equal to a predetermined stiffness, so that when the total deformation of the core unit along the first direction exceeds the expected displacement, the connection portion can be sheared.

[0052] According to the above technical features, the buckling-resistance support structure provided by the present application is provided with a connection part 3 with a shear stiffness equal to a predetermined stiffness at both ends of the core unit 1, and the connection part 3 is used to connect the core unit 1 and the constraint unit 2. When the deformation of the core unit 1 is less than the expected deformation (under the action of frequent earthquakes), the core unit 1 and the constraint unit 2 can be connected via the connection part 3, so that the core unit 1 and the constraint unit 2 can jointly provide lateral stiffness to the main structure; when the deformation of the core unit 1 reaches the expected deformation (under the action of rare earthquakes), the connection part 3 can be sheared off, so that the core unit 1 is independent of the constraint unit 2, and the core unit 1 can The core unit 1 can be deformed relative to the constraint unit 2 in the first direction, thereby enabling the core unit 1 to absorb the energy brought by the vibration. In this way, under normal use / vibration with a small amplitude, the constraint unit 2 shares part of the lateral stiffness that the core unit 1 needs to provide to the main structure, effectively reducing the strength required by the core unit 1, so that the core unit 1 can be made of steel with greater elastic-plasticity, effectively improving the absorption effect of the anti-buckling support structure on vibration energy, and enabling the anti-buckling support structure to better take into account both normal use / vibration with a small amplitude and vibration with a large amplitude.

[0053] See also Figures 1 to 4 The direction shown by F1 in the figure can be an example of a first direction, the direction shown by F2 in the figure can be an example of a second direction, and the direction shown by F3 in the figure can be an example of a third direction. Preferably, any two of the first direction, the second direction, and the third direction are perpendicular to each other, wherein the first direction can be the length direction of the core unit 1, the second direction can be the thickness direction of the core unit 1, and the third direction can be the width direction of the core unit 1.

[0054] Preferably, the predetermined stiffness Wherein, n is the number of connecting parts 3; K eThe buckling-resistance brace structure needs to provide the main structure with lateral stiffness in the first direction; K1 is the stiffness of the core unit 1 in the first direction; K2 is the stiffness of the constraint unit 2 in the first direction, so that the additional stiffness K provided by the buckling-resistance brace to the main structure in multiple earthquakes can be guaranteed. e The requirements of the structure are met, and at the same time, when the deformation of the core unit reaches the expected deformation (rare earthquake action), the shear connector can shear failure, so that the main function of the buckling restraint brace is changed from providing lateral stiffness for the structure to yielding and absorbing earthquake energy.

[0055] In an embodiment, Figure 1 and Figure 2 As shown, the core unit 1 may be a meta steel with negative Poisson's ratio effect (NPR steel for short), because NPR steel has higher strength and ductility.

[0056] In addition, for buckling-resistance braces that require greater energy consumption, the cross-sectional dimensions of the core unit 1 are generally larger, which will not only cause a large consumption of resources and energy, but also result in a large deadweight of a single buckling-resistance brace, resulting in higher costs for its transportation, hoisting, and on-site installation. The core unit 1 of the buckling-resistance brace structure provided in the present application is made of NPR steel. Compared with the Q235 steel commonly used as the core unit 1 in the prior art, the strength and ductility of NPR steel are 1.8 and 2.3 of those of Q235 steel, respectively, and NPR steel will undergo slight volume expansion when plastically deformed, which can effectively overcome the diameter shrinkage phenomenon of steel. The energy consumption capacity of NPR steel of the same cross-sectional dimensions is about 3.6 times that of Q235 steel. Therefore, the use of NPR steel in the core unit 1 will effectively reduce the cross-sectional dimensions of the buckling-resistance brace core unit 1, thereby reducing the cross-sectional dimensions and deadweight of the entire buckling-resistance brace.

[0057] Preferably, the ultimate strength of the core unit 1 can be greater than or equal to 800 MPa, and the elongation of the core unit 1 can be greater than or equal to 40%. Usually, the ultimate strength of the NPR steel can reach 880 MPa, and its uniform elongation can reach 55.3%. In this way, the NPR steel can meet the ultimate strength and elongation requirements of the core unit 1. However, it is not limited to this. As long as the ultimate strength and elongation requirements of the core unit 1 can be met, the core unit 1 can also be other materials.

[0058] Preferably, if Figure 1 and Figure 2 As shown, the core unit 1 is a plate. In other words, the cross section of the core unit 1 obtained by cutting it along a plane perpendicular to the first direction is rectangular.

[0059] Preferably, the width-to-thickness ratio of the rectangle may be 5 to 10 to ensure the elastic-plastic properties of the NPR steel.

[0060] like Figure 1 and Figure 2 As shown, the plate surface is defined by a first direction and a third direction.

[0061] Preferably, if Figure 1 and Figure 2 As shown, the core unit 1 may include an extension portion 11 and a connecting portion 13 . The extension portion 11 extends along a first direction. The connecting portions 13 are respectively provided at both ends of the extension portion 11 for connecting the main structure.

[0062] Preferably, if Figure 1 and Figure 2 As shown, in the third direction, the width of the connecting portion 13 is greater than the width of the extending portion 11 , so as to increase the contact area between the core unit 1 and the main structure.

[0063] Alternatively, as Figure 1 and Figure 2 As shown, the connecting portion 13 may further include a plurality of connecting holes 14 penetrating the connecting portion 13 to improve the connection stability between the connecting portion 13 and the main structure.

[0064] Furthermore, if Figure 1 As shown, the core unit 1 may further include ribs 5, which are arranged on both sides of the joint 13 in the second direction, and the ribs 5 are arranged perpendicular to the joint 13 to further improve the connection stability between the joint 13 and the main structure.

[0065] Preferably, if Figure 1 and Figure 2 As shown, the core unit 1 may further include a transition portion 12, which is provided between the extension portion 11 and the coupling portion 13 to connect the extension portion 11 and the coupling portion 13. In the first direction, the width of the transition portion 12 gradually increases from the extension portion 11 to the coupling portion 13.

[0066] Preferably, the extending portion 11 , the transition portion 12 and the connecting portion 13 are integrally formed.

[0067] like Figure 1 As shown, when the constraint unit 2 is sleeved on the outside of the core unit 1 , the coupling portion 13 of the core unit 1 is exposed to the outside of the constraint unit 2 for connection with the main structure.

[0068] Preferably, if Figure 1As shown, the above-mentioned connecting portion 3 is connected to the core unit 1 via the transition portion 12. On the one hand, the width of the transition portion 12 is larger than that of the extension portion 11, and there is enough space to set the upper connecting portion 3; on the other hand, the transition portion 12 is close to the bonding portion 13, so that the transition portion 12 is highly sensitive to stress and deformation, effectively ensuring that the connecting portion 3 is cut off in a timely manner.

[0069] In an embodiment, preferably, the constraint unit 2 can be ultra-high performance concrete (UHPC). Relevant research shows that the chloride ion penetration resistance of UHPC material is 55 times that of ordinary concrete and 30 times that of high-performance concrete, and there is no risk of freeze-thaw spalling. The constraint unit 2 of the buckling-resistance brace structure provided by the present application adopts UHPC. Compared with the buckling-resistance brace of the peripheral unit adopting steel, steel tube concrete or ordinary concrete, it can effectively improve the durability of the buckling-resistance brace. When it is applied to corrosive service environments such as high salt, high humidity, freezing coupling, wave splashing, scouring, etc., it can greatly improve the service life of the buckling-resistance brace and significantly reduce its maintenance cost.

[0070] Preferably, the compressive strength of the constraint unit 2 is greater than or equal to 120 MPa, the tensile strength of the constraint unit 2 is greater than or equal to 10 MPa, and the ultimate tensile strain of the constraint unit 2 is greater than or equal to 2000 με. On the one hand, it ensures that the constraint unit 2 has sufficient strength to shear off the above-mentioned connecting portion 3; on the other hand, it ensures that the constraint unit 2 has sufficient strength to share the lateral stiffness of the main structure.

[0071] Preferably, if Figure 1 In order to facilitate the illustration of the assembly relationship between the core unit 1 and the constraint unit 2, the constraint unit 2 is shown in perspective in the figure. The constraint unit 2 may include two constraint portions 20, which are engaged with each other along the second direction to enable the core unit 1 to be arranged in the following placement channel. In this way, the constraint unit 2 is sleeved on the outside of the core unit 1 by engaging the two constraint portions 20, so that the constraint unit 2 and the core unit 1 are detachably connected. Once the anti-buckling support structure is damaged by vibration, the damaged part can be repaired and replaced, which effectively improves the maintainability of the anti-buckling support structure and effectively reduces the maintenance cost of the anti-buckling support structure.

[0072] Preferably, if Figure 3 As shown, the constraint portion 20 may include a fitting surface 21 and a groove 22, wherein the groove 22 is recessed from the fitting surface 21 toward the interior of the constraint portion 20. Preferably, when observing the groove 22 along the second direction, the shape of the groove 22 is adapted to the shape of the extension portion 11 and the transition portion 12 of the core unit 1.

[0073] Preferably, the thickness of both side walls of the groove 22 in the third direction is greater than or equal to 30 mm. In this way, on the one hand, the side walls are ensured to have sufficient strength to limit the deformation of the core unit 1 along the third direction; on the other hand, a certain number of fibers are usually distributed in UHPC to ensure the performance of UHPC. The thickness of the side walls is greater than or equal to 30 mm, so that the side walls have sufficient space for distributing the fibers, thereby enabling the UHPC to perform well.

[0074] Preferably, if Figure 1 As shown, when the two constraint parts 20 are in a state of being buckled with each other along the second direction, the fitting surfaces 21 of the two constraint parts 20 fit together, so that the grooves 22 of the two constraint parts 20 are arranged to form an installation channel that passes through the constraint unit 2 along the first direction, and the core unit 1 passes through the installation channel.

[0075] Preferably, not shown, the constraint unit 2 may further include a spacer layer, which is arranged between the inner wall of the placement channel and the core unit 1 to reduce the friction between the core unit 1 and the constraint unit 2, so as to prevent the friction force given to the core unit 1 by the constraint unit 2 from hindering the core unit 1 from deforming along the first direction, thereby affecting the effect of the core unit 1 in absorbing vibration energy.

[0076] Preferably, the number of the above-mentioned spacer layers is two, and the two spacer layers can be respectively arranged on both sides of the core unit 1 in the second direction to respectively reduce the friction force of the two constraint parts 20 on the core unit 1.

[0077] Preferably, the thickness of the spacer layer in the second direction may be 2-3 mm, so as to adapt to the deformation of the core unit 1 in the second direction during the deformation of the core unit 1 .

[0078] Preferably, the spacer layer may be made of a non-adhesive material, such as silicone, polyethylene or latex.

[0079] Preferably, if Figure 1 and Figure 4 As shown, the anti-buckling support structure may further include a hoop portion 4. When the two restraint portions 20 are in a state of being buckled with each other, the hoop portion 4 is hooped on the outside of the two restraint portions 20 to achieve the two restraint portions 20 being hooped on the outside of the core unit 1.

[0080] Preferably, the volumetric clamping ratio of the hoop portion 4 is greater than or equal to 2% to ensure the hoop stability of the hoop portion 4 on the two constraint portions 20. The volumetric clamping ratio of the hoop portion 4 can be understood as the ratio of the volume of the hoop portion 4 to the volume of the constraint unit 2.

[0081] Preferably, if Figure 1 and Figure 4 As shown, the hoop portion 4 may include a plurality of hoop rings 40 spaced apart along the first direction to ensure uniform distribution of the restraining force of the restraining unit 2 on the core unit 1 in the first direction.

[0082] Optionally, two of the multiple hoop rings 40 near the two ends of the constraint unit 2 are defined as end hoop rings, and the distance from any end hoop ring to the end of the constraint unit 2 in which it is located is less than or equal to 50 mm to ensure the constraint stability of the end of the constraint unit 2 on the core unit 1.

[0083] Preferably, the distance between any two adjacent hoop rings 40 in the plurality of hoop rings 40 is less than or equal to 200 mm.

[0084] Preferably, if Figure 4 As shown, any hoop collar 40 may include two half-hoops 41, each half-hoop 41 having a butt joint 42 at both ends in the third direction. The butt joint 42 is defined by both the first direction and the third direction. The two half-hoops 41 can be opened and engaged with each other along the second direction to achieve detachable hoop collar 40.

[0085] Optionally, the hoop collar 40 may further include a docking bolt 43. When the two half hoops 41 are buckled together, the docking portions 42 of the two half hoops 41 are relatively arranged along the second direction relative to either end in the third direction. The above-mentioned docking bolt 43 passes through the docking portions 42 of the two half hoops 41 along the second direction to achieve the fixation of the two half hoops 41, and the degree of tightening of the hoop collar 40 on the constraint unit 2 can be adjusted by adjusting the docking bolt 43.

[0086] Preferably, not shown, the constraint unit 2 may further include an elastic close-fitting layer. When the two constraint parts 20 are in a state of being buckled with each other, the fitting surfaces 21 of the two constraint parts 20 are fitted together via the elastic close-fitting layer. In this way, the tightness of the fitting surfaces 21 of the two constraint parts 20 is effectively ensured to prevent the core unit 1 from slipping out of the above-mentioned placement channel due to the loose fitting of the two constraint parts 20.

[0087] Preferably, the elastic adhesion layer may be made of an elastic material, such as rubber, silicone, etc.

[0088] Preferably, the thickness of the elastic adhesion layer may be 2 to 3 mm;

[0089] In an embodiment, Figure 1 and Figure 2 As shown, the connecting portion 3 may extend along the second direction, pass through the core unit 1 along the second direction, and both ends of the connecting portion 3 may be embedded in the two restraining portions 20 respectively.

[0090] Preferably, the connecting portion 3 can be a bolt

[0091] Preferably, the depth of the pin embedded in the constraining unit 2 in the second direction is greater than or equal to three times the nominal diameter of the pin.

[0092] Preferably, the pegs can be hinged to the core unit 1 .

[0093] Preferably, the above-mentioned pegs can also be fixedly connected to the core unit 1 .

[0094] Preferably, there may be a plurality of the pegs, the plurality of pegs being spaced apart along the third direction, and the wheelbase between any two adjacent pegs is three times the nominal diameter of the pegs.

[0095] The embodiment of the second aspect of the present application further provides a design method for an anti-buckling support structure, which is used to design the anti-buckling support structure described in any of the above embodiments. Therefore, it has all the beneficial technical effects of the anti-buckling support structure and will not be repeated here.

[0096] See also Figure 5 As shown, the design method of the buckling-restrained brace structure includes the following steps:

[0097] S100 Iterative calculation determines the pre-value, and determines the support length L of the buckling-resistance brace structure and the initial stiffness K of the buckling-resistance brace structure according to the shock absorption target of the main structure through iterative calculation. e and the design bearing capacity P of the buckling-restrained brace structure y .

[0098] Optionally, before step S100, the steps of the design method of the anti-buckling brace structure may also include S110 analyzing the vibration characteristics of the main structure under earthquake action and S120 determining the shock absorption target of the main structure. Since steps S110 and S120 are existing technologies in the existing design process of the anti-buckling brace structure, they are not repeated here.

[0099] S200 selects parameters of the core unit 1 and the constraint unit 2.

[0100] Preferably, the step of selecting parameters of the core unit 1 and the constraint unit 2 includes:

[0101] S210 determines the cross-sectional area of ​​the core unit 1, selects the material of the core unit 1, obtains the stiffness setting value f of the core unit 1, and calculates the stiffness of the core unit 1 by P y =fA i Calculate the cross-sectional area A of the core unit 1 i .

[0102] S220 Determine the width b of the cross section of the core unit 1 i and thickness, according to the cross-sectional area A of the core unit 1 i , and the width b of the cross section of the core unit 1 is i The ratio of the width b of the cross section of the core unit 1 is between 5 and 10. i and thickness.

[0103] S230 Determine the width b of the cross section of the constraint unit 2 o ≥b i +60mm.

[0104] S240 is based on the width b of the cross section of the constraint unit 2 o The number n of the connecting parts 3 is determined. Specifically, taking the connecting parts 3 as bolts as an example, the multiple bolts are spaced apart along the third direction, and the wheelbase between any two adjacent bolts is three times the nominal diameter of the bolts.

[0105] S300 evaluates the stability of the buckling-restrained brace structure, calculates the elastic modulus E1 and the bending inertia moment I1 of the core unit 1 based on the parameters of the core unit 1, calculates the elastic modulus E2 and the bending inertia moment I2 of the constraint unit 2 based on the parameters of the constraint unit 2, determines the calculation length coefficient μ considering the constraint conditions at both ends of the support, and determines the connection load P of the buckling-restrained brace structure that causes support instability. cr,g Is it greater than twice the design bearing capacity of the buckling-restrained brace structure, wherein: In this way, the overall stability of the buckling-resistance brace structure is effectively guaranteed, out-of-plane instability damage of the buckling-resistance brace is prevented, and the buckling-resistance brace is prevented from failing to work properly under earthquake action.

[0106] Preferably, step S300 of evaluating the stability of the buckling-restrained brace may further include step S310 of confirming a μ value, confirming the connection mode between the connection portion 3 and the core unit 1. If the connection mode between the connection portion 3 and the core unit 1 is a hinged connection, the μ value may be 1; if the connection mode between the connection portion 3 and the core unit 1 is a fixed connection (e.g., welding), the μ value may be 0.5.

[0107] Optionally, if the connection load P of the buckling-restrained brace fails cr,g If the load P of the core unit 1 and the constraint unit 2 is less than or equal to twice the design bearing capacity of the buckling-restrained brace, the parameters of the core unit 1 and the constraint unit 2 are adjusted, and step S300 is repeated until the connection load P of the buckling-restrained brace is unstable. cr,g Greater than twice the design bearing capacity of the buckling-restrained brace structure;

[0108] Preferably, the steps of the design method of the buckling-resistance brace structure may further include S400 determining the diameter of the connection portion 3, when the connection load P of the buckling-resistance brace structure is unstable cr,g When the load capacity is greater than twice the design load-bearing capacity of the buckling-restrained brace structure, the lateral stiffness K in the first direction that the buckling-restrained brace needs to provide to the main structure is determined based on the selected parameters of the core unit 1 and the constraint unit 2. e The stiffness of the core unit 1 in the first direction is K1, and the stiffness of the constraint unit 2 in the first direction is K2. By calculating the predetermined stiffness To determine the diameter of the connecting portion 3. Taking the connecting portion 3 as a bolt as an example, the nominal diameter of the bolt can be determined according to the national standard parameters of the bolt.

[0109] Preferably, the steps of the design method of the anti-buckling support structure may also include S500 determining the length of the connecting portion 3, determining the length of the connecting portion 3 according to the diameter of the connecting portion 3, so that the length of the connecting portion 3 is greater than or equal to three times the diameter of the connecting portion 3.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A buckling-resistance support structure for supporting a main structure, characterized in that: The invention comprises a core unit, a constraint unit and a connecting portion, wherein the core unit extends along a first direction, the constraint unit is sleeved on the outside of the core unit, the connecting portion is provided at both ends of the core unit in the first direction, the core unit is connected to the constraint unit via the connecting portion, and the shear stiffness of the connecting portion is equal to a predetermined stiffness, so that when the total deformation of the core unit along the first direction exceeds the expected displacement, the connecting portion can be sheared; The core unit is made of negative Poisson's ratio steel, and the constraint unit is made of ultra-high performance concrete; The cross section of the core unit obtained by cutting it with a plane perpendicular to the first direction is a rectangle, and the width-to-thickness ratio of the rectangle is 5 to 10; The ultimate strength of the core unit is greater than or equal to 800 MPa, and the elongation of the core unit is greater than or equal to 40%; The compressive strength of the constraint unit is greater than or equal to 120 MPa, the tensile strength of the constraint unit is greater than or equal to 10 MPa, and the ultimate tensile strain of the constraint unit is greater than or equal to 2000 με; The constraint unit includes two constraint parts, each of which includes a fitting surface and a groove, wherein the groove is concave from the fitting surface to the interior of the constraint part, and when the two constraint parts are in a state of being engaged with each other along the second direction, the fitting surfaces of the two constraint parts fit together, so that the grooves of the two constraint parts enclose a placement channel that passes through the constraint unit along the first direction, and the core unit passes through the placement channel, and the second direction is the thickness direction of the core unit; The thickness of the two side walls of the groove in the third direction is greater than or equal to 30 mm, and the third direction is perpendicular to the first direction and the second direction respectively; The buckling-resistance support structure further includes a hoop portion, which is arranged on the outside of the two restraint portions when the two restraint portions are in a state of being buckled with each other.

2. The buckling-resistance brace structure according to claim 1, wherein: The number of the connecting parts is n, and the buckling-resistance brace structure needs to provide the main structure with a lateral stiffness in the first direction of K. e , the stiffness of the core unit in the first direction is K1, and the stiffness of the constraint unit in the first direction is K2; Wherein, the predetermined stiffness .

3. The buckling-resistance brace structure according to claim 1, wherein: The constraint unit further includes: an elastic close-fitting layer, wherein when the two restraining parts are in a state of being buckled with each other, the contact surfaces of the two restraining parts are contacted via the elastic close-fitting layer; The spacer layer is arranged between the inner wall of the placement channel and the core unit to reduce the friction between the core unit and the constraint unit.

4. The buckling-resistance brace structure according to claim 3, wherein: The elastic adhesion layer is made of elastic material, and the thickness of the elastic adhesion layer is 2-3 mm; The spacer layer is made of a non-adhesive material and has a thickness of 2 to 3 mm; The volumetric hoop ratio of the hoop portion is greater than or equal to 2%.

5. The buckling-resistance brace structure according to claim 1, wherein: The connecting portion is a stud, which extends along the second direction. Part of the stud is embedded in the constraint unit. The depth of the stud embedded in the constraint unit in the second direction is greater than or equal to three times the nominal diameter of the stud.

6. A method for designing a buckling-resistance brace structure, characterized in that: For designing a buckling-resistance brace according to any one of claims 1 to 5, the method for designing a buckling-resistance brace comprises: Iterative calculation determines the preset value, and according to the shock absorption target of the main structure, the support length L of the anti-buckling brace structure and the initial stiffness K of the anti-buckling brace structure are determined by iterative calculation. e and the design bearing capacity P of the buckling-restrained brace structure y ; Selecting parameters of the core unit and the constraint unit; Evaluate the stability of the buckling-resistance brace structure, calculate the elastic modulus E1 and the bending moment of inertia I1 of the core unit based on the parameters of the core unit, calculate the elastic modulus E2 and the bending moment of inertia I2 of the constraint unit based on the parameters of the constraint unit, determine the calculation length coefficient μ considering the constraint conditions at both ends of the support, and determine the connection load P of the buckling-resistance brace structure that causes support instability. cr,g Is it greater than twice the design bearing capacity of the buckling-restrained brace structure, wherein: .

7. The method for designing a buckling-resistance brace structure according to claim 6, wherein: The design method of the buckling-restrained brace structure further comprises the following steps: If the connection load P of the buckling-restrained brace structure fails cr,g If the load is less than or equal to twice the design bearing capacity of the buckling-restrained brace, the parameters of the core unit and the constraint unit are adjusted, and the step of evaluating the stability of the buckling-restrained brace is repeated until the connection load P of the buckling-restrained brace causes instability. cr,g Greater than twice the design bearing capacity of the buckling-restrained brace structure; When the support of the buckling-restrained brace structure fails, the connection load P cr,g When the load capacity is greater than twice the design load-bearing capacity of the buckling-restrained brace structure, the lateral stiffness K that the buckling-restrained brace needs to provide to the main structure in the first direction is determined based on the selected parameters of the core unit and the constraint unit. e The stiffness of the core unit in the first direction is K1, and the stiffness of the constraint unit in the first direction is K2. By calculating the predetermined stiffness , to determine the diameter of the connecting portion.

8. The method for designing a buckling-resistance brace structure according to claim 7, wherein: The length of the connecting portion is determined according to the diameter of the connecting portion, so that the length of the connecting portion is greater than or equal to three times the diameter of the connecting portion.

9. The method for designing a buckling-resistance brace structure according to claim 6, wherein: The step of selecting parameters of the core unit and the constraint unit includes: Determine the cross-sectional area of ​​the core unit, select the material of the core unit, obtain the stiffness setting value f of the core unit, and calculate the stiffness of the core unit by P y =fA i Calculate the cross-sectional area A of the core unit i ; Determine the width b of the cross section of the core unit i and thickness, according to the cross-sectional area A of the core unit i , and the width b of the cross section of the core unit i The ratio of the core unit to the thickness is between 5 and 10, and the width b of the cross section of the core unit is selected. i and thickness; Determine the width b of the cross section of the constraint unit o ≥b i +60mm; According to the width b of the cross section of the constraint unit o The number n of the connecting portions is determined.

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