Double-yield-point perforation tie type fabricated buckling restrained brace with built-in I-shaped negative poisson ratio peanut hole net inner core

Abstract

The invention provides a double-yield-point perforation tie type fabricated buckling restrained brace with a built-in I-shaped negative Poisson ratio peanut hole net inner core, which comprises an I-shaped steel first-order inner core, a second-order inner core, a third-order inner core, a third-order inner core, a fourth-order inner core and a fourth-order inner core, the linear steel second-order inner core comprises a middle peanut hole net weakening area II; the periphery of the channel steel is restrained and comprises a third middle restraining area; the flat plate periphery constraint comprises a middle constraint area IV; the two groups of channel steel peripheral constraints and the two groups of linear steel second-order inner cores are mounted on two sides of a web plate of the I-shaped steel first-order inner core from outside to inside through high-strength bolt penetrating and tying, and the two groups of flat plate peripheral constraints are mounted on an upper flange and a lower flange of the I-shaped steel first-order inner core through high-strength bolt penetrating and tying; the I-shaped steel first-order inner core can generate longitudinal sliding of a first displacement relative to the straight-line-shaped steel second-order inner core, and the straight-line-shaped steel second-order inner core can generate longitudinal sliding of a second displacement relative to the channel steel peripheral constraint and the flat plate peripheral constraint. Through the first-order and second-order negative Poisson's ratio energy dissipation inner cores, high-ductility fracture-free double-order energy dissipation is achieved, and the mechanical property of the support is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of building structures, in particular to prefabricated assembled steel structures, and specifically to a double-yield point perforated tie-knot assembled buckling restrained brace with a built-in I-shaped negative Poisson's ratio peanut mesh core. Background Art

[0002] Buckling-resistance braces are widely used in seismic structures. Their main feature is that they can maintain good load-bearing capacity and ductility during both tension and compression, thereby improving the seismic performance of the structure. Traditional buckling-resistance braces are usually composed of core yielding elements, constraint elements, and filling materials. External constraint elements prevent the core elements from buckling as a whole due to compression, allowing the brace to effectively dissipate energy under both tension and compression. However, traditional buckling-resistance braces still have certain limitations in certain application scenarios. For example:

[0003] 1. The single-order yield mode may lead to limited energy dissipation efficiency, making it difficult to achieve more stable hysteretic performance.

[0004] 2. Core components are susceptible to fracture: After experiencing multiple strong earthquakes, the core components' limited fatigue resistance makes them susceptible to fatigue fracture under alternating tension and compression loading. This phenomenon is particularly evident under repeated high-intensity earthquakes, where microstructural damage accumulates, ultimately leading to the formation and propagation of cracks. With increasing repeated post-earthquake loading, the core components' resistance gradually declines, resulting in noticeable damage or fracture, which seriously impacts their service life and safety.

[0005] 3. Local buckling leads to performance degradation: Under high axial pressure, the core components are prone to out-of-plane deformation and local buckling. Although the peripheral restraint device provides a limiting effect, it often fails due to uneven restraint or core geometric design defects.

[0006] As building sizes and heights increase, along with increasing seismic fortification requirements, higher demands are placed on the performance of buckling-restrained braces. The design of structural components must not only meet the requirements of efficient energy dissipation and seismic resistance, but also take into account rapid post-earthquake repair and resource reuse.

[0007] Based on the above problems and challenges, it is necessary to optimize the structural structure to effectively solve the problems of easy fracture, buckling instability and complex post-earthquake repair of traditional buckling restrained support core components, and provide an innovative and efficient solution for buildings in high-intensity earthquake areas. Summary of the Invention

[0008] In response to the shortcomings of existing technologies, this invention provides a double-yield-point, perforated, tie-type prefabricated buckling-restrained brace with an I-shaped, negative Poisson's ratio peanut-shaped mesh core. This design aims to address the problems of buckling-restrained braces, such as insufficient ductility, fragility, and limited energy dissipation, under high-intensity earthquakes. Through innovative geometric design and material optimization, this brace significantly enhances its energy dissipation capacity, deformation performance, and structural stability.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] The present invention first provides a double-yield point perforated tie-knot assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh inner core, comprising:

[0011] The first-order core of the I-beam includes a central peanut hole network weakening area formed within a predetermined length range in the middle of the steel and an end connection area at both ends;

[0012] The second-order core of the I-shaped steel section includes a second weakened area of ​​a peanut hole network formed within a predetermined length range in the middle of the steel section, and second end connection areas at both ends;

[0013] The peripheral constraint of the channel steel includes a middle constraint zone 3 formed by a predetermined length range in the middle of the channel steel, and end connection zones 3 at both ends;

[0014] The peripheral constraint of the plate includes a middle constraint area 4 formed within a predetermined length range in the middle of the plate, and end connection areas 4 at both ends;

[0015] The two groups of channel steel peripheral constraints and the two groups of I-shaped steel second-order cores are installed on both sides of the web of the I-shaped steel first-order core from the outside to the inside through high-strength bolts through holes and tensioning. The two groups of flat plate peripheral constraints are installed on the upper and lower flanges of the I-shaped steel first-order core through high-strength bolts through holes and tensioning. The I-shaped steel first-order core can produce a first displacement longitudinal sliding relative to the I-shaped steel second-order core, and the I-shaped steel second-order core can produce a second displacement longitudinal sliding relative to the channel steel peripheral constraints and the flat plate peripheral constraints, and the second displacement is greater than the first displacement.

[0016] In one embodiment, the peanut hole network weakening area in the middle of the first-order core of the I-beam is formed by opening peanut holes in the web and upper and lower flanges of the I-beam to form a negative Poisson's ratio effect; the peanut holes are arranged in a horizontal and vertical array in the peanut hole network weakening area.

[0017] The second weakened area of ​​the middle peanut hole network of the second-order core of the I-shaped steel is provided with peanut holes to form a negative Poisson's ratio effect; the peanut holes are arranged in a horizontally and vertically alternating array in the second weakened area of ​​the middle peanut hole network.

[0018] In one embodiment, the web and the upper and lower flanges of the end connection area 1 are provided with a circular hole 1;

[0019] The second end connection area is provided with a second oblong hole, and the second oblong hole corresponds to the first circular hole;

[0020] The web and upper and lower flanges of the end connection area 3 are provided with oblong holes 3, the oblong holes 3 of the web correspond to the oblong holes 2 and the circular holes 1 of the web of the end connection area 1, and the oblong holes 3 of the upper and lower flanges correspond to the circular holes 1 of the upper and lower flanges of the end connection area 1;

[0021] The end connection area 4 is provided with an oblong hole 4, which corresponds to the oblong hole 1 on the upper and lower flanges of the end connection area 1 and the oblong hole 3 on the upper and lower flanges of the end connection area 3, and the oblong hole 4 is of the same length as the oblong hole 3 and is longer than the oblong hole 2;

[0022] The connection is fixed by passing through the oblong hole three of the web plate of the end connection area three, the oblong hole two, and the circular hole one of the web plate of the end connection area one through the end high-strength bolt group one; the connection is fixed by passing through the oblong hole four, the circular hole one of the upper and lower flanges of the end connection area one, and the oblong hole three of the upper and lower flanges of the end connection area three through the end high-strength bolt group two.

[0023] In one embodiment, a circular hole three is opened in the web of the third middle constraint zone of the peripheral constraint of the channel steel, and is connected and fixed by a group of middle tie bolts passing through the circular hole three, the peanut holes of the second middle peanut hole mesh weakening zone, and the peanut holes of the web of the first middle peanut hole mesh weakening zone.

[0024] In one embodiment, circular hole three is provided in the upper and lower flanges of the middle constraint zone three of the peripheral constraint of the channel steel, and circular hole four is provided in the middle constraint zone four of the peripheral constraint of the flat plate. The middle tie bolt group two passes through the circular hole four, the peanut holes on the upper and lower flanges of the middle peanut hole mesh weakening zone one, and the circular hole three for connection and fixation.

[0025] In one embodiment, the length L1 of the first-order core of the I-beam, the length L2 of the second-order core of the I-beam, the length L3 of the peripheral constraint of the channel steel, and the length L4 of the peripheral constraint of the flat plate satisfy L1>L2=L3=L4, and the excess parts at both ends of the first-order core of the I-beam are used to connect to the main structure of the building.

[0026] In one embodiment, a gap of at least 1 mm is reserved between the first-order core of the I-beam and the second-order core of the I-beam, between the second-order core of the I-beam and the peripheral constraint of the channel steel, and between the peripheral constraint of the flat plate and the first-order core of the I-beam.

[0027] In one embodiment, the gap is filled with polytetrafluoroethylene.

[0028] In one embodiment, the first-order core of the I-beam and the second-order core of the I-beam are made of high-ductility materials, including Q235 steel, aluminum alloy, and shape memory alloy.

[0029] The present invention also provides an application of the buckling restrained brace in multi-story and high-rise prefabricated buildings.

[0030] The beneficial effects of the present invention compared to the prior art are: the double-yield point perforated tie-knot type assembled buckling restrained support with a built-in I-shaped negative Poisson's ratio peanut hole mesh core provided by the present invention effectively improves the mechanical properties of the support through the first-order and second-order negative Poisson's ratio energy-absorbing core.

[0031] Specifically, it can at least bring the following beneficial effects:

[0032] 1. The present invention is designed based on the concept of centralized control of plastic damage and replaceable energy-absorbing components. All plastic damage can be centralized and controlled on the energy-absorbing components, that is, all plastic damage is controlled on the weakened sections of the first-order and second-order negative Poisson's ratio energy-absorbing inner core and outer core. After an earthquake, only the energy-absorbing inner core needs to be replaced to quickly restore the original bearing capacity of the entire structure, significantly improving the sustainable maintenance performance of the building structure.

[0033] 2. The present invention effectively improves the ductility of the energy-absorbing inner core and outer core by providing holes with negative Poisson's ratio characteristics on the energy-absorbing inner core and outer core. Based on the tensile expansion effect of the negative Poisson's ratio material, the ultimate deformation capacity of the energy-absorbing component is significantly improved, so that the support system forms a stable energy-absorbing mechanism under cyclic loads. Based on finite element analysis, the negative Poisson's ratio inner core has a smaller thickness requirement for the peripheral components than the dog-bone weakening form. In the present invention, the thickness of the constrained channel steel can be effectively controlled, which can save steel to a certain extent and reduce costs.

[0034] 3. The first-order negative Poisson's ratio energy dissipation core of this invention utilizes an I-shaped cross-section. This I-shaped cross-section has a large moment of inertia and greater bending stiffness, effectively resisting lateral deformation under axial pressure and reducing the risk of overall buckling. The synergistic effect of the flange and web disperses stress concentration, avoiding premature failure due to local buckling, as is the case with flat plate cross-sections.

[0035] 4. The present invention connects the peripheral restraint components on both sides by peripheral connecting bolts through the negative Poisson's ratio energy dissipation inner core and the outer core. The bolt penetration and connection design can realize the miniaturization and lightweight of the peripheral restraint components, and effectively solve the problems of large cross-section and heavy components of traditional integral restraint type and fully assembled binding restraint type buckling restraint support peripheral components.

[0036] 5. The present invention, through the bolt hole opening structure described above, gives the support system a multi-stage energy dissipation timing control characteristic, and its static hysteresis curve shows a significant double yield platform feature, forming a gradient yield mechanism that matches the multi-level earthquake motion. When the structure encounters a small earthquake, the first-order and second-order negative Poisson's ratio energy dissipation cores maintain the overall stiffness of the structure through cooperative deformation; under the excitation of a moderate earthquake, the first-order negative Poisson's ratio core first enters the plastic energy dissipation stage to achieve energy dissipation; when a large earthquake occurs, the outer constraint channel steel and the second-order negative Poisson's ratio core are pressed tightly, triggering the plastic deformation of the second-order core, and the first and second-order negative Poisson's ratio cores jointly dissipate the seismic energy. It should be noted that the time the second-order negative Poisson's ratio energy dissipation core is subjected to force is determined by the length of the oblong hole, which can be flexibly adjusted according to actual needs.

[0037] 6. Anti-fracture mechanism. Because the first-order negative Poisson's ratio energy dissipation core is always under stress during support deformation, there is a potential risk of fracture under large earthquakes and large deformations. Even if the first-order negative Poisson's ratio energy dissipation core breaks, the bolts slide and tighten against the oblong holes in the constraining channel and the constraining plate, allowing the constraining channel and the constraining plate to share the load, providing a last line of defense.

[0038] 7. Coordinated deformation capability. The present invention effectively coordinates inter-story deformation through rational design. Specifically, buildings equipped with traditional buckling-restrained braces have distinct weak layers, which carry a higher risk of failure under major earthquakes. However, buildings equipped with the present invention effectively avoid this weak layer effect through rational design of the supports on each floor.

[0039] 8. All welding processes in this invention can be completed in a prefabrication plant, which produces standard "modules." Construction sites only need to locate the modules according to the reserved bolt holes and assemble them using high-strength bolts to complete the structural installation. This highly modular construction concept reduces labor and eases construction difficulty, effectively shortening the construction period.

[0040] 9. The present invention can be applied to a single-story building, and can also be combined with detachable and replaceable shear walls, energy-absorbing supports, etc. to form a frame-shear wall system or a frame-support system, and can be flexibly applied to multi-story and high-rise building systems.

[0041] It should be understood that the implementation of any embodiment of the present invention does not mean that multiple or all of the above-mentioned beneficial effects must be possessed or achieved at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can, without inventive effort, derive other implementation drawings based on the provided drawings.

[0043] The structures, proportions, sizes, etc. illustrated in this specification are intended solely to complement the contents disclosed herein and to facilitate understanding and reading by persons skilled in the art. They are not intended to limit the conditions under which the present invention may be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes, provided they do not affect the efficacy and objectives of the present invention, shall remain within the scope of the technical contents disclosed herein.

[0044] Figure 1 An isometric diagram of a double-yield point perforated tie-type assembled buckling-restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0045] Figure 2 An exploded view of a double-yield point perforated tie-type assembled buckling-restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0046] Figure 3 An exploded view of a double-yield point perforated tie-knot type buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0047] Figure 4 A schematic diagram of the first-order core structure of an I-shaped steel structure with a double-yield point perforated tie-tie assembled buckling-restrained brace having an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0048] Figure 5 A schematic diagram of a structure of two I-shaped steel second-order cores of a double-yield point perforated tie-type assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0049] Figure 6 A schematic diagram of the two channel steel peripheral restraint structures of a double-yield point perforated tie-type assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0050] Figure 7 A schematic diagram of two flat plate peripheral restraint structures of a double-yield point perforated tie-type assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0051] Figure 8A front view of a double-yield point perforated tie-knot assembled buckling-restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0052] Figure 9 A top view of a double-yield point perforated tie-type assembled buckling-restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example;

[0053] Figure 10 A cross-sectional view of a double-yield point perforated tie-knot assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core is shown as an example.

[0054] Markings in the figure:

[0055] The first-order core of the I-beam is 1, the middle peanut hole network weakening area is 11, the end connection area is 12, and the circular hole is 121;

[0056] I-shaped steel second-order core 2, middle peanut hole mesh weakening area 21, end connection area 22, oblong hole 221;

[0057] Channel steel outer constraint 3, middle constraint area 31, round hole 311, end connection area 32, oblong hole 321;

[0058] Flat plate peripheral constraint 4, middle constraint area 41, circular hole 411, end connection area 42, oblong hole 421;

[0059] End high-strength bolt group 1-5;

[0060] End high-strength bolt group 26;

[0061] Middle tie bolt group 17;

[0062] Middle tie bolt group 28.

[0063] In the various drawings, the same or corresponding reference numerals denote the same or corresponding parts. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in conjunction with the embodiments and drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0065] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0066] It should be understood that the terms "comprises / comprising," "consisting of," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product, apparatus, process, or method that includes a list of elements includes not only those elements but also, if necessary, other elements not explicitly listed, or elements inherent to such product, apparatus, process, or method. In the absence of further limitations, elements defined by the phrases "comprises / comprising," "consisting of," do not preclude the presence of additional identical elements in the product, apparatus, process, or method that includes the elements.

[0067] It should also be understood that terms such as "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device, component or structure referred to must have a specific direction, be constructed or operate in a specific direction, and should not be understood as limiting the present invention.

[0068] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0069] The specific implementation and preferred scheme of the double-yield point perforated tie-knot assembled buckling restrained support with a built-in I-shaped negative Poisson's ratio peanut mesh core proposed by the present invention are described in detail below.

[0070] Research on negative Poisson's ratio materials originated in the 1980s. Scientists discovered that certain unique microstructures or material geometries can lead to the negative Poisson's ratio effect. From a microscopic perspective, the structural units of these materials undergo a unique rotation or twisting when deformed by stress, resulting in lateral deformation opposite to that of traditional materials. When a negative Poisson's ratio component is subjected to external tensile or compressive forces, the periodic negative Poisson's ratio cells within it utilize their inherent in-plane rotation mechanism to promote good deformation performance, thereby dissipating more external energy. Due to their excellent energy absorption capabilities, negative Poisson's ratio structures are widely used in many fields, including protection, shock absorption, and energy absorption.

[0071] Double-yield-point supports have two yield stages, gradually yielding and dissipating energy under varying stress levels. During minor and moderate earthquakes, double-yield-point supports begin dissipating energy at the lower yield point and, during major earthquakes, continue dissipating energy at the higher yield point, resulting in a smoother and more continuous energy dissipation process. Compared to single-yield-point supports, double-yield-point supports are more efficient in dissipating energy and enable better staged control of structural energy dissipation, further limiting inter-story drift.

[0072] Based on the above understanding, the present invention proposes a double-yield point perforated tie-type assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core, such as Figure 1-3 As shown, it mainly includes: an I-beam first-order core 1, an I-beam second-order core 2, a channel steel peripheral restraint 3, a flat plate peripheral restraint 4, and multiple groups of high-strength bolts. The above specimens are all processed in the prefabrication factory and only need to be connected on site with high-strength bolts. The I-beam second-order core 2 and the channel steel peripheral restraint 3 are arranged in sequence from the inside to the outside on the web of the I-beam first-order core 1. The flat plate peripheral restraint 4 covers the upper and lower flanges of the I-beam first-order core 1. Two groups of I-beam second-order cores 2 are installed on both sides of the web of the I-beam first-order core 1 and can generate longitudinal sliding of a first displacement. Two groups of channel steel peripheral restraints 3 are installed on both sides of the two groups of I-beam second-order cores 2. Two groups of flat plate peripheral restraints 4 are installed on the upper and lower flanges of the I-beam first-order core 1 and can generate longitudinal sliding of a second displacement. The second displacement is greater than the first displacement, for example, the first displacement is 5-10 times the yield displacement, and the second displacement is 25-30 times the yield displacement. In this way, the obtained structure has a double yield point, which can make the support have two yield stages when the structure undergoes large deformation, thereby improving the overall ductility of the structure and preventing the component from breaking with the help of the external constraint effect.

[0073] For details, see Figure 4 , exemplarily showing an I-steel first-stage core structure, the I-steel first-stage core 1 is made of I-steel and serves as the internal core of the entire component. The so-called I-steel is an I-shaped cross-section, of course, H-steel can also be used.

[0074] The first-order core 1 of the I-beam first features a central peanut-hole mesh weakening zone 11. This zone is located within a predetermined length range in the middle of the steel section, with the specific weakening length and degree determined by design requirements. As the core component of the core, the central weakening zone is specifically designed as a weakening area to control the plastic deformation range of the component. By weakening this central region, its bearing capacity is lower than that of other external areas. The design of this area effectively guides plastic deformation to the middle of the member, preventing excessive plastic deformation or damage in other areas, thereby improving the system's energy dissipation capacity.

[0075] In this embodiment, the central peanut hole network weakening zone 11 is weakened by providing peanut holes. The so-called peanut holes are peanut-shaped through-holes, which are easy to understand. The peanut holes are arranged in a horizontal and vertical pattern within the central peanut hole network weakening zone 11, alternating horizontally and vertically. The array is arranged in multiple rows and columns, with one horizontal peanut hole alternating with a vertical peanut hole in the same row, and one vertical peanut hole alternating with a horizontal peanut hole in the same column. By designing a peanut hole weakening pattern within the central weakening zone and setting a reasonable aperture ratio, a negative Poisson's ratio effect is achieved in the component, causing the core component to exhibit lateral contraction when subjected to stress. This avoids the buckling instability caused by lateral expansion in traditional structures and achieves a buckling-free effect. Furthermore, this negative Poisson's ratio property gives the core component greater ductility, improving its ductility and durability, enabling it to maintain stable performance under multiple earthquake loads. Furthermore, this property optimizes the energy dissipation mechanism, enhancing the structure's energy absorption and seismic resistance under extreme loads. At the same time, by changing the cross-sectional shape of this area so that its bearing capacity is lower than that of the end reinforced connection area and the external connection area, the plastic deformation is effectively guided to occur in the middle of the component, preventing excessive plastic deformation or damage in other areas, thereby improving the energy dissipation capacity of the system.

[0076] The porosity of the peanut hole is determined according to the design requirements. If the porosity is too small, the negative Poisson's ratio effect is difficult to reflect. If the porosity is too large, the structural strength is difficult to ensure. Studies have shown that an opening rate of 40-50% is appropriate, that is, a solid rate of 50-60% is a reasonable range.

[0077] Of course, in addition to peanut holes, elliptical holes, star-shaped holes, etc. can also be used to make the inner core have negative Poisson's ratio characteristics.

[0078] The first-stage core 1 of the I-shaped steel further comprises an end connection area 12, which is located at both ends of the middle peanut hole network weakened area 11, and a circular hole 121 is provided in the end connection area 12; Figure 4As shown, the web of the end connection region 12 of the first-order core 1 of the I-beam is symmetrically provided with six circular holes 121 in two rows, one above the other. Furthermore, the upper and lower flanges on each side of the end connection region 12 also symmetrically provide six circular holes 121 in two rows, one above the other. The end connection region 12 is used to connect to the second-order core and the peripheral constraints.

[0079] Continue to see Figure 5 , an example of a one-line steel second-order core structure is shown, and the one-line steel second-order core 2 adopts a one-line steel plate, that is, a strip steel plate. It first has a middle peanut hole mesh weakening area 21, and the middle peanut hole mesh weakening area 21 is located within a predetermined length range in the middle of the one-line steel second-order core 2. The specific weakening length and weakening degree are determined according to design requirements. As the core part of the second-order core component, the middle weakening area is specially designed as a weakening area to control the plastic deformation area of ​​the component. By weakening the central area, its bearing capacity is lower than other external areas. The design of this area effectively guides the plastic deformation to occur in the middle of the rod, prevents excessive plastic deformation or damage in other areas, and thus improves the energy dissipation capacity of the system.

[0080] Similarly, peanut holes are provided in the second weakened area 21 of the middle peanut hole network. The design of the peanut holes can be the same as that of the peanut holes on the first weakened area 11 of the middle peanut hole network, or can be determined according to design requirements.

[0081] It should be noted that the opening form must first make the first-order core and the second-order core show a negative Poisson's ratio effect. Since the opening form of the second-order core 2 of the I-beam and the first-order core 1 of the I-beam can be the same or different, the negative Poisson's ratio effect can be achieved as long as it is controlled within a reasonable opening range.

[0082] The second-stage inner core 2 of the I-shaped steel also has an end connection area 22, which is located at the two ends outside the middle peanut hole mesh weakened area 21, and the end connection area 22 is provided with an oblong hole 221; as shown in the figure, corresponding to the end connection area 12, the end connection area 22 of the second-stage inner core 2 of the I-shaped steel is symmetrically provided with six oblong holes 221 in two rows, close to the upper and lower edges.

[0083] By setting the end connection area 22 at both ends of the middle peanut hole mesh weakened area 21, the area is designed with a hole of a specific shape, and the semicircular size of the oblong hole 221 is consistent with the size of the circular hole 121, that is, the oblong hole 221 of the end connection area 22 is matched with the circular hole 121 of the end connection area 12, so that the I-shaped steel first-order core 1 and the I-shaped steel second-order core 2 are connected and fixed in this area by the end high-strength bolt group 5, as shown in FIG. Figure 8When the component is subjected to stress, such as when the earthquake intensity is low, the first-order core 1 of the I-beam deforms first, which is the first-order energy dissipation. When the earthquake intensity is high, as the deformation gradually intensifies, the end high-strength bolt group 1 in the second oblong hole 221 gradually contacts and becomes stuck with the wall of the first circular hole 121. At this time, the second-order core 2 of the I-beam begins to bear part of the load, providing additional support force. This is the second-order energy dissipation, thus achieving the effect of a double yield point.

[0084] See also Figure 6 , an example of a channel steel peripheral constraint structure is shown. The channel steel peripheral constraint 3 first forms a middle constraint area three 31 within a predetermined length range in the middle of the channel steel. The middle constraint area three is used to constrain the internal I-beam first-order core 1 and the I-beam second-order core 2, providing the last line of defense to prevent the I-beam first-order core 1 (web and upper and lower flanges) and the I-beam second-order core 2 from buckling instability.

[0085] In addition, the channel steel peripheral constraint 3 also has end connection areas 32 at both ends of the middle constraint area 31. The end connection area 32 is provided with oblong holes 321 corresponding to the oblong holes 221. The figure shows that six oblong holes 321 are symmetrically provided in two rows, upper and lower, on the web of the end connection area 32 of the channel steel peripheral constraint 3. At the same time, six oblong holes 321 are symmetrically provided in two rows, upper and lower, on the upper and lower flanges of the end connection area 32.

[0086] The semicircular dimensions of oblong hole three 321 and oblong hole two 221 match those of circular hole one 121. They are connected by a group of high-strength bolts, allowing the high-strength bolts to slide from one end of the oblong hole to the other, thereby transmitting force through the high-strength bolts. Furthermore, oblong hole three 321 is longer than circular hole two 221. For example, oblong hole three 321 is an oblong hole with a longer straight section, while oblong hole two 221 is an oblong hole with a shorter straight section. When the component is subjected to force, the first-stage core 1 of the I-beam deforms first. As the deformation gradually intensifies, the high-strength bolt group one 5 at the end is allowed to move within the oblong hole until the high-strength bolts gradually contact the wall of oblong hole two 221 and become stuck. At this point, the second-stage component begins to bear part of the load, providing additional support, thus achieving a double yield point effect and enhancing the load-bearing capacity of the entire component. As the deformation continues to intensify, the high-strength bolt gradually contacts the wall of the oblong hole 321 and is stuck. At this time, the outer constraint 3 of the channel steel provides a restraint effect to prevent the component from breaking and buckling instability.

[0087] Continue to see Figure 7 , an example of a flat plate peripheral constraint structure is shown. The flat plate peripheral constraint 4 first includes a middle constraint area 41 formed within a predetermined length range in the middle of the flat plate. The middle constraint area 41 is used to constrain the internal I-beam first-order core 1, providing the last line of defense to prevent the I-beam first-order core 1 (flange) from buckling and instability.

[0088] Similarly, both ends of the flat plate peripheral constraint 4 have end connection areas 42, and the end connection areas 42 are provided with oblong holes 421. The oblong holes 421 correspond to the circular holes 121 on the upper and lower flanges of the first-stage core 1 of the I-beam and the oblong holes 321 on the upper and lower flanges of the end connection areas 32 of the channel steel peripheral constraint 3. The figure shows that two rows of six oblong holes 421 are symmetrically provided on the edge of the plate body of the end connection areas 42 of the flat plate peripheral constraint 4.

[0089] See Figure 1 、 Figure 8 、 Figure 10 During assembly, two groups of I-shaped steel second-order cores 2 are symmetrically attached to both sides of the web of the I-shaped steel first-order core 1, two groups of channel steel peripheral constraints 3 are symmetrically attached to both sides of the two groups of I-shaped steel second-order cores 2, and two groups of flat plate peripheral constraints 4 are symmetrically attached to the upper and lower flanges of the I-shaped steel first-order core 1. Then, at both ends, the end high-strength bolt group 1 is connected and fixed through the oblong hole 321 of the web, the oblong hole 221 and the circular hole 121 of the web, and the end high-strength bolt group 2 is connected and fixed through the oblong hole 421, the circular hole 121 of the upper and lower flanges and the oblong hole 321 of the upper and lower flanges.

[0090] See also Figure 6 、 Figure 8 A circular hole three 311 is provided in the web of the middle constraint area three 31 of the outer constraint 3 of the channel steel, and is connected and fixed by a middle tie bolt group one 7 passing through the circular hole three 311, the peanut hole of the middle peanut hole mesh weakened area two 21 and the peanut hole of the web of the middle peanut hole mesh weakened area one 11.

[0091] In this embodiment, the purpose of the middle tie bolt group 7 is that, since the web of the I-beam first-order core 1 and the L-beam second-order core 2 are both weakened by holes in the middle, the two groups of channel steel peripheral constraints 3 are fixed to the periphery of the first-order core and the second-order core through the middle tie bolt group 7, so as to provide effective peripheral constraint protection for the first-order core and the second-order core energy-absorbing components, ensure that the first-order core and the second-order core components show the characteristics of lateral contraction when subjected to force, and avoid the problem of buckling instability caused by lateral expansion. At the same time, when experiencing extreme earthquake action, the I-beam first-order core components and the L-beam second-order core components may be fractured due to large deformation. At this time, the channel steel peripheral constraint device continues to bear the load as the last line of defense, thereby achieving the fracture-free characteristic.

[0092] See also Figure 7 、 Figure 8The upper and lower flanges of the middle constraint area 31 of the channel steel peripheral constraint are also provided with round holes 311, and the middle constraint area 41 of the flat plate peripheral constraint 4 is provided with round holes 411, which are connected and fixed by the middle tie bolt group 2 8 passing through the round holes 411, the peanut holes on the upper and lower flanges of the middle peanut hole mesh weakening area 11, and the round holes 311.

[0093] It is also easy to understand that the purpose of the middle tie bolt group 2 8 is to fix the two sets of flat plate peripheral constraints 4 to the upper and lower flanges of the first-order core 1 of the I-beam through the middle tie bolt group 2 8, since the upper and lower flanges of the first-order core 1 of the I-beam are also weakened by the holes opened in the middle. In this way, effective peripheral constraint guarantees are provided for the upper and lower flanges of the first-order core 1 of the I-beam, ensuring that the core component exhibits the characteristics of lateral contraction when subjected to force, avoiding the problem of buckling instability caused by lateral expansion. When experiencing extreme earthquake action, the first-order core component of the I-beam and the second-order core component of the I-beam may be fractured due to large deformation. At this time, the channel steel peripheral constraint device continues to bear the load as the last line of defense, thereby achieving the fracture-free characteristic.

[0094] It should be noted that the two sets of I-beam second-stage cores 2 are symmetrically attached to the two sides of the I-beam first-stage core 1. A certain gap should be maintained between the plate surfaces, for example, at least 1 mm. Alternatively, PTFE filling or PTFE tape can be applied to reduce the effects of friction. Similarly, the two sets of channel steel peripheral restraints 3 are symmetrically arranged on both sides of the two sets of I-beam second-stage cores 2, maintaining a certain gap between the plate surfaces. They are not tightly fitted. The two sets of flat plate peripheral restraints 4 also maintain a certain gap between the plate surfaces and the upper and lower flanges of the I-beam first-stage core 1 to allow for easy relative movement when subjected to force.

[0095] In the embodiment of the present invention, Figure 1 、 Figure 8 As shown, the length L1 of the I-beam's primary core 1, the length L2 of the I-beam's secondary core 2, the length L3 of the channel steel's peripheral restraint 3, and the length L4 of the plate's peripheral restraint 4 satisfy L1>L2=L3=L4. This means the I-beam's secondary core 2, the channel steel's peripheral restraint 3, and the plate's peripheral restraint 4 are of equal length. After assembly, the I-beam's primary core 1 extends at both ends, with the excess portion used for connection to the building's main structure. Furthermore, the I-beam's primary core 1 is inherently I-shaped, so compared to an I-shaped core, no reinforcement is required at either end.

[0096] In the embodiment of the present invention, Figure 10 As shown, the web of the first-order core 1 of the I-beam, the second-order core 2 of the I-beam and the peripheral constraint 3 of the channel steel are of equal width, and the upper and lower flanges of the first-order core 1 of the I-beam and the peripheral constraint 4 of the flat plate are of equal width. The buckling restraint support formed after assembly is relatively regular, or the width of the second-order core 2 of the I-beam is slightly smaller to avoid friction.

[0097] In the embodiment of the present invention, the I-beam primary core 1 and the I-beam secondary core 2 are made of high-ductility materials, such as low-yield point steel (Q235 steel), aluminum alloy, or iron-based shape memory alloy.

[0098] From the above description, it can be known that the double-yield point perforated tie-type assembled buckling restraint support with built-in I-shaped negative Poisson's ratio peanut hole mesh core provided by the present invention is mainly composed of an I-shaped steel first-order core, two I-shaped steel second-order cores, two channel steel peripheral constraints, two flat plate peripheral constraints 4 and a high-strength bolt group; the buckling restraint support can improve the overall ductility of the component and prevent the component from breaking. When the core has a large deformation, the axial force can be transmitted through the I-shaped steel second-order core and the high-strength bolt group outside the core. By opening the I-shaped steel first-order core and the I-shaped steel second-order core, the axial force can be transmitted through the I-shaped steel second-order core and the high-strength bolt group outside the core. The peanut holes give the structure a negative Poisson's ratio, and the peripheral restraint device prevents buckling instability and fracture in the first-order core of the I-beam and the second-order core of the I-beam. When the first-order core of the I-beam is subjected to axial force, the negative Poisson's ratio allows the structure to absorb external force energy through special deformation behavior (bending, torsion, or other nonlinear deformations), converting the externally absorbed mechanical energy into elastic or plastic energy. Furthermore, negative Poisson's ratio structures have high toughness and plasticity, which means that under the action of external forces, they can undergo large deformations without easily suffering brittle fracture. This plastic deformation absorbs a large amount of energy, effectively protecting the structure from severe impact or overload.

[0099] When the deformation of the first-order core of the I-beam enters the plastic stage, the first stage of yielding of the structure begins. As the axial force increases, the second-order core of the I-beam begins to share the axial force exerted on the first-order core of the I-beam with the help of the movement of the high-strength bolt group in the oblong hole, and gradually enters the plastic state, so that the support has two yield stages and achieves higher energy consumption efficiency.

[0100] When both the first-order core of the I-beam and the second-order core of the I-beam undergo significant deformation, the peripheral restraint device acts as a buckling restraint from the outside, thereby preventing the support from breaking, and can effectively achieve the buckling restraint of the first-order core of the I-beam and the second-order core of the I-beam; and when the first-order core and the second-order core fail, the axial force will be transmitted to the peripheral restraint of the channel steel and the peripheral restraint of the flat plate through the high-strength bolt group, and the peripheral restraint of the channel steel and the peripheral restraint of the flat plate will continue to bear greater internal forces.

[0101] Although several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the present invention. Certain features described in the context of separate embodiments may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented in multiple implementations individually or in any suitable sub-combination.

Claims

1. A double-yield point perforated tie-type assembled buckling restrained brace with an I-shaped negative Poisson's ratio peanut mesh core, characterized in that: include: The first-order core of the I-beam includes a central peanut hole network weakening area formed within a predetermined length range in the middle of the steel and an end connection area at both ends; The second-order core of the I-shaped steel section includes a second weakened area of ​​a peanut hole network formed within a predetermined length range in the middle of the steel section, and second end connection areas at both ends; The peripheral constraint of the channel steel includes a middle constraint zone 3 formed by a predetermined length range in the middle of the channel steel, and end connection zones 3 at both ends; The peripheral constraint of the plate includes a middle constraint area 4 formed within a predetermined length range in the middle of the plate, and end connection areas 4 at both ends; The two groups of channel steel peripheral constraints and the two groups of I-shaped steel second-order cores are installed on both sides of the web of the I-shaped steel first-order core from the outside to the inside through high-strength bolts through holes and tensioning. The two groups of flat plate peripheral constraints are installed on the upper and lower flanges of the I-shaped steel first-order core through high-strength bolts through holes and tensioning. The I-shaped steel first-order core can produce a first displacement longitudinal sliding relative to the I-shaped steel second-order core, and the I-shaped steel second-order core can produce a second displacement longitudinal sliding relative to the channel steel peripheral constraints and the flat plate peripheral constraints, and the second displacement is greater than the first displacement.

2. The buckling-restrained brace according to claim 1, wherein: The peanut hole network weakened area in the middle of the first-order core of the I-shaped steel is provided with peanut holes on the web and upper and lower flanges of the I-shaped steel to form a negative Poisson's ratio effect; the peanut holes are arranged in a horizontal and vertical alternating array in the peanut hole network weakened area in the middle; The second weakened area of ​​the middle peanut hole network of the second-order core of the I-shaped steel is provided with peanut holes to form a negative Poisson's ratio effect; the peanut holes are arranged in a horizontally and vertically alternating array in the second weakened area of ​​the middle peanut hole network.

3. The buckling-restrained brace according to claim 1, wherein: The web and the upper and lower flanges of the end connection area 1 are provided with a circular hole 1; The second end connection area is provided with a second oblong hole, and the second oblong hole corresponds to the first circular hole; The web and upper and lower flanges of the end connection area 3 are provided with oblong holes 3, the oblong holes 3 of the web correspond to the oblong holes 2 and the circular holes 1 of the web of the end connection area 1, and the oblong holes 3 of the upper and lower flanges correspond to the circular holes 1 of the upper and lower flanges of the end connection area 1; The end connection area 4 is provided with an oblong hole 4, which corresponds to the oblong hole 1 on the upper and lower flanges of the end connection area 1 and the oblong hole 3 on the upper and lower flanges of the end connection area 3, and the oblong hole 4 is of the same length as the oblong hole 3 and is longer than the oblong hole 2; The connection is fixed by passing through the oblong hole three of the web plate of the end connection area three, the oblong hole two, and the circular hole one of the web plate of the end connection area one through the end high-strength bolt group one; the connection is fixed by passing through the oblong hole four, the circular hole one of the upper and lower flanges of the end connection area one, and the oblong hole three of the upper and lower flanges of the end connection area three through the end high-strength bolt group two.

4. The buckling-restrained brace according to claim 2, wherein: A circular hole three is opened in the web of the third middle constraint zone of the peripheral constraint of the channel steel, and is fixed by a central tie bolt group one passing through the circular hole three, the peanut holes of the second middle peanut hole mesh weakening zone, and the peanut holes of the web of the first middle peanut hole mesh weakening zone.

5. The buckling-restrained brace according to claim 2, wherein: A circular hole three is provided on the upper and lower flanges of the middle constraint zone three of the peripheral constraint of the channel steel, and a circular hole four is provided on the middle constraint zone four of the peripheral constraint of the flat plate. The middle tie bolt group two passes through the circular hole four, the peanut holes on the upper and lower flanges of the middle peanut hole mesh weakening zone one, and the circular hole three for tie and fixation.

6. The buckling-restrained brace according to claim 1, wherein: The length L1 of the first-order core of the I-beam, the length L2 of the second-order core of the I-beam, the length L3 of the peripheral constraint of the channel steel, and the length L4 of the peripheral constraint of the flat plate satisfy L1>L2=L3=L4, and the excess parts at both ends of the first-order core of the I-beam are used to connect the main structure of the building.

7. The buckling-restrained brace according to claim 1, wherein: A gap of at least 1 mm is reserved between the first-order core of the I-beam and the second-order core of the I-beam, between the second-order core of the I-beam and the peripheral constraint of the channel steel, and between the peripheral constraint of the flat plate and the first-order core of the I-beam.

8. The buckling-restrained brace according to claim 7, wherein: The gap is filled with polytetrafluoroethylene.

9. The buckling-restrained brace according to claim 1, wherein: The first-order core of the I-shaped steel and the second-order core of the I-shaped steel are made of high-ductility materials, including Q235 steel, aluminum alloy, and shape memory alloy.

10. Use of the buckling restrained brace according to any one of claims 1 to 9 in multi-story or high-rise prefabricated buildings.

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