Method for preparing a small-scale model of a buckling control support device with a rotationally symmetric cross section

Abstract

The invention discloses a method for preparing a small-scale model of a buckling control support device with a rotationally symmetrical cross-section, belonging to the technical field of energy-consuming support for building structures, and the preparation method comprises the following steps: S100, a numerically controlled machine tool cuts a flat steel plate into a surface group 1 and a surface group 2 formed by splitting a sub-energy-consuming segment along the fifteenth side and the sixteenth side, wherein the surface group 1 includes the ninth side, the fifteenth side, the sixteenth side, the thirteenth side, the eighth side, the eleventh side, and the fourth side, and the surface group 2 includes the tenth side, the second side, the sixth side, the fourteenth side, the sixteenth side, the twelfth side, and the fifteenth side; S200, the surface group 1 and the surface group 2 in step S100 are connected through a peak line oblique fold to form a sub-energy-consuming segment; S300, the four groups of sub-energy-consuming segments in step S200 are connected along the direction of the eleventh side to form an energy-consuming segment of a tubular rotationally symmetrical structure. The invention reasonably splits and assembles a complex structure, avoids unnecessary force, and is also conducive to mass production.

Description

Technical Field

[0001] The invention belongs to the technical field of energy-absorbing supports for building structures, and in particular relates to a method for preparing a small-scale model of a buckling-controlled support device with a rotationally symmetric cross-section. Background Art

[0002] In the steel frame-center support structure system, the axially stressed steel center support provides the initial stiffness for the structure, but it is prone to overall bending and buckling and instability under the action of axial pressure. In order to solve the problem of instability of the steel center support, the overall buckling of the inner core is suppressed by peripheral constraints so that it only deforms axially, forming a buckling restrained support composed of peripheral constraints, internal core materials and unbonded materials. However, this support also has problems, such as heavy weight, sliding of peripheral constraints along the length of the component, easy scraping of unbonded materials, high requirements for the plastic deformation capacity of the inner core, and difficulty in detecting inner core damage.

[0003] In the prior art, people in this field have applied origami energy dissipation structures to buckling restraint support devices to improve their performance, but there are still hidden dangers: origami energy dissipation structures with too large slenderness ratios are prone to overall buckling. To address the above problem, professionals have proposed two methods: setting a straight section in the middle of the support and setting a restraint sleeve outside the origami energy dissipation structure, but the results are not ideal.

[0004] In order to solve the above problems, a buckling control brace with a rotationally symmetric cross-section is used. The device consists of an energy dissipation section and two end constraint sections. End plates are respectively provided at both ends of the energy dissipation section, and the two end constraint sections are respectively connected to the two end plates. The origami configuration controls the overall out-of-plane buckling of the component under axial compression, and at the same time enables the support to enter yield along the preset folds along the entire length under the action of the axial load, so that it has good hysteretic energy dissipation capacity. On the one hand, the buckling control brace can avoid the defect of the significant difference in tensile and compressive bearing capacity of ordinary supports. On the other hand, it has the function of a metal damper, which can act as a "fuse" in the structure to protect the main structure from premature destruction under the action of an earthquake. The application of the buckling control brace can comprehensively improve the seismic performance of the braced frame under moderate and large earthquakes, thereby avoiding endangering the lives and property of the residents.

[0005] The above-mentioned buckling control support device has good application prospects and research value. In order to facilitate experimental research on the device before application, it is necessary to prepare a small-scale model of the device. After repeated exploration, the present invention proposes a method for preparing a small-scale model of the device. At present, the preparation methods of origami components mainly include the following categories: ① The preparation method of integral forming by applying external loads. The most typical method is to use customized molds to extrude origami structures. However, the preparation of origami structures of different geometric sizes using this method requires the customization of different molds, which is costly and not suitable for batch preparation of small-scale models of the buckling control support device in the present invention; ② The preparation method using internal stress inconsistency (also called self-folding technology) can make the creases self-fold under external excitation (such as heat, humidity, light, etc.) without the assistance of external loads. However, this method requires strict control of external excitation under laboratory conditions, and the creases need to be made of smart materials such as shape memory alloys and hydrogels, which makes it difficult to meet the needs of the present invention to use common steel materials for batch preparation of small-scale scale models of buckling control support devices; ③ 3D printing metal technology is a rapid prototyping technology, also known as additive manufacturing, which is based on digital model files and uses powdered metals or plastics and other bondable materials to construct objects by printing layer by layer. This technology often causes gaps to form between stacked metal particles, resulting in insufficient density inside the metal, and in particular, the tensile strength of the metal material cannot be guaranteed. In general, the above preparation methods are not suitable for the small-scale scale model of the buckling control support device in the present invention. Taking into account the preparation requirements of the small-scale scale model of the buckling control support device, the present invention proposes a preparation method suitable for the model. Summary of the invention

[0006] In order to solve the above problems, the technical solution adopted by the present invention is:

[0007] A method for preparing a small-scale model of a buckling control support device with a rotationally symmetric cross-section, wherein the small-scale model of the buckling control support device with a rotationally symmetric cross-section comprises an energy-absorbing section, wherein the energy-absorbing section comprises four groups of sub-energy-absorbing sections connected end to end in a circumferential direction, wherein a basic unit after the sub-energy-absorbing sections are flattened comprises two congruent parallelograms connected by overlapping edges, wherein the three sides of the parallelogram in the horizontal direction are divided into two sides of unequal lengths, and the uppermost side and the lowermost side are connected to the overlapping edge by sides of the same length, and finally sixteen sides are formed; in the basic unit after the sub-energy-absorbing sections are flattened, valley folds are made at the fourth side and the eighth side, and peak folds are made at the fifteenth side and the sixteenth side, to form a basic origami unit, and the preparation method comprises the following steps:

[0008] S100, a numerically controlled machine tool cuts a flat steel plate into sub-energy-consuming segments along the fifteenth side and the sixteenth side to form a face group 1 and a face group 2, wherein the face group 1 includes the ninth side, the fifteenth side, the sixteenth side, the thirteenth side, the eighth side, the eleventh side, and the fourth side, and the face group 2 includes the tenth side, the second side, the sixth side, the fourteenth side, the sixteenth side, the twelfth side, and the fifteenth side;

[0009] S200, connecting the face group 1 and the face group 2 in step S100 through the peak line oblique crease to form a sub-energy consumption segment;

[0010] S300, connecting the four groups of sub-energy consuming segments in step S200 along the direction of the eleventh side to form an energy consuming segment with a tubular rotationally symmetrical structure.

[0011] Furthermore, in the step S100, horizontal folds are used inside the surface group 1 and the surface group 2, and the horizontal folds only transmit displacement but do not transmit out-of-plane bending moments.

[0012] Furthermore, the method for preparing the horizontal crease comprises the following steps:

[0013] S110, continuously and evenly drilling a plurality of circular holes on the horizontal folds of the face group 1 and the face group 2;

[0014] S120, locally annealing the horizontal fold of the circular hole with an acetylene flame to compensate for the loss of deformation capacity caused by weakening of the cross section;

[0015] S130, after annealing is completed, the face group 1 and the face group 2 are precisely bent along the horizontal crease to a specified angle by a CNC bending machine.

[0016] Furthermore, in step S200, the peak line oblique crease only transmits displacement but does not transmit out-of-plane bending moment.

[0017] Furthermore, the method for preparing the peak line oblique crease comprises the following steps:

[0018] S210, firstly bend the thinner first connecting member having the first reserved screw guide hole at a specified angle by a CNC bending machine;

[0019] S220, placing two adjacent panels of the face group 1 and the face group 2 with reserved first screw pre-drilled holes in a peak shape, and placing the first connecting member on the peak side;

[0020] S230, disposing a first pad having a second reserved screw guide hole on the peak side of the first connecting member;

[0021] S240. During assembly, an electric drill is used to install the first self-tapping screw from the outside to the inside. The self-tapping screw thread passes through the second reserved screw guide hole of the first pad and the first reserved screw guide hole on the first connecting member in sequence, and forms a drilled hole at the first screw pre-drilled hole on the two adjacent panels of the surface group 1 and the surface group 2, so that the screw thread is tightly engaged with the hole wall of the drilled hole.

[0022] Furthermore, in step S300, the connection between the four groups of sub-energy dissipation segments is a valley line oblique fold, and the valley line oblique fold transmits displacement and out-of-plane bending moment at the same time.

[0023] Furthermore, the method for preparing the valley line oblique crease comprises the following steps:

[0024] S310, firstly bend the thicker second connecting member having the third reserved screw guide hole at a specified angle by a CNC bending machine;

[0025] S320, placing two adjacent panels of the face group 1 and the face group 2 with second screw pre-drilled holes reserved in a valley shape, and placing the second connecting member on the valley side;

[0026] S330, disposing a second pad having a fourth reserved screw guide hole on the valley side of the second connecting member;

[0027] S340. During assembly, use an electric drill to install the second self-tapping screw from the outside to the inside. The self-tapping screw thread passes through the fourth reserved screw guide hole of the second pad and the third reserved screw guide hole of the second connecting member in sequence, and forms a drilled hole at the second screw pre-drilled hole on the two adjacent panels of the surface group one and the surface group two, so that the screw thread is tightly engaged with the wall of the drilled hole.

[0028] Beneficial effects of the present invention:

[0029] (1) Reasonable splitting. Reasonably splitting complex structures into repeated face groups can simplify the preparation of complex structures into simple face groups and connectors, creating conditions for achieving assembly-type preparation.

[0030] (2) An assembled preparation method is implemented to avoid unnecessary stress. The energy dissipation section is composed only of segments and does not require additional filling materials. The energy dissipation section is composed of 8 face groups, which has good forming accuracy and effectively avoids geometric interference and material tearing problems during the preparation process. At the same time, except for the end plate connection, welding is almost not used, avoiding the adverse effects of welding residual stress on the support force.

[0031] (3) An assembly-type preparation method is realized, which is conducive to mass production. By using parts of the same size and specifications, the model production is standardized, the preparation quality of the model is guaranteed, and the preparation efficiency of the model is improved, which provides an important reference for the industrial production of full-scale components with buckling-restrained braces with rotationally symmetric sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 , a schematic diagram of the structure of the present invention;

[0033] Figure 2 , schematic diagram of the segment structure of the energy consumption section;

[0034] Figure 3 , schematic diagram of the basic origami unit structure;

[0035] Figure 4 , schematic diagram of the basic unit structure after flattening;

[0036] Figure 5 , schematic diagram of the structure when the sub-energy consumption section is flattened;

[0037] Figure 6 , schematic diagram of the structure after the sub-energy consumption sections are split;

[0038] Figure 7 , energy consumption segment split diagram;

[0039] Figure 8 , schematic diagram of horizontal creases;

[0040] Fig. 9 , schematic diagram of the splitting and assembly states of the peak line oblique crease;

[0041] Fig.10 , schematic diagram of the splitting and assembly states of the valley line oblique crease;

[0042] Among them, 1. energy absorbing section; 1111. basic origami unit; 2. end constraint section; 3. sub-energy absorbing section; 4. face group one; 5. face group two; 6. horizontal crease; 7. peak line oblique crease; 8. round hole; 9. first screw pre-drilling hole; 10. second screw pre-drilling hole; 11. first connecting piece; 12. first pad; 13. first self-tapping screw; 14. first reserved screw guide hole; 15. second reserved screw guide hole; 16. second connecting piece; 17. second pad; 18. second self-tapping screw; 19. third reserved screw guide hole; 20. fourth reserved screw guide hole; 21. valley line oblique crease. DETAILED DESCRIPTION

[0043] The present invention provides a method for preparing a small-scale model of a buckling control support device with a rotationally symmetrical cross section. The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings to make it easier to understand and grasp.

[0044] refer to Figure 1-10 , a method for preparing a small-scale model of a buckling control support device with a rotationally symmetric cross-section, wherein the small-scale model of the buckling control support device with a rotationally symmetric cross-section includes an energy absorption section 1, end plates connected to both ends of the energy absorption section 1, and end constraint sections 2 connected to the end plates; the energy absorption section 1 includes four groups of sub-energy absorption sections 3 connected end to end in a circumferential direction, and the basic unit of the sub-energy absorption section 3 after being flattened includes two congruent parallelograms connected by overlapping edges, and the three sides of the parallelogram in the horizontal direction are divided into two of unequal lengths, and the uppermost side and the lowermost side are connected to the overlapping side by sides of the same length, and finally sixteen sides are formed.

[0045] like Figure 4 As shown, the shape of the basic unit after the sub-energy consumption segment 3 is flattened is two congruent first parallelograms HAFG and second parallelograms GFEJ. The first side, the second side, the third side and the fourth side of the first parallelogram correspond to the line segments HA, AF, FG and GH respectively, and the fifth side, the sixth side, the seventh side and the eighth side of the second parallelogram correspond to the line segments GF, FE, EJ and JG respectively, wherein the third side coincides with the fifth side, that is, the line segment FG is the line segment GF; point B, point C and point D are located on the line segments HA, FG and EJ respectively, that is, the first side (line segment HA) is divided into the ninth side (line segment HB) and the tenth side (line segment BA) connected to the end of the ninth side (line segment HB), and the third side (line segment FG) is divided into the eleventh side (line segment GC) and the end of the eleventh side (line segment GC). The twelfth side (line segment CF) is connected to the end of the thirteenth side (line segment JD), the seventh side (line segment EJ) is divided into the thirteenth side (line segment JD) and the fourteenth side (line segment DE) connected to the end of the thirteenth side (line segment JD); the lengths of the ninth side (line segment HB), the twelfth side (line segment CF), and the thirteenth side (line segment JD) are respectively greater than the lengths of the tenth side (line segment BA), the eleventh side (line segment GC), and the fourteenth side (line segment DE); the lengths of the ninth side (line segment HB), the twelfth side (line segment CF), and the thirteenth side (line segment JD) are all equal; the ninth side (line segment HB) is connected to the twelfth side (line segment CF) through the fifteenth side (line segment BC), the thirteenth side (line segment JD) is connected to the twelfth side (line segment CF) through the sixteenth side (line segment DC), and the length of the fifteenth side (line segment BC) is equal to the length of the sixteenth side (line segment DC).

[0046] In the basic unit after the sub-energy consumption segment 3 is flattened, valley folds are made at the fourth side (line segment GH) and the eighth side (line segment JG), and peak folds are made at the fifteenth side (line segment BC) and the sixteenth side (line segment DC), forming a basic paper folding unit 1111.

[0047] A method for preparing a small-scale model of a buckling control support device with a rotationally symmetric cross-section comprises the following steps:

[0048] S100, the CNC machine tool cuts the flat steel plate into sub-energy-consuming segments 3 along the fifteenth side (line segment BC) and the sixteenth side (line segment DC), into face group one 4 and face group two 5, face group one 4 includes the ninth side (line segment HB), the fifteenth side (line segment BC), the sixteenth side (line segment DC), the thirteenth side (line segment JD), the eighth side (line segment JG), the eleventh side (line segment GC), and the fourth side (line segment GH), face group two 5 includes the tenth side (line segment BA), the second side (line segment AF), the sixth side (line segment FE), the fourteenth side (line segment DE), the sixteenth side (line segment DC), the twelfth side (line segment CF), and the fifteenth side (line segment BC), and the interiors of face group one 4 and face group two 5 are both provided with horizontal folds 6, and the horizontal folds 6 only transmit displacement but not out-of-plane bending moment;

[0049] like Figure 8 As shown, the method for preparing the horizontal fold 6 comprises the following steps:

[0050] S110, continuously and evenly drilling a plurality of circular holes 8 on the horizontal folds 6 on the face group 1 4 and the face group 2 5;

[0051] S120, locally annealing the horizontal fold 6 of the circular hole 8 with an acetylene flame to compensate for the loss of deformation capacity caused by the weakening of the cross section;

[0052] S130, after annealing is completed, the face group 1 4 and the face group 2 5 are precisely bent along the horizontal crease 6 to a specified angle by a CNC bending machine;

[0053] S200, connecting the face group 1 4 and the face group 2 5 in step S100 through the peak line oblique fold 7 to form a sub-energy dissipation section 3, wherein the peak line oblique fold 7 only transmits displacement but does not transmit out-of-plane bending moment;

[0054] like Fig. 9 As shown, the method for preparing the peak line oblique fold 7 comprises the following steps:

[0055] S210, firstly bend the thinner first connecting member 11 having the first reserved screw guide hole 14 at a specified angle by a CNC bending machine;

[0056] S220, placing two adjacent panels of the face group 1 4 and the face group 2 5 with the first screw pre-drilled holes 9 reserved in a peak shape, and placing the first connecting member 11 on the peak side;

[0057] S230, disposing a first pad 12 having a second reserved screw guide hole 15 on the peak side of the first connecting member 11;

[0058] S240, during assembly, the first self-tapping screw 13 is installed from the outside to the inside with an electric drill, and the self-tapping screw thread passes through the second reserved screw guide hole 15 of the first pad 12 and the first reserved screw guide hole 14 on the first connecting member 11 in sequence, and forms a drilled hole at the first screw pre-drilled hole 9 on the two adjacent panels of the face group 1 4 and the face group 2 5, so that the screw thread is tightly engaged with the hole wall of the drilled hole, and under the tightening action of the first self-tapping screw 13 and the panel, the first connecting member 11 and the first pad 12 between the two are fixed, forming a peak line oblique fold;

[0059] S300, connecting the four groups of sub-energy absorbing segments 3 in step S200 along the direction of the eleventh side (line segment GC) to form an energy absorbing segment with a tubular rotationally symmetrical structure, wherein the four groups of sub-energy absorbing segments 3 are connected by valley line oblique folds 21, and the valley line oblique folds 21 simultaneously transmit displacement and out-of-plane bending moment.

[0060] like Fig.10 As shown, the method for preparing the valley line oblique crease 21 comprises the following steps:

[0061] S310, firstly bend the thicker second connecting member 16 having the third reserved screw guide hole 19 at a specified angle by a CNC bending machine;

[0062] S320, placing two adjacent panels of the face group 1 4 and the face group 2 5 with the second screw pre-drilled holes 10 reserved in a valley shape, and placing a second connecting member 16 on the valley side;

[0063] S330, disposing a second pad 17 having a fourth reserved screw guide hole 20 on the valley side of the second connecting member 16;

[0064] S340. During assembly, use an electric drill to install the second self-tapping screw 18 from the outside to the inside. The self-tapping screw thread passes through the fourth reserved screw guide hole 20 of the second pad 17 and the third reserved screw guide hole 19 of the second connecting member 16 in sequence, and forms a drilled hole at the second screw pre-drilled hole 10 on the two adjacent panels of the face group 1 4 and the face group 2 5, so that the screw thread is tightly engaged with the wall of the drilled hole. Under the tightening action of the second self-tapping screw 18 and the panel, the second connecting member 16 and the second pad 17 between the two are fixed, forming a valley line oblique fold.

[0065] The above fully describes the technical solution of the present invention. It should be noted that the specific implementation of the present invention is not limited to the above description. All technical solutions formed by ordinary technicians in the field using equivalent or equivalent transformations in structure, method or function based on the spirit of the present invention fall within the protection scope of the present invention.

Claims

1. A method for preparing a small-scale model of a buckling control support device with a rotationally symmetric cross-section, wherein: The small-scale model of the buckling control support device with a rotationally symmetric cross-section includes an energy-absorbing section, and the energy-absorbing section includes four groups of sub-energy-absorbing sections connected end to end in a circumferential direction. The basic unit of the sub-energy-absorbing section after being flattened includes two congruent parallelograms connected by overlapping edges, and the three sides of the parallelogram in the horizontal direction are divided into two of unequal lengths, and the uppermost side and the lowermost side are connected to the overlapping edge by sides of the same length, and finally sixteen sides are formed; the shape of the basic unit of the sub-energy-absorbing section after being flattened is two congruent first parallelograms HAFG, a second parallelogram The first parallelogram has a first side, a second side, a third side and a fourth side, which correspond to line segments HA, AF, FG and GH respectively. The fifth side, the sixth side, the seventh side and the eighth side, which correspond to line segments GF, FE, EJ and JG respectively, are quadrilaterals GFEJ. Point B, point C and point D are located on line segments HA, FG and EJ respectively. That is, the first side - line segment HA is divided into the ninth side - line segment HB and the tenth side connected to the end of the ninth side - line segment HB. The third side-line segment FG is divided into the eleventh side-line segment GC and the twelfth side-line segment CF connected to the end of the eleventh side-line segment GC, the seventh side-line segment EJ is divided into the thirteenth side-line segment JD and the fourteenth side-line segment DE connected to the end of the thirteenth side-line segment JD; the lengths of the ninth side-line segment HB, the twelfth side-line segment CF, and the thirteenth side-line segment JD are respectively greater than the lengths of the tenth side-line segment BA, the eleventh side-line segment GC, and the fourteenth side-line segment DE; the ninth side-line segment HB, the twelfth side-line segment CF, and the thirteenth side-line segment The lengths of JD are all equal; the ninth side-line segment HB is connected to the twelfth side-line segment CF through the fifteenth side-line segment BC, the thirteenth side-line segment JD is connected to the twelfth side-line segment CF through the sixteenth side-line segment DC, and the length of the fifteenth side-line segment BC is equal to the length of the sixteenth side-line segment DC; in the basic unit after the sub-energy consumption segment is flattened, the fourth side-line segment GH and the eighth side-line segment JG are valley folded, and the fifteenth side-line segment BC and the sixteenth side-line segment DC are peak folded to form a basic paper folding unit, characterized in that the preparation method comprises the following steps: S100, a numerically controlled machine tool cuts a flat steel plate into sub-energy-consuming segments along the fifteenth side and the sixteenth side to form a face group 1 and a face group 2, wherein the face group 1 includes the ninth side, the fifteenth side, the sixteenth side, the thirteenth side, the eighth side, the eleventh side, and the fourth side, and the face group 2 includes the tenth side, the second side, the sixth side, the fourteenth side, the sixteenth side, the twelfth side, and the fifteenth side; S200, connecting the face group 1 and the face group 2 in step S100 through the peak line oblique crease to form a sub-energy consumption segment; S300, connecting the four groups of sub-energy-consuming segments in step S200 along the direction of the eleventh side to form an energy-consuming segment with a tubular rotationally symmetrical structure; In the step S100, horizontal folds are used inside the surface group 1 and the surface group 2, and the horizontal folds only transmit displacement but do not transmit out-of-plane bending moments; The method for preparing the horizontal crease comprises the following steps: S110, continuously and evenly drilling a plurality of circular holes on the horizontal folds of the face group 1 and the face group 2; S120, locally annealing the horizontal fold of the circular hole with an acetylene flame to compensate for the loss of deformation capacity caused by weakening of the cross section; S130, after annealing is completed, the face group 1 and the face group 2 are precisely bent along the horizontal crease to a specified angle by a CNC bending machine; In the step S200, the peak line oblique crease only transmits displacement but does not transmit out-of-plane bending moment; The method for preparing the peak line oblique crease comprises the following steps: S210, firstly bend the first connecting member having the first reserved screw guide hole according to a specified angle by a CNC bending machine; S220, placing two adjacent panels of the face group 1 and the face group 2 with reserved first screw pre-drilled holes in a peak shape, and placing the first connecting member on the peak side; S230, disposing a first pad having a second reserved screw guide hole on the peak side of the first connecting member; S240, during assembly, the first self-tapping screw is installed from the outside to the inside using an electric drill, the self-tapping screw thread sequentially passes through the second reserved screw guide hole of the first pad and the first reserved screw guide hole on the first connecting member, and forms a drilled hole at the first screw pre-drilled hole on two adjacent panels of the face group 1 and the face group 2, so that the screw thread is tightly engaged with the hole wall of the drilled hole; In the step S300, the connection between the four groups of sub-energy dissipation segments is a valley line oblique fold, and the valley line oblique fold transmits displacement and out-of-plane bending moment at the same time; The method for preparing the valley line oblique crease comprises the following steps: S310, firstly bend the second connecting member having the third reserved screw guide hole according to a specified angle by a CNC bending machine; S320, placing two adjacent panels of the face group 1 and the face group 2 with second screw pre-drilled holes reserved in a valley shape, and placing the second connecting member on the valley side; S330, disposing a second pad having a fourth reserved screw guide hole on the valley side of the second connecting member; S340. During assembly, use an electric drill to install the second self-tapping screw from the outside to the inside. The self-tapping screw thread passes through the fourth reserved screw guide hole of the second pad and the third reserved screw guide hole of the second connecting member in sequence, and forms a drilled hole at the second screw pre-drilled hole on the two adjacent panels of the surface group one and the surface group two, so that the screw thread is tightly engaged with the wall of the drilled hole.

Images