Support negative bending moment peak shaving device and parameter determination method thereof

Abstract

The application provides a support negative bending moment peak clipping device, belonging to the technical field of building curtain wall structure, comprising two pieces of peak clipping steel sheets, which are arranged on the two sides of a stand column; the peak clipping steel sheet comprises a fixed section and a connecting section, the fixed section is fastened and clamped on the two sides of the stand column through a first pair of through bolts, a second pair of through bolts and a third pair of through bolts; the shaft center of the first pair of through bolts, the shaft center of the second pair of through bolts and the shaft center of the third pair of through bolts are located on the same vertical line parallel to the axial direction of the stand column; the upper and lower ends of the fixed section are gradually narrowed towards the middle part of the fixed section and protrude out of the stand column to form the connecting section, the connecting section is connected with a support adapter at the building main structure; the top end of the stand column is provided with an upper support, and the bottom end of the stand column is provided with a lower support; the upper support and the lower support are connected with the building main structure respectively; the support negative bending moment peak clipping device is arranged between the upper support and the lower support. The application can significantly reduce the negative bending moment of the middle support of the stand column.

Description

Technical Field

[0001] This invention belongs to the field of building curtain wall structure technology, and specifically relates to a support negative bending moment peak reduction device and its parameter determination method. Background Technology

[0002] As the main vertical load-bearing components of curtain walls, curtain wall mullions often adopt a double-span or multi-span continuous support configuration. Significant negative bending moment peaks occur at the intermediate support locations, which are typically much larger than the positive bending moment at mid-span. This is a key stress indicator controlling the selection of mullion cross-sections. During the design phase of a new curtain wall, designers will perform cross-section verification based on the prevailing load specifications, estimated loads, and the factory mechanical properties of the aluminum profiles to ensure that the negative bending moment at the mullion supports does not exceed the design ultimate bearing capacity of the profiles.

[0003] However, after existing curtain walls have been in service for a long time, multiple adverse changes will occur, resulting in a significant reduction in the original safety reserve of the columns and even the risk of exceeding the negative bending moment limit of the supports: First, aluminum profiles are exposed to outdoor temperature changes, rain, and ultraviolet corrosion for a long time, causing a continuous decline in mechanical properties, a decrease in the yield strength and effective bearing capacity of the sections, and the current actual ultimate bending moment that the columns can withstand is far lower than the value designed at the beginning of construction; Second, during the project's use phase, modifications and additional loads are added, such as the installation of billboards, sunshade louvers, equipment pipelines, etc. on the facade, which significantly increases the actual self-weight load borne by the curtain wall; Third, some curtain walls have been in use for a long time, and changes in the use function of each section and the addition of auxiliary components have led to a significant deviation between the actual stress conditions of the columns and the new design model.

[0004] Existing conventional reinforcement methods for addressing excessive negative bending moments at column supports fall into two categories: one is to increase the cross-section of the column aluminum profile or to add steel inserts along the entire length of the column for local reinforcement. However, the internal cavity of the unitized curtain wall column is narrow, limiting the installation space for the steel inserts. Furthermore, the material consumption for the continuous inserts is large, and the processing and on-site installation procedures are cumbersome. The other is to replace the entire curtain wall column, which is costly, has a long construction period, and can also significantly impact the normal use of the building.

[0005] For the aforementioned renovation scenarios where old curtain wall columns have insufficient load-bearing capacity and excessive negative bending moment at the supports after service, existing reinforcement solutions suffer from drawbacks such as high material consumption, difficult construction, high renovation costs, and poor adaptability. Currently, there is a lack of a simple, easy-to-install, and precisely controllable reinforcement device that can precisely adjust the peak value of the negative bending moment at the supports, as well as a complete method for quantitatively determining parameters. This device should be able to accurately calculate the device dimensions by combining the measured remaining mechanical properties of the columns with the current actual load, thus balancing structural safety, ease of construction, and engineering economy. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a support negative bending moment peak reduction device and a method for determining its parameters.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: a support negative bending moment peak reduction device, comprising: Two shaped steel plates are disposed on both sides of the column; each shaped steel plate includes a fixed section and a connecting section. The fixed section is fastened and clamped to both sides of the column by a first through bolt, a second through bolt, and a third through bolt; the axes of the first through bolt, the second through bolt, and the third through bolt are located on the same vertical line parallel to the axis of the column. The upper and lower ends of the fixed section gradually narrow towards the middle of the fixed section and protrude from the column to form the connecting section, which is connected to the supporting transition piece at the main structure of the building. The top of the column is provided with an upper support, and the bottom of the column is provided with a lower support; the upper support and the lower support are respectively connected to the main structure of the building; the negative bending moment reduction device of the support is provided between the upper support and the lower support.

[0008] Furthermore, the support negative bending moment reduction device also includes: Two horizontal elongated holes are provided through the surface of the connecting section; Two vertical short holes are provided through the end of the support adapter, which is a support steel bracket welded to the embedded plate of the main building structure. The extension direction of the two vertical short holes is perpendicular to the extension direction of the two horizontal long holes. The two vertical short holes correspond to and are connected to the two horizontal long holes. Two fourth through bolts, the threaded ends of which pass through two horizontal long holes and two vertical short holes in sequence; the straight line formed by the axes of the two fourth through bolts is parallel to the vertical line.

[0009] Furthermore, the support negative bending moment reduction device also includes: A steel washer; the steel washer is placed between the connecting section and the bolt head of the fourth through bolt, and the surface of the steel washer is provided with a through hole for the fourth through bolt to pass through.

[0010] Furthermore, the horizontal elongated hole is arranged perpendicular to the axial direction of the column, and the horizontal elongated hole allows the fourth through bolt to slide along its length to adjust the distance between the supporting steel bracket and the column.

[0011] Furthermore, the vertical short holes are arranged in a direction parallel to the column axis, and the supporting steel bracket slides along the column axis relative to the fourth through bolt through the vertical short holes, thereby adjusting the vertical installation elevation of the supporting steel bracket relative to the column.

[0012] Furthermore, the surface of the connecting section is provided with a slot that extends along the axial direction of the column; the supporting adapter is a hanging shaft pre-embedded in the main structure of the building, and the slot is engaged with the outside of the hanging shaft.

[0013] A method for determining parameters of a support negative bending moment peak reduction device, the method being applied to the aforementioned support negative bending moment peak reduction device, comprising: Obtain the measured verification foundation parameters of the column, the ultimate bending moment that the column section can currently withstand, the project steel cost control threshold, the unit cost of steel, and the maximum allowable assembly space for the spacing of the first and third through bolts; the measured verification foundation parameters include the measured cross-sectional dimensions of the column, the remaining mechanical properties of the column after long-term service, the existing curtain wall panel dimensions, wind load, self-weight load, and the additional load currently actually acting on the column; Based on the measured verification parameters, a first finite element verification model of the peak-shaving device was established, and the maximum negative bending moment of the support at the middle support position and the distribution diagram of the column bending moment of the peak-shaving device under the current service status of the curtain wall were obtained. When the maximum negative bending moment of the middle support position of the curtain wall under the current service status is greater than the ultimate bending moment that the column section can currently withstand, the preliminary values ​​of the spacing between the first and third through bolts are obtained according to the bending moment distribution diagram of the column without the peak-cutting device. Based on the preliminary values ​​of the spacing between the first and third through bolts and the measured verification base parameters, a second finite element verification model with the peak-shaving device is established to obtain the maximum negative bending moment of the support with the peak-shaving device. Based on the maximum negative bending moment of the support equipped with the peak-shaving device and the current ultimate bending moment that the column section can withstand, the minimum value of the spacing between the first and third through bolts is obtained. Based on the project's steel cost control threshold and the unit cost of steel, the upper limit of the spacing between the first and third through bolts allowed by the total cost of steel is obtained; Based on the minimum value of the spacing between the first and third through bolts, the upper limit of the spacing between the first and third through bolts allowed by the total cost of steel, and the maximum allowable assembly space for the spacing between the first and third through bolts, the effective range of values ​​for the spacing between the first and third through bolts is obtained. Based on the effective range of the spacing between the first and third through bolts, determine the reference values ​​of the spacing between the first and third through bolts, as well as the initial distance between the installation point of the connecting section and the support adapter and the spacing between the third through bolts. Based on the reference values ​​of the spacing between the first and third through bolts, the installation point of the connecting section and the support adapter, the initial distance of the spacing between the third through bolts, and the measured verification basic parameters, a third finite element verification model equipped with the peak-shaving device is established to obtain the upper peak bending moment and lower peak bending moment of the connecting section of the peak-shaving device. Based on the peak bending moment at the upper end and the peak bending moment at the lower end of the connecting section of the peak shaving device, the allowable deviation and the bending moment difference between the upper and lower ends of the connecting section of the peak shaving device are obtained. Based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section of the peak-shaving device, the target distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt is obtained.

[0014] Furthermore, when the maximum negative bending moment at the support position of the curtain wall under its current service condition is greater than the ultimate bending moment that the column section can currently withstand, the preliminary values ​​of the spacing between the first and third through bolts are obtained based on the column bending moment distribution diagram without the peak-cutting device, including: Draw a reference straight line parallel to the column axis in the bending moment distribution diagram of the column without the peak-cutting device. Translate the reference straight line in the direction of decreasing bending moment value until the bending moment values ​​corresponding to the two intersection points of the reference straight line and the negative bending moment curve of the support are equal to the current ultimate bending moment that the column section can withstand. Take the distance between the two intersection points as the initial value of the spacing between the first and third through bolts.

[0015] Furthermore, based on the project's steel cost control threshold and unit steel cost, the upper limit of the spacing between the first and third through bolts, which is allowed by the total steel cost, is obtained, including: Based on the project's steel cost control threshold and unit steel cost, the maximum allowable steel usage for the support negative moment peak-shaving device is calculated. Under the premise that the cross-sectional specifications of the support negative moment peak-shaving device remain unchanged, a correspondence is established between the spacing of the first and third through bolts and the theoretical steel usage of the support negative moment peak-shaving device. Based on the maximum steel usage and the correspondence between the spacing of the first and third through bolts and the theoretical steel usage of the support negative moment peak-shaving device, the upper limit of the spacing between the first and third through bolts, which is allowed by the total steel cost, is calculated.

[0016] Furthermore, based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section of the peak-shaving device, the target distances between the installation point of the connecting section and the support adapter and the spacing of the third through bolts are obtained, including: When the difference in bending moment between the upper and lower ends of the connecting section of the peak-shaving device is greater than the allowable deviation, the reference values ​​of the spacing between the first and third through bolts are kept unchanged. The initial distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt is adjusted to obtain the adjustment distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt. Based on the reference values ​​of the spacing between the first and third through bolts, the adjustment distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt, and the measured verification basic parameters, a third finite element verification model equipped with the peak-shaving device is established until the difference in bending moment between the upper and lower ends of the connecting section of the peak-shaving device is less than the allowable deviation. The corresponding adjustment distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt is taken as the target distance between the installation point of the connecting section and the support adapter and the spacing of the third through bolt.

[0017] The above-described solution of the present invention has at least the following beneficial effects: The above-mentioned solution of this invention addresses the problems of deterioration in the mechanical properties of existing curtain wall columns due to long-term service, increased additional loads, and excessive negative bending moments at the central supports caused by updates to current load standards. It provides two connection structures adapted to different curtain wall types and offers a complete method for determining quantitative parameters. Overall, it has many significant advantages over traditional column reinforcement methods. By expanding the vertical support range of the central supports of the columns using peak-cutting steel components, the bending moment of the column section can be adjusted to meet the current limits of the curtain wall structure bearing capacity specifications by adjusting the spacing between the first and third through bolts.

[0018] This invention provides two interchangeable main connection structures to adapt to both frame curtain wall and unitized curtain wall projects. The frame curtain wall uses supporting steel brackets connected with fourth through bolts, relying on horizontal long holes and vertical short holes to achieve bidirectional adjustment of the horizontal spacing and vertical installation elevation of the columns, which can offset the dimensional deviations caused by on-site processing and installation. The unitized curtain wall uses a slot and main body hanging shaft to engage, eliminating the need to add inserts to the inner cavity of the columns, thus avoiding the defects of small internal space of unitized columns, difficulty in insert installation, and obstacles to the assembly of unitized panels. The same set of peak-cutting steel main structure is compatible with two mainstream curtain wall systems, eliminating the need to customize reinforcement components for different curtain walls, and significantly improving the versatility of projects.

[0019] The method for determining the supporting parameters of this invention incorporates the dual constraints of assembly space boundaries and steel cost, eliminating the need for unlimited lengthening of steel components to create excessive safety redundancy. It controls steel consumption while ensuring the column's load-bearing capacity meets standards. Compared to traditional continuous steel core reinforcement schemes for column cavities, this significantly reduces steel usage, effectively lowering component processing and material procurement costs, and achieving a balance between structural safety and engineering economy. During on-site renovation and construction, only three pairs of through bolts are used to clamp and fix the peaked steel components to both sides of the column, eliminating the need for cutting or enlarging holes to damage the original curtain wall column profile. This does not damage the original curtain wall's main load-bearing structure, simplifying the on-site assembly process, eliminating the need for large-scale removal of curtain wall panels, minimizing disruption to daily building use, and resulting in a shorter overall construction cycle and lower labor costs. Attached Figure Description

[0020] Figure 1 This is a structural schematic diagram of a frame curtain wall column equipped with the support negative bending moment peak reduction device of Embodiment 1 of the present invention; Figure 2 This is a three-dimensional structural schematic diagram of the support negative bending moment peak reduction device according to Embodiment 1 of the present invention; Figure 3 An exploded structural diagram of the support negative bending moment peak reduction device according to Embodiment 1 of the present invention; Figure 4 This is a partial structural diagram of a frame curtain wall column equipped with the support negative bending moment peak reduction device of Embodiment 1 of the present invention; Figure 5 This is a partial structural diagram of a unit curtain wall column equipped with the support negative bending moment peak reduction device of Embodiment 2 of the present invention; Figure 6 This is a bending moment distribution diagram of a column without the support negative bending moment peak reduction device of the present invention; Figure 7 This is a diagram showing the bending moment distribution of the column after the support negative bending moment reduction device of the present invention has been installed.

[0021] Figure label: 1. Shaving steel sheet; 2. Column; 3. Fixing section; 4. Connecting section; 5. First through bolt; 6. Second through bolt; 7. Third through bolt; 8. Support adapter; 9. Upper support; 10. Lower support; 11. Horizontal long hole; 12. Vertical short hole; 13. Fourth through bolt; 14. Steel washer; 15. Slot. Detailed Implementation

[0022] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0023] Example 1 like Figures 1 to 4 As shown, an embodiment of the present invention provides a support negative bending moment peak reduction device, comprising: Two shaving steel plates 1 are respectively disposed on both sides of the column 2; each shaving steel plate 1 includes a fixing section 3 and a connecting section 4. The fixing section 3 is fastened and clamped to both sides of the column 2 by a first through bolt 5, a second through bolt 6 and a third through bolt 7; the axis of the first through bolt 5, the axis of the second through bolt 6 and the axis of the third through bolt 7 are located on the same vertical line parallel to the axis of the column 2. The upper and lower ends of the fixed section 3 gradually narrow towards the middle of the fixed section 3 and protrude from the column 2 to form the connecting section 4. The connecting section 4 is connected to the support adapter 8 at the main structure of the building. The top of the column 2 is provided with an upper support 9, and the bottom of the column 2 is provided with a lower support 10; the upper support 9 and the lower support 10 are respectively connected to the main structure of the building; the support negative bending moment peak reduction device is provided between the upper support 9 and the lower support 10.

[0024] Furthermore, the support negative bending moment reduction device also includes: Two horizontal elongated holes 11 are provided through the surface of the connecting section 4; Two vertical short holes 12 are provided through the end of the support adapter 8. The support adapter 8 is a support steel bracket welded to the embedded plate of the main building structure. The extension direction of the two vertical short holes 12 is perpendicular to the extension direction of the two horizontal long holes 11. The two vertical short holes 12 correspond to and are connected to the two horizontal long holes 11. Two fourth through bolts 13, the threaded ends of the two fourth through bolts 13 passing through two horizontal long holes 11 and two vertical short holes 12 in sequence; the straight line formed by the axes of the two fourth through bolts 13 is parallel to the vertical line.

[0025] When carrying out safety review and reinforcement renovation of existing old curtain walls, on-site measurement and stress verification were conducted on column 2, and it was determined that the support negative bending moment peak reduction device of the present invention needs to be installed for reinforcement.

[0026] During on-site assembly, two sheared steel plates 1 are respectively attached to the corresponding outer walls on both sides of the column 2. The first through bolt 5 and the third through bolt 7 are sequentially passed through the sheared steel plate 1 on one side, the corresponding load-bearing bolt hole on the column 2, and the sheared steel plate 1 on the other side to complete the locking installation. The first through bolt 5 and the third through bolt 7 serve as the main load-bearing connecting components, bearing the transmission of bending moment and shear force between the sheared steel plate 1 and the column 2. The second through bolt 6 is sequentially passed through the sheared steel plate 1 on one side, the corresponding structural bolt hole on the column 2, and the sheared steel plate 1 on the other side for assembly. The second through bolt 6 plays an auxiliary clamping and limiting role, preventing the middle of the sheared steel plate 1 from warping or detaching from the surface of the column 2. After assembly, a gap is formed between the two sheared steel plates 1, allowing the original central support to extend and avoid it. The original central support of the column 2 is located within the gap formed by the two sheared steel plates 1, eliminating the need to remove the original central support, and the components do not interfere with each other.

[0027] The supporting steel bracket is a new component added during the renovation construction phase. It is pre-welded and fixed to the embedded plate of the main building structure. The end of the supporting steel bracket extends into the gap formed by the connecting section 4 of the two peaked steel plates 1 and fits together with each other in the connecting section 4. The operator inserts two fourth through bolts 13 through the horizontal long hole 11 of one side of the peaked steel plate 1, the vertical short hole 12 of the supporting steel bracket, and the horizontal long hole 11 of the peaked steel plate 1 on the other side and locks them. The peaked device is used to widen the effective vertical support range of the column 2 and reduce the peak negative bending moment at the support position in the column 2.

[0028] Please see Figure 6 and Figure 7 , Figure 6 The diagram shows the bending moment distribution of a column without the support negative bending moment reduction device of the present invention. The load of column 2 is concentrated on the original middle support point of column 2, which will generate a concentrated negative bending moment with a large amplitude at the middle support position. After the support negative bending moment reduction device is installed, the force range is extended vertically by relying on the peak reduction steel plate 1. The negative bending moment that was originally concentrated at a single point is dispersed to a vertical range, and the peak negative bending moment is significantly reduced, thus achieving the peak reduction effect of negative bending moment.

[0029] It should be noted that this embodiment is adapted to the renovation of frame curtain walls. The frame curtain wall column 2 does not have a pre-embedded hanging shaft structure for the unit curtain wall column 2. Therefore, the assembly method of adding supporting steel brackets on site is adopted. The whole device does not need to modify the original frame curtain wall column 2 and the main structure of the central support. The stress optimization is achieved only by clamping the peaked steel sheet 1 on the outside of the column 2. The construction is convenient and can effectively reduce the damage to the original curtain wall facade caused by the renovation construction.

[0030] Furthermore, the horizontal elongated hole 11 is arranged perpendicular to the axial direction of the column 2. The horizontal elongated hole 11 allows the fourth through bolt 13 to slide along its length to adjust the distance between the supporting steel bracket and the column 2.

[0031] Furthermore, the vertical short hole 12 is arranged in a direction parallel to the axial direction of the column 2, and the supporting steel bracket slides relative to the fourth through bolt 13 along the axial direction of the column 2 through the vertical short hole 12, thereby adjusting the vertical installation elevation of the supporting steel bracket relative to the column 2.

[0032] Please see Figures 2 to 3 The horizontal long hole 11 provides horizontal adjustment margin to ensure smooth alignment and assembly of the peak-cutting steel sheet 1 and the supporting steel bracket; the vertical short hole 12 provides vertical elevation adjustment margin for the supporting steel bracket. The two together form a two-way adjustable installation structure, reducing the difficulty of bolt hole alignment on site and improving the error tolerance rate of the renovation construction.

[0033] Furthermore, the support negative bending moment reduction device also includes: Steel washer 14; the steel washer 14 is placed between the bolt head of the connecting section 4 and the fourth through bolt 13, and the surface of the steel washer 14 is provided with a through hole for the fourth through bolt 13 to pass through.

[0034] Please see Figures 2 to 4 The steel washer 14 can increase the bearing contact area between the bolt head of the fourth through bolt 13 and the connecting section 4 of the shaving steel plate 1, disperse the bolt pre-tightening pressure, and avoid local damage to the shaving steel plate 1 by the bolt head during the tightening process; at the same time, it can seal the gap of the horizontal elongated hole 11, restrict the fourth through bolt 13 from accidentally slipping in the horizontal elongated hole 11, ensure the long-term stability of the connection position, and improve the stress reliability of the entire connection node.

[0035] Example 2 Furthermore, a slot 15 is provided through the surface of the connecting section 4, and the slot 15 extends along the axial direction of the column 2; the supporting adapter 8 is a hanging shaft pre-embedded in the main structure of the building, and the slot 15 is engaged with the outside of the hanging shaft.

[0036] Please see Figure 5Compared to Embodiment 1, this embodiment is adapted to the renovation scenario of unitized curtain walls. The unitized curtain wall is pre-installed with embedded hanging shafts during the factory prefabrication stage to connect the unit panels to the main structure. Therefore, there is no need to add on-site welded support steel brackets, fourth through bolts 13, steel washers 14, or other connecting components. The existing hanging shafts of the unitized curtain wall are directly used as support adapters 8. During assembly, simply insert the slots 15 of the peak-cutting steel sheet 1 connecting section 4 into the hanging shaft from top to bottom to complete the alignment connection. Long hole adjustment and bolt insertion and tightening processes are no longer required. The assembly method of the two peak-cutting steel sheets 1 clamping the column 2, the spatial avoidance relationship between new and old components, and the working principle of negative bending moment peak cutting are consistent with Embodiment 1. Identical structural components will not be repeated. The unitized curtain wall has a built-in embedded hanging shaft structure, which forms a snap-fit ​​connection with the hanging shaft using the slots 15, greatly simplifying the on-site construction process, avoiding on-site hot work welding, and shortening the renovation period.

[0037] It should be noted that the greater the length of the negative moment reduction device along the axial direction of column 2, the more significant the reduction effect of the negative moment on the intermediate support. However, when the device length exceeds a certain critical value, the reduction effect no longer improves significantly with increasing length, while the material consumption, processing, and installation costs of the reduction steel sheet 1 continue to rise. Therefore, it is necessary to determine the effective range of the length of the negative moment reduction device along the axial direction of column 2 while meeting the safety control requirements of the bearing capacity of column 2 and taking into account the economic efficiency of the project, so as to achieve a balance between structural safety and modification costs.

[0038] Embodiments of the present invention also propose a method for determining the parameters of a support negative bending moment peak reduction device. This method is applied to the aforementioned support negative bending moment peak reduction device and includes: Step 100: Obtain the measured verification foundation parameters of column 2, the ultimate bending moment that the column 2 section can currently withstand, the project steel cost control threshold, the unit cost of steel, and the maximum allowable assembly space for the spacing between the first through bolt 5 and the third through bolt 7; the measured verification foundation parameters include the measured cross-sectional dimensions of column 2, the remaining mechanical properties of column 2 after long-term service, the existing curtain wall panel dimensions, wind load, self-weight load, and the additional load currently actually acting on column 2; Step 101: Based on the measured verification basic parameters, establish the first finite element verification model of the peak-shaving device, and obtain the maximum negative bending moment of the support at the middle support position and the bending moment distribution diagram of the column 2 without the peak-shaving device under the current service status of the curtain wall. Step 102: When the maximum negative bending moment of the support at the middle support position under the current service status of the curtain wall is greater than the current ultimate bending moment that the column 2 section can withstand, the preliminary values ​​of the spacing between the first through bolt 5 and the third through bolt 7 are obtained according to the bending moment distribution diagram of the column 2 without the peak-cutting device. Step 103: Based on the preliminary values ​​of the spacing between the first through bolt 5 and the third through bolt 7 and the measured verification basic parameters, establish a second finite element verification model with the peak-shaving device, and obtain the maximum negative bending moment of the support with the peak-shaving device. Step 104: Based on the maximum negative bending moment of the support equipped with the peak-shaving device and the current ultimate bending moment that the column 2 section can withstand, obtain the minimum value of the spacing between the first through bolt 5 and the third through bolt 7. Step 105: Based on the project's steel cost control threshold and the unit cost of steel, obtain the upper limit of the spacing between the first through bolt 5 and the third through bolt 7, which is allowed by the total cost of steel. Step 106: Based on the minimum value of the spacing between the first through bolt 5 and the third through bolt 7, the upper limit of the spacing between the first through bolt 5 and the third through bolt 7 allowed by the total cost of steel, and the maximum allowable assembly space for the spacing between the first through bolt 5 and the third through bolt 7, the effective range of values ​​for the spacing between the first through bolt 5 and the third through bolt 7 is obtained. Step 107: Based on the effective range of the spacing between the first through bolt 5 and the third through bolt 7, determine the reference value of the spacing between the first through bolt 5 and the third through bolt 7, as well as the initial distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7. Step 108: Based on the reference value of the spacing between the first through bolt 5 and the third through bolt 7, the installation point of the connecting section 4 and the support adapter 8, the initial distance of the spacing between the third through bolt 7, and the measured verification basic parameters, establish a third finite element verification model equipped with the peak reduction device, and obtain the upper peak bending moment and lower peak bending moment of the connecting section 4 of the peak reduction device. Step 109: Based on the upper peak bending moment and lower peak bending moment of the connecting section 4 of the peak-shaving device, obtain the allowable deviation and the bending moment difference between the upper and lower ends of the connecting section 4 of the peak-shaving device. Step 110: Based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section 4 of the peak-shaving device, obtain the target distance between the installation point of the connecting section 4 and the support adapter 8 and the distance between the third through bolt 7.

[0039] In this embodiment, the actual cross-sectional dimensions of column 2 can be obtained on-site by using vernier calipers and laser rangefinders. The remaining mechanical properties of column 2 after long-term service can be determined by combining on-site non-destructive testing with durability attenuation calculation. For example, ultrasonic non-destructive testing can be used to detect corrosion depth, internal microcracks and other damage defects in column 2 to quantify the damage level of the component. Then, combined with the actual service life of the curtain wall and the atmospheric corrosion environment conditions of the project, a material strength attenuation model is used for correction calculation. The damage reduction coefficient is introduced to obtain the current effective yield strength, effective elastic modulus and other remaining mechanical indicators of the profile, which are used as input parameters for the material constitutive model of the finite element model. The existing curtain wall panel dimensions, wind load, self-weight load, and additional loads currently acting on column 2 are determined comprehensively based on on-site measurements, verification of the original building as-built drawings, and current load specifications. The curtain wall panel dimensions are obtained through on-site measurements of the beams, column 2 spacing, and panel dimensions. The self-weight load is calculated based on the actual specifications and thickness of the existing glass panels, aluminum profiles, decorative covers, and auxiliary components. The wind load is strictly calculated in accordance with current building structure load specifications, combined with parameters such as basic wind pressure, building height, shape coefficient, and wind vibration coefficient at the project site. The additional loads are statistically summarized by on-site verification of the current working conditions of the facade, including newly added louvers, advertising components, maintenance facilities, and loads added during later renovations, ultimately forming a complete set of load input parameters that accurately reflect the current service status of the curtain wall. The ultimate bending moment that column section 2 can currently withstand is determined based on the section's geometric parameters and the previously obtained effective yield strength of the profile. The calculation formula is as follows: M0=W nx ×f; Where M0 is the ultimate bending moment that section 2 of column can currently withstand; W nx is the net section modulus of column 2, which can be extracted using finite element section analysis software; f is the current effective yield strength of the profile. The steel cost control threshold and unit cost of steel for the project are determined based on the overall budget of this renovation project and the owner's investment limit; the unit cost of steel is obtained by comprehensively calculating the market steel purchase price, processing and manufacturing costs, etc. during the renovation construction period. The maximum allowable assembly space for the spacing between the first through bolt 5 and the third through bolt 7 is determined based on the effective arrangement section length of the column 2. Constrained by the total vertical length of the column 2 itself, the peaked steel sheet 1 needs to reserve sufficient steel sheet clamping section and bolt construction operation allowance on the lower side of the first through bolt 5 and the upper side of the third through bolt 7. After deducting the required reserved dimensions at the upper and lower ends, the maximum allowable assembly space L2 for the spacing between the first through bolt 5 and the third through bolt 7 is obtained.

[0040] In step 101, a first finite element verification model of the peak-shaving device is established based on the measured verification parameters, and the maximum negative bending moment of the support at the middle support position and the bending moment distribution diagram of column 2 without the peak-shaving device under the current service status of the curtain wall are obtained, including: All measured verification parameters, including the cross-sectional dimensions of column 2, the residual mechanical properties of the profile, the curtain wall panel dimensions, the self-weight load, the wind load, and the additional load, were entered into the finite element calculation software to build the first finite element verification model of column 2 without the peak-shaving device. Based on the actual engineering situation, the constraint boundary conditions corresponding to the top support 9, the bottom support 10, and the original middle support of column 2 were defined, and all load combination cases were applied. After the model solution calculation was completed, the software output the bending moment distribution curve of column 2 along the vertical height. The bending moment value corresponding to the middle support position was extracted from it, which is the maximum negative bending moment M1 of the middle support position under the current service status of the curtain wall. At the same time, a complete bending moment distribution diagram of column 2 without the peak-shaving device was obtained. It should be noted that the finite element analysis software selected in this embodiment can be SAP2000, or other similar software with the function of analyzing the stress of bar structures can be selected.

[0041] In step 102, when the maximum negative bending moment at the support position of the curtain wall under its current service status is greater than the ultimate bending moment that the column 2 section can currently withstand, the preliminary values ​​of the spacing between the first through bolt 5 and the third through bolt 7 are obtained according to the bending moment distribution diagram of the column 2 without the peak-cutting device, including: Draw a reference straight line parallel to the axis of column 2 in the bending moment distribution diagram of column 2 without peak cutting device. Translate the reference straight line in the direction of decreasing bending moment value until the bending moment values ​​corresponding to the two intersection points of the reference straight line and the negative bending moment curve of the support are equal to the current ultimate bending moment that the section of column 2 can bear. Take the distance between the two intersection points as the initial value of the spacing between the first through bolt 5 and the third through bolt 7. Please see Figure 6 , Figure 6 This is a bending moment distribution diagram of a column without the support negative bending moment reduction device of this invention, output after calculation by the aforementioned first finite element verification model. When the maximum support negative bending moment M1 at the mid-support position of the curtain wall under its current service condition is greater than the current ultimate bending moment M0 that the column 2 section can withstand, it indicates that the bearing capacity of column 2 is insufficient under the current working conditions, and the support negative bending moment reduction device needs to be added. Figure 6 Draw a reference line parallel to the vertical axis of column 2 in the bending moment distribution diagram shown. Translate the reference line along the direction in which the negative bending moment value decreases. Continuously adjust the position of the reference line until the reference line intersects the negative bending moment curves of the supports on both sides of the middle support at two points, and the bending moment values ​​corresponding to the two intersection points are equal to the current ultimate bending moment M0 that the column 2 section can withstand. Measure the vertical distance between the two intersection points, which is the preliminary value L1 of the spacing between the first through bolt 5 and the third through bolt 7.

[0042] In step 103, based on the preliminary values ​​of the spacing between the first through bolt 5 and the third through bolt 7 and the measured verification base parameters, a second finite element verification model with the peak-shaving device is established to obtain the maximum negative bending moment of the support with the peak-shaving device, including: The measured cross-sectional dimensions of column 2, the residual mechanical properties of the profile, the curtain wall segmentation parameters, the self-weight load, the wind load, the additional load, and the preliminary value L1 of the spacing between the first through bolt 5 and the third through bolt 7, corresponding to the geometric structure information of the peak-shaving device, were entered into the finite element calculation software. Based on the original model of column 2 without the peak-shaving device, components such as the peak-shaving steel sheet 1 and through bolts were added to build a second finite element model with the support negative bending moment peak-shaving device. The constraint boundary conditions and load combination conditions used in the model were consistent with those of the first finite element verification model. After the model solution calculation was completed, the maximum support negative bending moment appearing in the support area of ​​column 2 was extracted and recorded as the maximum support negative bending moment M2 after the peak-shaving device was installed.

[0043] In step 104, based on the maximum negative bending moment of the support equipped with the peak-shaving device and the current ultimate bending moment that the column 2 section can withstand, the minimum value of the spacing between the first through bolt 5 and the third through bolt 7 is obtained, including: The maximum negative bending moment M2 after the peak-shaving device is installed is compared and checked with the current ultimate bending moment M0 that the column 2 section can withstand. If M2 is less than or equal to M0, it means that the length of the peak-shaving device corresponding to the initial value L1 of the spacing between the first through bolt 5 and the third through bolt 7 has met the safety requirements of the bearing capacity of the column 2. At this time, the initial value L1 of the spacing between the first through bolt 5 and the third through bolt 7 is directly used as the minimum value L of the spacing between the first through bolt 5 and the third through bolt 7. min If M2 is still greater than M0, it indicates that the effective working length of the current peak-shaving device is insufficient and the peak-shaving amplitude is limited. It is necessary to gradually increase the spacing between the first through bolt 5 and the third through bolt 7 and remodel and calculate until the maximum negative support bending moment M2 output by the finite element model just meets the safety control condition of M2≤M0. The minimum spacing value that just meets the bearing capacity limit condition of column 2 is determined as the minimum value L for the spacing between the first through bolt 5 and the third through bolt 7. min .

[0044] In step 105, based on the project's steel cost control threshold and the unit cost of steel, the upper limit of the spacing between the first through bolt 5 and the third through bolt 7, which is allowed by the total cost of steel, is obtained, including: Based on the project's steel cost control threshold and unit steel cost, the maximum allowable steel usage for the support negative moment peak reduction device is calculated. Under the premise that the cross-sectional specifications of the support negative moment peak reduction device remain unchanged, the correspondence between the spacing of the first through bolt 5 and the third through bolt 7 and the theoretical steel usage of the support negative moment peak reduction device is established. Based on the maximum steel usage and the correspondence between the spacing of the first through bolt 5 and the third through bolt 7 and the theoretical steel usage of the support negative moment peak reduction device, the upper limit of the spacing between the first through bolt 5 and the third through bolt 7 allowed by the total steel cost is obtained. Specifically, the project's steel cost control threshold is the upper limit of steel-related expenses that can be invested in the peak-shaving device. Dividing the project's steel cost control threshold by the unit cost of steel yields the maximum weight of steel that can be invested in the peak-shaving device. The thickness, width, and other cross-sectional dimensions of the peak-shaving steel sheet 1 are pre-selected and kept constant. Only the vertical distance between the first through bolt 5 and the third through bolt 7 is changed. The total weight of the steel in the peak-shaving device will monotonically increase as the distance increases. Therefore, a positive correlation between the distance length and the weight of the steel can be established. When the weight of the steel reaches the maximum allowable amount, the corresponding distance length is the upper limit L3 of the distance between the first through bolt 5 and the third through bolt 7 allowed by the total cost of steel. If the distance selected subsequently exceeds L3, the material consumption of the peak-shaving device will exceed the budget limit and will not meet the economic requirements of the project.

[0045] In step 106, based on the minimum value of the spacing between the first through bolt 5 and the third through bolt 7, the upper limit of the spacing between the first through bolt 5 and the third through bolt 7 allowed by the total cost of steel, and the maximum allowable assembly space for the spacing between the first through bolt 5 and the third through bolt 7, the effective range of values ​​for the spacing between the first through bolt 5 and the third through bolt 7 is obtained, including: The maximum allowable assembly space L2 for the spacing between the first through bolt 5 and the third through bolt 7 is compared with the upper limit L3 for the spacing obtained from the total steel cost constraint. The smaller of the two values ​​is selected as the maximum value L for the spacing between the first through bolt 5 and the third through bolt 7. max L2 is determined by the vertical length of column 2, the clamping allowance at the end of the steel sheet, and the space for on-site bolt assembly, representing the maximum length that the physical dimensions at the structural level can accommodate; L3 is determined by the budget constraints of the renovation cost, representing the maximum length that can be afforded economically; the design spacing cannot exceed the space constraints, nor can it exceed the cost constraints, therefore it is subject to the control of both conditions simultaneously, and only the smaller value of the two can be taken as the upper limit; combined with the minimum value L of the spacing between the first through bolt 5 and the third through bolt 7 obtained above, min Finally, the effective range of the spacing between the first through bolt 5 and the third through bolt 7 was determined to be: L min ≤L≤L maxThe spacing L between the first through bolt 5 and the third through bolt 7 selected in the subsequent design must fall within this range in order to simultaneously meet the three requirements of column 2's load-bearing safety, on-site assembly feasibility, and controllable project cost.

[0046] It should be noted that after determining the effective range of the spacing between the first through bolt 5 and the third through bolt 7, it is only possible to ensure that the overall length of the peak-shaving device meets the constraints of safety, assembly, and cost. However, the uniformity of the internal force distribution at the upper and lower ends of the single connecting section 4 of the peak-shaving steel sheet 1 cannot be controlled. The vertical installation position of the support adapter 8 on the connecting section 4 directly changes the force distribution ratio of the upper and lower regions of the connecting section 4. If the installation point is not set reasonably, it will cause an excessive difference in the peak bending moment between the upper and lower sections of the connecting section 4, resulting in overload on one side and surplus steel performance on the other side, leading to low overall force utilization efficiency of the peak-shaving device. Therefore, it is necessary to iteratively optimize the distance between the installation point of the connecting section 4 and the support adapter 8 and the third through bolt 7, and find the target distance that controls the difference in bending moment between the upper and lower ends of the connecting section 4 within the allowable deviation, so that the negative bending moment shared by the upper and lower parts of the connecting section 4 of the peak-shaving steel sheet 1 tends to be balanced, giving full play to the material bearing capacity of the entire peak-shaving device and further optimizing the peak-shaving effect.

[0047] Step 107, based on the effective range of the spacing between the first through bolt 5 and the third through bolt 7, determines the reference value of the spacing between the first through bolt 5 and the third through bolt 7, as well as the initial distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing of the third through bolt 7, including: Within the valid range L of the determined spacing between the first through bolt 5 and the third through bolt 7 min ≤L≤L max Within, a suitable value is selected as the reference value L for the distance between the first through bolt 5 and the third through bolt 7. This reference value takes into account both safety margin and economy. Half of the reference value L is used as the initial distance, and the initial distance S1 = L / 2 between the installation point of the connecting section 4 and the support adapter 8 and the distance between the third through bolt 7 is initially set.

[0048] In step 108, based on the reference value of the spacing between the first through bolt 5 and the third through bolt 7, the initial distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing of the third through bolt 7, and the measured verification basic parameters, a third finite element verification model equipped with the peak-shaving device is established to obtain the upper peak bending moment and the lower peak bending moment of the connecting section 4 of the peak-shaving device, including: The measured dimensions of column 2, residual mechanical properties of the profile, curtain wall segmentation parameters, self-weight load, wind load, additional load, the reference value L of the spacing between the first through bolt 5 and the third through bolt 7, and the initial distance S1 between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7 are entered into the finite element calculation software. Based on the aforementioned second finite element verification model, the vertical positioning structure of the connecting section 4 and the support adapter 8 is refined, and the initial distance S1 between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7 is accurately input to build the third finite element verification model with the negative bending moment peak-shaving device. The constraint boundary conditions and load combination conditions used in the model are consistent with the first and second finite element verification models. After completing the model solution calculation, the extreme values ​​of bending moments corresponding to the upper and lower sections of the connecting section 4 of the peak-shaving steel sheet 1 are extracted and recorded as the upper peak bending moment and lower peak bending moment of the connecting section 4 of the peak-shaving device, respectively.

[0049] Step 109, based on the upper and lower peak bending moments of the connecting section 4 of the peak-shaving device, obtains the allowable deviation and the bending moment difference between the upper and lower ends of the connecting section 4 of the peak-shaving device, including: The peak bending moment values ​​at the upper and lower ends of the peak-shaving device connection section 4 output by the third finite element verification model are read, and the absolute difference between the two sets of bending moment values ​​is calculated. This calculation result is defined as the bending moment difference between the upper and lower ends of the peak-shaving device connection section 4. The values ​​of the upper and lower peak bending moments are compared, and the peak bending moment with the larger value is selected as the reference bending moment. The allowable deviation value is preset to 5% of the reference bending moment value. This deviation value is determined by comprehensively referring to the current steel structure reinforcement design code and the conventional stress design range of curtain wall steel connectors.

[0050] In step 110, based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section 4 of the peak-shaving device, the target distance between the installation point of the connecting section 4 and the support adapter 8 and the distance between the third through bolt 7 is obtained, including: When the difference in bending moment between the upper and lower ends of the connecting section 4 of the peak-shaving device is greater than the allowable deviation, the reference value of the spacing between the first through bolt 5 and the third through bolt 7 is kept unchanged. The initial distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7 is adjusted to obtain the adjustment distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7. Based on the reference value of the spacing between the first through bolt 5 and the third through bolt 7, the adjustment distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7, and the measured verification basic parameters, a third finite element verification model equipped with the peak-shaving device is established until the difference in bending moment between the upper and lower ends of the connecting section 4 of the peak-shaving device is less than the allowable deviation. The corresponding adjustment distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7 is taken as the target distance between the installation point of the connecting section 4 and the support adapter 8 and the spacing between the third through bolt 7. Specifically, if the bending moment difference exceeds the allowable deviation, it indicates that the uneven stress distribution on the connecting section 4 of the peak-cutting steel sheet 1 exceeds the acceptable range specified in the standard. Therefore, it is necessary to adjust the vertical installation position of the support adapter 8 and remodel and iterate. The adjustment direction follows the bending moment balance logic, shifting the installation point of the support adapter 8 towards the end with the smaller peak bending moment. This shortens the cantilever length of the connecting section 4 on that side and increases the cantilever length on the other side, thereby reducing the bending moment difference between the two ends. After each installation point shift, the same reference value L is used to compare the adjusted installation points of the connecting section 4 and the support adapter 8. The initial distance between the third through bolt 7 and the third finite element verification model is rebuilt. The original load and boundary constraint conditions are used to carry out the stress calculation and the peak bending moments of the upper and lower parts of the connection segment 4 are extracted again. The above offset, modeling and verification process is repeated until the difference between the upper and lower bending moments of the connection segment 4 of the peak-shaving device is less than or equal to the allowable deviation. After the iteration converges, the adjustment distance between the installation point of the connection segment 4 and the support adapter 8 and the distance between the third through bolt 7 is taken as the target distance S between the installation point of the connection segment 4 and the support adapter 8 and the distance between the third through bolt 7.

[0051] It should be noted that the geometric definition of the target distance S between the installation point of the connecting section 4 and the support adapter 8 and the third through bolt 7 is distinguished between two types of curtain wall scenarios: For the frame curtain wall of Embodiment 1, the support adapter 8 is a supporting steel bracket, and the distance from the installation point of the support adapter 8 to the third through bolt 7 is the vertical distance from the midpoint of the line connecting the axes of the two fourth through bolts 13 along the axis of the column 2 to the third through bolt 7; For the unitized curtain wall of Embodiment 2, the support adapter 8 is a pre-embedded hanging shaft, and the distance from the installation point of the support adapter 8 to the third through bolt 7 is the vertical distance from the center of the force of the slot 15 and the hanging shaft along the axis of the column 2 to the third through bolt 7.

[0052] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A support negative bending moment peak reduction device, characterized in that, include: Two shaving steel plates (1) are respectively disposed on both sides of the column (2); the shaving steel plate (1) includes a fixed section (3) and a connecting section (4); the fixed section (3) is fastened and clamped to both sides of the column (2) by a first through bolt (5), a second through bolt (6) and a third through bolt (7); the axis of the first through bolt (5), the axis of the second through bolt (6) and the axis of the third through bolt (7) are located on the same vertical line parallel to the axis of the column (2); The upper and lower ends of the fixed section (3) gradually narrow towards the middle of the fixed section (3) and protrude from the column (2) to form the connecting section (4), and the connecting section (4) is connected to the support adapter (8) at the main structure of the building. The top of the column (2) is provided with an upper support (9), and the bottom of the column (2) is provided with a lower support (10); the upper support (9) and the lower support (10) are respectively connected to the main structure of the building; the support negative bending moment peak reduction device is provided between the upper support (9) and the lower support (10).

2. The support negative bending moment peak reduction device according to claim 1, characterized in that, Also includes: Two horizontal elongated holes (11) are provided through the surface of the connecting section (4); Two vertical short holes (12) are provided through the end of the support adapter (8). The support adapter (8) is a support steel bracket welded to the embedded plate of the main building structure. The extension direction of the two vertical short holes (12) is perpendicular to the extension direction of the two horizontal long holes (11). The two vertical short holes (12) correspond to and are connected to the two horizontal long holes (11). Two fourth through bolts (13) are inserted, with the threaded ends of the two fourth through bolts (13) passing through two horizontal long holes (11) and two vertical short holes (12) in sequence; the straight line formed by the axes of the two fourth through bolts (13) is parallel to the vertical line.

3. The support negative bending moment peak reduction device according to claim 2, characterized in that, Also includes: Steel washer (14); the steel washer (14) is placed between the connecting section (4) and the bolt head of the fourth through bolt (13), and the surface of the steel washer (14) is provided with a through hole for the fourth through bolt (13) to pass through.

4. The support negative bending moment peak reduction device according to claim 2, characterized in that, The horizontal elongated hole (11) is arranged perpendicular to the axial direction of the column (2). The horizontal elongated hole (11) allows the fourth through bolt (13) to slide along its length to adjust the distance between the supporting steel bracket and the column (2).

5. The support negative bending moment peak reduction device according to claim 2, characterized in that, The vertical short hole (12) is arranged in a direction parallel to the axial direction of the column (2). The supporting steel bracket slides along the axial direction of the column (2) through the vertical short hole (12) relative to the fourth through bolt (13), thereby adjusting the vertical installation elevation of the supporting steel bracket relative to the column (2).

6. The support negative bending moment peak reduction device according to claim 1, characterized in that, The surface of the connecting section (4) is provided with a slot (15), which extends along the axial direction of the column (2); the supporting adapter (8) is a hanging shaft pre-embedded in the main structure of the building, and the slot (15) is engaged with the outside of the hanging shaft.

7. A method for determining parameters of a support negative bending moment peak-shaving device, applied to the support negative bending moment peak-shaving device according to any one of claims 1 to 6, characterized in that, include: Obtain the measured verification foundation parameters of column (2), the ultimate bending moment that the column (2) section can currently withstand, the project steel cost control threshold, the unit cost of steel, and the maximum allowable assembly space for the spacing between the first through bolt (5) and the third through bolt (7); the measured verification foundation parameters include the measured cross-sectional dimensions of column (2), the remaining mechanical properties of column (2) after long-term service, the existing curtain wall grid dimensions, wind load, self-weight load, and the additional load currently actually acting on column (2); Based on the measured verification parameters, a first finite element verification model of the peak-shaving device was established, and the maximum negative bending moment of the support at the middle support position and the bending moment distribution diagram of the column (2) without the peak-shaving device under the current service status of the curtain wall were obtained. When the maximum negative bending moment of the support at the middle support position under the current service status of the curtain wall is greater than the current ultimate bending moment that the column (2) section can bear, the preliminary values ​​of the spacing between the first through bolt (5) and the third through bolt (7) are obtained according to the bending moment distribution diagram of the column (2) without the peak-cutting device. Based on the preliminary values ​​of the spacing between the first through bolt (5) and the third through bolt (7) and the measured verification basic parameters, a second finite element verification model with the peak-shaving device is established to obtain the maximum negative bending moment of the support with the peak-shaving device. Based on the maximum negative bending moment of the support equipped with the peak-shaving device and the current ultimate bending moment that the column (2) section can withstand, the minimum value of the spacing between the first through bolt (5) and the third through bolt (7) is obtained. Based on the project's steel cost control threshold and the unit cost of steel, the upper limit of the spacing between the first through bolt (5) and the third through bolt (7) allowed by the total cost of steel is obtained; Based on the minimum value of the spacing between the first through bolt (5) and the third through bolt (7), the upper limit of the spacing between the first through bolt (5) and the third through bolt (7) allowed by the total cost of steel, and the maximum allowable assembly space for the spacing between the first through bolt (5) and the third through bolt (7), the effective range of values ​​for the spacing between the first through bolt (5) and the third through bolt (7) is obtained. Based on the effective range of the spacing between the first through bolt (5) and the third through bolt (7), determine the reference value of the spacing between the first through bolt (5) and the third through bolt (7), as well as the initial distance between the installation point of the connecting section (4) and the support adapter (8) and the spacing between the third through bolt (7); Based on the reference value of the spacing between the first through bolt (5) and the third through bolt (7), the installation point of the connecting section (4) and the support adapter (8) and the initial distance of the spacing between the third through bolt (7), and the measured verification basic parameters, a third finite element verification model equipped with the peak reduction device is established to obtain the upper peak bending moment and lower peak bending moment of the connecting section (4) of the peak reduction device. Based on the upper peak bending moment and lower peak bending moment of the connecting section (4) of the peak shaving device, the allowable deviation and the bending moment difference between the upper and lower ends of the connecting section (4) of the peak shaving device are obtained. Based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section (4) of the peak-shaving device, the target distance between the installation point of the connecting section (4) and the support adapter (8) and the distance between the third through bolt (7) is obtained.

8. The method for determining the parameters of the support negative bending moment peak reduction device according to claim 7, characterized in that, When the maximum negative bending moment at the support position of the curtain wall under its current service status is greater than the ultimate bending moment that the column (2) section can currently withstand, the preliminary values ​​of the spacing between the first through bolt (5) and the third through bolt (7) are obtained based on the bending moment distribution diagram of the column (2) without the peak-cutting device, including: Draw a reference line parallel to the axis of column (2) in the bending moment distribution diagram of column (2) without peak cutting device. Translate the reference line in the direction of decreasing bending moment value until the bending moment values ​​corresponding to the two intersection points of the reference line and the negative bending moment curve of the support are equal to the current ultimate bending moment that the column (2) section can bear. Take the distance between the two intersection points as the initial value of the spacing between the first through bolt (5) and the third through bolt (7).

9. The method for determining the parameters of the support negative bending moment peak reduction device according to claim 7, characterized in that, Based on the project's steel cost control threshold and the unit cost of steel, the upper limit of the spacing between the first through bolt (5) and the third through bolt (7) allowed by the total cost of steel is obtained, including: The maximum allowable amount of steel for the negative moment peak reduction device of the support is calculated based on the project steel cost control threshold and the unit cost of steel. Under the premise that the cross-sectional specifications of the negative moment peak reduction device of the support remain unchanged, the relationship between the spacing of the first through bolt (5) and the third through bolt (7) and the theoretical amount of steel for the negative moment peak reduction device of the support is established. Based on the maximum amount of steel and the relationship between the spacing of the first through bolt (5) and the third through bolt (7) and the theoretical amount of steel for the negative moment peak reduction device of the support, the upper limit of the spacing between the first through bolt (5) and the third through bolt (7) allowed by the total cost of steel is obtained.

10. The method for determining the parameters of the support negative bending moment peak reduction device according to claim 7, characterized in that, Based on the allowable deviation and the difference in bending moment between the upper and lower ends of the connecting section (4) of the peak-shaving device, the target distance between the installation point of the connecting section (4) and the support adapter (8) and the distance between the third through bolt (7) is obtained, including: When the difference in bending moment between the upper and lower ends of the connecting section (4) of the peak-shaving device is greater than the allowable deviation, the reference value of the spacing between the first through bolt (5) and the third through bolt (7) is kept unchanged. The initial distance between the installation point of the connecting section (4) and the support adapter (8) and the spacing between the third through bolt (7) is adjusted to obtain the adjustment distance between the installation point of the connecting section (4) and the support adapter (8) and the spacing between the third through bolt (7). Based on the reference value of the spacing between the first through bolt (5) and the third through bolt (7), the connecting section (4) The adjustment distance between the installation point of the support adapter (8) and the spacing of the third through bolt (7), and the measured verification basic parameters are used to establish a third finite element verification model equipped with the peak-shaving device, until the difference in bending moment between the upper and lower ends of the connecting section (4) of the peak-shaving device is less than the allowable deviation. The adjustment distance between the installation point of the connecting section (4) and the support adapter (8) and the spacing of the third through bolt (7) is taken as the target distance between the installation point of the connecting section (4) and the support adapter (8) and the spacing of the third through bolt (7).

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