Method for determining pre-buried point and structure of tying device of external scaffold of basement

Abstract

The invention provides a method for determining pre-buried points and a structure of a pulling device of an external scaffold of a basement, and belongs to the technical field of scaffold pre-buried measurement, and the method comprises the following steps: firstly, obtaining structural parameters of an external wall body of the basement, then calculating a design tension value of a single pre-buried point according to the load of the external scaffold, and determining a stress index of a pre-buried multi-section pulling device. Then establishing a pre-buried point vertical spacing calculation model, a pre-buried point horizontal spacing calculation model and a pre-buried point waterproof influence evaluation model based on the wall structure parameters; and carrying out multi-objective optimization calculation on the three models to obtain a pre-buried point arrangement scheme which meets the bearing capacity requirement and has the minimum waterproof damage area. And the space coordinates of the pre-buried points and the component specifications of the pre-buried multi-section type pulling and connecting device are determined according to the pre-buried points. According to the method, the structural characteristics of the basement outer wall body, the stress condition of the outer scaffold and the waterproof construction requirement can be fully considered, and the problems that a waterproof layer is damaged by pre-buried metal accessories, and the waterproof performance is reduced are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of scaffold pre-embedded measurement, and in particular relates to a method for determining pre-embedded points and structures of a basement external scaffold tie-down device. Background Art

[0002] In the process of modern building construction, the construction of the basement exterior wall is a complex and critical link. The basement exterior wall not only bears the load-bearing and waterproof functions, but also needs to provide a stable support point for the external scaffolding during the construction process. At present, the method of pre-embedded anchor points is generally used to fix the external scaffolding in the construction of building projects, which is directly related to the construction safety and project quality. In the prior art, there are mainly the following schemes for the arrangement of the anchor points of the scaffolding on the basement exterior wall: the first is to adopt the equal spacing arrangement method, that is, to determine the vertical and horizontal spacing according to experience, and to arrange the pre-embedded points in a grid shape on the wall. This method is simple to operate, but does not take into account the actual stress conditions, often resulting in excessive support in some areas and insufficient support in other areas. The second is based on the pole position arrangement method, that is, the pre-embedded points are determined according to the spatial position of the scaffolding poles. This method takes into account the structural characteristics of the scaffolding, but ignores the stress characteristics of the basement structure itself. The third is the simplified mechanical calculation method, which uses basic mechanical calculations to determine the position of the key stress points, and then arranges the pre-embedded points, but the calculation process is too simplified and it is difficult to accurately reflect the actual working conditions.

[0003] In terms of construction technology, the traditional method of tying the basement external scaffolding generally uses metal accessories that are fixedly connected to the outer wall, such as bolts, expansion tubes, etc. This method will cause the embedded metal accessories to damage the waterproof layer during waterproof construction, reducing the waterproof performance. Summary of the invention

[0004] In view of this, the present invention provides a method for determining the pre-buried points and structures of a basement external scaffolding tie-down device, which can solve the problem in the prior art that the pre-buried metal accessories may damage the waterproof layer and reduce the waterproof performance during waterproof construction.

[0005] The present invention is achieved in that: The present invention provides a method for determining the pre-buried points and structure of a basement external scaffolding tie-down device, which comprises the following steps: S10, obtaining structural parameters of the basement exterior wall; S20, calculating the design tension value of a single embedded point according to the external scaffolding load, and determining the force index of the embedded multi-stage tie device; S30, establishing a calculation model for the vertical spacing of embedded points based on the wall structure parameters; S40. Establish a calculation model for the horizontal spacing of embedded points based on the lateral stability requirements of the external scaffolding; S50, using the waterproof construction requirements as constraints to establish a pre-buried point waterproof impact assessment model, and calculating the minimum value of the waterproof layer damage area and its corresponding pre-buried point layout plan; S60, performing multi-objective optimization calculation on the vertical spacing calculation model, the horizontal spacing calculation model, and the waterproof impact assessment model to obtain a pre-buried point arrangement plan that meets the bearing capacity requirements and minimizes the waterproof damage area; S70, according to the optimized pre-embedded point arrangement plan, determine the spatial coordinates of each pre-embedded point, and draw a pre-embedded point positioning map; S80, determining the installation position of the embedded multi-stage tie device according to the embedded point positioning diagram, and checking the steel bar avoidance spacing at each embedded point; S90. According to the spatial layout plan of the embedded points, calculate and determine the component specifications of the embedded multi-section anchor device, including the diameter of the bent anchor round steel, the model of the embedded connection cone head, and the length of the external anchor device.

[0006] On the basis of the above technical solution, the method for determining the pre-embedded points and structure of the basement external scaffolding tie-down device of the present invention can also be improved as follows: The structural parameters include wall height, wall thickness, and concrete strength grade.

[0007] Furthermore, the stress indicators at least include tensile strength and stiffness.

[0008] Furthermore, the constraint conditions of the calculation model of the vertical spacing of the embedded points include the tensile strength of the wall, the thickness of the concrete cover, and the distribution position of the steel bars.

[0009] Furthermore, the constraints of the calculation model for the horizontal spacing of the embedded points include the arrangement of scaffolding uprights, the stiffness of the wall connection members, and the wind load.

[0010] Furthermore, the pre-embedded multi-section scaffolding anchoring device includes a pre-embedded force-bearing part, a pre-embedded connecting cone head and an external anchoring device.

[0011] Furthermore, the embedded stress-bearing part is made of bent anchor round steel, and the diameter of the bent anchor round steel is 18 mm to 28 mm; the embedded stress-bearing part is provided with a bent anchor end, a water stop plate and a threaded connection section, the water stop plate is welded to the middle part of the embedded stress-bearing part, the bent anchor end is arranged within the middle part of the wall thickness, and the threaded connection section is located at the end of the embedded stress-bearing part; the embedded connection cone head is an inverted cone, the inner end of the embedded connection cone head is connected to the threaded connection section of the embedded stress-bearing part, and the outer end of the embedded connection cone head is connected to the external tensioning device.

[0012] Furthermore, the length of the external anchoring device is not less than 0.5 meters, and the external anchoring device is rigidly connected to the external scaffolding.

[0013] Furthermore, the embedded connection cone head is made of high-strength plastic; the embedded connection cone head is buried close to the inner side of the concrete, and the external tensioning device and the embedded connection cone head press the template tightly; after the embedded connection cone head and the external tensioning device are installed in place, they provide a tension force not less than the theoretical value of the tension node design.

[0014] Furthermore, the water stop plate is welded to the embedded stress-bearing part by a full welding process; the external tie device adopts a detachable structure, which is removed during the waterproofing construction and restored after the waterproofing construction is completed.

[0015] Furthermore, the calculation model of the design tension value of a single embedded point in S20 is specifically expressed as follows: ; In the formula, Design the tensile force value for the embedded point in kN; is the tensile force component generated by wind load, in kN; is the tensile force component generated by the construction load, in kN; is the tensile force component generated by the deadweight of the scaffold, in kN; is the importance coefficient of each load, and its value range is [0.8,1.2]; is the error correction term, and its value range is [-0.5, 0.5]. Traditional methods usually only consider a single load or simple superposition. This equation introduces the importance coefficient , reflecting the differential contribution of different loads to the tension; the error term The uncertainty in load measurement and calculation is taken into account to improve the adaptability of the model; wind load component The quadratic function relationship is adopted, which is in line with the basic principles of fluid mechanics, and the angle factor is introduced to more accurately describe the directional influence of wind load; the construction load components are in the form of discrete summation, which can flexibly adapt to different construction conditions.

[0016] The calculation methods of various parameters are as follows: ; In the formula, is the wind load coefficient, which is related to the shape of the building and has a value range of [1.2,1.6]; is the design wind speed, in m / s; is the height of the calculation point, in m; It is the angle between wind direction and wall normal, in radians.

[0017] ; In the formula, For the The influence coefficient of construction load; For the Class construction load value, in kN; is the number of construction load types; is the construction load error term.

[0018] Furthermore, the vertical spacing calculation model in S30 is specifically expressed as follows: ; In the formula, is the optimal vertical spacing, in m; is the vertical force correction coefficient, and its value range is [0.8,1.2]; is the design value of concrete tensile strength, in MPa; is the thickness of the protective layer, in mm; is the reinforcement distribution influence coefficient; is the vertical spacing error term. The square root relationship of tensile strength is adopted to reflect the nonlinear relationship between material strength and load; the inverse term of protective layer thickness is introduced , reflects the boundary effect of the protective layer on the anchoring performance; the correction coefficient It can be adjusted according to actual engineering experience, which improves the practicability of the model; compared with traditional empirical formulas, this model takes into account material properties and construction requirements more comprehensively.

[0019] Furthermore, the horizontal spacing calculation model in S40 is specifically expressed as follows: ; In the formula, is the optimal horizontal spacing, in m; is the horizontal force correction factor; is the elastic modulus of the wall connection, in GPa; is the moment of inertia of the wall connection section, in mm^4; is the horizontal spacing error term. A dual restriction mechanism is adopted to control the spacing from two perspectives: component deformation and wind load. The term is based on the deflection control principle and takes into account the quadratic effect of height; The square root relationship of wind speed is introduced into the term, which reflects the restrictive effect of wind load on the spacing; taking the minimum value operation ensures safety.

[0020] Furthermore, the waterproof impact assessment model in S50 is specifically expressed as follows: ; In the formula, is the total area of ​​waterproof layer damage, in m^2; For the Line The influence radius of the embedded point of the column, in m; is the water damage attenuation coefficient; is the spacing between embedded points, in m; The exponential decay model is used to describe the spatial transmission characteristics of the damage effect, which is more in line with the actual engineering phenomenon; the double summation structure takes into account the cumulative impact of all embedded points; the attenuation coefficient is introduced , reflecting the difference in impact of embedded points at different positions; the area calculation adopts the circular impact area assumption to simplify the complex damage form.

[0021] Furthermore, the multi-objective optimization model in S60 is specifically expressed as follows: ; In the formula, To comprehensively optimize the objective function; is the weight coefficient and satisfies ; To allow the maximum damage area; is the maximum allowable tensile force value; For construction costs; The benchmark cost is taken as the benchmark cost. Normalization is adopted to make comprehensive evaluation of indicators of different dimensions. The weight coefficient is adjustable to meet the key requirements of different projects. The three key factors of waterproofing, bearing capacity and economy are taken into consideration.

[0022] Furthermore, the model for determining the spatial coordinates of the embedded points in S70 is specifically expressed as follows: ; ; ; In the formula, Respectively Line The spatial coordinates of the embedded points are in meters. is the elevation of the embedded point, in m; is the total height of the wall, in m; is the total length of the wall, in m; is the reference embedded depth, in m; is the spatial position correction coefficient, and its value range is [-0.1, 0.1]; is the depth-effect attenuation coefficient; is the coordinate error term. The periodic function correction is introduced to consider the influence of wall deformation on the position of the embedded point; the exponential decay term is used to describe the change law in the depth direction; the error terms in three directions are considered separately to improve the positioning accuracy.

[0023] The elevation calculation method is as follows: ; In the formula, is the height adjustment factor; is the reference tension value, in kN; is the elevation error term.

[0024] Furthermore, the component specification determination model in S90 is specifically expressed as follows: Calculation of embedded round steel diameter: ; In the formula, is the diameter of the bent anchor round steel, in mm; is the allowable stress of steel, in MPa; The impact coefficient for long-term use; is the time-dependent attenuation coefficient; is the design service life, in years; is the diameter error term.

[0025] Calculation of embedded cone head size: ; ; In the formula, is the cone head length, in mm; is the maximum diameter of the cone head, in mm; is the cone head size factor; is the position influence coefficient; As the unit reference force, take 1kN; is the size error term.

[0026] Calculation of the length of the external tie device: ; In the formula, is the length of the external tie device, in meters; is the maximum allowable displacement, in m; is the maximum deflection angle, in radians; is the deformation adjustment coefficient; is the elastic modulus of steel, in GPa; is the length error term.

[0027] Compared with the prior art, the method for determining the embedded points and structures of the anchoring device of the basement external scaffolding provided by the present invention has the following beneficial effects: the method can determine the optimal embedded point arrangement scheme by establishing a series of calculation models, including a single embedded point tension calculation model, an embedded point vertical and horizontal spacing optimization model, a waterproof performance impact assessment model, and a multi-objective optimization model. Compared with the traditional method, the main technical advances of the present invention are as follows: 1) By pre-embedding a multi-section anchor device and connecting it to an external anchor piece in a detachable manner, damage to the waterproof layer is greatly reduced, and the quality and reliability of the waterproof construction are improved.

[0028] 2) The optimization algorithm is used to determine the optimal layout of the embedded points, which not only meets the bearing capacity requirements of the structure, but also minimizes the damage area to the waterproof layer and improves the overall construction quality.

[0029] 3) The embedded device adopts bent anchor round steel and embedded connecting cone head and other structural forms, which have sufficient avoidance distance with the steel bars in the wall, avoiding conflicts during the installation process and ensuring structural safety.

[0030] 4) According to the actual layout plan of the embedded points, the size parameters of each component are accurately calculated and determined to ensure the reliability and service life of the overall tensioning device.

[0031] In summary, the present invention solves the problem in the prior art that during waterproof construction, the pre-buried metal accessories may damage the waterproof layer and reduce the waterproof performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flow chart of the method provided by the present invention; Figure 2 This is a schematic diagram of the pre-buried multi-section scaffolding tie-down device; Figure 3 This is a schematic diagram of the relationship between the pre-buried multi-section scaffolding tie-down device and the wall; The reference numerals in the accompanying drawings are explained as follows: 01, bent anchor end, 02, embedded connecting cone head, 03, external tensioning device, 11, bent anchor end, 12, water stop plate, 13, threaded connecting section. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0034] like Figure 1 As shown, it is a flow chart of a method for determining the pre-buried points and structure of a basement external scaffolding tie-down device provided by the present invention. The method comprises the following steps: S10, obtaining structural parameters of the basement exterior wall; S20, calculating the design tension value of a single embedded point according to the external scaffolding load, and determining the force index of the embedded multi-stage tie device; S30, establishing a calculation model for the vertical spacing of embedded points based on the wall structure parameters; S40. Establish a calculation model for the horizontal spacing of embedded points based on the lateral stability requirements of the external scaffolding; S50, using the waterproof construction requirements as constraints to establish a pre-buried point waterproof impact assessment model, and calculating the minimum value of the waterproof layer damage area and its corresponding pre-buried point layout plan; S60, performing multi-objective optimization calculation on the vertical spacing calculation model, the horizontal spacing calculation model, and the waterproof impact assessment model to obtain a pre-buried point arrangement plan that meets the bearing capacity requirements and minimizes the waterproof damage area; S70, according to the optimized pre-embedded point arrangement plan, determine the spatial coordinates of each pre-embedded point, and draw a pre-embedded point positioning map; S80, determining the installation position of the embedded multi-section tie device according to the embedded point positioning diagram, and checking the steel bar avoidance spacing at each embedded point; S90. According to the spatial layout plan of the embedded points, calculate and determine the component specifications of the embedded multi-section anchor device, including the diameter of the bent anchor round steel, the model of the embedded connection cone head, and the length of the external anchor device.

[0035] like Figure 2 As shown, the embedded multi-section scaffolding tie-tying device comprises an embedded stress-bearing part 01, an embedded connecting cone head 02 and an external tie-tying device 03; the embedded stress-bearing part is made of bent anchor round steel, and the diameter of the bent anchor round steel is 18 mm to 28 mm; the embedded stress-bearing part is provided with a bent anchor end 11, a water stop plate 12 and a threaded connection section 13, and the water stop plate 12 is welded to the middle part of the embedded stress-bearing part 01, as shown in FIG. Figure 3 As shown, the bent anchor end 11 is arranged within the middle of the wall thickness, and the threaded connection section 13 is located at the end of the embedded stress-bearing part; the embedded connection cone head 02 is an inverted cone, the inner end of the embedded connection cone head 02 is connected to the threaded connection section 13 of the embedded stress-bearing part 01, and the outer end of the embedded connection cone head 02 is connected to the external tie device 03; the length of the external tie device 03 is not less than 0.5 meters, and the external tie device 03 is rigidly connected to the external scaffolding.

[0036] The embedded connection cone head is made of high-strength plastic; the embedded connection cone head is buried close to the inner side of the concrete, and the external tensioning device and the embedded connection cone head press the template tightly; after the embedded connection cone head and the external tensioning device are installed in place, they provide a tension that is not less than the theoretical value of the tension node design.

[0037] The water stop plate is welded to the embedded stress-bearing part by a full welding process; the external tie device adopts a detachable structure, which is removed during waterproofing construction and restored after the waterproofing construction is completed.

[0038] The specific implementation methods of the above steps are described in detail below: Step S10: Obtaining the structural parameters of the basement exterior wall The purpose of this step is to obtain the basic structural parameters of the current basement exterior wall and provide necessary input conditions for subsequent calculations and optimization. The specific implementation process is as follows: 1) Measure and record the height of the basement exterior wall and thickness .

[0039] 2) Obtain the strength grade of the basement exterior wall concrete by on-site sampling or consulting the design documents .

[0040] 3) Determine the design load of the basement exterior wall, including wind load, based on the specific use of the building , Construction load and self-weight load wait.

[0041] 4) All acquired structural parameters are organized and archived to provide basic data support for subsequent calculations and optimizations.

[0042] Step S20: Determine the design tension value and force index of a single embedded point The purpose of this step is to calculate the design tension value of a single embedded point according to the load of the external scaffolding and determine the force index of the overall tie device. The specific implementation process is as follows: 1) Calculate the design tension value of a single embedded point : ; in, is the importance coefficient of each load, and its value range is ; is the error correction term, and its value range is . , and are the tensile components generated by wind load, construction load and self-weight load respectively, and the calculation formula is as follows: ; ; In the formula, is the wind load factor, is the design wind speed, To calculate the point height, is the angle between wind direction and wall normal; For the The influence coefficient of construction load, For the Class construction load value, is the number of construction load types, is the construction load error term.

[0043] 2) According to the design tension value of a single embedded point , determine the stress indicators of the overall tensioning device, including tensile strength, stiffness, etc.

[0044] Step S30: Determine the vertical spacing of the embedded points The purpose of this step is to establish a calculation model for the vertical spacing of pre-embedded points based on the structural parameters of the basement's outer wall to meet the tensile strength requirements of the wall. The specific implementation process is as follows: 1) Calculate the optimal vertical spacing of embedded points : ; in, is the vertical force correction coefficient, and its value range is ; is the design value of concrete tensile strength; is the thickness of the protective layer; is the reinforcement distribution influence coefficient; is the vertical spacing error term.

[0045] 2) The calculated optimal vertical spacing As a constraint condition, ensure that the layout of the embedded points meets the tensile bearing capacity requirements of the basement exterior wall.

[0046] Step S40: Determine the horizontal spacing of the embedded points The purpose of this step is to establish a calculation model for the horizontal spacing of embedded points based on the lateral stability requirements of the external scaffolding to ensure the stability of the overall structure. The specific implementation process is as follows: 1) Calculate the optimal horizontal spacing of embedded points : ; in, is the horizontal force correction factor; is the elastic modulus of the wall connection; is the section moment of inertia of the wall connection; is the horizontal spacing error term.

[0047] 2) The calculated optimal horizontal spacing As a constraint, ensure that the embedded point layout meets the lateral stability requirements of the external scaffolding.

[0048] Step S50: Evaluate the impact of pre-buried point arrangement on waterproof performance The purpose of this step is to establish an evaluation model for the impact of pre-buried point layout on waterproof layer damage to ensure the quality and reliability of waterproof construction. The specific implementation process is as follows: 1) Calculate the total damaged area of ​​the waterproof layer under the pre-buried point layout scheme : ; in, For the Line The influence radius of the column embedded point; is the attenuation coefficient for water damage; is the spacing of embedded points; Calculate the error term for the area.

[0049] 2) The calculated damaged area of ​​the waterproof layer As part of the optimization objective function, the negative impact of the embedded point layout on the waterproof performance is minimized.

[0050] Step S60: Multi-objective optimization calculation of pre-embedded point layout plan The purpose of this step is to comprehensively consider the bearing capacity requirements and waterproof performance, and obtain the optimal pre-embedded point layout plan through multi-objective optimization calculation. The specific implementation process is as follows: 1) Construct a multi-objective optimization model: ; in, is the weight coefficient, satisfying ; is the maximum allowable damage area; is the maximum allowable tensile force; For construction costs; is the base cost.

[0051] 2) Through multi-objective optimization algorithms, such as the Pareto optimization algorithm, the optimal pre-buried point layout plan that meets the bearing capacity and waterproof performance requirements is solved.

[0052] Step S70: Determine the spatial coordinates of the embedded point The purpose of this step is to calculate and determine the spatial coordinate position of each embedded point based on the optimized embedded point layout plan, so as to provide a basis for the subsequent embedded device installation. The specific implementation process is as follows: 1) Calculate the plane coordinates of the embedded points and : ; ; in, is the elevation of the embedded point, which can be calculated according to the following formula: ; 2) Calculate the vertical coordinates of the embedded point: ; 3) Arrange the calculated spatial coordinates of all embedded points into an embedded point positioning map to provide a basis for subsequent embedded device installation.

[0053] Step S80: Determine the installation position of the embedded device and the steel bar avoidance The purpose of this step is to determine the specific installation position of the embedded multi-section tie device according to the optimized embedded point layout plan, and check whether it interferes with the steel bars in the wall. The specific implementation process is as follows: 1) According to the embedded point positioning diagram, install the embedded multi-section tie device at each embedded point.

[0054] 2) Check the distribution of steel bars at each embedded point to ensure that there is enough clearance between the embedded device and the steel bars to avoid interference.

[0055] 3) For embedded points that cannot meet the steel bar avoidance requirements, it is necessary to adjust the installation position of the embedded device to ensure structural safety.

[0056] Step S90: Determine the component specifications of the embedded device The purpose of this step is to calculate and determine the specific size parameters of each component of the pre-embedded multi-stage tie device based on the optimized pre-embedded point layout plan. The specific implementation process is as follows: 1) Calculate the diameter of the embedded round steel : ; in, is the allowable stress of steel, is the long-term use impact coefficient, is the time-dependent attenuation coefficient, Design service life, is the diameter error term.

[0057] 2) Calculate the size of the embedded cone head and : ; ; in, is the cone head size factor, is the position influence coefficient, is the unit reference force, is the size error term.

[0058] 3) Calculate the length of the external tie device : ; in, is the maximum allowable displacement, is the maximum deflection angle, is the deformation adjustment coefficient, is the elastic modulus of steel, is the length error term.

[0059] 4) Organize and archive the calculated component parameters to provide a basis for the subsequent manufacturing and installation of embedded devices.

[0060] Specifically, the principle of the present invention is: the design and arrangement method of the pre-buried points of the basement external scaffolding anchoring device proposed in the present invention is based on a comprehensive analysis of the structural characteristics of the basement external wall, the load characteristics of the external scaffolding and the waterproof construction requirements, and is obtained by establishing a series of mathematical models for optimization calculation.

[0061] First, in step S10, the structural parameters of the basement outer wall are obtained, including the wall height, thickness and concrete strength grade. These parameters are not only the basic input for subsequent calculation and optimization, but also the prerequisite for ensuring structural safety.

[0062] Secondly, in step S20, a design tension value calculation model for a single embedded point is established based on the load acting on the external scaffolding. The model takes into account factors such as wind load, construction load and self-weight load, and introduces importance coefficients and error correction items, which can more accurately predict the tension that a single embedded point needs to bear. At the same time, the force index of the overall tie device is also determined to provide a basis for subsequent structural design.

[0063] In steps S30 and S40, optimization calculation models for the vertical spacing and horizontal spacing of the embedded points are established respectively. The former is aimed at meeting the tensile bearing capacity of the wall, while the latter is aimed at ensuring the lateral stability of the external scaffolding. By solving these two models, the optimal embedded point arrangement scheme that meets the structural safety requirements can be obtained.

[0064] Step S50 focuses on the quality of waterproof construction and establishes an evaluation model for the impact of embedded point layout on waterproof layer damage. The model takes into account the geometric position of the embedded points and their interactions, and can predict the total damaged area of ​​the waterproof layer. Taking this indicator as part of the optimization objective function can ensure that the embedded point layout plan minimizes the damage to the waterproof layer while meeting the bearing capacity requirements.

[0065] Finally, in step S60, the above models are combined to perform multi-objective optimization calculations to obtain the optimal pre-embedded point layout plan that takes into account both structural safety and waterproof performance. This provides a basis for the subsequent installation of the pre-embedded device and its size determination.

[0066] Through the above series of calculation models and optimization steps, the method of the present invention can fully consider the structural characteristics of the basement outer wall, the stress conditions of the external scaffolding and the requirements of waterproof construction, and finally determine a pre-embedded point arrangement scheme that can not only meet the structural safety but also minimize the impact on the waterproof layer. This not only improves the construction quality, but also greatly improves the convenience and efficiency of construction.

[0067] In order to better understand and implement the present invention, a specific embodiment of the present invention is provided below: the length of the outer wall of a basement is 45 meters, the height is 12 meters, and the concrete strength grade is C30. According to the architectural design, the expected load of the external scaffolding is as follows: the design wind speed is 32m / s, the average wind pressure at the height of the wall is 0.8kPa; the total of various construction loads is 32kN; the deadweight of the scaffolding is 18kN.

[0068] First, according to step S10, the structural parameters of the basement outer wall are obtained: Wall height ; Wall thickness

[0069] Concrete strength grade ; Design wind speed ; Wind load ; Construction load

[0070] Self-weight load ; Next, according to step S20, the design tension value and force index of a single embedded point are determined.

[0071] Calculate the design tension value of a single embedded point : ; in, .

[0072] Substitute the parameters and calculate: ; ; ; ; According to the design tension value of a single embedded point , determine the stress indicators of the overall tensioning device, such as tensile strength not less than 60kN, stiffness not less than 3000kN / m, etc.

[0073] Then, according to step S30, the vertical spacing of the embedded points is determined.

[0074] Calculate the optimal vertical spacing of embedded points : ; in, .

[0075] Substitute the parameters and calculate: ; According to step S40, the horizontal spacing of the embedded points is determined.

[0076] Calculate the optimal horizontal spacing of embedded points : ; in, .

[0077] Substitute the parameters and calculate: ; Next, according to step S50, the influence of the pre-buried point arrangement on the waterproof performance is evaluated.

[0078] Calculate the total damaged area of ​​the waterproof layer under the pre-buried point layout scheme : ; in, .

[0079] Substitute the parameters and calculate: ; Then, according to step S60, a multi-objective optimization calculation is performed to calculate the pre-buried point arrangement plan.

[0080] Constructing a multi-objective optimization model: ; in, .

[0081] Substitute the parameters and calculate: ; The optimal pre-embedded point arrangement scheme is obtained by solving the Pareto optimization algorithm as follows: Vertical spacing of embedded points ; Horizontal spacing of embedded points

[0082] Waterproof layer damage area ; Comprehensive optimization goals ; Next, according to step S70, the spatial coordinates of the embedded point are determined.

[0083] Calculate the plane coordinates of the embedded point and : ; ; in, .

[0084] Calculate the elevation of the embedded point : ; in, .

[0085] Substitute the parameters and calculate: ; Calculate the vertical coordinates of the embedded point: ; in, .

[0086] Substitute the parameters and calculate: ; Through the above calculation, the three-dimensional spatial coordinates of each embedded point are obtained, as shown in Table 1: Table 1 Pre-embedded point spatial coordinate table

[0087] Finally, according to steps S80 and S90, the installation position and component specifications of the embedded device are determined.

[0088] The embedded device consists of three parts: the embedded force-bearing part, the embedded connection cone head and the external tie device. Among them, the embedded force-bearing part is made of 22mm diameter bent anchor round steel, equipped with a bent anchor end, a water stop plate and a threaded connection section. The embedded connection cone head is an inverted cone made of high-strength plastic, the inner end is connected to the threaded connection section of the embedded force-bearing part, and the outer end is connected to the external tie device. The external tie device is 1.2 meters long, adopts a detachable structure, and is rigidly connected to the external scaffolding.

[0089] During installation, first arrange the position of each embedded point according to the spatial coordinates of the embedded points in Table 1, and check whether there is interference with the steel bars in the wall. After inspection, the position of each embedded point meets the steel bar avoidance requirements. Then, install the embedded force-bearing part at each embedded point and connect it to the external tie device through the embedded connection cone head. During waterproofing construction, the external tie device can be disassembled and restored after the waterproofing is completed.

[0090] According to the design tension value of a single embedded point , calculate and determine the specific size parameters of each embedded device component: Embedded round steel diameter ; Embedded cone length ; Maximum diameter of embedded cone ; External tie device length .

[0091] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for determining the embedded points and structure of a basement external scaffolding tie-down device, characterized in that: The following steps are involved: S10, obtaining structural parameters of the basement exterior wall; S20, calculating the design tension value of a single embedded point according to the external scaffolding load, and determining the force index of the embedded multi-stage tie device; S30, establishing a calculation model for the vertical spacing of embedded points based on the wall structure parameters; S40. Establish a calculation model for the horizontal spacing of embedded points based on the lateral stability requirements of the external scaffolding; S50, using the waterproof construction requirements as constraints to establish a pre-buried point waterproof impact assessment model, and calculating the minimum value of the waterproof layer damage area and its corresponding pre-buried point layout plan; S60, performing multi-objective optimization calculation on the vertical spacing calculation model, the horizontal spacing calculation model, and the waterproof impact assessment model to obtain a pre-buried point arrangement plan that meets the bearing capacity requirements and minimizes the waterproof damage area; S70, according to the optimized pre-embedded point arrangement plan, determine the spatial coordinates of each pre-embedded point, and draw a pre-embedded point positioning map; S80, determining the installation position of the embedded multi-stage tie device according to the embedded point positioning diagram, and checking the steel bar avoidance spacing at each embedded point; S90. According to the spatial layout plan of the embedded points, calculate and determine the component specifications of the embedded multi-section anchor device, including the diameter of the bent anchor round steel, the model of the embedded connection cone head, and the length of the external anchor device.

2. A method for determining the pre-buried points and structure of a basement external scaffolding tie-down device according to claim 1, characterized in that: The structural parameters include wall height, wall thickness, and concrete strength grade.

3. A method for determining the pre-buried points and structure of a basement external scaffolding tie-down device according to claim 2, characterized in that: The stress indicators at least include tensile strength and stiffness.

4. A method for determining the pre-buried points and structure of a basement external scaffolding tie-down device according to claim 3, characterized in that: The constraint conditions of the calculation model for the vertical spacing of the embedded points include the tensile strength of the wall, the thickness of the concrete cover, and the distribution position of the steel bars.

5. A method for determining the pre-buried points and structure of a basement external scaffolding tie-down device according to claim 4, characterized in that: The constraint conditions of the calculation model for the horizontal spacing of the embedded points include the arrangement of scaffolding uprights, the stiffness of the wall connection members, and the wind load.

6. A method for determining the pre-buried points and structure of a basement external scaffolding anchoring device according to claim 5, characterized in that: The pre-embedded multi-section scaffolding tie-tying device comprises a pre-embedded force-bearing part, a pre-embedded connecting cone head and an external tie-tying device.

7. A method for determining the pre-buried points and structure of the basement external scaffolding anchoring device according to claim 6, characterized in that: The embedded stress-bearing part is made of bent anchor round steel, and the diameter of the bent anchor round steel is 18 mm to 28 mm; the embedded stress-bearing part is provided with a bent anchor end, a water stop plate and a threaded connection section, the water stop plate is welded to the middle part of the embedded stress-bearing part, the bent anchor end is arranged within the middle part of the wall thickness, and the threaded connection section is located at the end of the embedded stress-bearing part; the embedded connection cone head is an inverted cone, the inner end of the embedded connection cone head is connected to the threaded connection section of the embedded stress-bearing part, and the outer end of the embedded connection cone head is connected to the external tensioning device.

8. A method for determining the pre-buried points and structure of the basement external scaffolding anchoring device according to claim 7, characterized in that: The length of the external tie-down device is not less than 0.5 meters, and the external tie-down device is rigidly connected to the external scaffolding.

9. A method for determining the pre-buried points and structure of a basement external scaffolding anchoring device according to claim 8, characterized in that: The embedded connection cone head is made of high-strength plastic; the embedded connection cone head is buried close to the inner side of the concrete, and the external tensioning device and the embedded connection cone head press the template tightly; after the embedded connection cone head and the external tensioning device are installed in place, they provide a tension that is not less than the theoretical value of the tension node design.

10. A method for determining the pre-buried points and structure of the basement external scaffolding anchoring device according to claim 9, characterized in that: The water stop plate is welded to the embedded stress-bearing part by a full welding process; the external tie device adopts a detachable structure, which is removed during waterproofing construction and restored after the waterproofing construction is completed.

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