A fire protection design method for stainless steel core beam structure

Abstract

The present invention provides a fire protection design method for a stainless steel core plate beam structure, establishes a relationship between the load ratio of the stainless steel core plate beam and the critical temperature of the lower flange, and a relationship between the fire protection equivalent thermal resistance and the lower flange temperature under different fire exposure times, and then establishes an empirical formula for the fire protection equivalent thermal resistance required to achieve a specified fire resistance limit under different load ratios. This solves the problem that existing design methods cannot be fully applied to the fire protection design of stainless steel core plate beam structures, simplifies the fire resistance design process of stainless steel core plate beams, improves the usability and scalability of stainless steel core plate components, and provides a reference for the fire resistance design of stainless steel core plate structure construction projects.

Description

Technical Field

[0001] The present invention relates to the field of steel structure fire protection, and in particular to a fire protection design method for a stainless steel core plate beam structure. Background Art

[0002] The stainless steel core panel structural system building is a new type of lightweight prefabricated structural building. Its core components, such as beams, columns, floor slabs, and walls, are all made of stainless steel core panels. The stainless steel core panel consists of two stainless steel plates sandwiching an array of extremely thin circular core tubes, which are connected together by 1100°C hot air copper brazing. The space between the core tubes can be filled with thermal and sound insulation materials, and stainless steel plates can be welded around the edges to seal. The stainless steel core panel combines the material advantages of stainless steel with the structural advantages of honeycomb sandwich panels: lightweight and high strength, corrosion resistance, flat and beautiful appearance, factory prefabrication, and rapid construction. At the same time, thanks to the core technology of hot air copper brazing, the cost of the core panel structure is controllable, thus having broad development prospects and market promotion value.

[0003] Steel structures are not fire-resistant, and the widespread application of stainless steel core panel structures urgently requires addressing their fire resistance. The "Code for Fire Protection Design of Buildings" (GB 50016-2014) classifies civil building fire resistance levels into levels one, two, three, and four, and sets specific requirements for the combustion performance and fire resistance limits of components in buildings with different fire resistance levels. Currently, scholars have conducted some experimental and theoretical research on the high-temperature mechanical properties of stainless steel core panel materials. However, there are no reports on the fire resistance of stainless steel core panel components, and research on fire-resistant design methods for stainless steel core panel components is largely unresolved.

[0004] The stainless steel core plate beam is one of the main components of the stainless steel core plate structure building. In a fire accident, it is often in a state of being exposed to fire on three sides, so it is usually necessary to carry out fire protection on the three fire-exposed surfaces of the stainless steel core plate beam. Through research, the inventors found that due to the cross-sectional form of the alternating arrangement of the core tube and the sound insulation and heat insulation materials inside the stainless steel core plate beam, the temperature field distribution of the stainless steel core plate beam structure under fire is uneven, which is different from conventional cross-section beams such as H-shaped and rectangular. The fire protection design of building steel structures in the "Technical Code for Fire Protection of Building Steel Structures" GB51249-2017 is basically based on the premise of uniform distribution of the fire temperature field, and the key parameters of the calculation formula are derived and determined. Therefore, the existing fire resistance design of building steel structures cannot be fully applied to stainless steel core plate beam structures. In addition, the existing technology mainly obtains key parameters of structural fire resistance design such as the thickness of the fire protection layer through experimental means, and the acquisition method is relatively cumbersome and complicated. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a fire protection design method for a stainless steel core plate beam structure, filling the gap in the fire resistance design method of stainless steel core plate components, solving the problem that the existing design method cannot be fully applied to the fire protection design of stainless steel core plate beam structures, simplifying the fire resistance design process of stainless steel core plate beams, improving the usability and scalability of stainless steel core plate components, and providing a reference for the fire resistance design of stainless steel core plate structure construction projects.

[0006] According to a first aspect of the present invention, a fire protection design method for a stainless steel core beam structure is provided, which is characterized by comprising:

[0007] Step 20: Determine the load ratio η and the critical temperature T of the lower flange when the stainless steel core beam reaches the fire failure state u According to the fire response data of the lower flange when the stainless steel core plate beam structure fails under different load ratios η, T is fitted. u The relationship between η and the parameter value is determined to obtain formula 1:

[0008] T u =-1978.6η 2 +1021.6η+737.83 (1)

[0009] Step 30: Determine the fire protection equivalent thermal resistance R i The temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time v According to the relationship between different fire exposure time and different fire protection equivalent thermal resistance R i The fire response data of the lower flange of the stainless steel core beam under the action of T v With R i The relationship between them is used to determine the parameter values ​​and obtain Formula 2:

[0010] R i =αln(T v )+β (2)

[0011] Among them, the values ​​of parameters α and β are different under different fire exposure times.

[0012] Step 40: Determine the load ratio η and the fire protection equivalent thermal resistance R i relationship; when T v Reach T u According to Formula 1 and Formula 2, the empirical formula for the fire protection equivalent thermal resistance required for the stainless steel core plate beam to reach the fire resistance limit under specific load ratio conditions is obtained:

[0013] R i =αln(-1978.6η 2 +1021.6η+737.83)+β (3)

[0014] Step 50: Calculate the thickness d of the fire protection layer of the stainless steel core beam that meets the fire resistance grade requirements of the building project i .

[0015] According to the fire resistance grade requirements of the construction project, the fire resistance limit of the stainless steel core plate beam structure is determined; according to the fire resistance limit of the stainless steel core plate beam structure, the values ​​of the parameters α and β are determined; according to the specifications of the stainless steel core plate beams used in the construction project and the initial load design values ​​of the construction project components, the value of the load ratio η that meets the needs of the construction project is determined.

[0016] According to formula 3, the equivalent thermal resistance R of the stainless steel core beam fire protection that meets the fire resistance grade requirements of the construction project is calculated. i The value of .

[0017] Determine the equivalent heat transfer coefficient λ of the fire protection material according to the specifications of the fire protection material used in the construction project i The value of fire protection layer thickness d of stainless steel core beam that meets the fire resistance grade requirements of construction engineering is calculated. i =R i ·λ i .

[0018] Furthermore, the present invention is characterized in that, before step 20, it also includes: step 10: obtaining fire response data of the stainless steel core plate beam through finite element simulation.

[0019] The finite element software ABAQUS is used to establish a stainless steel core beam model. The stainless steel core beam includes: upper flange, web, core tube, thermal and sound insulation material, fire protection layer, and lower flange. Each component is connected into a whole using Tie constraints.

[0020] Set the model's thermal parameters, boundary conditions, mesh size, and element type. Based on historical construction project data, set multiple sets of operating conditions, including fire exposure time, load ratio, and fire protection equivalent thermal resistance. The load ratio is the ratio of the load on the stainless steel core plate beam during fire to the ultimate load of the stainless steel core plate beam at room temperature.

[0021] Finite element simulation was performed using the thermal-mechanical sequential coupling analysis method to obtain the fire response data of the stainless steel core plate beam under different working conditions, including: the critical temperature of the lower flange of the stainless steel core plate beam when it reaches the fire failure state, and the temperature of the lower flange of the stainless steel core plate beam after a certain fire exposure time.

[0022] Furthermore, the present invention provides a method characterized in that step 30 further comprises: determining the fire protection equivalent heat R i The temperature T of the lower flange of the stainless steel core beam after 1 hour, 1.5 hours and 2 hours of fire vIn formula 2, 1 hour of fire corresponds to α = -0.316, β = 2.1554, 1.5 hours of fire corresponds to α = -0.43, β = 2.981, and 2 hours of fire corresponds to α = -0.524, β = 3.6608.

[0023] Step 50 also includes: determining the fire exposure time according to the fire resistance limit of the stainless steel core beam structure, and selecting the corresponding values ​​of parameters α and β.

[0024] Furthermore, the present invention is characterized in that step 50 further comprises: obtaining the ultimate load value q of the stainless steel core plate beam at room temperature according to the historical data corresponding to the specifications of the stainless steel core plate beam used in the construction project room , according to the initial load design value of the construction engineering beam component, determine the load design value q of the stainless steel core plate beam when it is exposed to fire fire , calculate the load ratio that meets the needs of the construction project

[0025] Furthermore, the present invention is characterized in that the thermal sequential coupling analysis method in step 10 includes:

[0026] Step a: Select the fire-exposed surfaces on the webs and lower flanges on both sides, and select the corresponding fire temperature rise curve according to different building project types to heat the fire-exposed surfaces. Simulate the change of the internal temperature of the stainless steel core plate beam with time under the action of fire on three sides, and solve the structural temperature field.

[0027] Step b: Apply the obtained temperature field to the stainless steel core plate beam subjected to a certain external load, and analyze the mechanical response of the stainless steel core plate beam under the action of constant load and temperature increase, including: the change in the mid-span deflection of the stainless steel core plate beam with the increase of time or temperature.

[0028] Step c: Record the temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time. v The fire exposure time includes 1 hour, 1.5 hours, and 2 hours; record the critical temperature T of the lower flange when the stainless steel core plate beam reaches the fire failure state u The fire failure state is determined by the mid-span bending deformation and the mid-span bending deformation rate of the stainless steel core plate beam. When the mid-span bending deformation exceeds the limit complete deformation When the stainless steel core plate beam reaches the fire failure state; when the mid-span bending deformation exceeds 1 / 30 of the clear span length, when the mid-span bending deformation rate exceeds the limit bending deformation rate When the fire is too severe, the stainless steel core beam also reaches the state of failure due to fire.

[0029] According to a second aspect of the present invention, a computer device is provided, characterized in that it includes: a memory for storing instructions; and a processor for calling the instructions stored in the memory to execute the fire protection design method for stainless steel core plate beam structure of the first aspect.

[0030] According to a third aspect of the present invention, a computer-readable storage medium is provided, characterized in that instructions are stored therein, and when the instructions are executed by a processor, the fire protection design method for a stainless steel core plate beam structure of the first aspect is executed.

[0031] Compared with the existing technology, the present invention addresses the problems of uneven fire temperature field in the stainless steel core plate beam structure and unapplicability of common fire-resistant design methods for building steel structures. It establishes the relationship between the load ratio of the stainless steel core plate beam and the critical temperature of the lower flange, and the relationship between the equivalent thermal resistance of fire protection and the temperature of the lower flange under different fire exposure times. Furthermore, it establishes an empirical formula for the equivalent thermal resistance of fire protection required to achieve the specified fire resistance limit under different load ratios, and proposes a fire protection design method suitable for stainless steel core plate beam structures. This fills the gap in the fire-resistant design method of stainless steel core plate components, improves the usability and promotion of the stainless steel core plate structure, and provides a reference for the fire-resistant design of stainless steel core plate structure construction projects.

[0032] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0034] Figure 1 The figure is a schematic diagram of a fire protection design process for a stainless steel core beam structure according to an exemplary embodiment.

[0035] Figure 2 Schematic diagram of a stainless steel core beam structure according to an exemplary embodiment. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0037] The stainless steel core plate beam structure involved in the present invention includes an upper flange, a web, a core tube, a heat and sound insulation material, a fire protection layer, and a lower flange. Figure 2As shown, the fire protection of the stainless steel core plate beam includes adding fireproof materials to the outside of the three fire-exposed surfaces (lower flange and two side webs) of the stainless steel core plate beam structure to form a fireproof protection layer.

[0038] The embodiment of the present invention provides a fire protection design method for a stainless steel core beam structure, such as Figure 1 As shown, it includes steps 20 to 50:

[0039] Step 20: Determine the load ratio η and the critical temperature T of the lower flange when the stainless steel core beam reaches the fire failure state u According to the fire response data of the lower flange when the stainless steel core plate beam structure fails under different load ratios η, T is fitted. u The relationship between η and the parameter value is determined to obtain formula 1:

[0040] T u =-1978.6η 2 +1021.6η+737.83 (1)

[0041] Usually, the relationship between the critical temperature and the corresponding load ratio is combined through the drawing software origin, and the linear fitting type is selected according to the curve trend. The fitting obtains Formula 1 and determines the key parameter value.

[0042] Step 30: Determine the fire protection equivalent thermal resistance R i The temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time v According to the relationship between different fire exposure time and different fire protection equivalent thermal resistance R i The fire response data of the lower flange of the stainless steel core beam under the action of T v With R i The relationship between them is used to determine the parameter values ​​and obtain Formula 2:

[0043] R i =αln(T v )+β (2)

[0044] Among them, the values ​​of parameters α and β are different under different fire exposure times.

[0045] Usually, the relationship between the lower flange temperature and the corresponding equivalent thermal resistance under different fire exposure times is combined through the drawing software origin. The linear fitting type is selected according to the curve trend, and the fitting is used to obtain Formula 2. The values ​​of the key parameters α and β of Formula 2 under different fire exposure times are determined.

[0046] Step 40: Determine the load ratio η and the fire protection equivalent thermal resistance R i relationship; when T v Reach T uWhen the fire protection equivalent thermal resistance required for the stainless steel core beam to reach the fire resistance limit under specific load ratio conditions is obtained according to Formula 1 and Formula 2, that is, Formula 3:

[0047] R i =αln(-1978.6η 2 +1021.6η+737.83)+β (3)

[0048] Step 50: Calculate the thickness d of the fire protection layer of the stainless steel core beam that meets the fire resistance grade requirements of the building project i .

[0049] According to the fire resistance grade requirements of the construction project, the fire resistance limit of the stainless steel core plate beam structure is determined; according to the fire resistance limit of the stainless steel core plate beam structure, the values ​​of the parameters α and β are determined; according to the specifications of the stainless steel core plate beams used in the construction project and the initial load design values ​​of the construction project components, the value of the load ratio η that meets the needs of the construction project is determined.

[0050] According to formula 3, the equivalent thermal resistance R of the stainless steel core beam fire protection that meets the fire resistance grade requirements of the construction project is calculated. i The value of .

[0051] Determine the equivalent heat transfer coefficient λ of the fire protection material according to the specifications of the fire protection material used in the construction project i The value of fire protection layer thickness d of stainless steel core beam that meets the fire resistance grade requirements of construction engineering is calculated. i =R i ·λ i .

[0052] In some embodiments, before step 20 , the method further includes: step 10 : obtaining fire response data of the stainless steel core beam through finite element simulation.

[0053] Finite element software ABAQUS is used to establish a stainless steel core beam model. The stainless steel core beam includes: upper flange, web, core tube, thermal and sound insulation material, fire protection layer, lower flange, and each component is connected into a whole using Tie constraints. Figure 2 shown.

[0054] The model's thermal parameters, boundary conditions, mesh size, and unit type can be set based on previous research and recommended values ​​from standards and specifications. Multiple sets of operating conditions can be set based on historical construction project data, including load ratios and fire protection equivalent thermal resistances. The load ratio is the ratio of the load on the stainless steel core beam when exposed to fire to the ultimate load of the stainless steel core beam at room temperature.

[0055] Finite element simulation was performed using a sequential thermal-mechanical coupling analysis method. This involved first performing a heat transfer analysis to determine the temperature field of the beam structure (i.e., the temperature-time variation trend). The resulting temperature field was then applied to a core beam subjected to a certain external load to analyze the mechanical response of the stainless steel core beam under constant load and temperature increase (i.e., the change in mid-span deflection of the beam with increasing time and temperature).

[0056] The fire response data of the stainless steel core plate beam under different working conditions are obtained, including: the critical temperature of the lower flange of the stainless steel core plate beam when it reaches the fire failure state, and the temperature of the lower flange of the stainless steel core plate beam after a certain fire exposure time.

[0057] In some embodiments, step 30 further includes: determining the fire protection equivalent heat R i The temperature T of the lower flange of the stainless steel core beam after being exposed to fire for 1.0 hour, 1.5 hours and 2.0 hours v In formula 2, 1.0 hours of fire corresponds to α = -0.316, β = 2.1554, 1.5 hours of fire corresponds to α = -0.43, β = 2.981, and 2.0 hours of fire corresponds to α = -0.524, β = 3.6608. As shown in the following table:

[0058]

[0059] Step 50 also includes: determining the fire exposure time according to the fire resistance limit of the stainless steel core beam structure, and selecting the corresponding values ​​of parameters α and β.

[0060] Typically, a relationship is established between the temperature of the lower flange of a stainless steel core beam and the equivalent thermal resistance for fire protection after exposure to fire for 1.0, 1.5, and 2.0 hours (see Formula 2). Based on the design temperature of the lower flange of the stainless steel core beam at a specific exposure time, the design equivalent thermal resistance for fire protection required to achieve the design temperature for the lower flange of the stainless steel core beam at that exposure time can be calculated.

[0061] In some embodiments, step 50 further includes: obtaining the ultimate load value q of the stainless steel core plate beam at room temperature according to the historical data corresponding to the specifications of the stainless steel core plate beam used in the construction project. room , according to the initial load design value of the construction engineering beam component, determine the load design value q of the stainless steel core plate beam when it is exposed to fire fire , calculate the load ratio that meets the needs of the construction project

[0062] Specifically, the proposed stainless steel core plate specifications (dimensions of each structural component) are determined; the manufacturer, based on historical data corresponding to the proposed stainless steel core plate specifications, provides the theoretical value of the ultimate load of the stainless steel core plate beam structure at room temperature. The design value of the load to which the stainless steel core plate beam structure will be subjected in the event of a fire is determined based on the design value of the initial load of the construction engineering beam component; the load ratio of the stainless steel core plate beam in the event of a fire is calculated by dividing the design value of the load effect to which the stainless steel core plate beam structure will be subjected in the event of a fire with the theoretical value of the ultimate bearing capacity at room temperature.

[0063] In some embodiments, the thermal-mechanical sequential coupling analysis method in step 10 includes:

[0064] Step a: Select the fire-exposed surfaces on the webs and lower flanges on both sides, and select the corresponding fire temperature rise curve according to different building project types to heat the fire-exposed surfaces. Simulate the change of the internal temperature of the stainless steel core plate beam with time under the action of fire on three sides, and solve the structural temperature field.

[0065] Step b: Apply the obtained temperature field to the stainless steel core plate beam subjected to a certain external load, and analyze the mechanical response of the stainless steel core plate beam under the action of constant load and temperature increase, including: the change in the mid-span deflection of the stainless steel core plate beam with the increase of time or temperature.

[0066] Step c: Record the temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time. v The fire exposure time includes 1 hour, 1.5 hours, and 2 hours; record the critical temperature T of the lower flange when the stainless steel core plate beam reaches the fire failure state u The fire failure state is determined by the mid-span bending deformation and the mid-span bending deformation rate of the stainless steel core plate beam. When the mid-span bending deformation exceeds the limit complete deformation When the stainless steel core plate beam reaches the fire failure state; when the mid-span bending deformation exceeds 1 / 30 of the clear span length, when the mid-span bending deformation rate exceeds the limit bending deformation rate When the fire is too severe, the stainless steel core beam also reaches the state of failure due to fire.

[0067] It should be understood that the present invention is not limited to the exact construction described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A fire protection design method for a stainless steel core beam structure, characterized in that: include: Step 20: Determine the load ratio η and the critical temperature T of the lower flange when the stainless steel core beam reaches the fire failure state u relationship; According to the fire response data of the lower flange when the stainless steel core plate beam structure fails under different load ratios η, T u The relationship between η and η is used to determine the parameter value and obtain formula (1): T u =-1978.6th 2 +1021.6th+737.83 (1) Step 30: Determine the fire protection equivalent thermal resistance R i The temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time v relationship; According to different fire exposure time and different fire protection equivalent thermal resistance R i The fire response data of the lower flange of the stainless steel core beam under the action of T v With R i The relationship between , determine the parameter value, and get formula (2): R i =αln(T v )+β (2) Among them, the values ​​of parameters α and β are different under different fire exposure times; Step 40: Determine the load ratio η and the fire protection equivalent thermal resistance R i relationship; When T v Reach T u When the fire protection equivalent thermal resistance required for the stainless steel core beam to reach the fire resistance limit under specific load ratio conditions is obtained according to formula (1) and formula (2): R i =αln(-1978.6th 2 +1021.6n+737.83)+b (3) Step 50: Calculate the thickness d of the fire protection layer of the stainless steel core beam that meets the fire resistance grade requirements of the building project i ; Determine the fire resistance limit of the stainless steel core plate beam structure based on the fire resistance grade requirements of the construction project; determine the values ​​of parameters α and β based on the fire resistance limit of the stainless steel core plate beam structure; and determine the value of the load ratio η that meets the requirements of the construction project based on the specifications of the stainless steel core plate beam used in the construction project and the initial load design value of the construction project components; According to formula (3), the equivalent thermal resistance R of the stainless steel core beam fire protection that meets the fire resistance grade requirements of the building project is calculated. i The value of Determine the equivalent heat transfer coefficient λ of the fire protection material according to the specifications of the fire protection material used in the construction project i The value of fire protection layer thickness d of stainless steel core beam that meets the fire resistance grade requirements of construction engineering is calculated. i =R i ·λ i .

2. The fire protection design method for stainless steel core beam structure according to claim 1, characterized in that: Before step 20, also include: Step 10: Obtain fire response data of the stainless steel core beam through finite element simulation; Finite element software ABAQUS was used to establish a stainless steel core beam model. The stainless steel core beam includes: upper flange, web, core tube, thermal and acoustic insulation material, fire protection layer, and lower flange. Each component is connected into a whole using Tie constraints. Set the model's thermal parameters, boundary conditions, mesh size, and element type. Based on historical construction project data, set multiple operating conditions, including fire exposure time, load ratio, and fire protection equivalent thermal resistance. The load ratio is the ratio of the load on the stainless steel core beam during fire to the ultimate load of the stainless steel core beam at room temperature. Finite element simulation was performed using the thermal-mechanical sequential coupling analysis method to obtain the fire response data of the stainless steel core plate beam under different working conditions, including: the critical temperature of the lower flange of the stainless steel core plate beam when it reaches the fire failure state, and the temperature of the lower flange of the stainless steel core plate beam after a certain fire exposure time.

3. The fire protection design method for stainless steel core beam structure according to claim 2, characterized in that: Step 30 also includes: Determine the fire protection equivalent heat R i The temperature T of the lower flange of the stainless steel core beam after 1 hour, 1.5 hours and 2 hours of fire v relationship; In formula (2), 1 hour of fire corresponds to α = -0.316, β = 2.1554, 1.5 hours of fire corresponds to α = -0.43, β = 2.981, and 2 hours of fire corresponds to α = -0.524, β = 3.6608; Step 50 also includes: determining the fire exposure time according to the fire resistance limit of the stainless steel core beam structure, and selecting the corresponding values ​​of parameters α and β.

4. The fire protection design method for a stainless steel core beam structure according to claim 3, characterized in that: Step 50 also includes: According to the historical data corresponding to the specifications of stainless steel core plate beams used in construction projects, the ultimate load value q of the stainless steel core plate beams at room temperature is obtained. room , according to the initial load design value of the construction engineering beam component, determine the load design value q of the stainless steel core plate beam when it is exposed to fire fire , calculate the load ratio that meets the needs of the construction project 5. The fire protection design method for stainless steel core beam structure according to claim 4, characterized in that: The thermal-mechanical sequential coupling analysis method in step 10 includes: Step a: Select the fire-exposed surfaces on the webs and lower flanges on both sides, select the corresponding fire temperature rise curve according to different building project types, and heat the fire-exposed surfaces. Simulate the time-dependent temperature change of the stainless steel core beam under the action of fire on three sides, and solve the structural temperature field. Step b: Applying the obtained temperature field to a stainless steel core plate beam subjected to a certain external load, analyzing the mechanical response of the stainless steel core plate beam under the action of constant load and temperature increase, including: the change in the mid-span deflection of the stainless steel core plate beam with the increase of time or temperature; Step c: Record the temperature T of the lower flange of the stainless steel core beam after a certain fire exposure time. v The fire exposure time includes 1 hour, 1.5 hours, and 2 hours; record the critical temperature T of the lower flange when the stainless steel core plate beam reaches the fire failure state u The fire failure state is determined by the mid-span bending deformation and the mid-span bending deformation rate of the stainless steel core plate beam. When the mid-span bending deformation exceeds the limit complete deformation When the stainless steel core plate beam reaches the fire failure state; when the mid-span bending deformation exceeds 1 / 30 of the clear span length, when the mid-span bending deformation rate exceeds the limit bending deformation rate When the fire is too severe, the stainless steel core beam also reaches the state of failure due to fire.

6. A computer device, characterized in that: include: a memory for storing instructions; The processor is configured to call the instructions stored in the memory to execute the fire protection design method for a stainless steel core plate beam structure according to any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that Instructions are stored, and when the instructions are executed by the processor, the fire protection design method for the stainless steel core plate beam structure according to any one of claims 1 to 5 is executed.

Images