Low-temperature environment large-span steel structure closure construction method

Abstract

The application discloses a large-span steel structure closure construction method in a low-temperature environment, and is based on a design closure temperature, a plurality of key stress components of the large-span steel structure are screened out through a structure design software; a heating piece is coated outside the key stress components and a temperature measuring piece is installed; a controller is connected to the heating piece and the temperature measuring piece; the temperature measuring piece collects real-time temperatures of the key stress components; the controller acquires the real-time temperatures, and the heating piece is controlled by the controller to heat the key stress components to the design closure temperature; and the large-span steel structure is subjected to closure supplemental rod component welding. The application solves the problem that long-span steel structures are not suitable for closure in northern regions of China due to low and long winter temperatures.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to a method for the closure construction of large-span steel structures under low-temperature conditions. Background Technology

[0002] Large-span steel structures are a common structural form in building engineering, widely used in conference and exhibition centers, stadiums, airport terminals, hangars, and other buildings requiring large, column-free spaces. Due to the high coefficient of linear expansion of steel, it is highly sensitive to temperature. In regions with significant temperature variations, temperature is a key factor determining the overall deformation and component cross-sectional size of long-span steel structures. To prevent excessive deformation and additional stress in long-span steel structures under temperature effects, which could endanger structural safety and usability, structural designers, based on the long-term average temperature and other climatic conditions of the building's location, will propose specific requirements for the closure temperature of long-span steel structures after precise calculations. Considering overall economy and safety, the closure temperature of long-span steel structures is typically within a certain range based on the annual average temperature of the building's location. However, in northern my country, there are generally large temperature differences and long, harsh winters, which limits the effective closure time for long-span steel structures. In particular, for long-span steel structures that have not been closed before winter, work must be suspended and the closure and subsequent construction must be carried out for nearly half a year until the closure temperature conditions are met. This has a significant impact on the project schedule and increases costs. In addition, the inability of the structure to be effectively closed under low winter conditions also poses safety hazards. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, a method for closure construction of large-span steel structures in low-temperature environments is provided to address the problem that the low and long winter temperatures in northern my country make it unsuitable for closure of large-span steel structures.

[0004] To achieve the above objectives, a method for the closure construction of large-span steel structures under low-temperature conditions is provided, comprising the following steps:

[0005] Based on the design closure temperature, several key load-bearing components of the large-span steel structure were selected using structural design software.

[0006] Heating elements are wrapped around the outside of several key load-bearing components, and temperature measuring elements are installed.

[0007] Connect the controller to the heating element and the temperature measuring element;

[0008] The temperature measuring device collects the real-time temperature of the key stress-bearing component;

[0009] The controller acquires the real-time temperature and controls the heating element to raise the temperature of the key stress-bearing component to the designed closure temperature.

[0010] Welding of the closure and reinforcement components was carried out on the large-span steel structure.

[0011] Furthermore, the step of selecting multiple key load-bearing components of a large-span steel structure using structural design software includes:

[0012] Using the designed closure temperature as the initial temperature of the large-span steel structure, the structural design software is used to calculate and analyze the additional stress and deformation of the large-span steel structure under the action of heating and cooling, and the component with significant changes in additional stress and deformation under the action of temperature change is selected as the first key load-bearing component.

[0013] The design closure temperature is set as the initial temperature of the first key load-bearing component. The actual ambient temperature at the construction site during closure in a low-temperature environment is set as the initial temperature of the remaining components of the large-span steel structure. The additional stress and deformation of the large-span steel structure under the effects of heating and cooling are calculated and analyzed again. The component with significant changes in additional stress and deformation under temperature changes is selected as the second key load-bearing component. The first key load-bearing component and the second key load-bearing component selected through the two calculations and analyses are the key load-bearing components of the large-span steel structure.

[0014] Furthermore, the temperature measuring element is a temperature sensor.

[0015] Furthermore, the heating element includes:

[0016] Insulating pads are used to cover the key load-bearing components;

[0017] The heating wire is installed on the inner side of the insulation pad and is attached to the key load-bearing component;

[0018] Pipe clamps are fixed to the outside of the insulation pad.

[0019] The beneficial effects of this invention are that the method for closure construction of large-span steel structures in low-temperature environments allows the closure period to be set in winter during the construction of large-span steel structures. Even when the average ambient temperature is much lower than the design-given closure temperature, the closure construction can be carried out after heating and insulating the key load-bearing components of the structure using the method of this invention. This ensures structural safety while effectively shortening the construction cycle and creating good economic benefits. Attached Figure Description

[0020] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0021] Figure 1 This is a schematic diagram of the construction method for closure of a large-span steel structure under low-temperature conditions according to an embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the heating element according to an embodiment of the present invention.

[0023] Figure 3 This is a schematic diagram of the temperature measuring element according to an embodiment of the present invention.

[0024] Figure 4 This is a schematic diagram of a large-span steel structure according to an embodiment of the present invention. Detailed Implementation

[0025] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] Reference Figures 1 to 4 As shown, this invention provides a method for the closure construction of a large-span steel structure under low-temperature conditions, including the following steps:

[0028] S1. Based on the design closure temperature, several key load-bearing components of the large-span steel structure 1 were selected using structural design software.

[0029] See Figure 4 As shown, the large-span steel structure is a space truss structure.

[0030] When there are many components in a large-span steel structure, such as Figure 4 When designing a large-span steel structure as shown, in step 1, the structural design software identifies several key load-bearing components of the large-span steel structure 1, including:

[0031] S11: Using the design closure temperature as the initial temperature of the large-span steel structure 1, the additional stress and deformation of the large-span steel structure 1 under the action of heating and cooling are calculated and analyzed using structural design software such as Midas, SAP2000, ETABS, ANSYS, YJK, and PKPM. The components with significant changes in additional stress and deformation under temperature change are selected as the first key load-bearing components.

[0032] S12: The design closure temperature is set as the initial temperature of the first critical load-bearing component. The actual ambient temperature at the construction site during closure in a low-temperature environment is set as the initial temperature of the remaining components of the large-span steel structure 1. The additional stress and deformation of the large-span steel structure 1 under the effects of heating and cooling are calculated and analyzed again. The component with significant changes in additional stress and deformation under temperature change is selected as the second critical load-bearing component. The first and second critical load-bearing components selected through the two calculations and analyses are the critical load-bearing components of the large-span steel structure 1.

[0033] Screening method for key load-bearing components:

[0034] 1) Using the closure temperature required by the design as the initial temperature of the component, the additional stress and deformation of the structure under the action of temperature rise and temperature drop are calculated and analyzed by the structural design software, and the component with significant changes in additional stress and deformation under the action of temperature is selected as the first key load-bearing component.

[0035] 2) Set the closure temperature required by the design as the initial temperature of the selected first key load-bearing component, and set the actual ambient temperature at the construction site during closure in a low-temperature environment as the initial temperature of the remaining components. Calculate and analyze the additional stress and deformation of the structure under the action of temperature rise and temperature drop again, and select the component with significant changes in additional stress and deformation under the action of temperature as the second key load-bearing component.

[0036] 3) The first and second key components selected through two calculations and analyses are the key load-bearing components of this structure.

[0037] For structures with a small number of components, all components are critical load-bearing components.

[0038] S2. The heating element 2 is wrapped around the outside of several key load-bearing components and the temperature measuring element 3 is installed.

[0039] In this embodiment, the temperature measuring element 3 is a temperature sensor. Specifically, the temperature sensor includes a temperature sensor body, a magnetic arch frame 31, and a sliding rod 32. Sliding grooves are formed on opposite sides of both ends of the magnetic arch frame. The two ends of the sliding rod slide within the two sliding grooves of the magnetic arch frame, respectively. Multiple wire holes are formed in the middle of the sliding rod. The temperature measuring element and the heating element are connected to a controller via wires. The wires are movably threaded through the wire holes.

[0040] A push spring 34 connects the slide rod to the top of the magnetic arch. A base 33 is formed on the side of the slide rod away from the top of the magnetic arch. The temperature sensor body is mounted on the base.

[0041] Magnetic arches are components that are magnetically attracted to long-span steel structures. The magnetic arches are made of magnets.

[0042] In this embodiment, the heating element 2 includes: a heat insulation pad 21, a heating wire, and a pipe clamp 22.

[0043] The insulation pad 21 covers the critical load-bearing component. The heating wire is installed on the inside of the insulation pad. The heating wire is attached to the critical load-bearing component. The pipe clamp 22 is fixed to the outside of the insulation pad.

[0044] S3. Connect the controller 4 to the heating element 2 and the temperature measuring element 3.

[0045] The temperature measuring element and heating element are combined with the controller to form an intelligent heating and temperature monitoring control device. The temperature measuring element and heating element are covered on the outer surface of the selected key load-bearing components and all nodes to ensure that the flexible heating element is in close contact with the steel components of the large-span steel structure. The wires connecting the various components and their connection lines to the controller are limited through the wire holes.

[0046] First, test the continuity of the wires between each temperature sensor and heating element, as well as their connection to the controller, and replace any non-energized or damaged components and wires. Then, debug the intelligent heating and temperature monitoring control device, ensuring its heating, temperature measurement, and intelligent temperature control functions operate normally.

[0047] S4, Temperature measuring element 3 collects the real-time temperature of key load-bearing components.

[0048] S5 and controller 4 acquire real-time temperature and control heating element 2 to heat key stress components to the designed closure temperature.

[0049] The temperature control target value of the intelligent heating and temperature monitoring control device is set to the closure temperature required by the design. The heating function is started and monitored in real time. After the temperature of the key load-bearing components of the structure reaches the closure temperature range required by the design and stabilizes for 10 minutes, the heating ends and enters the temperature stabilization control state.

[0050] S6. Welding of the closure reinforcement components for the large-span steel structure 1.

[0051] Protective devices such as fire-receiving hoppers are installed around the closure and repair components to prevent welding slag from splashing and falling, which could damage the heating and temperature measuring components and connecting wires during the welding process.

[0052] According to the closure sequence, the supplementary rods of the closure parts are welded in sequence according to the corresponding welding process requirements until all components are welded together.

[0053] S7. Inspection and repair of closure weld seams.

[0054] According to the relevant requirements for welds, the welds at the closure section are subjected to flaw detection. Any welds that do not meet the relevant requirements are repaired in a timely manner and then re-inspected until the quality of all closure repair welds meets the relevant requirements.

[0055] S8. (Unloading and Cooling) Remove the covering heating and temperature measuring components, and the closure is complete.

[0056] Stop heating and allow the structure to cool naturally. Then remove the heating and temperature measuring components covering the outer surface of the structural members, so that the structure is fully exposed to the natural environment and its stress state under natural low temperature conditions is restored. The structural closure is then complete.

[0057] The present invention provides a method for constructing large-span steel structures under low-temperature conditions. During the construction of large-span steel structures, the closure period can be set in winter. Even when the average ambient temperature is much lower than the design-given closure temperature, the closure construction can be carried out after heating and insulating the key load-bearing components of the structure using the method of the present invention. This ensures structural safety while effectively shortening the construction period and creating good economic benefits.

[0058] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A method for closure construction of a large-span steel structure under low-temperature conditions, characterized in that, Includes the following steps: Based on the design closure temperature, several key load-bearing components of the large-span steel structure were selected using structural design software. Heating elements are wrapped around the exterior of several key load-bearing components, and temperature measuring elements are installed thereon. Connect the controller to the heating element and the temperature measuring element; The temperature measuring device collects the real-time temperature of the key stress-bearing component; The controller acquires the real-time temperature and controls the heating element to raise the temperature of the key stress-bearing component to the designed closure temperature. Welding of closure reinforcement components was carried out on the large-span steel structure; The steps for selecting multiple key load-bearing components of a large-span steel structure using structural design software include: Using the designed closure temperature as the initial temperature of the large-span steel structure, the structural design software is used to calculate and analyze the additional stress and deformation of the large-span steel structure under the action of heating and cooling, and the component with significant changes in additional stress and deformation under the action of temperature change is selected as the first key load-bearing component. The design closure temperature is set as the initial temperature of the first key load-bearing component. The actual ambient temperature at the construction site during closure in a low-temperature environment is set as the initial temperature of the remaining components of the large-span steel structure. The additional stress and deformation of the large-span steel structure under the effects of heating and cooling are calculated and analyzed again. The component with significant changes in additional stress and deformation under temperature changes is selected as the second key load-bearing component. The first key load-bearing component and the second key load-bearing component selected through the two calculations and analyses are the key load-bearing components of the large-span steel structure.

2. The method for closure construction of large-span steel structures under low-temperature conditions according to claim 1, characterized in that, The temperature measuring element is a temperature sensor.

3. The method for closure construction of large-span steel structures under low-temperature conditions according to claim 1, characterized in that, The heating element includes: Insulating pads are used to cover the key load-bearing components; The heating wire is installed on the inner side of the insulation pad and is attached to the key load-bearing component; Pipe clamps are fixed to the outside of the insulation pad.

Images