Construction method of building steel structure engineering

Abstract

The invention discloses a construction method of a building steel structure project, which relates to the technical field of steel structures and comprises the following steps of material preparation, arrangement before construction, steel structure preheating, welding energy control, evaluation of heat absorbed by a weld joint in unit length by using a welding heat input algorithm, comprehensive evaluation, and construction of the steel structure project after welding is completed. The welding seam quality is evaluated by utilizing a comprehensive evaluation algorithm and combining welding line energy to obtain a welding seam score and welding seam finishing, the welding seam preheating temperature can be adjusted according to different steel properties and welding modes, the accuracy of the welding seam preheating temperature is guaranteed, different influence factors are introduced into a welding heat input algorithm, and the welding quality is improved. And in a comprehensive evaluation algorithm, factors such as the cooling speed of the welding line, the welding line energy and the welding line area are combined for evaluation, the unified standard of welding line quality evaluation is achieved, and the effect of improving the overall quality of a steel structure project is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of steel structures, in particular to a construction method for a building steel structure project. Background Art

[0002] Steel structures are mainly composed of steel beams, steel columns, steel trusses and other components made of steel and steel plates. The components or parts are usually connected by welds, bolts or rivets. Because of its light weight and simple construction, it is widely used in large factories, venues, super high-rise buildings and other fields. In the construction of construction projects, the use of steel structure engineering for design can not only make the construction project have a larger span space, but also have the advantages of convenient installation and low cost. With the further development of my country's urbanization process, the number of high-rise buildings will increase dramatically, which puts higher requirements on the design of steel structure engineering.

[0003] At present, in the welding process of steel structure engineering, a fixed preheating temperature is usually adopted, and the calculation of welding heat input often relies on fixed current and voltage parameters, without considering the actual situation of steel and the influence of the environment, resulting in inaccurate calculation of preheating temperature and heat input, affecting the welding quality. After welding is completed, there is a lack of standards for evaluating the quality of welds, resulting in uneven weld quality, which reduces the overall quality of steel structure engineering. Summary of the invention

[0004] The purpose of the present invention is to provide a construction method for a building steel structure project, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a construction method for a building steel structure project, comprising the following steps: Material preparation, preparation of welding equipment, purchase of steel according to construction requirements, and inspection of the steel. After passing the inspection, pre-treatment and cleaning of the steel; Arrange before construction, build working platform and support structure, check grounding and insulation of welding equipment, ensure welding machine, gas flow meter and welding fixture operate normally, and ensure safety and stability of construction site; Preheating of steel structures, using weld preheating algorithm to evaluate weld preheating temperature D of steel welding parts pre , and preheat the steel welding parts to reduce the thermal stress and residual deformation generated during the welding process; Welding energy control: After the steel welding part is preheated, the heat absorbed by the weld per unit length is evaluated using the welding heat input algorithm to obtain the welding line energy Q, and then welding is carried out. During the welding process, the current and voltage data are monitored in real time; Comprehensive evaluation: after welding is completed, the weld quality is evaluated by using a comprehensive evaluation algorithm combined with the welding line energy Q to obtain a weld score S, and the minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, rework is performed and the data in the welding heat input algorithm is adjusted; Weld trimming: After the steel structure welding is completed, the weld should be trimmed and cleaned to remove welding slag and oxides to ensure that the weld is flat and smooth.

[0006] Optionally, the pretreatment cleaning includes rust removal, oil removal, high-pressure water washing and drying, and a protective primer is applied to the steel after the pretreatment is completed.

[0007] Optionally, the weld preheating algorithm process in the steel structure preheating step is as follows: ; Where D pre is the weld preheat temperature; D base It is the basic preheating temperature, which is determined by the type of steel; C is the carbon content of steel; V is the welding speed; H is the thickness of the steel; R is the welding method coefficient, and its value range is 1 to 2.

[0008] Optionally, the welding heat input algorithm process in the welding energy control step is as follows: ; Where Q is the welding line energy; I is the welding current; U is the welding voltage; J is the welding time; μ is the welding efficiency coefficient, ranging from 0.5 to 1; W×(D env -D base )×L is the ambient heat adjustment; W is the environmental impact coefficient, which is 0.5; D env is the ambient temperature; D base is the weld preheat temperature; L is the weld length.

[0009] Optionally, the comprehensive evaluation algorithm process is as follows: ; Where S is the weld score; T is the cooling rate of the weld, T max is the maximum cooling rate of the weld; α is the cooling rate influence coefficient, and its value range is 0.3; Q is the welding energy, Q sta is the standard welding energy input; β is the influence coefficient of welding line energy, and its value range is 0.4; A is the weld area; A min is the minimum value of the weld area, A max is the maximum value of the weld area; γ is the weld area influence coefficient, and its value range is 0.3; Specific: ; Where D start is the temperature at the start of the weld; D end is the temperature of the weld when it cools to room temperature; t cool is the time taken for cooling; The minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, it means that the current steel structure welding quality is lower than the construction project requirements. At this time, the steel structure needs to be reworked. At the same time, the environmental impact coefficient W in the welding heat input algorithm is increased to increase the influence of the welding environment on the welding line energy Q and the weld score S. Specifically: ; Where W is the environmental impact coefficient; Y is the minimum threshold and S is the weld score.

[0010] Optionally, in the welding energy control step, the welder wears protective equipment before welding, and the protective equipment includes a welding mask and protective gloves.

[0011] Optionally, in the weld finishing step, after the welding of the steel structure is completed, ultrasonic testing is used to inspect the inside of the weld, and the weld surface is checked using tools such as a magnifying glass and a vernier caliper, and the appearance quality of the weld is recorded, and the appearance quality includes the flatness, color and gloss of the weld.

[0012] Optionally, after the steel structure welding is completed, the data in the weld preheating algorithm, welding heat input algorithm and comprehensive evaluation algorithm are stored and used as reference data in subsequent welding.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses the weld preheating temperature D in the weld preheating algorithm pre It will be adjusted according to different steel properties and welding methods to ensure the weld preheating temperature D pre The accuracy of the weld preheating temperature Dpre Preheat the steel to ensure that the weld reaches an appropriate initial temperature before welding. Then, the welding line energy Q is obtained through the welding heat input algorithm. The voltage, current and other data of the welding equipment are adjusted according to the welding line energy Q to ensure that the energy absorbed by the steel is consistent with the welding line energy Q. At the same time, the environmental impact coefficient W and welding efficiency coefficient μ are introduced into the welding heat input algorithm. The welding line energy Q can be adjusted according to the actual situation to ensure the accuracy of the welding line energy Q and improve the welding quality.

[0014] 2. The present invention evaluates the weld quality through a comprehensive evaluation algorithm combined with the welding line energy Q to obtain a weld score S. In the comprehensive evaluation algorithm, the weld quality is evaluated in combination with factors such as the cooling rate of the weld, the welding line energy Q and the weld area, and the result is quantified to reduce the deviation caused by subjective judgment, so that construction personnel can intuitively understand the weld quality and achieve a unified standard for weld quality evaluation. When the weld score S is less than Y, rework is performed to keep the weld quality consistent and improve the overall quality of the steel structure project. The value of the weld score S will change the environmental impact coefficient W, and optimization and adjustment are performed according to actual conditions to make the result more accurate. The algorithms can influence each other and jointly improve the welding quality of steel structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] For examples, see Figure 1 This embodiment provides a construction method for a building steel structure project, comprising the following steps: Material preparation, preparation of welding equipment, purchase of steel according to construction requirements, and inspection of the steel. After passing the inspection, pre-treatment and cleaning of the steel; Arrange before construction, build working platform and support structure, check grounding and insulation of welding equipment, ensure welding machine, gas flow meter and welding fixture operate normally, and ensure safety and stability of construction site; Preheating of steel structures: using the weld preheating algorithm to evaluate the preheating temperature D of the steel welding part, and preheating the steel welding part to reduce the thermal stress and residual deformation generated during the welding process; Welding energy control: After the steel welding part is preheated, the heat absorbed by the weld per unit length is evaluated using the welding heat input algorithm to obtain the welding line energy Q, and then welding is carried out. During the welding process, the current and voltage data are monitored in real time; Before welding, welders must wear protective equipment, including welding masks and protective gloves, to ensure their personal safety; Comprehensive evaluation: after welding is completed, the weld quality is evaluated by using a comprehensive evaluation algorithm combined with the welding line energy Q to obtain a weld score S, and the minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, rework is performed and the data in the welding heat input algorithm is adjusted; Step S6: Weld seam trimming: After the steel structure welding is completed, the weld seam is trimmed and cleaned to remove welding slag and oxides to ensure that the weld seam is flat and smooth.

[0018] In this embodiment, by pre-treating and cleaning the steel, impurities and dust on the surface of the steel can be removed, and the subsequent welding quality can be improved. After the steel is pre-treated, the weld preheating temperature D of the steel is obtained by the weld preheating algorithm. pre , and in the weld preheating algorithm the weld preheating temperature D pre It will be adjusted according to different steel properties and welding methods to ensure the weld preheating temperature D pre The accuracy of the weld preheating temperature D pre Preheat the steel to ensure that the weld reaches an appropriate initial temperature before welding, reduce the thermal stress and residual deformation generated during the welding process, avoid the weld and its surrounding areas from becoming brittle or reducing the structural bearing capacity due to heat, and improve the quality of the entire steel structure welded parts. Then, the welding line energy Q is obtained through the welding heat input algorithm. The voltage, current and other data of the welding equipment are adjusted according to the welding line energy Q to ensure that the energy absorbed by the steel is consistent with the welding line energy Q. At the same time, the environmental impact coefficient W and the welding efficiency coefficient μ are introduced into the welding heat input algorithm. The welding line energy Q is adjusted according to the actual situation to ensure the accuracy of the welding line energy Q and improve the subsequent welding quality.

[0019] Finally, the weld quality is evaluated through a comprehensive evaluation algorithm combined with the welding line energy Q to obtain the weld score S. The comprehensive evaluation algorithm combines different factors of the weld to evaluate the weld, and quantifies the results to reduce the deviation caused by subjective judgment, so that construction personnel can intuitively understand the weld quality. By setting the minimum threshold value Y for the weld score S, when the weld score S is less than Y, rework is performed to keep the weld quality consistent and improve the overall quality of the steel structure project.

[0020] Furthermore, the pretreatment cleaning includes rust removal, oil removal, high-pressure water washing and drying, and the steel is coated with a protective primer after the pretreatment is completed.

[0021] Specifically, in the rust removal process, different rust removal methods can be selected according to the specific steel, including mechanical rust removal, chemical rust removal and electrochemical rust removal. Electrochemical rust removal uses the principle of electrolysis for rust removal, such as anodic oxidation and cathodic protection, which is used for rust removal of large components or components of complex shapes. Oil removal uses organic solvents such as alcohol to wipe the surface of the steel to remove oil stains, or uses alkaline detergents to react with grease to generate water-soluble substances to remove oil stains. After rust and oil removal of the steel, use a high-pressure water gun to rinse the surface of the steel to remove residues, and then place the steel in a well-ventilated environment to allow it to dry naturally, thereby completing the steel pretreatment and improving the surface quality of the steel for subsequent welding work.

[0022] Furthermore, the weld preheating algorithm process in the steel structure preheating step is as follows: ; Where D pre is the weld preheat temperature; D base It is the basic preheating temperature, which is determined by the type of steel. According to the welding characteristics of different materials, the basic temperature can be a fixed value, such as 50°C for low alloy steel and 100°C for high alloy steel; C is the carbon content of the steel. The higher the carbon content of the steel, the greater the risk of brittle cracks during welding, so the preheating temperature needs to be appropriately increased; V is the welding speed. The welding speed V affects the heat input. The faster the speed, the higher the preheating temperature to ensure sufficient melting and bonding. H is the thickness of the steel. The thicker the steel, the faster the heat diffuses, so the preheating temperature will increase with the thickness. R is the welding method coefficient, ranging from 1 to 2; Specifically, the value for manual arc welding is 1, the value for gas metal arc welding is 1.2, and the value for argon tungsten arc welding is 1.5; Specifically, the weld preheating temperature D pre It will be adjusted according to different steel properties and welding methods, and the weld preheating temperature will be increased. pre To ensure the accuracy of the weld, preheat the steel weld to ensure that the weld reaches the initial temperature before welding, avoiding the brittleness of the weld and its surrounding areas and the reduction of structural bearing capacity due to heat. Preheating can also slow down the cooling rate in the key temperature range during the weld cooling process, prevent excessive hardening and reduce the ductility of the weld and heat-affected zone, avoid hydrogen-induced cracks, and improve the quality of steel structure welds.

[0023] Furthermore, the welding heat input algorithm process in the welding energy control step is as follows: ; Where Q is the welding line energy; I is the welding current; U is the welding voltage; J is the welding time; μ is the welding efficiency coefficient, ranging from 0.5 to 1; W×(D env -D base )×L is the ambient heat adjustment; W is the environmental impact coefficient, which is 0.5; D env is the ambient temperature; D base is the weld preheat temperature; L is the weld length; Specifically, the welding line energy Q is the heat input by the welding equipment to the weld per unit length during welding. By adding factors such as the environmental impact coefficient W and the welding efficiency coefficient μ to the welding heat input algorithm, the calculation of the welding line energy Q is more accurate, ensuring that the heat transfer during the welding process is in line with the actual situation, reducing weld defects caused by improper heat input, and improving welding quality.

[0024] Furthermore, the comprehensive evaluation algorithm process is as follows: ; Where S is the weld score; T is the cooling rate of the weld, T max is the maximum cooling rate of the weld; The cooling rate affects the hardness, toughness and strength of the weld. The faster the cooling rate, the finer the grains, which increases the hardness of the weld. Rapid cooling can cause greater internal stress inside the weld, which reduces its toughness. α is the cooling rate influence coefficient, and its value range is 0.3; Q is the welding line energy, Q sta is the standard welding energy input; β is the influence coefficient of welding line energy, and its value range is 0.4; A is the weld area; A min is the minimum value of the weld area, A max is the maximum value of the weld area; γ is the weld area influence coefficient, and its value range is 0.3; Specific: ; Where D start is the temperature at the start of the weld; D end is the temperature of the weld when it cools to room temperature; t cool is the time taken for cooling; The minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, the welding quality of the current steel structure is lower than the requirements of the construction project. At this time, the steel structure needs to be reworked. At the same time, the environmental impact coefficient W in the welding heat input algorithm is increased to increase the influence of the welding environment on the welding line energy Q and the weld score S. Specifically: ; Where W is the environmental impact coefficient; Y is the minimum threshold; S is the weld score.

[0025] By setting the weld score S to be less than Y, the environmental impact coefficient W in the welding heat input algorithm changes, so that the method can be optimized and adjusted according to the actual situation, so that the results can be more accurate, and the algorithms can influence each other to jointly improve the welding quality of steel structures. Specifically, the weld quality is evaluated through a comprehensive evaluation algorithm combined with the welding line energy Q to obtain a weld score S. In the comprehensive evaluation algorithm, the weld quality is evaluated in combination with factors such as the weld cooling rate, welding line energy Q and weld area, and the results are quantified to reduce the deviation caused by subjective judgment, so that construction personnel can intuitively understand the weld quality and realize the standard for weld quality evaluation, so as to evaluate other welds in the future. Then, by setting the minimum threshold value of the weld score S to Y, when the weld score S is less than Y, rework is performed to keep the weld quality consistent and improve the overall quality of the steel structure project.

[0026] Furthermore, after the welding of the steel structure is completed, ultrasonic testing is used to inspect the inside of the weld, and magnifying glasses, vernier calipers and other tools are used to check the weld surface, and the appearance quality of the weld is recorded. The appearance quality includes the flatness, color and gloss of the weld. Specifically, ultrasonic testing can effectively identify defects inside the weld, such as pores, cracks and inclusions, to ensure the structural integrity and safety of the weld, and can detect it without damaging the weld. The color and gloss of the weld can reflect the heating and cooling of the material during the welding process. The appearance quality is recorded in detail to provide a basis for subsequent quality analysis and process improvement.

[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A construction method for a building steel structure project, characterized in that: The following steps are involved: Step S1: Material preparation, preparing welding equipment, purchasing steel according to construction requirements, and inspecting it. After passing the inspection, pre-treat and clean the steel; Step S2: Arrangement before construction, build the working platform and support structure, check the grounding and insulation conditions of the welding equipment, ensure the normal operation of the welding machine, gas flow meter, and welding fixture, and ensure the safety and stability of the construction site; Step S3: Preheating the steel structure, using the weld preheating algorithm to estimate the weld preheating temperature D of the steel welding part pre , and preheat the steel welding parts to reduce the thermal stress and residual deformation generated during the welding process; Step S4: welding energy control. After the steel welding part is preheated, the heat absorbed by the weld per unit length is evaluated using the welding heat input algorithm to obtain the welding line energy Q. Then welding is performed, and the current and voltage data are monitored in real time during the welding process. Step S5: Comprehensive evaluation: after welding is completed, the weld quality is evaluated by using a comprehensive evaluation algorithm and combining the welding line energy Q to obtain a weld score S, and the minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, rework is performed and the data in the welding heat input algorithm is adjusted; Step S6: Weld seam trimming: After the steel structure welding is completed, the weld seam is trimmed and cleaned to remove welding slag and oxides to ensure that the weld seam is flat and smooth.

2. The construction method of building steel structure engineering according to claim 1, characterized in that: The pretreatment cleaning includes rust removal, oil removal, high-pressure water washing and drying. After the steel material is pretreated, a protective primer is applied.

3. The construction method of the building steel structure engineering according to claim 2 is characterized in that: The weld preheating algorithm process in the steel structure preheating step is as follows: ； Where D pre is the weld preheat temperature; D base It is the basic preheating temperature, which is determined by the type of steel; C is the carbon content of steel; V is the welding speed; H is the thickness of the steel; R is the welding method coefficient, and its value range is 1 to 2.

4. The construction method of building steel structure engineering according to claim 3 is characterized by: The welding heat input algorithm process in the welding energy control step is as follows: ； Where Q is the welding line energy; I is the welding current; U is the welding voltage; J is the welding time; μ is the welding efficiency coefficient, ranging from 0.5 to 1; W×(D env -D base )×L is the ambient heat adjustment; W is the environmental impact coefficient, which is 0.5; D env is the ambient temperature; D base is the weld preheat temperature; L is the weld length.

5. The construction method of building steel structure engineering according to claim 4 is characterized in that: The comprehensive evaluation algorithm process is as follows: ； Where S is the weld score; T is the cooling rate of the weld, T max is the maximum cooling rate of the weld; α is the cooling rate influence coefficient, and its value range is 0.3; Q is the welding line energy, Q sta is the standard welding energy input; β is the influence coefficient of welding line energy, and its value range is 0.4; A is the weld area; A min is the minimum value of the weld area, A max is the maximum value of the weld area; γ is the weld area influence coefficient, and its value range is 0.3; Specific: ； Where D start is the temperature at the start of the weld; D end is the temperature of the weld when it cools to room temperature; t cool is the time taken for cooling; The minimum threshold of the weld score S is set to Y. When the weld score S is less than Y, it means that the current steel structure welding quality is lower than the construction project requirements. At this time, the steel structure needs to be reworked. At the same time, the environmental impact coefficient W in the welding heat input algorithm is increased to increase the influence of the welding environment on the welding line energy Q and the weld score S. Specifically: ； Where W is the environmental impact coefficient; Y is the minimum threshold and S is the weld score.

6. The construction method of building steel structure engineering according to claim 1, characterized in that: In the welding energy control step, the welder wears protective equipment before welding, and the protective equipment includes a welding mask and protective gloves.

7. The construction method of building steel structure engineering according to claim 1, characterized in that: In the weld finishing step, after the steel structure welding is completed, ultrasonic testing is used to detect the inside of the weld, and a magnifying glass, vernier caliper and other tools are used to check the weld surface, and the appearance quality of the weld is recorded. The appearance quality includes the flatness, color and gloss of the weld.

8. The construction method of building steel structure engineering according to claim 1, characterized in that: After the steel structure welding is completed, the data in the weld preheating algorithm, welding heat input algorithm and comprehensive evaluation algorithm are stored and used as reference data in subsequent welding.

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