Calculation system

Abstract

This invention provides a calculation system capable of determining the reduction in manufacturing costs of steel structures when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes. [Solution] The calculation system 10 for calculating the reduction rate of manufacturing costs in a steel frame structure composed of connected steel pipe columns and beams calculates the reduction rate of manufacturing costs of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes, based on the weight reduction rate of the steel pipe columns, the ratio of the material cost of hot-formed steel pipes to the material cost of cold-formed steel pipes for steel pipe columns, the ratio of the processing cost of cold-formed steel pipes to the material cost of cold-formed steel pipes for steel pipe columns, the ratio of the processing cost of hot-formed steel pipes to the material cost of cold-formed steel pipes for steel pipe columns, the ratio of the material cost of beams to the material cost of cold-formed steel pipes for steel pipe columns, and the ratio of the weight of beams to the weight of cold-formed steel pipes for steel pipe columns.

Description

Technical Field

[0001] The present invention is a system for calculating the reduction rate of the manufacturing cost of a steel frame structure composed of connecting a steel pipe column and a beam.

Background Art

[0002] Conventionally, in a steel frame structure composed of connecting a steel pipe column and a beam, a through diaphragm type column-beam joint structure as shown in Patent Document 1 and a non-diaphragm type column-beam joint structure as shown in Patent Document 2 are formed. In such a column-beam joint structure, a cold-formed square steel pipe (hereinafter referred to as "cold-formed steel pipe") and a hot-formed square steel pipe (hereinafter referred to as "hot-formed steel pipe") are used as the column materials of the steel pipe column.

[0003] Since the unit material cost of the cold-formed steel pipe is lower than that of the hot-formed steel pipe, the manufacturing cost of the steel frame structure can be suppressed. However, the cold-formed steel pipe has restrictions on the types of steel materials that can be used depending on the seismic calculation route (Route 1-1, Route 1-2, Route 2, Route 3) according to the scale of the steel frame structure. In particular, in Route 2, the cold-formed steel pipe needs to ensure a column-beam strength ratio of 1.5 or more, and it is necessary to increase the column cross-sectional size more than necessary with respect to the primary design stress. Therefore, the size of the steel pipe column increases, and the weight of the cold-formed steel pipe increases, which conversely increases the manufacturing cost of the steel frame structure. In addition, the cold-formed steel pipe needs to undergo a confirmation review of the structural calculation compliance determination by the judging agency depending on the seismic calculation route of the steel frame structure. Therefore, there is a problem that the manufacturing period of the steel frame structure using the cold-formed steel pipe is long.

[0004] On the other hand, hot-formed steel pipes have a higher material cost than cold-formed steel pipes, and are generally considered to be less cost-effective for manufacturing steel structures compared to cold-formed steel pipes. However, hot-formed steel pipes are exempt from the design constraints imposed on cold-formed steel pipes in seismic design, and unlike cold-formed steel pipes, there are no restrictions on the type of steel that can be used depending on the seismic calculation route for steel structures. In particular, in Route 2, hot-formed steel pipes do not have requirements such as column-beam strength ratio, so the size of the steel pipe columns can be reduced compared to cold-formed steel pipes, resulting in a reduction in weight. Therefore, the cost of hot-formed steel pipes can be reduced, thereby lowering the manufacturing cost of steel structures. In addition, hot-formed steel pipes do not need to undergo the above-mentioned confirmation review, so the construction period for steel structures can be shortened. Thus, when manufacturing steel structures, it is sometimes possible to reduce the manufacturing cost of steel structures by changing the column material from cold-formed steel pipes to hot-formed steel pipes. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2024-090174 [Patent Document 2] Japanese Patent Publication No. 2005-105757 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, when manufacturing steel frame structures, there was a problem in that there was no way to quantitatively determine to what extent the manufacturing costs of steel frame structures could be reduced by changing the column material of the steel pipe column from cold-formed steel pipe to hot-formed steel pipe.

[0007] Therefore, the present invention aims to provide a calculation system capable of calculating the reduction rate in manufacturing costs of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes. [Means for solving the problem]

[0008] The problems that this invention aims to solve are described above, and the means for solving these problems will now be explained.

[0009] In other words, the calculation system of the present invention is a calculation system for calculating the reduction rate of manufacturing costs in a steel frame structure constructed by connecting a beam to a steel pipe column and the beam connection portion of the steel pipe column, and includes weight data of the cold-formed steel pipe constituting the steel pipe column, material unit price data of the cold-formed steel pipe, processing cost data of the cold-formed steel pipe for processing the cold-formed steel pipe into the steel pipe column, weight data of a hot-formed steel pipe that can be constructed as the steel pipe column instead of the cold-formed steel pipe, material unit price data of the hot-formed steel pipe, and processing cost data of the hot-formed steel pipe for processing the hot-formed steel pipe into the steel pipe column The system comprises an input means for inputting cost data, weight data of the beam material constituting the beam, and material unit price data of the beam material, and a calculation means for calculating the reduction rate of manufacturing costs in the steel frame structure based on the data input by the input means, wherein the calculation means calculates the weight reduction rate of the steel pipe column when the hot-formed steel pipe is used instead of the cold-formed steel pipe based on the weight data of the cold-formed steel pipe and the weight data of the hot-formed steel pipe input by the input means, and the material of the cold-formed steel pipe input by the input means Based on the unit price data and the material unit price data of the hot-formed steel pipe, the ratio of the material cost of the hot-formed steel pipe column to the material cost of the cold-formed steel pipe column is calculated. Based on the material unit price data and the processing cost data of the cold-formed steel pipe input by the input means, the ratio of the processing cost for the cold-formed steel pipe column to the material cost of the cold-formed steel pipe column is calculated. Based on the material unit price data and the processing cost data of the hot-formed steel pipe input by the input means, the ratio of the material cost of the cold-formed steel pipe column to the processing cost for the cold-formed steel pipe column is calculated. The ratio of the processing cost of the hot-formed steel pipe to the steel pipe column is calculated, and based on the material unit price data of the cold-formed steel pipe and the material unit price data of the beam material input by the input means, the ratio of the material cost of the beam to the material cost of the cold-formed steel pipe column is calculated, and based on the weight data of the cold-formed steel pipe and the weight data of the beam material input by the input means, the ratio of the weight of the beam to the weight of the cold-formed steel pipe column is calculated, and the weight reduction rate of the steel pipe column and the ratio of the material cost of the hot-formed steel pipe column to the material cost of the cold-formed steel pipe column are calculated,This method calculates the reduction in manufacturing costs of the steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes, based on the ratio of the processing cost of cold-formed steel pipes to the material cost of the steel pipe columns, the ratio of the processing cost of hot-formed steel pipes to the material cost of the steel pipe columns, the ratio of the material cost of the beams to the material cost of the steel pipe columns, and the ratio of the weight of the beams to the weight of the steel pipe columns. [Effects of the Invention]

[0010] According to the calculation system of the present invention, the reduction rate in the manufacturing cost of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes can be easily confirmed. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an overview of the calculation system according to the present invention. [Modes for carrying out the invention]

[0012] The following describes embodiments of the present invention with reference to the drawings. First, the calculation system 10 according to the present invention will be described. However, the present invention is not limited to the calculation system 10 described below.

[0013] The calculation system 10 is a system for calculating the reduction rate in manufacturing costs of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes, in a steel frame structure composed of steel pipe columns and beams connected to the beam connection points of steel pipe columns.

[0014] Examples of steel structures for which the calculation system 10 calculates the reduction rate of manufacturing costs include low-rise buildings (e.g., a three-story logistics warehouse) and high-rise buildings (e.g., a seven-story office building). In the design of such steel structures, when selecting a seismic calculation route based on the size of the steel structure, it is necessary to choose whether the column material of the steel pipe columns constituting the steel structure is cold-formed steel pipe or hot-formed steel pipe. At this time, the calculation system 10 calculates the reduction rate of manufacturing costs of the steel structure to determine whether hot-formed steel pipe should be used as the steel pipe column instead of cold-formed steel pipe.

[0015] As shown in Figure 1, the calculation system 10 is configured to run a program on a general-purpose computer. The calculation system 10 mainly consists of a keyboard 11 that functions as an input means, a memory 12 that stores programs and various data, a CPU (Central Processing Unit) 13 that functions as a calculation means or as a means for temporary storage and comparison of various data, etc., and a display 14 that functions as an output means.

[0016] In the calculation system 10, data for calculating the reduction rate of the manufacturing cost of steel frame structures is entered via the keyboard 11. However, the input means for the calculation system 10 is not limited to the keyboard 11; any known means that can input data for calculating the reduction rate of the manufacturing cost of steel frame structures into the calculation means may be used as appropriate. For example, the input means for the calculation system 10 may consist of a mouse, touch panel, microphone, etc.

[0017] The data entered via keyboard 11 specifically includes weight data for cold-formed steel pipes that constitute steel pipe columns, material unit price data for cold-formed steel pipes, processing cost data for cold-formed steel pipes to be processed into steel pipe columns, weight data for hot-formed steel pipes that can be used as steel pipe columns instead of cold-formed steel pipes, material unit price data for hot-formed steel pipes, processing cost data for hot-formed steel pipes to be processed into steel pipe columns, weight data for beam materials that constitute beams, and material unit price data for beam materials.

[0018] "Weight data of cold-formed steel pipes constituting steel pipe columns" refers to the total weight of cold-formed steel pipes used in all steel pipe columns of a steel frame structure, assuming all steel pipe columns are constructed from cold-formed steel pipes. This data also includes the weight of small amounts of steel plates, such as through diaphragms. "Material unit price data for cold-formed steel pipes" refers to the cost per unit weight of cold-formed steel pipes. "Processing cost data for cold-formed steel pipes to be processed into steel pipe columns" refers to the cost per unit weight of processing cold-formed steel pipes into steel pipe columns. This processing cost data includes welding costs, machining costs, transportation costs, etc.

[0019] "Weight data for hot-formed steel pipes that can be used as steel pipe columns instead of cold-formed steel pipes" refers to the total weight of hot-formed steel pipes used in all steel pipe columns of a steel frame structure when all steel pipe columns are made of hot-formed steel pipes. The weight data for hot-formed steel pipes also includes the weight of some steel plates such as through diaphragms. Here, "hot-formed steel pipes that can be used as steel pipe columns instead of cold-formed steel pipes" refers to hot-formed steel pipes that can be used to manufacture steel pipe columns with performance equivalent to that of cold-formed steel pipe columns when the steel pipe columns are made of cold-formed steel pipes. In other words, it refers to hot-formed steel pipes that are compatible with cold-formed steel pipes when manufacturing steel pipe columns that can be used as substitutes for cold-formed steel pipe columns. Hot-formed steel pipes compatible with cold-formed steel pipes are selected based on their yield point or proof strength, and those with a yield point or proof strength close to that of the target cold-formed steel pipe are selected.

[0020] "Material unit price data for hot-formed steel pipes" refers to the cost per unit weight of hot-formed steel pipes. "Processing cost data for hot-formed steel pipes to be processed into steel pipe columns" refers to the cost per unit weight of processing hot-formed steel pipes into steel pipe columns. The processing cost data for hot-formed steel pipes includes welding costs, machining costs, transportation costs, etc.

[0021] "The weight data of the beam members constituting the beam" refers to the total weight of the beam members used in all the beams of the steel structure. The weight data of the beam members constituting the beam includes the weight of the beam members constituting the main beams, the weight of the beam members constituting the secondary beams, and the weight of some steel plates. "The unit price data of the beam members" refers to the cost per unit weight of the beam members.

[0022] The memory 12 is a flash memory, or a RAM (Random Access Memory), etc., and stores programs (such as programs for calculating the reduction rate of the manufacturing cost of the steel structure) executed by the CPU 13 and data generated by the execution of the programs by the CPU 13.

[0023] The CPU 13 calculates the reduction rate of the manufacturing cost of the steel structure based on the programs stored in the memory 12 and the data for calculating the reduction rate of the manufacturing cost of the steel structure input by the keyboard 11. In the CPU 13, based on the following formula (1), the reduction rate Rcut of the manufacturing cost of the steel structure when using a hot-formed steel pipe instead of a cold-formed steel pipe as the steel pipe column is calculated.

[0024]

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[0025]

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[0026] As shown in equation (1), the reduction rate Rcut for the manufacturing cost of a steel frame structure is given as a function of the weight reduction rate of the steel pipe column. Here, the weight reduction rate of the steel pipe column is the weight reduction rate of the steel pipe column when hot-formed steel pipes are used instead of cold-formed steel pipes. The CPU 13 calculates the "weight reduction rate of the steel pipe column" based on the weight data of cold-formed steel pipes and hot-formed steel pipes entered by the keyboard 11. The CPU 13 calculates the ratio of "the weight of the steel pipe column reduced by using hot-formed steel pipes" to "the total weight of cold-formed steel pipes when the steel pipe column is constructed using cold-formed steel pipes" as the "weight reduction rate of the steel pipe column". Here, "the weight of a cold-formed steel pipe column reduced by using hot-formed steel pipes for the steel pipe column" refers to the difference between "the total weight of cold-formed steel pipes when the steel pipe column is constructed using cold-formed steel pipes" and "the total weight of hot-formed steel pipes when the steel pipe column is constructed using hot-formed steel pipes compatible with cold-formed steel pipes."

[0027] When the CPU 13 calculates the reduction rate Rcut for the manufacturing cost of steel frame structures, it calculates the coefficients ξ and ζ shown in equations (2) and (3) by using the "material unit price data for cold-formed steel pipes" and "material unit price data for hot-formed steel pipes" entered via the keyboard 11 to calculate the ratio of the "material cost of hot-formed steel pipe columns" to the "material cost of cold-formed steel pipe columns". Here, the "material cost of cold-formed steel pipe columns" is the cost per unit weight of cold-formed steel pipes. The "material cost of hot-formed steel pipe columns" is the cost per unit weight of hot-formed steel pipes that are compatible with cold-formed steel pipes.

[0028] When calculating the reduction rate Rcut for the manufacturing cost of steel frame structures, CPU 13 calculates the coefficients ξ and ζ shown in equations (2) and (3) based on the "material unit price data for cold-formed steel pipes" and "processing cost data for cold-formed steel pipes" entered by keyboard 11. This CPU 13 calculates the ratio of "processing cost of cold-formed steel pipes into steel pipe columns" to "material cost of cold-formed steel pipe columns". Here, "material cost of cold-formed steel pipe columns" is the unit price per unit weight of cold-formed steel pipes. "Processing cost of cold-formed steel pipes into steel pipe columns" is the cost per unit weight for processing cold-formed steel pipes into steel pipe columns.

[0029] When calculating the reduction rate Rcut for the manufacturing cost of steel frame structures, CPU13 calculates the coefficients ξ and ζ shown in equations (2) and (3) based on the "material unit price data for cold-formed steel pipes" and "processing cost data for hot-formed steel pipes" entered by keyboard 11. This CPU13 calculates the ratio of "processing cost of hot-formed steel pipes into steel pipe columns" to "material cost of cold-formed steel pipe columns". Here, "material cost of cold-formed steel pipe columns" is the cost per unit weight of cold-formed steel pipes. "Processing cost of hot-formed steel pipes into steel pipe columns" is the cost per unit weight of processing hot-formed steel pipes compatible with cold-formed steel pipes into steel pipe columns.

[0030] When calculating the reduction rate Rcut for the manufacturing cost of steel frame structures, CPU13 calculates the coefficients ξ and ζ shown in equations (2) and (3) by calculating the ratio of the material cost of beams to the material cost of cold-formed steel pipe columns, based on the "material cost data for cold-formed steel pipes" and "material cost data for beams" entered via keyboard 11. Here, the "material cost for cold-formed steel pipe columns" is the cost per unit weight of cold-formed steel pipes. The "material cost of beams" is the cost per unit weight of beams. CPU13 calculates the "material cost of beams" by weighted average, taking into account the weight composition ratio of main beams and secondary beams in the steel frame structure.

[0031] When the CPU 13 calculates the reduction rate Rcut for the manufacturing cost of the steel frame structure, it calculates the coefficients ξ and ζ shown in equations (2) and (3) by calculating the ratio of the "weight of beams" to the "weight of cold-formed steel pipe columns" based on the "weight data of cold-formed steel pipes" and "weight data of beam materials" entered by the keyboard 11. Here, the "weight of cold-formed steel pipe columns" is the total weight of the cold-formed steel pipes used in the steel pipe columns of the steel frame structure. The "weight of beams" is the total weight of the beam materials used in the beams of the steel frame structure.

[0032] As described above, CPU13 calculates the reduction rate in the manufacturing cost of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes by calculating the "weight reduction rate of steel pipe columns", the "ratio of the material cost of hot-formed steel pipe columns to the material cost of cold-formed steel pipe columns", the "ratio of the processing cost of cold-formed steel pipes to the material cost of cold-formed steel pipe columns", the "ratio of the processing cost of hot-formed steel pipes to the material cost of cold-formed steel pipe columns", the "ratio of the material cost of beams to the material cost of cold-formed steel pipe columns", and the "ratio of the weight of beams to the weight of cold-formed steel pipe columns".

[0033] In the calculation system 10, the result of the Rcut reduction rate for the manufacturing cost of the steel frame structure, calculated by the CPU 13, is displayed on the display 14. Based on the Rcut reduction rate for the manufacturing cost of the steel frame structure displayed on the display 14, the user selects either cold-formed steel pipes or hot-formed steel pipes for the column material of the steel pipe column of the steel frame structure.

[0034] Next, we will explain formula (1) for calculating the reduction rate Rcut of the manufacturing cost of steel frame structures. Formula (1) quantifies how much the manufacturing cost of steel frame structures can be reduced by using high-performance hot-formed steel pipes for the steel pipe columns of steel frame structures, using formula (4), which is used to calculate the manufacturing cost of steel frame structures, as shown below. In formula (4), the first term represents the material cost of the steel pipe columns, the second term represents the material cost of the beams, and the third term represents the steel frame processing cost (welding work cost, machining cost, transportation cost, etc.).

[0035]

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[0036] Here, referring to equation (4), the manufacturing cost of a steel frame structure when cold-formed steel pipes are used for the steel pipe columns is given by the following equation (5). Also, the manufacturing cost of a steel frame structure when hot-formed steel pipes are used for the steel pipe columns is given by the following equation (6). Note that in equations (5) and (6), when cold-formed steel pipes are used for the steel pipe columns, the symbol "BC" is shown in the upper quarter portion of each symbol. Also, when hot-formed steel pipes are used for the steel pipe columns, the symbol "SHC" is shown in the upper quarter portion of each symbol.

[0037]

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[0038]

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[0039] Furthermore, from equations (5) and (6), the reduction rate Rcut of the manufacturing cost of a steel frame structure when compatible hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes is given by the following equation (7).

[0040]

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[0041] Furthermore, α and β in equation (7) are given by equations (8) through (11). Here, βc in equation (9) is the contribution of the material cost of steel pipe columns to the reduction rate Rcut of the manufacturing cost of steel structures. βb in equation (10) is the contribution of the material cost of beams to the reduction rate Rcut of the manufacturing cost of steel structures. βf in equation (11) is the contribution of the steel fabrication cost to the reduction rate Rcut of the manufacturing cost of steel structures.

[0042]

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[0043]

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[0044]

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[0045]

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[0046] Furthermore, whether the steel frame structure uses cold-formed steel pipes for the steel pipe columns or hot-formed steel pipes for the steel pipe columns, the weight of the beams is approximately the same, and this trend is independent of the seismic calculation route, collapse type, and intended use of the steel frame structure. Moreover, the weight and steel type of the secondary beams are basically independent of the steel type of the steel pipe columns. Therefore, in calculating the reduction rate Rcut for the manufacturing cost of the steel frame structure using equation (7), it can be assumed that the following equations (12) and (13) hold true.

[0047]

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[0048]

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[0049] Furthermore, within the steel frame fabrication costs, machining costs and transportation costs do not depend on the type of steel used for the steel pipe columns. Also, since cold-formed steel pipe columns require stricter welding control than hot-formed steel pipe columns, the welding costs for steel frame structures using cold-formed steel pipes are expected to be higher than those for steel frame structures using hot-formed steel pipes. However, since it is difficult to quantify the costs associated with welding control, in calculating the reduction rate Rcut for the fabrication costs of steel frame structures using equation (7), we assume that the following equation (14) holds true.

[0050]

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[0051] In the reduction rate Rcut for the manufacturing cost of steel structures given by equation (7), the coefficient βb, which represents the contribution of the beam material cost given by equation (10), becomes zero in the parentheses on the right side from equations (12) and (13), resulting in βb = 0 as shown in equation (15).

[0052]

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[0053] Furthermore, in the reduction rate Rcut for the manufacturing cost of steel structures given by equation (7), the coefficient βf, which represents the contribution of steel fabrication costs given by equation (11), is simplified as shown in equation (16) by making the second and third terms in parentheses on the right-hand side zero, according to equations (12) to (14).

[0054]

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[0055] As a result, the reduction rate Rcut, which represents the reduction in manufacturing costs of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes, is given as a function of the weight reduction rate of the steel pipe columns, as shown in equation (1).

[0056] As described above, the calculation system 10 of the present invention makes it easy to confirm the reduction rate in manufacturing costs of a steel frame structure when hot-formed steel pipes are used as steel pipe columns instead of cold-formed steel pipes. [Explanation of Symbols]

[0057] 10 Calculation System

Claims

[Claim 1] A calculation system for calculating the reduction rate of manufacturing costs in a steel frame structure constructed by connecting steel pipe columns and beams to the beam connection parts of the steel pipe columns, An input means for inputting the weight data of the cold-formed steel pipes constituting the steel pipe column, the material unit price data of the cold-formed steel pipes, the processing cost data of the cold-formed steel pipes for processing the cold-formed steel pipes into the steel pipe column, the weight data of hot-formed steel pipes that can be used as the steel pipe column instead of the cold-formed steel pipes, the material unit price data of the hot-formed steel pipes, the processing cost data of the hot-formed steel pipes for processing the hot-formed steel pipes into the steel pipe column, the weight data of the beam material constituting the beam, and the material unit price data of the beam material. The system includes a calculation means for calculating the reduction rate of manufacturing costs for the steel frame structure based on the data input by the input means, The calculation means is Based on the weight data of the cold-formed steel pipe and the weight data of the hot-formed steel pipe input by the input means, the weight reduction rate of the steel pipe column when the hot-formed steel pipe is used instead of the cold-formed steel pipe is calculated. Based on the material cost data for the cold-formed steel pipe and the material cost data for the hot-formed steel pipe input by the input means, the ratio of the material cost of the hot-formed steel pipe column to the material cost of the cold-formed steel pipe column is calculated. Based on the material cost data and processing cost data of the cold-formed steel pipe input by the input means, the ratio of the processing cost of the cold-formed steel pipe into a steel pipe column to the material cost of the cold-formed steel pipe column is calculated. Based on the material cost data for the cold-formed steel pipe and the processing cost data for the hot-formed steel pipe input by the input means, the ratio of the processing cost of the hot-formed steel pipe to the material cost of the cold-formed steel pipe to the steel pipe column is calculated. Based on the material cost data for the cold-formed steel pipe and the material cost data for the beam material input by the input means, the ratio of the material cost of the beam to the material cost of the cold-formed steel pipe column is calculated. Based on the weight data of the cold-formed steel pipe and the weight data of the beam material input by the input means, the ratio of the weight of the beam to the weight of the steel pipe column of the cold-formed steel pipe is calculated. Based on the weight reduction rate of the steel pipe columns, the ratio of the material cost of the hot-formed steel pipe columns to the material cost of the cold-formed steel pipe columns, the ratio of the processing cost of the cold-formed steel pipes into steel pipe columns to the material cost of the cold-formed steel pipe columns, the ratio of the processing cost of the hot-formed steel pipes into steel pipe columns to the material cost of the cold-formed steel pipe columns, the ratio of the material cost of the beams to the material cost of the cold-formed steel pipe columns, and the ratio of the weight of the beams to the weight of the cold-formed steel pipe columns, the reduction rate of the manufacturing cost of the steel frame structure when the hot-formed steel pipes are used as the steel pipe columns instead of the cold-formed steel pipes. A calculation system characterized by the following.

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