Bài 8, cũng là bài cuối của loạt bài về kết cấu của Bảo tàng Edo Tokyo

This image displays a page from a 1994 technical journal titled "Steel Construction Engineering" concerning welding techniques for structural steel.

• It details the use of two-electrode automatic electroslag welding for 80mm thick TMCP (Thermo-Mechanically Controlled Processing) steel.

• The article includes technical tables regarding welding conditions and mechanical test results such as tensile, impact, and hardness tests.

• The document concludes by emphasizing that the construction method met all mechanical properties and building standards without issue.

Translation

• Steel Construction Engineering Vol. 1 No. 1 (March. 1994)

• After removing the end tabs, the flange groove was shaped with a grinder, and after adjusting the groove, a penetrant inspection confirmed that there were no gouging residues or defects inside the groove, and the work was completed.

• Table 3 Welding Conditions

• Voltage (V)

• Figure 13 Welding part Vickers hardness test results

• Table 4 Test Results

• Photo 9 Automatic electroslag welding

• 6.4 Mechanical Testing

• Although TMCP steel has a lower carbon equivalent and better weldability compared to conventional SM430A, etc., this project uses two-electrode automatic electroslag welding, which is a high heat input welding method, on 80mm thick material. Therefore, strength, impact characteristics, and hardness tests were performed on the welded joint area to confirm that the mechanical properties satisfied those at the time of TMCP material minister certification acquisition.

• The test specimen was BH-500X500X50X50 (TMCP F-3.3t/㎡), and an electroslag welding test was performed under the same conditions as on-site construction.

• The test items are ultrasonic flaw detection test, tensile test, impact test (test temperature 0 degrees), bending test, macro test, and hardness test. The test results are shown in Figure 13 and Table 4. All test results satisfied the base material standard values, and it was confirmed that the bending test results showed no cracks and had good bending ductility. In addition, no defects were observed in the macro test, and it was confirmed that the fusion into the base material was sufficient. In the hardness test results, the maximum hardness was HV203 and the minimum hardness was HV141, and no particular abnormalities were observed.

• 7 Conclusion

• Due to the peculiarity of its shape, this building became a large-scale steel structure, and the weight of a single piece became large. Therefore, the design proceeded while paying attention to the workability and construction method of on-site welding from the design stage. Also, regarding construction, the construction method was examined during the planning stage, and the most rational construction method was adopted. As a result, the construction proceeded without any particular problems.

• In conclusion, I would like to express my sincere gratitude to everyone involved who guided us from the planning of this construction to the completion.

• References

• (1) Kojima Kenji, Miyamura Masamitsu, Kanda Tomohiro, Tsuji Shinichi, Suzuki Kazuo et al., Development of Large-scale Vertical Movement System (Part 1), Architectural Institute of Japan Academic Lecture (November 7, 1983)

• -94-

AI responses may include mistakes.