Analysis of Quality Problems in Steel Structure Engineering
Steel structure quality is difficult to guarantee the reasons there are many, and very complex, both the problems caused by improper process, Steel Structure but also violations of the operation caused by the problem, as well as the technical level of the construction staff and the responsibility caused by the problem, as well as decision makers Mistakes caused by quality problems.
The problem of steel itself
A unit in the processing of a building 1200 * 1200 * 60 box-shaped column, in the welding process suddenly found 60mm as a thick plate of the wall appeared tearing phenomenon, the visible visible cracks from the thickness direction of the board is divided into two halves , After NDT detection found that the depth of the crack occurred in the depth of about 3mm, Steel Structure while the same type of the same batch of several pieces of the board cutting parts of the detection and found that the existence of sandwich board, rolling quality is the main cause of quality problems. The material of the interlayer is pulled away during the welding process due to the welding stress generated by welding. Resulting in a thick plate along the thickness of the phenomenon of tearing.
Cause Analysis: Due to the special nature of the use of parts, the parts used in the component as a web, the vertical and vertical welding parts in the welding form of the full penetration of the groove through the strength of the plate, due to the existence of the plate , The welding stress generated by welding is released outward to tear the plate in the thickness direction.
Can be based on the actual situation to take the following measures to deal with:
(1) a large number of steel within the sandwich belongs to the steel itself in the rolling process of quality problems, has exceeded the requirements of the national standard specifications, you can ask the steel factory sent to verify, with the steel factory to return or replacement deal with;
(2) If the number of interlayers is small, the technical department and the owner can be consulted, and the information is fed back to the steel mill. Steel Structure The construction remedial measures can be taken. According to the result of the nondestructive testing, all the planers Open, more than their own depth, and then use the same strength welding material to fill, after the completion of the surface treatment, after the specified time in the NDT detection, while the same component sampling physical and chemical testing to meet the design requirements can continue to use;
(3) cut off the parts under the supervision of the supervision, Steel Structure re-replaced the conditions to meet the conditions of the plate, replaced parts for non-load and non-important parts or as auxiliary materials used, after the completion of the specified time after the NDT detection, good record.