Due to its own advantages, it is widely used in modern buildings such as bridges, industrial plants, and high -rise buildings. In the process of a large number of engineering construction, many quality problems have also been exposed. Today we mainly analyze the problems and solutions encountered in the middle:
1. Production problems
The plates used in the door -type steel frame are very thin. Essence The cutting method of the thin plate should be cut to avoid cutting with flames. Because the use of flame cutting will cause a large wavy to deformed. At present, most manufacturers of H -shaped steel welded were automatically welded or semi -automatic welding. If the control is not well controlled, welding deformation occurs, and the component is bent or distorted.
2. Installation of steel structure column feet
(1) Phenomenon of embedded parts (anchor bolt): overall or layout offset; error of the elevation; no protection measures for wire buckles. Directly cause the steel column bottom plate bolt holes to be incorrect, resulting in insufficient length of the wire buckle.
Measures: The steel structure construction unit cooperates with the civil construction unit to complete the embedded parts work, before the concrete is poured. Related sizes and fixed firmness must be reviewed.
(2) The anchor bolt is not vertical: The horizontal level of the soles of the foot pillar is poor, the anchor bolt is not vertical, and the horizontal error of the embedded anchor bolt after infrastructure is too large. The column is not on a straight line after installation, and it is crooked in the east, making the appearance of the house unsightly. It brings errors to the steel column installation.
Measures: The anchor bolt installation should insist that the bottom plate should be adjusted with the lower part with the lower part, and then the secondary grouting of the contracted mortar is filled with the secondary grouting. Therefore, when the anchor embolism is constructed, a fixed anchor bolt can be used with steel bars or corner steel. Welded into a cage, improved support, or took other effective measures to avoid the anchor embolism when pouring the basic concrete.
(3) The phenomenon of anchor embolism connection: The pillar foot anchor bolt is not tightened, the pad is not welded with the bottom plate; part of the anchor bolt of 2 to 3 filaments is not exposed.
Measures: Welding anchor rods and nuts should be adopted; outside the chemical anchor embolism, thick fireproof coatings should be treated to prevent the anchor performance from being lost when losing fire;
3. The problem of steel structure connection
(1) High -strength bolt connection
1) The bolt equipment does not meet the requirements, causing the bolts to be installed, or bolts, or bolts The degree of tightness does not meet the design requirements.
Analysis of the cause:
① The surface has impurities such as rust, oil pollution, and bolt holes and welding tumors.
② The installation surface of the bolt is still defective although it has been treated.
Solution:
① The problem of rust, oil pollution, and bolt holes on the surface of high -strength bolts should be cleaned one by one. Before use, it must be processed by rust to make the assembly bolt, not The-Application-OF-the-Portable-WHOLE-I -INSTALLEON-OF-STRUCTURE-OF-The Drill-And-Mining-Manager may be used in formal assembly. The bolts should be kept and distributed by special personnel.
② Treatment of the preparation surface should be taken into account the order and installation order to prevent repeated progress and try to deal with it before hanging.
2) Bolt filament damage, the screw cannot spin the nut freely, affecting the assembly of the bolt.
Analysis of the cause: The wire buckle is severely rust.
Solution:
① Use the bolt before using the bolt should be selected. After cleaning the rust and removing, pre -mixing.
② The bolt of the silk buckle damage cannot be used for temporary bolts, and it is strictly forced to enter the threaded hole.
③ The pre -selected bolt component should be stored according to the set, and it must not be changed when used.
(2) On -site weld phenomenon: quality is difficult to guarantee; design requires the first or second -level welding seams that require full welding. Welding.
Solution: Before the steel structure is welded, check the qualification certificate of the strip, and select the welding bars according to the design requirements. One or second -level welding seams must not have air holes, slag, and arc pits cracks. The first -class welds must not have defects such as bite and unpleasant welding. The part of the welder should be checked. Unqualified welds shall not be processed without authorization. After the modification process is set, it should be processed. The number of welds in the same part should not exceed twice.