Common problems in steel structure engineering construction

Common problems and measures in the construction of steel structure engineering

1. Production and production of components

The plate used for the portal steel frame is very thin, and it can be as thin as 4 mm. For the blanking of multi-thin sheets, the cutting method should be selected and flame cutting should be avoided. Because cutting with flame will cause great wave deformation on the edge of the board. At present, most manufacturers of H-beam welding use submerged arc automatic welding or semi-automatic welding. If the control is not good, welding deformation should occur, so that the components are bent or twisted.

2. Column foot installation problem

①Problems with embedded parts (anchor bolts): overall or layout deviation, wrong elevation,no protection measures for the thread. It directly causes the bolt holes of the steel column bottom plate to be out of position, resulting in insufficient thread length.

Measures: The steel structure construction unit cooperates with the civil construction unit to complete the pre-embedded parts work. Before the concrete is poured, it is necessary to review the relevant dimensions and fix it firmly.

②The phenomenon of anchor bolts not being vertical: the level of the bottom plate of the frame column and column foot is poor, the anchor bolts are not vertical, and the horizontal error of the pre-embedded anchor bolts after foundation construction is too large. After the column is installed, it is not in a straight line, and it is crooked, which makes the appearance of the house unsightly, brings errors to the installation of the steel column, affects the structural force, and does not meet the requirements of the construction acceptance specification.

Measures: The anchor bolt installation should insist on first leveling the bottom plate with the lower adjusting bolt, and then filling it with non-shrinkage mortar secondary grouting. Therefore, during the construction of anchor bolts, steel bars or angle steel can be used to fix the anchor bolts. Weld into a cage shape, improve the support, or take some other effective measures to prevent the anchor bolt from shifting one position when pouring the foundation concrete.

③The phenomenon of anchor bolt connection: the column foot anchor bolt is not tightened, the backing plate is not welded with the bottom plate; some anchor bolts with 2 to 3 threads are not exposed.

Measures: Welding bolts and nuts should be adopted; on the outside of chemical anchors, fire-retardant coatings and heat insulation treatment should be thickened to prevent the anchoring performance from being affected in case of fire; the observation data of foundation settlement should be supplemented.