The decisive factor in selecting the thickness of the floor bearing plate is the spacing between the steel beams under the floor bearing plate. The distance between steel beams of open floor bearing plates is generally no more than 3m, and the main frame span of many steel structures is 5-6m or more. At this time, the secondary beam needs to be added. Angle steel, channel steel, C-steel or support under the floor bearing plate can be used, that is, the condition that the beam distance is no more than 3m needs to be met anyway.
For some small buildings, such as private residential areas and steel structure office buildings, the distance between steel beams is generally only 1-2m, or even less than 1m. At this time, 0.8mm floor bearing plate can be used. For ordinary steel structure workshop, the distance between steel beams is generally 2-3m, 1.0mm floor bearing plate can be used for 2-2.5m, and 1.2mm floor bearing plate can be used for more than 2.5m. Generally, these thicknesses can meet the requirements of ordinary steel structure construction. Of course, we advocate to refer to the unsupported span table of floor bearing plate in National Atlas and select a good one.
The closed floor bearing plate is processed in the factory in strict accordance with the planned planking drawing, the plate arrangement sequence has been numbered, and the open floor bearing plate. There is no need to cut the supplementary plate for on-site construction, which is convenient for on-site installation of steel structure; When arranging the bearing plate of the closed building, it only needs to be arranged in sequence according to the span. When connecting with the steel beam, due to the flat bottom of the plate, it can meet the requirements of the actual connection area with the steel beam. Therefore, it can be directly paved without treatment (the opening plate needs to be cut and repaired to avoid virtual overlap with the steel beam).
The bearing plate of open floor slab shall be sealed at the end to avoid slurry leakage from the opening at the bottom of the slab, while the bearing plate of closed floor slab does not need to be blocked by the end plate due to the closure of the web. Because the bottom of the closed floor bearing plate is flat, it can be fully combined with the upper wing plate of the steel beam regardless of whether it is horizontally or smoothly overlapped with the steel beam. Therefore, the top surface of the upper wing plate of the steel beam does not need to be sprayed with fireproof paint. There is a hole between the open floor bearing plate and the steel beam, and the shoulder plug gap needs to be made.