選擇樓板承重板厚度的決定因素主要是樓板承重板下鋼梁之間的間隔。開口樓板承重板的鋼梁距離一般不超過3米，許多鋼結構的主框架跨度為5-6米甚至更大。此時，需要增加二次梁，可以使用角鋼、槽鋼、C型鋼或在樓板承重板下增加支撐，也就是說，無論如何需要滿足梁距離大不超過3米的條件。

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.

有些小建筑，如私人住宅區、鋼結構辦公樓等，鋼梁的距離一般只有1-2米，甚至小于1米，此時可使用0.8mm的樓板承重板。普通鋼結構廠房，鋼梁的距離一般在2-3米之間，2-2.5米可使用1.0mm的樓板承重板，超過2.5米可使用1.2mm的樓板承重板，一般這幾個厚度大多能滿足普通鋼結構施工的要求，當然我們主張參考國家圖集樓板承重板無支撐跨度表，選擇好的。

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.

閉口樓承板嚴格按規劃鋪板圖在工廠加工，排板順序已編號，開口樓板承重板。現場施工不需要切割補板，方便鋼結構現場裝置；閉口樓承板排板時只需按跨距順排，與鋼梁順接時，由于板底平整，有滿足與鋼梁實接面積的要求。所以不用處理就可以直接鋪上過去(開口板因為要避免與鋼梁虛搭而需要切開補板)。

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).

開口樓板承重板應密封在端口，避免澆筑混凝土從板底開口漏漿，而閉口樓板承重板因腹板閉合而不需要端板堵塞。閉口樓承板由于板底平坦，無論與鋼梁橫搭還是順搭，都可以與鋼梁上翼板充分結合，因此鋼梁上翼板頂面不需噴涂防火涂料。開口樓承板與鋼梁之間有空洞，需做肩塞空隙。

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.