选择楼板承重板厚度的决定因素主要是楼板承重板下钢梁之间的间隔。开口楼板承重板的钢梁距离一般不超过3米，许多钢结构的主框架跨度为5-6米甚至更大。此时，需要增加二次梁，可以使用角钢、槽钢、C型钢或在楼板承重板下增加支撑，也就是说，无论如何需要满足梁距离大不超过3米的条件。

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，如私人住宅区、钢结构办公楼等，钢梁的距离一般只有1-2米，甚至小于1米，此时可使用0.8mm的楼板承重板。普通钢结构厂房，钢梁的距离一般在2-3米之间，2-2.5米可使用1.0mm的楼板承重板，超过2.5米可使用1.2mm的楼板承重板，一般这几个厚度都能满足普通钢结构施工的要求，当然我们主张参考国家图集楼板承重板无支撑跨度表，选择好的。

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.

闭口楼承板严格按规划铺板图在工厂加工，排板顺序已编号，开口楼板承重板。现场施工不需要切割补板，方便钢结构现场装置；闭口楼承板排板时只需按跨距顺排，与钢梁顺接时，由于板底平整，有满足与钢梁实接面积的要求。所以不用处理就可以直接铺上过去(开口板因为要避免与钢梁虚搭而需要切开补板)。

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).

开口楼板承重板应密封在端口，避免浇筑混凝土从板底开口漏浆，而闭口楼板承重板因腹板闭合而不需要端板堵塞。闭口楼承板由于板底平坦，无论与钢梁横搭还是顺搭，都可以与钢梁上翼板充分结合，因此钢梁上翼板顶面不需喷涂防火涂料。开口楼承板与钢梁之间有空洞，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.