怎样让屋面彩钢板和楼承彩钢板做到更薄
许多建筑师希望在大悬挑或大跨度的情况下,屋面彩钢板和楼承彩钢板可以薄、薄、超薄。但这对结构工程师来说是一个巨大的挑战。由于板的刚度与截面高度的三次方成正比,屋面彩钢板和楼承彩钢板如果板的厚度减小一点,刚度就会大幅度降低。如何解决这个问题?我们慢慢来吧。
以混凝土结构为例,首先,混凝土板需要在现场进行湿作业,延长了施工周期;其次,由于自身的重要性,导致混凝土板跨度较小,并且严格控制板下开间的尺寸。主次梁和附加建筑表层的传力方式降低了建筑楼层的净高(如图1所示),极大地限制了建筑创作的范围,不利于新颖独特的建筑诞生。
以钢结构为例,网架结构是一种优良的双向传力空间结构体系,常用于大型悬臂结构中。但是,对于1250的厚度,完工表面需要2050。加厚2050-1250=800mm为檩条托架、檩条和龙骨龙骨的附加厚度。建筑师希望,当结构厚度较薄时,网格结构显得无能为力。
板桁架是一种轻型超薄空间传力板体系,具有足够的强度和刚度,可以进行多向悬臂施工,不需要湿作业,生产和施工速度快。两侧钢板既是受力结构,又是围护结构。与现有技术相比,板桁架的有益效果是:工厂加工生产,现场拼装,全过程无湿作业,大大缩短了工期;取消了主次梁,厚度小,自重轻,无需建筑面层,增加了建筑的净高;轴向力、空间力的传递,提高了板在各个方向的强度、刚度和跨度,有利于帮助建筑师实现图形化的设计思想。
Many architects hope that in the case of large overhanging or large span, the roof slab and floor slab can be thin, thinner and ultra-thin. But this is a big challenge for structural engineers. Because the stiffness of the plate is directly proportional
to the third power of the height of the section, if the thickness of the plate is reduced a little, the stiffness will decrease a lot. How to solve this problem? Let's take our time.
At present, no matter it is concrete structure or steel structure, the floor slab and load-bearing roof slab are basically cast-in-place concrete slab. Although it can well meet the needs of general buildings, its shortcomings are obvious in some buildings
with high requirements on appearance, practicability and construction period.
Taking the concrete structure as an example, firstly, the concrete slab needs to be wet operated on site, which prolongs the construction period; secondly, it is self important, which results in the small span of the slab, and the size of the bay
under the slab is strictly controlled. The force transfer mode of the main and secondary beams and the additional building surface layer reduce the building net height of the floor (as shown in Figure 1), which greatly limits the scope of building creation
and is not conducive to novel and unique buildings The birth of.
Taking steel structure as an example, grid structure is an excellent two-way force transmission space structure system, which is often used in large cantilever structure. However,
for the thickness of 1250, the finished surface needs 2050. The extra 2050-1250 = 800mm is the added thickness of purlin bracket, purlin and cladding keel. Architects hope that when the thickness of the structure is thin, the grid structure appears powerless.
Plate truss is a kind of light and ultra-thin space force transfer plate system, which has enough strength and stiffness, can carry out multi-directional cantilever, and does not need wet operation, so it has fast production and construction. The
steel plates on both sides act as both the stress-bearing structure and the enclosure structure. Compared with the existing technology, the beneficial effects of the plate truss are as follows: factory processing and production, on-site assembly, no wet
operation in the whole process, greatly shortening the construction period; canceling the primary and secondary beams, with small thickness and self weight, without building surface layer, increasing the clear height of the building; axial force, spatial
force transmission, improving the strength, stiffness and span of the plate in each direction, which is conducive to help architects realize the design idea Figure.