Steel structure roof trusses refer to a single-row structure that bears roof loads. Steel columns and steel roof trusses form…
The raw material of the steel structure warehouse building is steel. Paying attention to the optimization plan in the steel structure warehouse design can reduce the amount of steel used and then effectively reduce the cost.
There are currently more and more steel structure buildings, whether high-rise buildings, aircraft hangars, railway stations, exhibition centers or activity centers, museums, shopping malls, factories, scenic spots, bridges, and steel structure projects, that can be seen everywhere. Modern warehouses are almost always steel structures. The steel structure warehouse building has less column area, can reduce indoor size, increases usable space, has good seismic performance, has a short construction period, and saves money. The advantages are undeniable.
Features of the steel structure warehouse
- Wall and Roof panel: The steel structure warehouse mainly adopts a lightweight enclosure structure, such as a sandwich panel or corrugated metal sheet. The material is lighter and has fire prevention functions, heat insulation, and heat preservation, But it can also bear heavier loads. Moreover, it is easy to install and can effectively replace the previous wall, roof panel, and many consumables.
- Ample internal space: Unlike traditional buildings, the steel structure warehouse has much interior activity space. Therefore, the eave height and column spacing of the steel structure warehouse will be much larger than that of ordinary buildings, making steel structure warehouse buildings have more space.
- The construction period is short, and it is easy to dismantle and reuse:
The former factory structure mainly adopts the form of reinforced concrete. This form is complicated in technology and very difficult to construct. Because the existing steel structure warehouse buildings are integrated with design, fabrication, and construction. The construction period can be effectively shortened, and it is easy to dismantle and reuse and reduce construction costs.
Steel Structure Warehouse Design:
Building length and width
When process the steel structure warehouse design, if the size of the building is 60×50m, 60m should be taken as the length direction and 50m as the wide direction, namely: 60(L)×50(W) instead of 50(L)×60(W).
Column distance of Steel Warehouse
The most economical column distance under the standard load is 7-9m. When it exceeds 9m, the steel consumption of the roof purlin and wall girt will increase too much, and the comprehensive cost will increase. The standard load refers to the roof live load of 0.3KN/m2 and the basic wind pressure of 0.5KN/m2. When the load is greater, the economic column spacing should be reduced accordingly. For a workshop with cranes of more than 10 tons, the economic column distance should be 6~7m.
The Span of Warehouse Building
Through a large number of calculations, it is found that when the eaves height is 6m, the column distance is 7.5m, and the load conditions are the same, the unit steel consumption (Q355B) of the steel frame with a span between 18-30m is 10-15kg/m2. The amount of steel used for the rigid frame unit between 21-48m is 12-24kg/m2. When the eaves height is 12m, and the span exceeds 48m, a multi-span steel frame can save more than 40%, so steel structure warehouse design should choose a more economical span according to the specific requirements. It is not advisable to blindly pursue a large span.
Roof slope in Steel Structure Warehouse Design
The slope of the roof needs to be determined according to the structure of the roof panel, and the length of the roof drainage slope and the height of the column structure, etc. It is generally 1/10~1/30. Different roof slopes have a greater impact on the amount of steel used in the steel structure warehouse design. For a single-span steel frame, increasing the roof slope can reduce the weight of the rigid frame, so the greater the slope, the more saving the amount of steel used. For a multi-span frame, a large slope will increase the length of the inner column, but a large slope will increase the amount of steel used in the frame.
These factors determine the height of the eave:
1)The clear height requirement at the cornice; 2)When there is a mezzanine, the clear height requirement of the mezzanine and the height of the floor beam; 3)When there is a crane, the height of the crane beam and the crane hook.
The height of the cornice has a great influence on the cost. The increase in the height of the eave will increase the area of the wall panel, the wall purlin will increase, and the steel consumption of the column will also increase.
The layout of the bracing System
The column bracing should be located on the same span as the roof bracing. When the wall bracing cannot be installed due to the door on the wall, the column bracing can be set on the adjacent span. Generally speaking, bracing spacing should generally not exceed five spans; when there is no crane, it should be 30~45m, and when there is a crane, the spacing should generally not be greater than 60m.
Details that cannot be ignored in steel structure warehouse design
This is an essential requirement for buildings. To achieve the anti-seepage effect, it is necessary to use sealing washers at the screw openings and then fix them in a concealed manner. Use sealant or welding at the overlap of the color steel plates, if possible. Use full-body panels to minimize overlap and perform strict waterproofing at various joints. And it should be highlighted in the steel structure design drawings.
Wind pressure resistance:
The windproof performance of the warehouse building is related to the fastening force and density of the fixed base. The designer must ensure that the metal roof panels will not be pulled off by negative wind pressure.
Sound insulation may be one of many people’s concerns about steel structure buildings, but filling the wall layers with sturdy insulation materials can solve this problem. Of course, the sound insulation effect is related to the density and thickness of the sound insulation material, which can be selected as needed.
Vents should be installed on the roof to ensure indoor and outdoor air exchange.
Water vapor usually condenses on the bottom and inner layers of the roof, so the water vapor in the top must be drained away. The solution is to fill the wall layer with thermal insulation cotton, lay a waterproof membrane on the floor, and design ventilated nodes on the panel.
At the beginning of the design, the steel structure warehouse must consider the construction load, rainwater, snow pressure, and maintenance load. Therefore, the load-bearing capacity of the panel, plate cross-section, strength and thickness of the material, force transmission method, and purlin spacing must be considered.
No matter how high the building is, we must also consider preventing lightning from entering the room through the metal roof, especially metal-based steel buildings.
The thermal insulation performance of steel structure factory buildings is closely related to the raw materials, density, and thickness of the insulation cotton. At the same time, the “cold bridge” phenomenon must be prevented.
When designing, it is necessary to consider arranging lighting panels or glass at specific locations. The service life of the skylight must be coordinated with the metal roof panel, and waterproofing should be done at the connection between the skylight and the metal panel.