Almost all the warehouses we see now are steel structures, especially newly built warehouses are almost all built with steel structures. The steel structure warehouse has a small building column area, which can reduce the indoor area and increase the available space. It is safe and durable, has good earthquake resistance, short construction period, cost saving, convenient installation and disassembly, and recyclable. These advantages all meet the needs of warehouses very well. Especially in the era of rapid economic development, the replacement is rapid, and efficiency, speed, and speed can better meet economic needs. This is also the main reason why steel structure warehouses replace ordinary concrete warehouses.
The material of steel structure warehouses is mainly structural steel, and reducing the amount of steel is an effective way to reduce costs. So how can optimize the design of steel structure warehouses and reasonably reduce the amount of steel?
Reducing the amount of steel is not cutting corners, but under the condition of maintaining the safety of the building, through reasonable design and optimization design, try to use less steel. The length and width design of the building, the design of the steel column, the span size, the roof slope, the eaves height, the support system layout, etc. will affect the amount of steel used, so a reasonable design can completely reduce the amount of steel used.
Optimization of building length and width design
Generally speaking, when arranging the column grid, the principle of length being greater than width should be followed, which can reduce the amount of steel used in the rigid frame, and at the same time reduce the wind load of the column support, there reducing the amount of steel used in the support system. For example: the warehouse should be 70M long and 50M wide, rather than 70M wide and 50M long.
Optimization of warehouse column spacing design
The most economical column spacing under standard load is 7-9m. When it exceeds 9m, the amount of steel used in the roof purlins and wall beams increases too much, and the comprehensive cost increases. 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 large, the economic column spacing should be reduced accordingly. For workshops with gantry cranes above 10 tons, the economic column spacing should be 6~7m.
Optimization of warehouse span design
When the column height and load are certain, the span is appropriately increased, the increase in the amount of steel used in the rigid frame is not obvious, but it saves space, the basic cost is low, and the comprehensive benefits are considerable.
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 unit steel consumption of the rigid frame between 21-48m is 12-24kg/m2. When the eaves height is 12m and the span exceeds 48m, the multi-span steel frame can save more than 40%, so the design of the steel structure warehouse should choose a more economical span according to specific requirements. It is not advisable to blindly pursue a large span.
Choice of roof slope
The roof slope needs to be determined according to the structure of the roof panel, the length of the roof drainage slope and the height of the column structure, generally 1/10~1/30. Different roof slopes have a great influence on the steel consumption of the steel structure warehouse design. For a single-span steel frame, increasing the roof slope can reduce the deadweight of the rigid frame, so the larger the slope, the more steel consumption is saved. For multi-span frames, large slopes will increase the length of the inner columns, but large slopes will increase the amount of steel used in the frame.
Through research and calculation, the more economical slope is:
- Multi-span buildings: 1:20
- Single span, span less than 45m: 0.5:10
- Single span, span less than 60m: 1.5:10
- Single span, span greater than 60m: 2.0:10
Eaves height selection
Eaves height is determined the following factors:
Net height requirements at the eaves; 2. When there is a mezzanine, the net height requirements of the mezzanine and the height of the mezzanine beam; 3. When there is a crane, the height of the crane beam and the crane hook.
The height of the eaves has a great impact on the cost. The increase in the eaves height will increase the area of the wall panels, the wall purlins will increase, and the amount of steel used in the steel columns will also increase.
Support system layout
The column support should be located on the same span as the roof support. When the door is on the wall and the wall support cannot be installed, the column support can be set on the adjacent span. Generally speaking, the support spacing should not exceed 5 spans. It is suitable to be 30-45 meters when there is no crane, and the spacing is generally not more than 60 meters when there is a crane.
The main purpose of the warehouse is to store goods. The design should mainly consider the needs of goods and process flow, and should follow the principle of simplicity and rationality. Reasonable optimization of design can reduce the amount of steel used and reduce construction costs.
