Seismic design of single-span double-slope steel structure warehouse
In modern industrial buildings, single-span double-slope steel structure warehouses are widely used due to their high space utilization and fast construction speed. However, in areas where earthquakes occur frequently, it is crucial to ensure the seismic performance of such warehouses. The following will elaborate on the seismic design points of single-span double-slope steel structure warehouse.
1. Structural selection and layout
Reasonable structural selection and layout are the basis of seismic design. The structural form of a single-span double-slope steel structure warehouse should be determined comprehensively based on factors such as the warehouse’s use function, span, height, and geological conditions. In terms of structural layout, the mass and stiffness of the structure should be distributed evenly as much as possible to avoid torsion effects. At the same time, the layout of the column grid should be regular and neat to reduce stress concentration under earthquake action.
For example, a portal frame structure can be used, which has good spatial force performance and economy. When arranging the portal frame, the spacing of the frame should be reasonable to avoid insufficient lateral stiffness of the structure due to excessive spacing. In addition, the setting of the support system is also crucial. Reasonable arrangement of column supports and roof supports can effectively improve the overall stability and seismic resistance of the structure.
2. Calculation of earthquake action
Accurate calculation of earthquake action is a key link in earthquake-resistant design. When calculating earthquake action, the appropriate earthquake action calculation method should be selected according to the seismic fortification intensity, site category, structural natural vibration period and other factors in the area where the building is located, in accordance with relevant specifications.
In general, for single-span double-slope steel structure warehouses, the bottom shear method can be used for preliminary estimation. However, for warehouses with more complex structures or higher heights, the vibration mode decomposition response spectrum method or time history analysis method is required for accurate calculation. In the calculation process, the influence of factors such as the damping ratio and mass distribution of the structure on the seismic action should be fully considered.
3. Component design and connection
Component design
Steel beam: The steel beam should have sufficient strength, stiffness and stability. When designing, the cross-sectional size and material of the steel beam should be reasonably determined based on the calculation results of the internal force under the action of the earthquake. At the same time, the plastic deformation capacity of the steel beam under the repeated action of the earthquake should be considered to avoid brittle failure of the steel beam.
Steel column: As the main vertical load-bearing member, the seismic performance of the steel column directly affects the safety of the entire structure. The design of the steel column should meet the axial compression ratio limit requirements to ensure that the steel column has good ductility under earthquake action. In addition, the connection between the steel column and the foundation should be strengthened to ensure that the steel column can reliably transmit the seismic force.
Connection design
Beam-column connection: The beam-column connection node is a key part to ensure the integrity of the structure. In seismic design, the beam-column connection should adopt a rigid connection, such as a welded connection or a high-strength bolt connection. The design of the connection node should meet the principle of “strong node, weak component” to ensure that the node does not fail before the component under earthquake action.
Support connection: The connection between the support and the beam column should also have sufficient strength and reliability. The support connection node should be able to effectively transmit the support force to avoid the destruction of the connection node under earthquake action, resulting in support failure.
4. Foundation design
The foundation is an important component that transmits the seismic force of the superstructure to the foundation. When designing the foundation, it is necessary to reasonably select the foundation form, such as independent foundation, raft foundation, etc., according to the geological survey report. The buried depth of the foundation should meet the requirements of the specification to ensure the stability of the foundation.
At the same time, the anti-slip and anti-overturning capabilities of the foundation under earthquake action should be considered. The seismic performance of the foundation can be improved by increasing the bottom surface area of the foundation and setting anti-slip keys.
5. Design of non-structural components
Non-structural components in the warehouse, such as enclosure structures, hanging equipment, etc., may also affect the safety of the structure under earthquake action. Therefore, in the seismic design, non-structural components should be reasonably designed and connected.
For example, the enclosure structure should be reliably connected to the main structure to avoid falling off and injuring people under earthquake action. The bracket of the hanging equipment should have sufficient strength and rigidity to withstand the inertia force generated by the earthquake.
In short, the seismic design of the single-span double-slope steel structure warehouse is a systematic project, which requires comprehensive consideration from multiple aspects such as structural selection, calculation analysis, component design, foundation design and non-structural component design. Only by strictly following the relevant specifications and standards can the safety and reliability of the steel structure warehouse under earthquake action be ensured.