During the process of designing street lights using process models, structural mechanics calculations are crucial for ensuring the pole's wind and seismic performance. Scientific calculations and simulation analysis allow for precise assessment of the pole's mechanical response under various operating conditions, providing theoretical support for optimized design.
Calculating the wind resistance of street light poles requires comprehensive consideration of wind loads, structural shape, and material properties. Wind loads are closely related to wind speed, air density, the pole's frontal area, and the drag coefficient. During design, the base wind speed must be determined based on local meteorological data. Wind pressure at a specific height can be calculated using wind load formulas, incorporating parameters such as ground roughness and height coefficient. The pole's cross-sectional shape directly affects the drag coefficient. Tapered or tapered cross-sections can reduce wind resistance. For circular cross-sections, the calculation of the failure moment requires consideration of the inner diameter, wall thickness, and weld width to ensure that the stress under wind load does not exceed the material's bending strength. Furthermore, dynamic wind effects, such as vortex-induced vibrations, must be evaluated through modal analysis to prevent structural damage caused by resonance.
Calculations of seismic performance must consider earthquake intensity, site type, and the structural dynamic characteristics. Seismic loads are related to the pole's deadweight and peak ground acceleration. Response spectrum analysis or dynamic time-history analysis is required during design to assess the structural response under seismic loads. The pole's foundation type significantly impacts its seismic performance. Concrete or reinforced steel cage foundations effectively disperse seismic energy and reduce the risk of toppling. Furthermore, the connection between the pole and foundation must meet rigidity and toughness requirements to prevent failure during earthquakes. Finite element analysis software can simulate structural deformation and stress distribution under seismic waves, optimizing foundation dimensions and reinforcement to enhance overall seismic resistance.
Material selection and structural optimization are key to improving the wind and earthquake resistance of light poles. High-strength steels such as Q235B carbon steel offer high bending strength and toughness, making them suitable for general environments. 304 stainless steel is recommended for coastal areas to resist salt spray corrosion. 7075T6 aviation-grade aluminum alloy can be used for smart poles to reduce weight while maintaining structural strength. Regarding structural optimization, segmented wall thickness design allows for adjustable wall thickness based on height, such as thickening at the base to resist bending moments and thinning at the top to conserve material. Controlling the perforation ratio can minimize structural strength loss, while the IP55 protection rating of the electrical cavity prevents rainwater intrusion and ensures long-term stability.
The connection method and weld treatment directly impact the overall performance of the light pole. High-strength bolts or welding should be used to connect the battery module bracket to the light pole to ensure a secure and reliable connection. Welds should be widened and deep, and undergo flaw detection to avoid stress concentration caused by weld defects. Flange design should consider the stiffener reaction ratio and bending moment calculation coefficient to ensure that the bolt tension and shear forces meet design requirements. Furthermore, concrete encapsulation of pre-embedded bolts in the light pole improves pullout resistance and prevents collapse in extreme weather conditions.
Simulation analysis and model validation are important means to ensure the scientific integrity of the design. A 3D finite element mechanical model can be used to simulate the stress distribution and deformation of the light pole under wind loads, seismic loads, and deadweight. Static analysis can assess the load-bearing capacity of the structure under normal operating conditions, while dynamic time history analysis can capture the dynamic response under extreme conditions. Model validation requires a combination of theoretical calculations and experimental data to ensure the accuracy of the simulation results. Through simulation analysis, potential weaknesses can be identified, structural form and material selection can be optimized, and overall safety can be improved.
Structural mechanics calculations for street lights must be integrated throughout the entire design process, from the precise calculation of wind and seismic loads, to material selection and structural optimization, to detailed control of connection methods and weld treatment. Ultimately, simulation analysis and model verification ensure the scientific integrity of the design.
