How do you design steel structures to resist natural forces?

1 Wind load

Wind load is the force exerted by the wind on a structure, which depends on the wind speed, direction, shape, and size of the structure, and its surroundings. Wind load can cause bending, torsion, shear, and vibration in steel structures, which can lead to fatigue, buckling, or failure. To design steel structures to resist wind load, you need to calculate the wind pressure and the wind-induced forces and moments on each member and joint of the structure, using codes and standards such as ASCE 7 or Eurocode 1. You also need to consider the dynamic effects of wind, such as resonance and damping, and use appropriate bracing, connections, and detailing to ensure stiffness and strength.

2 Earthquake load

Earthquake load is the force induced by the ground motion during an earthquake, which depends on the intensity, duration, frequency, and direction of the earthquake, and the soil and site conditions. Earthquake load can cause large displacements, rotations, and deformations in steel structures, which can lead to inelastic behavior, cracking, or collapse. To design steel structures to resist earthquake load, you need to estimate the seismic demand and capacity of the structure, using codes and standards such as ASCE 7 or Eurocode 8. You also need to consider the ductility and energy dissipation of the structure, and use appropriate seismic-resistant systems, such as moment frames, braced frames, or base isolation, to reduce the seismic forces and enhance the performance.

3 Fire load

Fire load is the heat generated by a fire in a structure, which depends on the fuel, oxygen, ventilation, and combustion conditions. Fire load can cause thermal expansion, contraction, and stress in steel structures, which can lead to loss of strength, stiffness, and stability. To design steel structures to resist fire load, you need to evaluate the fire resistance and fire protection of the structure, using codes and standards such as ASCE 7 or Eurocode 3. You also need to consider the thermal properties and behavior of the steel and its connections, and use appropriate fire-resistant materials, such as concrete, gypsum, or intumescent coatings, to insulate and protect the steel from high temperatures.

4 Corrosion load

Corrosion load is the deterioration of steel due to chemical or electrochemical reactions with the environment, such as moisture, oxygen, salt, or acid. Corrosion load can cause loss of mass, cross-section, and bond in steel structures, which can lead to reduction of strength, durability, and serviceability. To design steel structures to resist corrosion load, you need to assess the corrosion risk and rate of the structure, using codes and standards such as ASCE 7 or Eurocode 3. You also need to consider the corrosion resistance and protection of the steel and its connections, and use appropriate corrosion-resistant materials, such as stainless steel, galvanized steel, or epoxy coatings, to prevent or slow down the corrosion process.

5 Here’s what else to consider

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