EN 1991-1-4 defines and determines natural wind actions for the structural design of buildings. Characteristic peak velocity pressure, qp value calculated by using the terrain features, basic wind velocity, mean wind velocity, etc., is multiplied by the external pressure coefficients to calculate external wind pressure for vertical walls, mono-pitch roofs, and duo pitch roofs.

The analysis settings used for wind Actions is shown below.

A summary of calculation procedures for the determination of wind actions is given below.

Peak Velocity Pressure qp

  • Basic wind velocity, vb

  • Reference height, ze

  • Terrain category

  • Characteristic peak velocity pressure qp

  • Turbulence intensity Iv

  • Mean wind velocity vm

  • Orography coefficient co(z)

  • Roughness coefficient cr(z)

Wind Pressures

  • External pressure coefficient cpe

  • External wind pressure: we=qp cpe

Wind forces on structures

  • Structural Factor cscd

  • Wind force Fw