Wind loads may be input manually or may be program generated for equipment foundations. This automated calculation of wind loads therefore is only available in Foundation3D.
To have the program calculate the wind loads on equipment, select workspace settings of the equipment workspace and then select "Wind Loads" to display the Wind Load Parameters page. Check or select "Program Calculated Loads" option. Then select the following parameters:
Wind Code: Select from ASCE 2016, 2010 or 2005
Basic Wind Speed in mph for English units and in m/s for SI units
Force Coefficient
Exposure Category
Gust Factor: -1 indicates "use program computed gust factor". You can also manually enter or select from one of the drop-down values
Wind or Height Factor
Importance Factor
Foundation3D calculates the wind load on equipment such as horizontal exchanger, horizontal vessel and vertical vessel in the following manner:
If the effective diameter/length fields are empty or zero, the wind load is calculated according to the simplified method recommended by the ASCE task committee on “Wind loads on petrochemical structures”. For details see Wind Design Code
If the effective diameter/length fields are non-zero, the wind load is calculated considering these effective dimensions.
Foundation3D calculates the wind load on the horizontal exchanger/vessel and the pier as follows:
Total transverse wind load = transverse wind load on the exchanger(s) + transverse wind load on a pier * 2 (for 2 supports)
Transverse wind load on the exchanger(s) = projected diameter of the exchanger * projected length of the exchanger * wind pressure
Transverse wind load on a pier = pier height above grade * pier dimension in the longitudinal direction * wind pressure
Transverse wind moment calculation:
The moment values are resolved to the top of the pier as follows:
Total transverse moment at the top of the pier = transverse moment due to the total wind load applied at the centerline of the exchanger(s) - transverse moment due to the wind load on the piers
Transverse moment due to total wind load applied at the centerline of the exchanger(s) = total transverse wind load * (distance between C.L. of the exchanger(s) and the top of the pier)
Transverse moment due to the wind load on the pier = transverse wind load on the pier * (pier height above grade/2)
Total longitudinal wind load = longitudinal wind load on the exchanger(s) + longitudinal wind load on a pier * 2 (for 2 supports)
Longitudinal wind load on the exchanger(s) = (PI * projected diameter ^ 2)/4 * wind pressure
Longitudinal wind load on a pier = pier height above grade * pier dimension in the transverse direction * wind pressure
Longitudinal wind moment calculation:
The moment values are resolved to the top of the pier as follows:
Total longitudinal moment at the top of the pier = longitudinal moment due to the total wind load applied at the centerline of the exchanger(s) - longitudinal moment due to the wind load on the piers
Longitudinal moment due to the wind load applied at the centerline of the exchanger(s) = total longitudinal wind load * (distance between C.L. of the exchanger(s) and the top of the pier)
Longitudinal moment due to the wind load on the pier = longitudinal wind load on the pier * (pier height above grade /2)
The longitudinal moment is then resolved into a compression - tension force on each pier.
If the effective diameter/height fields are empty or zero, the wind load is calculated according to the simplified method recommended by the ASCE task committee on “Wind loads on petrochemical structures”. For details see Wind Design Code
If the effective diameter/ height fields are non-zero, the wind load is calculated considering these effective dimensions.
The shape factor Cf is used in calculating the transverse wind load. However the shape factor for calculating the longitudinal wind load is always considered as 1.0.