STAAD Foundation Advanced Help

Wind Load Generation page

Used to input wind load parameters. There are two methods for specifying wind load on a vertical vessel:

  • Directly input the shear force & moment values
  • The program can calculate those values using ASCE 7-2005 (US) or IS-875 III (Indian). The inputs are described in the page, along with code section and/or table numbers for reference.
SettingDescription
Partial Wind Case % This value represents percentage of full wind speed used in case of test load or erection load combination. As probability of getting full wind speed while test is being carried out is very low.
SettingDescription
< Previous

Steps the Wizard to the previous step.

Next >

Proceeds the Wizard to the next step.

Cancel

Exits the Wizard without creating a new Vertical Vessel Footing job.

User Defined Wind Load

SettingDescription
Shear Value Specify a base shear due to wind, in the selected units.
Moment Value Specify a base moment due to wind, in the selected units.

Calculated Wind Load - US Code

SettingDescription
Wind Speed You need to input the wind speed provided in the code in miles per hour unit.
Kd (Wind Directional Factor)

Click on the Table 6.6 button to open the table of code Kd values.

Select a value and then click the OK button to use it.

Note: You may manually enter in any value to override the code-specified table values.
Kz (Velocity Pressure Exposure Coefficient) This is described in section 6.5.6.4 and Table 6.5. Choose the required combination of combo boxes for them.
Kzt (Topographic Factor) This is defined in section 6.5.7.2 and determined from figure 6.2.
I (Importance Factor)

Importance is defined in section 6.5.5 and determined from figure 6.1. Click on the Table 6.1 button to open a table of code I values.

Select a value and then click the OK button to use it.

Note: You may manually enter in any value to override the code-specified table values.
G (Gust Effect Factor) This is the Gust Effect Factor and it is user defined.
Cf (Net Force Coefficient) Value of “Cf” according to table T6-10.

Program Calculated Wind Load - Indian Code

SettingDescription
Wind Speed Specify the wind speed provided in the code in meters per second.
No of Years (N)

Specify the mean probable design life of the structure.

Risk Level (Pn) The risk level in N consecutive years.
Cf Force coefficient.
K3

Topography factor as defined in section 5.3.3 of IS-875 III

Site Class Select the site classification as defined in Section 5.3.2.1 of IS-875 III.
Terrain Category Select the category which describes the surrounding terrain as defined in Section 5.3.2.2 of IS-875 III.