Auto lateral load FAQ
This page is devoted to frequently asked questions (FAQ) related to auto lateral loads.
On this page:
Modeling and application
How do I assign wind auto-lateral-load conditions?
ANSWER: Wind auto lateral load may be assigned as follows:
Define the wind auto lateral load.
Assign wind-pressure coefficients using the Assign > Area Loads > Wind Pressure Coefficients option.
Is it possible to apply wind load to a specific frame object only?
ANSWER: Yes, wind load may be applied to specific frame objects through the process which follows:
Define a load pattern, designate the type as Wind, and specify the load as an auto-lateral-load pattern, such as ASCE 7-05.
Select Modify Lateral Load Pattern > Exposure from Frame and Area Objects > Include Frame Objects, and define wind-direction angle, along with other parameters.
Designate the specific frame objects for wind auto-lateral-load application through Assign > Frame Loads > Open Structure Wind Parameters.
How is wind load applied per BS standard?
Extended Question: For modeling a Floating Production Storage and Offloading (FPSO) unit as a 3D frame system, how would I apply wind load per BS standard? The Wave Wind form is limited to API standard, and I'm concerned that diaphragm definition would affect analysis.
ANSWER: Two options are available, described as follows:
Define dummy diaphragms then assign each to a single point object. Each point object then becomes the location where wind load is applied. Tributary area is specified using the Wind Exposure Width Data form.
Alternatively, use dummy area objects to apply wind loads using exposure from area objects. This may be specified using the BS 6399-95 Wind Load Pattern menu.
Display
Is it possible to display auto-lateral-load application?
ANSWER: Yes, auto lateral load may be displayed in a tabular format. The seismic auto-lateral-load pattern applied to structural joints, for example, may be reviewed under Model Definition > Load Pattern Definitions > Auto Seismic Loads > Table: Auto Seismic Loads to Joints.
Formulation
How do I find the period used to calculate the auto-seismic load?
ANSWER: All parameters, including structural period, are reported in the table available through Load Pattern Definitions > Auto Seismic Load.