To automatically calculate the effective length parameters for steel design for a parameter block, use the following procedure.
Tip: One or more steel design
parameter blocks must be defined in the model before the Effective
Length Calculator tool can be used.
The effective length calculator tool is
used to automatically calculate the KY
, KZ
,
LY
, and LZ
parameters used for steel design.You
may select members in the model before using this tool to pre-populate the member
list, or use one of several methods (typed lists, graphical selection, or by group
name) to specify members while using the tool.
-
On Steel Design - Whole Structure dialog,
click Effective Length.
The Effective Length
Calculator dialog opens.
-
Select which Parameter Block to which the effective
length parameters will be added.
- Optional:
Provide lateral restraint information for the members:
-
Select the local directions (with respect to the member orientation)
which are restrained.
-
Type the Theta angle is connected members which
are not normal to the member also provide restraint.
Connecting members
are assumed to provide lateral restrained against buckling when the
connect to the member. However, members which connect at a shallow
angle may not provide sufficient restraint. The angle, θ (theta), is
the angle away from 90° to the member at which connecting members
should can no longer provide sufficient restraint. Angles between 0°
and 80° (inclusive) are allowed. A value of zero indicates that
only normal members provide restraint.
-
Type the Colinearity tolerance to use for
establishing if members are colinear.
The program uses this to determine the
effective lengths for adjacent, colinear analytical members. When
the longitudinal axis (i.e.., local x axis) of two adjacent members
differs by greater than this angle, the program will no longer
assume they are the same member for automatic calculations of the
effective length.
-
Specify the list of members to which these parameters will be assigned using
one or more of the Assignment methods:
-
Member List - the list of
members which are assigned
-
Select on Model - click to
active the selection mode. Then click on members in the view
window to add these to the Member List.
Click this tool again to deactivate selection mode.
-
Select Group - click to open
the dialog, which
is used to select members by previously defined
group names.
Tip: Click Highlight to
show which members will be assigned.
-
Click Add.
The effective length related parameters
(KY
, KZ
, LY
, and
LZ
) are added to the parameter block.