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D8.A.4 Design Parameters

The program contains a large number of parameter names which are required to perform design and code checks.  These parameter names, with their default values, are listed in the following table.

Table 1. Indian Steel Design IS 800:2007 Parameters
Parameter Name Default Value Description
CODE - Must be specified as IS800 LSD

Design code to follow. See TR.48.1 Parameter Specifications.

ALPHA 0.8 A Factor, based on the end-connection type, controlling the Rupture Strength of the Net Section, as per Section 6.3.3:
  • 0.6 = For one or two bolts
  • 0.7 = For three bolts
  • 0.8 = For four or more bolts
ANG 0

The location of the angle section through which the axial load passes by. It will only work if the section is single angle. The options are:

  • 0 = Centroid.
  • 1 = any of the legs.

If the value is zero, it means the member is loaded through centroid. In that case Flexural-torsional buckling will not be checked.

ATG None (Mandatory for Block Shear check)

Minimum Gross Area in Tension from the bolt hole to the toe of the angle, end bolt line, perpendicular to the line of the force.

ATN None (Mandatory for Block Shear check)

Minimum Net Area in Tension from the bolt hole to the toe of the angle, end bolt line, perpendicular to the line of the force.

AVG None (Mandatory for Block Shear check)

Minimum Gross Area in shear along bolt line parallel to external force.

AVN None (Mandatory for Block Shear check)

Minimum Net Area in shear along bolt line parallel to external force.

BEAM 1.0

0.0 = design at ends and those locations specified by the SECTION command.

1.0 = design at ends and at every 1/12th point along member length (default).

CAN 0.0 Beam Type, used for both deflection checks and the limit of bending strength in clause 8.2.1.2:
  • 0 = General Member, no limit used in clause 8.2.1.2, member deflection taken as the distance from the displaced end points of the member (DJ1, DJ2)
  • 1 = Cantilever Member, Md limited in clause 8.2.1.2, member deflection taken as the cantilever deflection as defined D1.B.1.2 Design Parameters .
  • 2 = Simply Supported Member, Md limited in clause 8.2.1.2. The member deflection is taken as the same as a general member.
CMX 0.9 Equivalent uniform moment factor for Lateral Torsional Buckling(as per Table 18, section 9.3.2.2)

CMY

CMZ

0.9 Cm value in local Y & Z axes, as per Section 9.3.2.2.
DFF None(Mandatory for deflection check) "Deflection Length" / Maximum allowable local deflection.
DJ1 Start Joint of member Joint No. denoting starting point for calculation of "Deflection Length".
DJ2 End Joint of member Joint No. denoting end point for calculation of "Deflection Length".
DMAX 1000 in. Maximum allowable depth.
DMIN 0.0 in. Minimum allowable depth.
FU 420 MPA Ultimate Tensile Strength of Steel in current units.
FXTY 0

The fixity of the connection between gusset plate and each end of member. Any value between 0 and 1 is allowed where 1 = Fixed and 0 = Hinged. Default is hinged.

A value between 0 and 1 means the level of fixity that is between hinged and fixed. This value will be used to calculate the coefficients k1, k2 and k3 of table 12 by linear interpolation between their specified values for the two extreme (hinged and fixed) conditions.

FYLD 250 MPA Yield Strength of Steel in current units.
KX 1.0 Effective Length Factor for Lateral Torsional Buckling (as per Table-15, Section 8.3.1)
KY 1.0 K value in local Y-axis. Usually, the Minor Axis.
KZ 1.0 K value in local Z-axis. Usually, the Major Axis.
LAT 0.0 Specifies lateral support of beam, as per Section 8.2.1 and 8.2.2, respectively:
  • 0 = Beam is laterally unsupported
  • 1 = Beam is laterally supported
LST 0 Defines the number of longitudinal stiffeners used:
  • 0 = No longitudinal stiffener
  • 1 = Longitudinal stiffener is provided at 0.2D of web from the compression flange
  • 2 = Longitudinal stiffeners are provided at 0.2D and 0.5D of the web from the compression flange
LX Member Length Effective Length for Lateral Torsional Buckling (as per Table-15, Section 8.3.1)
LY Member Length Length to calculate Slenderness Ratio for buckling about local Y axis.
LZ Member Length Same as above except in Z-axis (Major).
MAIN 180 Allowable Slenderness Limit for Compression Member (as per Section 3.8)
  • 0 = the default value will be used
  • -1 = the slenderness check will not be performed (any other negative value will be ignored
NBL 1 The number of bolts connecting each end of member with the gusset plate. The options are :
  • 0 = one bolt.
  • 1 = two or more bolts or weld.
NSF 1.0 Net Section Factor for Tension Member.
TMAIN 400 Allowable Slenderness Limit for Tension Member (as per Section 3.8)
  • 0 = the default value will be used
  • -1 = the slenderness check will not be performed (any other negative value will be ignored
PROFILE None

Used to search for the lightest section for the profile(s) specified for member selection. See TR.48.1 Parameter Specifications for details.

PSI 1.0 Ratio of the Moments at the ends of the laterally unsupported length of the beam, as per Section 9.3.2.1:
  • 0.8 = where Factored Applied Moment and Tension can vary independently
  • 1.0 = For any other case
RATIO 1.0 Permissible ratio of the actual to allowable stresses.
STP 1 Specifies the section type per Table 2 and Table 10:
  • 1 = Hot rolled section
  • 2 = Welded section
TRACK 0 Controls the levels of detail to which results are reported.
  • 0 = Minimum detail
  • 1 = Intermediate detail level
  • 2 = Maximum detail
TSP 0 Spacing of transverse stiffeners.
TST 0 Used to control transverse stiffeners in design:
  • 0 = No Transverse Stiffener is provided
  • 1 = Transverse Stiffener is provided