D8.C.4 Design Parameters

The following table contains the input parameters for specifying values of design variables and selection of design options.

Note: Once a parameter is specified, its value stays at that specified number until it is specified again. This is the way STAAD.Pro works for all codes.

Table 1. IS 801: Indian cold formed steel design parameters
Parameter Name	Default Value	Description
CODE	-	Must be specified as `IS801` Design code to follow. See TR.48.1 Parameter Specifications.
BEAM	1.0	When this parameter is set to 0) the 13 location check is not conducted, and instead, checking is done only at the locations specified by the SECTION command (see TR.41 Section Specification for details) For TRUSS members only start and end locations are designed. 1) the adequacy of the member is determined by checking a total of 13 equally spaced locations along the length of the member.
CB	0	Bending coefficient Cb used for bending checks. By default (value of 0), this is calculated by the program.
CMY	calculated	Coefficient Cm as per Cl. 6.7 for bending about the member Y axis. See IS:801-1975, 6.7. Used for Combined axial load and bending design. Values range from 0.4 to 1.0.
CMZ	calculated	Coefficient Cm as per Cl. 6.7 for bending about the member Z axis. See IS:801-1975, 6.7. Used for Combined axial load and bending design. Values range from 0.4 to 1.0.
CWY	0	Specifies whether the cold work of forming strengthening effect should be included in resistance computation. See IS:801-1975, 6.1.1 0) effect should not be included 1) effect should be included
FLX	0	Specifies whether the member has torsional-flexural buckling restraints that will in turn determine whether the member is susceptible to flexural-torsional bucking mode. See IS:801-1975, 6.6.1 0) No Torsional restraints provided and the section subject to torsional flexural buckling 1) Torsional restraints provided and the section is not subject to torsional flexural buckling
FU	450 MPa (4588.72 kg/cm²)	Ultimate tensile strength of steel in current units.
FYLD	353.04 MPa (3600.0 kg/cm²)	Yield strength of steel in current units.
KX	1.0	Effective length factor for torsional buckling. It is a fraction and is unit-less. Values can range from 0.01 (for a column completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression.
KY	1.0	Effective length factor for overall buckling about the local Y-axis. It is a fraction and is unit-less. Values can range from 0.01 (for a column completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression.
KZ	1.0	Effective length factor for overall buckling in the local Z-axis. It is a fraction and is unit-less. Values can range from 0.01 (for a member completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression.
LX	Member length	Unbraced length for twisting. It is input in the current units of length. Values can range from 0.01 (for a member completely prevented from torsional buckling) to any user specified large value. It is used to compute the KL/R ratio for twisting for determining the capacity in axial compression.
LY	Member length	Effective length for overall buckling in the local Y-axis. It is input in the current units of length. Values can range from 0.01 (for a member completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression.
LZ	Member length	Effective length for overall buckling in the local Z-axis. It is input in the current units of length. Values can range from 0.01 (for a member completely prevented from buckling) to any user specified large value. It is used to compute the KL/R ratio for determining the capacity in axial compression.
NSF	1.0	Net section factor for tension members. The net area is calculated as `NSF`×gross area.
RATIO	1.0	Permissible ratio of actual to allowable stresses
TRACK	0	This parameter is used to control the level of detail in which the design output is reported in the output file. The allowable values are: 0) Prints only the member number, section name, ratio, and PASS/FAIL status. 1) Prints the design summary including allowable stress in addition to that printed by `TRACK 0`. 2) Prints member, material properties, and stress check table in addition to that printed by `TRACK 1`.
TSA	0	Specifies whether transverse web stiffeners have been provided to check for the requirements of IS:801-1975, 5.2.4. 0) Web stiffeners not provided 1) Web stiffeners provided
UNL	Member length	Unsupported length (in current units) for calculating the allowable bending stress.