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Chinese Steel Design Parameters dialog

Used to add a parameter definition to the model for use in Chinese steel design.

Opens when the Add or Edit button is clicked on the Chinese Steel Design Parameters - Whole Structure dialog.

Note: Some parameters are code-specific as noted below.

General Parameters tab

SettingDescription
Parameter Name Type a unique label used to identify the parameter set.
Steel No Select the steel grade used (independent of any steel grade assigned as part of a material definition).

For GB50017:

  • Q235 (default)
  • Q345
  • Q355
  • Q390
  • Q420
  • Q460
For GB50018:
  • Q235CF
  • Q345CF
Refer to Steel Grade for additional details.
Consider Cold Forming Effect (GB50018 only) Check to consider cold-forming effect for bending and truss strength per Appendix C.
High Frequency Welding (GB50018 only) Check to get the η value per Appendix.
Member Type Select the member type for design:
  • Automatic (default) - the actual type of the member is determined by the program based on the Principle selection.
  • Bending - a beam for which bending (MZ, MY) are considered but axial force (FX) is ignored for design.
  • Truss - only axial force (FY) is considered for design.
  • Column - both moment and axial force are considered for design.
  • Defined - for this type of member, the provisions for code checks are all user-defined.
Refer to Member Type for additional details.
Principle Select the option which the program should use to determine the member type for Automatic:
  • Geometry - uses the geometric conditions of the member for selection as follows:
    geometric condition member type
    member in a horizontal plane bending
    member with a truss specification truss
    any other condition column
  • Stress Feature - uses the stress conditions of the member for selection as follows:
    stress condition member type
    no axial force bending
    no bending moment truss
    any other condition column
Refer to Member Type for additional details.
Check as Cantilever Member (GB50017 only) Specify any cantilever member checks:
  • None (default)
  • Both - both major and minor axes
  • Major Axis
  • Minor Axis
Truss Secondary Moment (GB50017 only) When this option is checked, the stability of axial members is per Cl. 8.5.2 and axial members are designed for strength per Cl. 8.5.2.
Section Slenderness Grade (GB50017 only) Select the slenderness grade to check the width-to-thickness ratio of beam and column members per Table 3.5.1:
  • S1
  • S2
  • S3 (default)
  • S4
  • S5
Use Axis forced member Post-Buckling (GB50017 only) When this option is checked, the post-buckling strength is checked per Cl. 7.3.3 for members whose width to thickness ratio exceeds the limits in Cl. 7.3.4.
Displacements Load List Click […] to open the Select Load Case for Displacements dialog, which is used to select the load cases and combinations which the program should use for displacement checks.
Fatigue Check Request (GB50017 only)
Force Loads List Click […] to open the Select Load Case for Design dialog, which is used to select the load cases and combinations which the program should use for design checks.
Optimize Design

When this option is checked, members using this design parameter set participate in the design optimization (used with the optimization option).
Failure Ratio Above Members whose design ratio (calculated / allowable stress) exceeds this value will be shown as Failed.
Safety Ratio Below Members whose design ratio (calculated / allowable stress) falls below this value will be shown as Minimal (i.e., overly conservative).

Seismic Design tab

(GB50017 only) Available when the General Design mode is selected.

SettingDescription
Seismic Adjusting Factor Check this option to specify the seismic adjusting factor values for Stability and Strength checks from the following:
  • Auto (default)
  • 0.75
  • 0.8
  • 1.0
Seismic Measure Grade Select the levels as per Clauses 8.3.1, 8.3.2, and 8.4.1 and from Table 8.3.2. Select from the following:
  • None (default)
  • Level 1
  • Level 2
  • Level 3
  • Level 4
Reduction Factor of Bearing Capacity

Specify an optional value (less than 1.0) used for checking requirements of full plastic bearing capacity of left and right beam ends and upper and lower column ends of beam column joints per the exceptions in Cl. 8.2.5.

Performance Design tab

Available when the Performance Design mode is selected. Performance design is disabled for members of type Defined Member.

SettingDescription
Performance Design Check to instruct the program to use performance design for seismic. Unchecked, the program will only perform the common design.
Structure Type For truss members, the following structure types are available:
  • Frame with cross brace
  • Frame with eccentric brace
  • Brace
For beam and column members, the following structure types are available:
  • Frame structure
  • Frame with cross brace
  • Frame with eccentric brace
Performance Grade Select the performance grade from 1 to 7. You may also check the User Define box to manually type a value.
Precautionary category of building Select the precautionary category and then associated Ductility Grade as listed in Table 17.1.4-2 of GB 50011-17.
Member Performance Factor This will be automatically calculated unless the Calculated by Program option is unchecked. Then you may manually type a value for design.
Force adjustment coefficient for elastic zone
Steel super strength coefficient
Dissipated Region Length

Allowable Slenderness tab

SettingDescription
Allowable Compression Slenderness Select the allowable value of slenderness ratio for members in compression:
  • Auto (default) - the value is determined as per Table 7.4.6
  • 150
  • 200
Allowable Tension Slenderness Select the allowable value of slenderness ratio for members in tension:
  • Auto (default) - the value is determined as per Table 7.4.7
  • 200
  • 250
  • 300 (GB50017 only)
  • 350
  • 400 (GB50017 only)
Seismic Brace, GB50011-2010 8.4.1 (GB50017 only) Check this option to include checking slenderness of brace members per Cl. 8.4.1.
Seismic Multi-storey Plant, GB50011-2010 H.2.8 (GB50017 only) Check this option to include checking slenderness of multi-story industrial structures per Cl. H.2.8.
Seismic Column, GB50011-2010 8.3.1 (GB50017 only) Check this option to include checking slenderness of frame columns per Cl. 8.3.1.
Seismic Single-storey Plant, GB50011-2010 9.2.13 (GB50017 only) Check this option to include checking slenderness of single-story industrial structures per Cl. 9.2.13.

Plastic Development Factor tab

(GB50017 only) The plastic development coefficient is a coefficient related to the shape of the section. The coefficient can be according to article 6.1.2 8.1.1 of the specification. If you enter the design parameters γz, γy, γsharp, the program will use those values. If you select to use automatic calculation, the program will use values for γz, γy, γsharp as specified in Plastic Development Coefficients γx, γy, γsharp.

SettingDescription
Major Axis (Z Axis) The γz value.
  • Auto (default)
  • 1.05
  • 1.20
Minor Axis (Y Axis) The γy value.
  • Auto (default)
  • 1.05
  • 1.20
Sharp (Tee/Double Angle/Channel) The γsharp value.
  • Auto (default)
  • 1.05
  • 1.20

Equivalent Moment Factor tab

The equivalent moment coefficient is used to "correct" the bending moment when checking the stability of the solid web bending member with bending moment acting on the symmetry axis plane, so it is divided into in-plane equivalent moment coefficient and out of plane equivalent moment coefficient. These coefficients can be calculated automatically by program or manually input.

SettingDescription
Equivalent Moment Factor in-Plane
  • Auto (default)
  • 1.00
  • 0.85
  • 0.65
Equivalent Moment Factor out-Plane
  • Auto (default)
  • 1.00
  • 0.85
  • 0.65
Lateral Load Along Local y
  • Auto (default)
  • 1.00
  • 0.85
  • 0.65
Lateral Load Along Local z
  • Auto (default)
  • 1.00
  • 0.85
  • 0.65

Deflection Parameters tab

Refer to Deformation Parameters for additional details.

SettingDescription
Span/Deflection (DFF) Select the span-to-deflection ratio limit:
  • 150
  • 200
  • 250
  • 300
  • 350
  • 400 (default)
  • 500
  • 600
  • 750
  • 1,000
Start Joint (DJ1) Select the starting joint used to define the member for deflection checking:
  • Auto - forms a continuous beam
  • Member start joint - selects the current member start joint
End Joint (DJ2) Select the ending joint used to define the member for deflection checking:
  • Auto - forms a continuous beam
  • Member end joint - selects the current member end joint
Check Horizontal Section Displacement Check this option to check horizontal displacement in addition to the vertical displacement in calculation of deflections against limits. Disabled for column member types.

Stability Factors tab

The stability coefficient is divided into overall stability coefficient of flexural member (beam) and stability coefficient of axial compression member (truss). The program can automatically calculate the coefficients according to the section type and force characteristics of the designed member as described in Stability Coefficient.

SettingDescription
Overall Stability Factor of Beam
SettingDescription
Major Axis (Z Axis)
  • Auto
Minor Axis (Y Axis)
  • Auto
Stress Feature (GB50017-2017 Appendix Table C.1) (GB50017 only)
  • Type1
  • Type2
  • Type3
  • Type4
  • Type5
  • Type6
  • Type7
  • Type8
  • Type9
  • Type10
Beam Bearing Type (GB50018 only)
Lateral Support (GB50018 only)
Stability Factor of Axial Compression
SettingDescription
Major Axis (Z Axis)
  • Auto
Minor Axis (Y Axis)
  • Auto
Axial Compression Section Type (GB50017 only)
SettingDescription
Major Axis (Z Axis)
  • Auto
  • Class a
  • Class b
  • Class c
  • Class d
Minor Axis (Y Axis)
  • Auto
  • Class a
  • Class b
  • Class c
  • Class d
Restraint coefficients (GB50018 only) Refer to Table 5.2.4 of GB50018 for details.
SettingDescription
Having Batten Plate
Batten Plate Spacing
Bearing Status

Effective Length tab

The unsupported effective length and effective length coefficient are the calculation parameters needed to check the stability of members. The direction of the strong axis and the weak axis of the principal inertial axis should be considered respectively. For complex structures, it can difficult to select the effective length and effective length coefficient of members. Therefore, the program can automatically compute these values. When these coefficients are automatically calculated by the program, they are calculated as described in Unsupported Effective Length and Effective Length Coefficient. The values may also be user-specified.

SettingDescription
Unbraced Length The unbraced length (in meters) of the members, in both the Major Axis (Z Axis) and Minor Axis (Y Axis).
Effective Length Select the member bracing condition in the Brace Type drop-down. Then, specify the effective length coefficients, μ z (Major Axis (Z Axis)) and μ y (Minor Axis (Y Axis)).
Note: If the current solution set is set to use a P-Delta analysis type, then the effective length options are disabled. An effective length of 1.0 is used for all design parameter sets for this solution set type.
Gyration Radius Calculation of Single Angle Select the option to use for the radius of gyration for single angles:
  • Parallel Leg Calculation (Y-Z Axis) - the geometric axes
  • Strong Weak Axis Calculation (U-V Axis) - the primary axes
Refer to Rigid Fixed Stepped Column at the Lower End of Frame of Single Story Workshop for details.

Detailing Checks tab

The structural requirement parameters specified here refer to the limits of flange width thickness ratio and web height thickness ratio, as well as the section type of axial compression members. Generally, this parameter is automatically calculated by the program. However, in order to make it easier for users to design the program more flexibly, you can also set the parameters required here. Refer to Construction Requirements for details.

SettingDescription
Flange Slenderness Limit (b/t) (GB50017 only)
  • Auto
Web Slenderness Limit (h0/tw) (GB50017 only)
  • Auto
Include check for web of H profiles in a Truss as per GB50017-2017, Table 8.5.2 (GB50017 only) Check this option to use the values for Table 8.5.2 instead.
Unstiffened Flakiness Ratio Limit (GB50018 only) Options depend on steel grade selection. Refer to Table 4.3.2 in GB50018.
Partially Stiffened Flakiness Ratio Limit (GB50018 only) Options depend on steel grade selection. Refer to Table 4.3.2 in GB50018.
Stiffened Flakiness Ratio Limit (GB50018 only) Options depend on steel grade selection. Refer to Table 4.3.2 in GB50018.
Lip Flakiness Ratio Limit (a/t) (GB50018 only) Refer to Table 5.6.4 in GB50018.

Section Factor tab

The net section coefficient refers to the ratio of net section to gross section area and section modulus (temporarily replaced by net section modulus coefficients An, Wnz, and Wny). The default value is 1.0. Refer to Section Coefficient for details.

SettingDescription
Net Section Factor
SettingDescription
Net Area Factor (An/A) Type a value to use for the net section area to gross area ratio.
Net Resistance Moment Factor (Wny/Wy) Type a value to use for the net moment resistance to gross section moment resistance ratio about the y direction.
Net Resistance Moment Factor (Wnz/Wz) Type a value to use for the net moment resistance to gross section moment resistance ratio about the z direction.
Effective Section Factor of Axis Force (nA) (GB50017 only) Type a value to use for the net section area to gross area ratio.
Reduce Factor (GB50017 only)
SettingDescription
Reduce Strength of Angle Section (Ref. 7.6.1) Check this option to use a re
Strength Reduction
  • Auto
  • 0.70
  • 0.85
  • 0.90
Stability Reduction
  • Auto
  • 0.70
  • 0.85
  • 0.90
Unequal Angle Connection
  • Short leg
  • Long leg (default)

Optional Checks tab

Optional checks based on the selected member type. Any of the checks can be un-selected to prevent that check from being performed.

For bending members:

  • Beam Bending Strength
  • Beam Deflection
  • Flange Slenderness (GB50017 only)
  • Overall Stability
  • Equivalent Stress (GB50017 only)
  • Web Slenderness (GB50017 only)
  • Shear Strength
  • Compressed Flakiness Ratio (GB50018 only)
  • Lip Flakiness Ratio (GB50018 only)

For truss members:

  • Compression Flange (GB50017 only)
  • Compression Shear (GB50017 only)
  • Compression Stability
  • Compression Web Slenderness (GB50017 only)
  • Compression Slenderness
  • Truss Strength
  • Tension Slenderness
  • Compressed Flakiness Ratio (GB50018 only)
  • Lip Flakiness Ratio (GB50018 only)

For column members:

  • Column Strength
  • Compression Flange Slenderness (GB50017 only)
  • Compression Slenderness
  • Compression Web Slenderness (GB50017 only)
  • Shear Strength
  • Stability around Z Axis
  • Stability around Y Axis
  • Tension Slenderness
  • Compressed Flakiness Ratio (GB50018 only)
  • Lip Flakiness Ratio (GB50018 only)
For defined members:
SettingDescription
Strength Select the strength check:
  • Beam Bending Strength
  • Truss Strength
  • Column Strength
Stability
  • Overall Stability
  • Compression Stability
  • Stability around Z axis
Flange Slenderness (GB50017 only)
  • Flange Slenderness
  • Compression Flange Slenderness
Web Slenderness (GB50017 only)
  • Web Slenderness
  • Compression Web Slenderness
Other
  • Shear Strength
  • Compression Shear (GB50017 only)
  • Equivalent Stress (GB50017 only)
  • Stability around Y axis
  • Beam Deflection
  • Compression Slenderness
  • Tension Slenderness
  • Compressed Flakiness Ratio (GB50018 only)
  • Lip Flakiness Ratio (GB50018 only)
Parent topic: Chinese Steel Design tab
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