Input Truss Member

PURPOSE: Define truss member locations.

Parameters

tbTrussMember

Field

Type

Units

Description

Name

text

Truss member name

Type

text

[B|T|C|D|V] Member type code. BOTTOM, TOP, CORD, DIAG, VERT If B,T,or C use Mom rider only loads. If D or V use Shr rider only. Blank=both riders.

StartPoint

text

Name of COGO point at start of truss 2

EndPoint

text

Name of COGO point at end of truss

AutoCn

text

[N|Y|YS|A|AS] Automatically connect with intersecting lines and points.

Shape

text

Select shape from either Plate, Std.Shape, or Built-up libraries.

BetaAngle

real

DEG

Beta Angle

NegFArea

real

IN2

Area of fastener holes (sqi)

NegHArea

real

IN2

Area of hand holes (sqi)

RelEndA

text

Member end releases at end A

RelEndB

text

Member end releases at end B

MajEffL

real

Kz Major axis of bending effective length factor (Kz factor).

MinEffL

real

Ky Minor axis of bending effective length factor (Ky factor).

StageIn

int

Stage that member becomes active in the analysis.

StageOut

int

Stage that member is removed from the analysis (Member is not active in this stage).

Slender

chr

[Y|N] Treat as slender member (default is No)

Reduce

real

If slender, override any shape slenderness reductions (using Q = Reduce)

ShearLag

real

Shear lag reduction factor (U = ShearLag) (see AASHTO 6.8.2.1)

TCCode

chr

[ |T|C] Tension or compression only.

RateFactor

text

Rating Factors (from tbRatingFactorsLFRDef or tbRatingFactorsLRFRDef)

LLDF_ID

text

LLDF Factors from tbLLDF_LRFR (for LRFR only; LFR uses tbRatingFactorsLFRDef)

LBL

real

INC

Local Buckling Length

Cond

real

Condition factor (phi_c; default = 1.00) – the system factor as defined in AnalysisControls will be added by SteelBridg

Note

If the Local Buckling length is not entered, then no local buckling length check is performed. A warning is issued that no local buckling length check has been done.

If a member’s TCCode is T then that member will only be checked for tension rating, and if it is C then that member will only be checked for compression rating.
The Type field is [B|T|C|D|V] for code: BOTTOM, TOP, CORD, DIAG, VERT If B,T,or C use Mom rider only loads. If D or V use Shr rider only. Blank=both riders.
The effective length of a member is it’s node to node distance times the effective length factor. For calculations that involve the major axis of bending, bending about the local Z axis, the effective length factor MajEffL is used. For bending about the minor axis, the local Y axis, the factor MinEffL is used.