Structural Sections

Model Reference Manual

Data Consistency Checking : Setting Geometric Error Limits : Structural Sections

Misalignments of Sections in structural designs are defined in similar terms to those used for pipework, namely in terms of an offset distance, a misalignment angle or a ratio (the tangent of the angle). These are together referred to as the Section’s eccentricity.

Distance and angular offsets are measured from the logical line between Nodes, while additional checks are made using the attached Neutral Points of the Section and the corresponding Nodes. The terminology is illustrated in the following Figure.

Keywords:

ECCENTRICITY SECTION DISTANCE ANGLE RATIO (TOLERANCE)

Description:

The ECCENTRICITY SECTION commands specify the maximum offset distance, angle or ratio misalignments that will be allowed between a Section’s Neutral Axis and the Logical Line between Nodes before a diagnostic message is output.


Examples:
ECC SECT DIST 1 (Default)	Maximum offset for either end of Section is 1 mm
ECC SECT DIST 0.5 INCH	Maximum offset for either end of Section is 0.5 in
ECC SECT ANGLE 0.0573 (Default)	Maximum angular misalignment is 0.0573 degrees
ECC SECT RATIO 0.001 (Default	Maximum offset/node separation ratio is 0.001
ECC SECT ANG 1.5	These are equivalent angular settings, since
ECC SECT RAT 0.0262	0.0262 is the tangent of the angle 1.5 degrees
ECC SECT DEF	Resets all misalignment eccentricities (Offset distance, Angle and Ratio) to their default values

Command Syntax:

>-- ECCentricity -- SECTion --+-- DISTance --+-- <uval> -->
                              |              |
                              |              ‘-- DEFault -->
                              |
                              |-- ANGle --.
                              |           |
                              |-- RATio --+-- value -->
                              |           |
                              |           ‘-- DEFault -->
                              |
                               ‘-- DEFault -->

Querying:

Q TOLerance ECCentricity --- SECTion ---+--- DISTance ---.
                                        |                |
                                        |--- ANGle ------|
                                        |                |
                                        |--- RATio ------|
                                        |                |
                                         ‘----------------+--->

Note:

The TOLERANCE keyword is used here to distinguish between the eccentricity limit that the user has specified and the actual eccentricity derived from the structural model.