Liner Moment Overview

The Liner Moment options in the Loading menu of the RS2 Model program, allow you to define moment and rotation boundary conditions for Liners.

Add Liner Moment

The Add Liner Moment option allows you to apply an active (non-zero) moment load to a Liner.

Add Liner Hinge

The Add Liner Hinge option allows you to specify a zero bending moment condition for a Liner (i.e. the location of a "hinge" which allows the liner to freely rotate at that point).

Liner Moment versus Liner Hinge

It is important to understand the difference between the Add Liner Moment and Add Liner Hinge options in RS2:

• When you define a moment load with the Add Liner Moment option, the moment is applied as an initial loading condition to the Liner.
• When you define a hinge with the Add Liner Hinge option, a zero bending moment condition will be enforced at that point. The Liner will be free to rotate about the hinge. Axial force and shear force in the liner can be transmitted across the hinge location, but the bending moment at the hinge will remain zero throughout the analysis.

A Liner Moment = 0 (applied with the Add Liner Moment option) is NOT equivalent to a Liner Hinge. A Liner Moment = 0 would have no effect on the analysis (i.e. this simply means that no load is applied). For this reason, RS2 does not allow you to add a Liner Moment = 0.

Add Rotation Restraint

The Add Rotation Restraint option allows you to specify a clamped condition (zero rotation) for a point on a liner. This allows you to model clamped conditions at the end of a beam, for example.

Add Liner Connection

The Add Liner Connection option allows you to apply a hinge to connect between liner elements (including liner, composite liner, and structural interface). The hinge can be set as plastic, which contains a moment capacity.

Liner Connection versus Liner Hinge

A Liner Hinge can be applied to any node with single or multiple liners connected, while a Liner Connection can only be applied to any node with multiple liners connected.

Non-plastic Liner Connection vs. Liner Hinge

A Liner Connection without moment capacity behaves similar to a Liner Hinge, while there are differences. For a node with multiple liners connected, if a Liner Connection without moment capacity is applied to one liner, the moment of the liner will be zero (free to rotate about the point), while the rest of connected liner can still have non-zero moments; if a Liner Hinge is applied, all liners connected to the hinge will have zero moment.