The modeling and response of curved frame objects is approximated by a series of linear segments. The Number of Linear Segments parameter on the Curved Frame Geometry menu may be edited to change the quantity of line segments. Object curvature becomes more closely modeled with an increasing number of linear segments.

Modeling arch behavior

During analysis, loads applied to curved objects are resolved into axial forces and flexural moments. These values are dependent upon the configuration of both loading and structural geometry. If an arch is well-designed, and exhibits true arch behavior, applied loading will be carried by axial forces. Please note that a change in load application without a change in the structural model may still introduce an applied moment. This may occur when a symmetrical arch system is subjected to an asymmetrical load pattern.

Arch design

Software will design the frame object which correlates with each linear segment of a curved member. First, the system must be modeled, then the number of line segments is specified on the Curved Frame Geometry menu.