A potential upcoming project will require evaluation be ASCE 31-03 at both the Tier 1 and Tier 2 levels. A quick glance of the plans and it would be a "C3" concrete frame with unreinforced masonry and rigid diaphragms. There are irregularities that I believe will require the application of the Linear Dynamic Procedure during the Tier 2. Does anyone know of a good reference for how to model and analyze this system for the evaluation? ASCE indicates they behave as a shear wall thru the development of compression struts in the wall for a period until the wall is destroyed and then it transitions to frame frame behavior but I am not sure how to capture this behavior numerically or in a 3d model for the dynamic analysis.
-Michelle