Many publications, documents, codes and guidelines exist related to the seismic evaluation and rehabilitation design of existing buildings. This report discusses the assumptions and methods employed for investigation of two wood structures using four references: FEMA 154, FEMA 356, ASCEI per SEI 31, and 1997 UBC. The screening performed using FEMA 154 demonstrates the importance of conducting pre-inspection investigation of existing documentation such as construction drawings. In the absence of this information, the screening indicated that the structures would not require additional evaluation. A plans check revealed a deficiency in the structural systems, that if included in the evaluation, would mark them for additional analysis. This investigation examines the demand-to-capacity ratios for shear walls and roof diaphragms in the two wood-framed structures. It was expected that requirements for the design of new structures in the 1997 UBC would be the most conservative of these references. It was also expected that the rehabilitation design provisions of FEMA 356 would be more conservative than the existing building evaluation provisions in ASCE per SEI 31. The results of this study show that the new building design provisions in the 1997 LJBC are not necessarily conservative when compared to the rehabilitation design provisions in FEMA 356. In addition, the provisions in the design documents FEMA 356 and the 1997 UBC are not necessarily conservative when compared to existing building evaluation provisions in ASCE per SEI 31. The likely cause of the unexpected results is the conservative Linear Static Procedure and associated m factors for wood in the FEMA 356 and ASCE per SEI 31 documents. Additional research is needed to better calibrate these factors and associated acceptance criteria to account for duration of shaking, the number of cycles of nonlinear behavior, redundancy, etc.
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