Loss analysis and loss based seismic design for woodframe structures

Light frame wood structures serve as the vast majority of construction type for residential structures throughout North America. Recent earthquake surveys and studies revealed that the costs involved in repairing these structures after earthquakes can be quite significant even when the structure survives the event without collapse. As a result of the large stock of residential construction in the U.S., earthquake-induced losses for this type of structure could have a detrimental financial impact on both the building owner and the community. The limitation of current woodframe structural design philosophy is that it focuses mainly on life safety and does not address providing damage-limitations. The idea that financial losses for a structure during an earthquake should be addressed during the design stage leads to loss-based seismic design, which falls under a more comprehensive framework, performance-based seismic design (PBSD).;The objective of this study is twofold. The first objective is to develop a method to establish a probabilistic model for earthquake-induced loss of existing or newly designed wood frame structures for a given period of time into the future; the second is to incorporate this method into a performance-based seismic design framework to conduct loss-based design/optimization for wood frame structures. The results of the long-term earthquake-induced loss were obtained in the form of simulated sample pools conditional on time span. Simplified loss estimation in the design stage was introduced in order to obtain the vulnerability target for loss based optimization. This optimization procedure was later used to implement loss-based design in the numerical examples.;The most significant contribution of this study to the woodframe design and research communities will be the development of a long-term seismic-induced loss estimation framework/procedure for woodframe structures that enables loss-based design and evaluations. The automated analysis program package, SAPWood, developed in this study will essentially be a practical tool for the implementation of the performance-based seismic design (PBSD) concept for most commonly constructed residential structures (in North America).