In recent time, some of the construction processes of multi-storey timber buildings are achieved by using prefabricated volume modules since this method is very beneficial due to its high prefabrication level and the fast on-site assembly of the modules. The main structural component of these modules is a light-frame shear wall that stabilizes these modules from the effect of horizontal forces. A shear wall typically consists of timber frame with studs and rails and sheathing panels connected by dowel type fasteners to one or both sides of the frame. The structural behavior of shear wall and its racking performance is controlled by adequate design of its mechanical joints where sheathing-to-framing joints is the key issue in evaluating the overall behavior of shear wall. This study mainly deals with modelling of light-frame shear walls based on linear elastic characteristic for sheathing-to-framing joints. The objective of this study is to create two effective computer-based models (beam-spring-shell and beam-spring-shell-solid) to predict linear behavior of light-frame shear walls. In addition, the study deals with an experimental investigation of various types of short light-frame shear walls. Finally, the study compares modelling and experimental results to verify that they are in good agreement and that an efficient FE model is able to predict the structural behavior of shear walls for a short computational time. The study optimizes use of beam-spring-shell model which is as reliable as the beam-spring-shell-solid model, emphasizing its advantages over the resource-consuming solid model. The beam-spring-shell model is efficient and can be implemented and used for design and analysis of modular-based timber buildings.

ABSTRACT EFFECT OF INITIAL SUPPORT OF EXCAVATION ON SEISMIC PERFORMANCE OF CUT AND COVER STRUCTURES Rezaei, Hamidreza M.Sc., Department of Civil Engineering Supervisor: Asst. Prof. Dr. Alp Caner MAY 2011, 66 pages The effect of the initial support and its embedment depth, on the seismic performance of cut and cover tunnels is investigated. Cut and cover construction is one of the fastest and cheapest methods for constructing rectangular shallow tunnels. Construction of cut and cover structure in soil usually starts with installation of the initial support of excavation system, which may consists of rigid type of initial supports such as tangent piles or secant piles. These systems usually remain in place after completion of the final structure. However, to simplify the design, it is a common practice to ignore the contribution of initial support. In this study the effect of initial support of excavation on the seismic performance of cut and cover tunnels is investigated by means of a detailed dynamic finite element analysis. Three different tunnel geometries, three soil types and three acceleration histories were considered Results of the study show that depending on the soil stiffness (soft, medium, or stiff soil), the dynamic response of the tunnel deformations are affected significantly by the initial support of excavation. The effect of the initial support diminishes as the quality of the soil improves. Therefore, dynamic analyses are recommended for the final design of this type of structures especially in soft soils.