Helmut G. L. Prion

Analysis and design of steel plate walls: analytical model

A simple rational model is developed in this paper to determine the structural behavior of steel plate wall (SPW) systems, and is referred to as the Modified Plate–Frame Interaction (M-PFI) model. The model considers bending and shear behavior, and the interaction of the two, for the SPW system. It is a modification of the Plate–Frame Interaction (PFI) model that only considers the shear response of the SPW system. The proposed M-PFI model can determine force and displacement values that correspond to the pre- and post-critical buckling state, the yield state, and the ultimate capacity of individual panels. In the end, design requirements for the beams and columns (also known as horizontal and vertical boundary elements) of the SPW are derived using the underlying theory of the M-PFI model.

Influence of imperfections on the strength of unstiffened, fabricated, tubular beam-columns

Abstract Fabricated tubular steel members are used in offshore structures as primary and secondary members; typical applications in fixed structures incorporate large diameter tubes in truss-type assemblies. These unstiffened tubes are formed by rolling plate into cylindrical components which are then seam and girth welded to create the circular tubular shape. The members produced in this fashion have characteristic imperfections which are different from those found in smaller diameter seamed or seamless hollow structural and pipe sections. These imperfections and their influence on the structural behaviour of beam-columns are subject of the study and results presented here. Earlier experimental studies at the University of Toronto on the influence of fabrication parameters are the foundation of the results reported here. Extensive measurements of as-fabricated geometry provided information on actual shape and these measured geometries are used to establish the analytical models using a finite element program, ANSYS; this program permits the modelling of non-linear material and geometric effects. The ultimate and post-ultimate local buckling behaviour was studied in the analyses to the same extent as observed in experiments. The load-displacement behaviour of tubular members depends significantly on the tube geometry and material properties. The discretization of the tube into elements is shown to require careful consideration so that potential deformation modes are not missed. Bilinear kinematic hardening material based on coupon tests of the ‘as fabricated’ steel, in combination with geometric modelling techniques yielded a behaviour response with a close resemblance to the experimental observations and measurements. The relative importance of various parameters is discussed and direct comparisons of experimental and analytical results with current code resistance formulations are made. The specific effects of residual strains are not addressed in this paper.

Experimental evaluation of an orthotropic, monolithic, modular wooden-dome structural system

Canadian Wooden Dome (CWD) is an innovative orthotropic, monolithic modular sectional building system. The main frame of these structures is built using mill trim ends that are normally chipped or used for finger-jointing. The structure, in comparison to conventional wood-frame single-family housing, has a rapid manufacturing process, and quick, on-site assembly attempts to reduce overall construction time. Presented with these advantages and the uniqueness of the wooden-dome system, a technical study was initiated to investigate the structural performance of the modular wooden dome in earthquake-prone areas and to examine its load resistance to heavy snow. This paper describes the results from a series of static and dynamic load tests conducted on the CWD as part of this study. The test results generally indicated that based on the structural performance of the CWD under static and dynamic loads, the CWD could be an alternative to the conventional wood-frame construction system. The test results are then...