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This paper proposes an updated approach to incorporating relative sea level rise in the estimation of flood construction levels in British Columbia, which are required in coastal planning and infrastructure development. Initially, current guidelines for British Columbia are outlined, and recent information on projected relative sea level rise is summarized. Then, recognizing the uncertainty in sea level rise projections, a probabilistic model of estimating the contribution of relative sea level rise to the flood construction level is described, relying on an available theoretical formulation that is corroborated by the application of a Monte Carlo simulation method. An updated approach to incorporating relative sea level rise in the estimation of flood construction levels is thereby recommended, relying on available data portals for relative sea level rise. Finally, the estimation of the probability of overtopping is described, and the implications of this for making informed decisions on flood construction levels with respect to risk assessments are indicated. [ABSTRACT FROM AUTHOR]

Controlling air leakage through the building envelope remains a challenge, especially in light of the imperative to transition to a net-zero energy building sector and the increasing importance of indoor air quality during extreme weather events such as wildfires. The British Columbia Energy Step Code is a performance-based compliance option in the British Columbia Building Code which is intended to provide a transition pathway to net-zero energy ready construction by 2032. For small residential buildings, performance targets entail thresholds for the measured air leakage rate through the building envelope. This paper reports on the airtightness of the first 145 single- and two-family dwellings built under the Energy Step Code in Richmond, BC. Although the first phase of the implementation of the Energy Step Code in Richmond entailed no airtightness targets (only testing), results indicate improvement compared to the historical levels of airtightness in the region. [ABSTRACT FROM AUTHOR]

The discharge and stage measurements in a river system are characterized by a number of sources of uncertainty, which affects the accuracy of a rating curve established from measurements. This paper presents a fuzzy set theory based methodology for consideration of different sources of uncertainty in the stage and discharge measurements and their aggregation into a combined uncertainty. The uncertainty in individual measurements of stage and discharge is represented using triangular fuzzy numbers, and their spread is determined according to the International Organization for Standardization (ISO) standard 748 guidelines. The extension principle based fuzzy arithmetic is used for the aggregation of various uncertainties into overall stage-discharge measurement uncertainty. In addition, a fuzzified form of ISO 748 formulation is used for the calculation of combined uncertainty and comparison with the fuzzy aggregation method. The methodology developed in this paper is illustrated with a case study of the Thompson River near Spences Bridge in British Columbia, Canada. The results of the case study show that the selection of number of velocity measurement points on a vertical is the largest source of uncertainty in discharge measurement. An increase in the number of velocity measurement points provides the most effective reduction in the overall uncertainty. The next most important source of uncertainty for the case study location is the number of verticals used for velocity measurements. The study also shows that fuzzy set theory provides a suitable methodology for the uncertainty analysis of stage-discharge measurements. [ABSTRACT FROM AUTHOR]

This paper evaluates the comparative and absolute in-plane seismic performance of rainscreen and nonrainscreen stucco exterior cladding systems for residential wood frame construction in British Columbia. In this study, an experimental program including quasi-static and dynamic tests was implemented, comprised of 18 (in-plane) quasi-static tests and two dynamic tests. The principal parameters investigated in this study were type of strapping, type and length of strapping fastener, and type and length of lath fastener. All rainscreen specimens were constructed with a 20 mm air space. The overall conclusion is that both rainscreen and nonrainscreen stucco comply with the code requirements addressing the permissible drifts. Therefore, both stucco systems were found to improve the structural behaviour when used as the lateral resisting system of residential wood frame buildings. This paper concludes with recommendations for seismic refinements to current construction practices. [ABSTRACT FROM AUTHOR]

Accident prediction models are invaluable tools that have many applications in road safety analysis. However, there are certain statistical issues related to accident modeling that either deserve further attention or have not been dealt with adequately in the road safety literature. This paper discusses and illustrates how to deal with two statistical issues related to modeling accidents using Poisson and negative binomial regression. The first issue is that of model building or deciding which explanatory variables to include in an accident prediction model. The study differentiates between applications for which it is advisable to avoid model over-fitting and other applications for which it is desirable to fit the model to the data as closely as possible. It then suggests procedures for developing parsimonious models, i.e., models that are not over-fitted, and best-fit models. The second issue discussed in the paper is that of outlier analysis. The study suggests a procedure for the identification and exclusion of extremely influential outliers from the development of Poisson and negative binomial regression models. The procedures suggested for model building and conducting outlier analysis are more straightforward to apply in the case of Poisson regression models because of an added complexity presented by the shape parameter of the negative binomial distribution. The paper, therefore, presents flowcharts detailing the application of the procedures when modeling is carried out using negative binomial regression. The described procedures are then applied in the development of negative binomial accident prediction models for the urban arterials of the cities of Vancouver and Richmond located in the province of British Columbia, Canada. [ABSTRACT FROM AUTHOR]

This paper presents a study describing the effect of various hydrological variables in stochastic dynamic programming (SDP) for solving the optimization problem of managing a hydropower system. We will show how choosing the best hydrological variables can strongly affect management policies. This is especially true for the system studied here, namely the Kemano hydroelectric system located in British Columbia, Canada, which is subject to large streamflow volumes due to significant snow cover during winter. Real-time snow water equivalent (SWE) data can be used directly as a variable in SDP management policies. Results indicate that for the system in this study, the maximum SWE (i.e., highest level of SWE observed from the start of winter to the current decision period) is the best among the methods investigated for effective, safe management, compared with Markov or order p autoregressive models when forecasts are not available. [ABSTRACT FROM AUTHOR]

Expansion and densification of urbanized areas can lead to increased pressure on an area's water and wastewater infrastructure. This paper presents an optimization model using geographic information systems to locate potential sources and sinks of reclaimed water within an urbanized area. A mathematical solver then maximizes the water reuse using a set of constraints on mass balance, water quality, and electricity used for pumping. Three variations of the model are applied to Vancouver, British Columbia. The first scenario identifies a number of potential industrial sources and sinks for direct cascading with a total potential water savings of 133 400 m3/year. With the implementation of a satellite water reclamation facility in scenario 2, water recycling potential is increased to a maximum of 613 800 m3/year. Scenario 3 expands to include the non-industrial water users and the potential for water reuse is increased to a maximum of 969 200 m3/year. [ABSTRACT FROM AUTHOR]

This paper describes a study of the seismic behaviour of taller eccentrically braced frames (EBFs). Chevron-type EBFs with shear-critical links are designed for 14-, 20-, and 25-storey buildings in Montreal and Vancouver. For each location the importance of different design criteria is discussed and an appropriate design sequence is proposed. It was found that ductility requirements did not control design. For Vancouver, buildings member selection was mostly influenced by the inelastic inter-storey drift requirements whereas for Montreal ensuring the global frame stability was critical. The seismic response of these frames to the sets of earthquake records calibrated to match design spectra is described. The seismic performance for Vancouver frames was found to be adequate, except that in the upper storeys the inelastic link deformations and shear forces exceeded values anticipated in design. For the Montreal structures, all global and local response indicators remained well below the design limits. [ABSTRACT FROM AUTHOR]

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 compared with those obtained from the tests conducted on conventional single-family wood-frame houses as part of the Earthquake 99 (EQ-99) Woodframe House Project at The University of British Columbia. The seismic performance of the CWD was superior to that of the nonengineered housing system and comparable to that of the engineered wood-frame housing system. Le système de construction « Canadian Wooden Domes (CWD) » est un système modulaire novateur de construction sectionnelle, monolithique et orthotrope. Le cadre principal de ces structures est bâti en utilisant des éboutures qui sont normalement mises en copeaux ou utilisées pour des aboutages. La structure, par rapport à celle des maisons unifamiliales conventionnelles à ossature de bois, se fabrique rapidement et l’assemblage rapide sur le site tend à diminuer le temps de construction global. En tenant compte de ces avantages, une étude technique a été lancée pour examiner le rendement de cette structure unique de dôme en bois modulaire dans les zones sujettes aux séismes et sa résistance à une charge de neige abondante. Le présent article décrit les résultats d’une série d’essais en charge statique et dynamique effectués sur les dômes en bois dans le cadre de cette étude. En se basant sur le rendement structural de ces dômes en bois sous des charges statiques et dynamiques, les résultats indiquent généralement que les dômes en bois pourraient être une solution de remplacement au système traditionnel de construction à ossature de bois. Ces résultats ont ensuite été comparés à ceux obtenus lors d’essais effectués sur des maisons unifamiliales à ossature de bois traditionnelles dans le cadre du projet « Earthquake 99 Woodframe House Project » réalisé antérieurement à l’Université de la Colombie-Britannique. Par rapport aux structures à ossature de bois traditionnellement mises à l’épreuve, le dôme en bois présentait un rendement sismique supérieur à celui des systèmes non techniques et un rendement sismique similaire à celui des systèmes techniques à ossature de bois. [ABSTRACT FROM AUTHOR]

This paper presents a comparison of the two main regional damage estimation methodologies currently in use, namely the modified Mercalli intensity (MMI) based approach and the spectral parameter based approach. In the first methodology, expected damage is related to ground shaking intensity in terms of MMI through damage probability matrices. In the second methodology, the ground motion intensity is described in terms of spectral acceleration (SA), and building response in terms of spectral displacement (SD). Both methodologies were applied to buildings in Vancouver of three different construction types: single-family wood-frame houses, low-rise unreinforced masonry buildings, and high-rise concrete frame structures with concrete shear walls. The two methodologies predict damage that lies in the same general damage categories of light and moderate, which are defined by fairly broad ranges in mean damage factors. The specific mean damage factors predicted by the two methods for a given location are significantly different, however. The significant differences in mean damage factors imply significant differences in damage costs and hence in seismic risk. [ABSTRACT FROM AUTHOR]

This paper presents the results of regional seismic risk assessment studies that were carried out for two cities in southwestern British Columbia, Vancouver and Victoria. Ground shaking intensity in the area was obtained using the seismic source zones delineated by the Geological Survey of Canada for a probability level of 10% chance of exceedance in 50 years. Building inventories were compiled by aggregating data from sidewalk surveys as well as municipal databases. Modified Mercalli intensity-based damage matrices that relate the level of ground shaking to the amount of damage expected in different types of structures were used to estimate damage to structural and non-structural components of buildings. Estimated damage and loss distributions were mapped on a block-by-block basis. The historic sections of the cities were estimated to have damage levels between 10% and 30% of the replacement cost, while in the rest of the cities the estimated damage was generally in the 5% to 10% range. The results show the estimated economic loss distribution is considerably different from the damage distribution. Although the older neighbourhoods of the cities are expected to suffer highest amount of damage, the highest amount of economic loss is estimated to occur in areas with concentration of concrete high-rise buildings. [ABSTRACT FROM AUTHOR]