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This paper presents an experimental program to justify the barrier design at the barrier-deck junction when compared to the factored applied transverse vehicular loading specified in the Canadian Highway Bridge Design Code (CHBDC). Compared to the dimensioning and the glass fibre reinforced polymer (GFRP) bar detailing of a recently crash-tested GFRP-reinforced barrier, the adopted barrier configurations in this paper were similar to those specified by Ministry of Transportation of Québec (MTQ) for TL-5 barrier except that the base of the barrier was 40 mm narrower and the deck slab is of 200 mm thickness, leading to reduction in the GFRP embedment depth into the deck slab. Four full-scale TL-5 barrier specimens were tested to collapse. Correlation between the experimental findings and the factored applied moments from CHBDC equivalent vehicle impact forces resulting from the finite-element modelling of the barrier-deck system was conducted followed by recommendations for use of the proposed design in highway bridges in Québec. [ABSTRACT FROM AUTHOR]

There is evidence that extreme ice loads combined with moderately high winds may cause catastrophic damage to overhead power lines and prolonged periods of electrical power outage. In this paper, a probabilistic model for combined wind and ice loads was developed for establishing realistic and conservative criteria for design and normalization. The proposed model combines icing of extreme thickness with a moderate wind speed, Vice, reduced by a reduction factor, kr, with respect to the extreme wind speed, Vmax. The evaluation of kr, which is the main purpose of this paper, is done by means of statistical analysis of samples taken from the same initial distribution of hourly wind speeds, Vh. The size of samples corresponds to the average annual icing persistency period, Tipp, observed in the climatic conditions of Quebec. This period, which was established in an earlier study by the authors using statistical analysis of data from the Hydro-Québec passive ice meter (PIM) network, is evaluated to be on average 144 h/year. It was found that kr ranges from 0.4 to 0.7, mainly as a function of the coefficient of variation (COV) of the initial distribution of wind speeds and the return period prescribed for extreme climatic loads. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to describe the characteristics of brash ice in the St. Lawrence River downstream of Montréal over a period of three winters. We used two instruments deployed in the St. Lawrence River navigation channel through Lake St. Pierre to measure ice parameters: an acoustic Doppler current profiler (ADCP) and an ice-profiling sonar (IPS). This paper discusses the capacities of these instruments to quantify ice characteristics and to predict the risk of ice congestion. It was found that wind velocity and air temperature play major roles in the variation in ice parameters and, consequently, in the occurrence of ice congestion in the navigation channel through Lake St. Pierre. Comparison of the IPS and ADCP data showed good agreement and demonstrated that these two instruments can be very effective for certain ice applications. [ABSTRACT FROM AUTHOR]

The poor seismic performance of schools has made their assessment and retrofit a priority in moderate and high seismic zones. Given the large building inventory to evaluate, rapid seismic screening methods are often implemented to prioritize detailed interventions. This paper describes schools' specific characteristics to be considered when applying these procedures, and shows how the FEMA154 approach can be modified to consider them. The adapted method is a score assignment procedure based on the following six essential characteristics: seismicity, lateral load resisting system, construction year, potential structural weaknesses (or irregularities), potential for pounding of adjacent buildings, and local soil conditions. The method is illustrated with case studies, applied to 101 school buildings in Quebec. Results show that most of the parameters considered influence the final scores. In particular, the treatment of structural weaknesses and potential for pounding proved effective in differentiating the likely seismic performance of the buildings. [ABSTRACT FROM AUTHOR]

Sewer deterioration, prevalent in municipalities throughout Canada, prompted the Quebec provincial government to implement a 1% renewal rate of the conduit facilities as to meet the goals of the national water plan adopted in 2002. Some of the most affected municipalities are usually the ones already under tight budget constraints, and cannot therefore afford the use of CCTV inspections in assessing the state of their sewage systems. This paper proposes a probabilistic model devised to survey the current conduit deterioration state caused by maintenance and operational conditions. Based on the multinomial logistic regression, this model - successfully applied to a case study in Quebec - shows the temporal deterioration of conduits for different material types. On average, it correctly predicted 54% of outcomes for transition probabilities involving both condition classes 1 (excellent) and 2 (good), and it showed a 59% correct prediction for class 3 condition (fair). This model is a recommended tool - applicable in combination with current exploratory techniques - for an effective prevention of conduits failure. [ABSTRACT FROM AUTHOR]

This paper examines the problem of finding an optimal operating policy for Hydro-Quebec's Manicouagan River and Outardes River hydroelectric installations. The solution method is based on the sampling dynamic programming (SSDP) algorithm. We use a new hydrologic state variable to capture the inflows regime, and this variable is given by a linear combination of the snow water equivalent and soil moisture. In real-time operation, this variable is calculated by a hydrologic model and incorporated in the operating policy to calculate the water released at each power plant. The algorithm is compared to the lag-1 stochastic dynamic programming (SDP) already implemented at Hydro-Québec, through a statistical analysis with a set of 40 synthetic historical inflow scenarios obtained by hydrologic modeling, using synthetic temperature and precipitation produced by a stochastic weather generator. The results of the analysis show that the SSDP operating policy is statistically superior to the operating policy of the lag-1 SDP model. The SSDP operating policy does not underestimate the volume of runoff occurring during the spring season contrary to SDP. Consequently, there is a reduction in the hm3 of water spilled, while the average annual generation is increased. [ABSTRACT FROM AUTHOR]

This paper presents the results of an exploratory analysis of falling weight deflectometer (FWD) data collected on a large project about the spring thaw behaviour of pavements. The test site includes four test sections, two of which are conventional flexible pavement structures, whereas the other two are built with a cement-treated base. The aim of this study is to verify the applicability of using FWD time history data to evaluate damage to a road during the thawing period. The applicability of the analysis techniques is verified through the phase angle and dissipated energy. The data analyzed were obtained from tests conducted with an FWD on one flexible pavement test section. The results obtained showed a clear difference between the winter, thawing, and summer periods. It was found that the phase angle and dissipated energy can be used to evaluate the road damage during the thawing period through quantification of the phase angle and dissipated energy. These factors can also be used to describe the pavement behaviour in terms of elasticity and viscoelasticity. Cet article présente les résultats d'une analyse exploratoire de données de déflectomètre à masse tombante (FWD) colligées lors d'un grand projet sur le comportement des chaussées lors du dégel du printemps. Le site d'essai comprend quatre sections : deux ont des structures conventionnelles de chaussée flexible et les deux autres sont construites sur une fondation traitée au ciment. L'objectif de l'étude est de vérifier l'applicabilité des données historiques FWD pour évaluer le dommage à la route durant la période de dégel. L'applicabilité des techniques d'analyse est vérifiée par l'angle de phase et l'énergie dissipée. Les données analysées ont été obtenues lors d'essais réalisés avec le déflectomètre à masse tombante sur une section d'essai de chaussé flexible. Les résultats montrent une différence évidente entre les périodes d'hiver, de dégel et d'été. Il s'est avéré que l'angle de phase et l'énergie dissipée peuvent être utilisés pour évaluer les dommages à la route durant la période de dégel en quantifiant l'angle de phase et l'énergie dissipée et en décrivant le comportement de la chaussée en termes d'élasticité et de viscoélasticité. [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]

This paper presents the construction details, field testing, and analytical results of six innovative concrete bridges reinforced with fibre-reinforced-polymer (FRP) bars recently constructed in North America, namely Wotton, Magog, Cookshire-Eaton, Val-Alain, and Melbourne bridges in Quebec, Canada, and Morristown bridge in Vermont, USA. All six bridges are girder type, with main girders made of either steel or prestressed concrete. The main girders are supported over spans ranging from 26.2 to 50.0 m. The deck is a 200–230 mm thick concrete slab continuous over spans of 2.30–3.15 m. Different types of glass- and carbon-FRP reinforcing bars and conventional steel were used as reinforcement for the concrete deck slab. The six bridges are located on different highway categories, which means different traffic volume and environmental conditions. The bridges are well instrumented at critical locations for internal temperature and strain data collection using fibre optic sensors. These sensors are used to monitor the deck behaviour from the time of construction to several years after the completion of construction. The bridges were tested for service performance using calibrated truckloads. In parallel, a finite element analysis (FEA) was conducted and verified against the results of the field load tests. The FEA was then used to run parametric studies to investigate the effect of several important parameters such as FRP reinforcement type and ratio on the service and ultimate behaviour of these bridge decks. The analytical and field results under real service conditions, in terms of deflections, cracking, and strains in reinforcement and concrete, were comparable to those of concrete bridge deck slabs reinforced with steel. [ABSTRACT FROM AUTHOR]

Safe dam design, especially when the dam is likely to erode when submerged, must take into account wave surge. The lack of data for small structures built in a forest environment is a problem when assessing this surge. This paper proposes an approach to assess wave surge for these structures. The proposed approach is based on relationships developed by Saville et al. (1962) for inland lakes. An example to illustrate the application of this approach is discussed in the framework of the Quebec Dam Safety Regulation (Quebec Government 2002). [ABSTRACT FROM AUTHOR]

The paper presents research conducted following an investigation carried out by the Quebec Ministry of Transportation's Roadwork Service on the effects of tire width. The study looked at the impact of tires on the surface layer of pavement and the pavement behaviour as a result of this impact. The strains at a depth of 25 mm in the pavement, at the base of the pavement, and at the top of the subgrade were measured. Measurements were taken over two seasons representative of conditions prevailing in Quebec, in spring and in summer. Three parameters, the type of tire, the inflation pressure of the tire, and finally the load, were varied. The amplitude of damage produced by the circulation of a vehicle was then quantified to evaluate and compare the overall impact of various types of tires on pavement according to the various configurations. [ABSTRACT FROM AUTHOR]