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Climate change is altering the dynamics of New Brunswick's forests. To mitigate the effects of climate change, it is crucial to account for future uncertainties in climate projections and natural disturbance trajectories when designing forestry practices. This paper presents the projected changes in key climatic drivers for New Brunswick's forests, examines the impacts of climate change on forest stand dynamics, and reviews adaptive silviculture tools for climate change adaptation. By 2071–2100, a projected 4–6 °C increase in mean annual temperature will lead to a 39%–77% rise in growing degree-days and a reduction in summer atmospheric water balance by 48–79 mm across New Brunswick. Foresters should anticipate a doubling of annual area burned, the northward migration of spruce budworm (Choristoneura fumiferana (Clemens)), and the introduction of novel insects and diseases. Forest simulation models project a severe decline in boreal tree species abundance, including a 50% decline in balsam fir (Abies balsamea (L.) Mill) and black spruce (Picea mariana (Mill.) Britton et al.), offset by an increase in temperate species, notably red maple (Acer rubrum L.; +200%) and American beech (Fagus grandifolia Ehrh; +135%). Forests in the highlands and lowlands ecoregions, with 40%–50% and 15%–30% spruce and balsam fir composition, respectively, are particularly vulnerable. To limit climate change effects on forest values, foresters must prioritize climate resiliency in their management plans. Strategies should ensure the steady provision of forest goods and services under changing climatic conditions. Forest thinning enhances stand productivity and resilience, while shelterwood and two-age harvest balances timber production with diversity. Clearcutting, despite drawbacks, establishes younger, more vigorous forests with higher carbon sequestration potential. Assisted migration offers promise in helping threatened tree species adapt. Climate change will have a significant impact on New Brunswick's forests, leading to changes in key climatic drivers, increased risks of disturbances, and a shift toward more temperate tree species. However, there are existing adaptation strategies available. It is crucial to consider future uncertainties when designing and evaluating forestry practices, as this is essential for mitigating the effects of climate change on forest values and ensuring the continued provision of forest goods and services over time. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of mix design factors on the thermal properties of Superpave asphalt concrete. The thermal properties were measured using a guarded testing device (k-alpha device) developed recently at the University of New Brunswick. Two aggregate types, three gradations (determined by the material retained on a 4.75 mm sieve), and four compaction levels (at 35, 70, 100, and 160 gyrations) were investigated. The aggregate was 12.5 mm maximum nominal size with PG58-34 asphalt binder used for all mixes. The findings show that the thermal conductivity of the asphalt concrete ranged from 1.7 to 2.1 W/m·K. The specific heat capacity varied with the aggregate source and ranged from 940 to 2000 J/kg·K. The thermal diffusivity was found to vary with aggregate source. The aggregate type was found to have the most significant effect on the thermal properties. The compaction level had an effect but not a statistically significant one. The range of thermal properties determined in this paper is comparable to that found in the literature. [ABSTRACT FROM AUTHOR]

Major ice jam floods occurred along the Saint John River at Perth-Andover, New Brunswick, in 1976,1987,1993, 2009, and 2012. These floods have been devastating and resulted in relocation or demolition of many buildings in affected areas of the community. The purpose of this paper is to review ice processes along the Saint John River from Grand Falls to Beechwood Dam and their relevance to the ice-related problems that have occurred in Perth-Andover. The HEC-RAS program was chosen for ice jam flood stage computations, and cross-sectional, roughness and flow information entered to create a model of the study reach. The model was calibrated using field data obtained on 31 March 2000 along an ice jam in the Perth-Andover area. Model applications resulted in stage-discharge relationships for ice jams of different lengths and locations within the study stretch (Beechwood Dam to Grand Falls). These relationships indicate that ice jams can cause flooding at Perth-Andover, even with moderate spring breakup flows. The variation of ice jamming potential along the study stretch, and its relation to reservoir bathymetry and slope, are discussed. The increase in the number and severity of ice jam floods that have affected Perth-Andover may have resulted from changes in infrastructure and climate that have occurred since the 1950s. Local ice problems are likely to be aggravated over the next few decades but tempered in the longer term if the climate continues to change according to current projections. [ABSTRACT FROM AUTHOR]

This paper proposes the use of multi-level Bayesian modeling for calibrating mechanistic model parameters from historical data while capturing reliability by estimating a desired confidence interval of the predictions. The model is capable of estimating the parameters from the observed data and expert criteria even in cases of missing data points. This approach allows rapid generation of several deterioration models without the need to partition the data into pavement families. It estimates posterior distributions for model coefficients and predicts values of the response for unobserved levels of the causal factors. A case study from the New Brunswick Department of Transportation is used to calibrate a simplified mechanistic pavement roughness progression model based on 6-year international roughness index (IRI) observations. The model incorporates the effects of pavement structural capacity in terms of deflection basin parameter (AREA) in place of the modified structural number, traffic loading (ESAL) and environmental factors. The results of the model showed that, as expected, chipseal roads have higher as built roughness and deteriorate faster than asphalt roads. Sensitivity analysis of the deterministic (the mean predictions) part of the model showed that in New Brunswick where traffic is relatively low the environment is the most important factor. Cet article propose l'utilisation du théorème de Bayes à niveaux multiples pour étalonner les paramètres du modèle mécaniste à partir de données historiques, tout en obtenant une idée de la fiabilité par l'estimation d'un intervalle de confiance désiré des prévisions. Le modèle peut estimer les paramètres à partir des données observées et des critères experts, même dans les cas où des données sont manquantes. Cette approche permet de générer plusieurs modèles de détérioration sans avoir à répartir les données en classes de revêtement. Elle estime les distributions a posteriori des coefficients des modèles et prédit des valeurs de la réponse pour des niveaux latents de facteurs de causalité. Une étude de cas du ministère des Transports du Nouveau-Brunswick est utilisée pour étalonner un modèle mécaniste simplifié de progression de la rugosité des chaussées basé sur des observations de l'IRI sur six ans. Le modèle incorpore les effets de la capacité structurale des chaussées en termes de paramètre de la cuvette de déflexion (AREA), au lieu du nombre structural modifié, du volume de trafic (ESAL) et des facteurs environnementaux. Les résultats du modèle indiquent que les routes avec un revêtement d'usure présentent une rugosité établie au moment de la construction plus élevée et se détériorent plus rapidement que les routes en asphalte. typo in English faster that Une analyse de la sensibilité de la partie déterministe (les prévisions moyennes) du modèle indique qu'au Nouveau-Brunswick, là où le trafic est relativement faible, l'environnement est le facteur le plus important. [ABSTRACT FROM AUTHOR]

This paper describes results from a study on the dynamic behaviour of the Confederation Bridge due to seismic loads. For the purpose of the seismic analysis of the bridge, a finite element model was developed using three-dimensional (3D) beam elements. The model was calibrated using measured data of the bridge vibrations during a dynamic load test. Dynamic analyses were conducted by subjecting the model to selected seismic ground motions representative of the expected motions at the bridge location. The bending moments and displacements obtained from the analyses were used for the seismic evaluation of the bridge. It was found that the seismic effects considered in the design are appropriate for the required safety during the service life of the bridge. Cet article décrit les résultats d’une étude sur le comportement dynamique du Pont de la Confédération lors de charges sismiques. Un modèle par éléments finis utilisant des poutres tridimensionnelles a été développé aux fins de l’analyse sismique du pont. Le modèle a été étalonné en utilisant les données mesurées des vibrations du pont durant un test de charge sismique. Des analyses dynamiques ont été réalisées en soumettant le modèle à des mouvements sismiques du sol choisis représentant les mouvements prévus à l’emplacement du pont. Les moments de flexion et les déplacements obtenus des analyses ont été utilisés pout l’évaluation sismique du pont. Il a été conclu que les effets sismiques utilisés dans la conception sont appropriés pour le niveau de sécurité requis durant la vie du pont. [ABSTRACT FROM AUTHOR]

This paper describes results from a study of the dynamic performance of the Confederation Bridge during traffic load tests and a storm with high winds that occurred at the bridge site on 7 November 2001. The traffic load tests were conducted over a three-span segment of the bridge and consisted of single and double truck configurations at different speeds. The winds during the storm of 7 November 2001 were the strongest that have ever been measured at the bridge site since the opening of the bridge. The vibrations of the bridge during both the load tests and the storm were recorded by a network of 76 accelerometers. By processing the recorded vibrations, vertical deflections and dynamic amplification factors due to the traffic load tests and vertical and lateral deflections due to the wind during the storm were computed. The computed values were compared with those used in the design. It was found that both the deflections and the dynamic amplification factors were much smaller than the design values. [ABSTRACT FROM AUTHOR]