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Effective winter road maintenance relies on precise road friction estimation. Machine learning (ML) models have shown significant promise in this; however, their inherent complexity makes understanding their inner workings challenging. This paper addresses this issue by conducting a comparative analysis of road friction estimation models using four ML methods, including regression tree, random forest, eXtreme Gradient Boosting (XGBoost), and support vector regression (SVR). We then employ the SHapley Additive exPlanations (SHAP) explainable artificial intelligence (AI) to enhance model interpretability. Our analysis on an Alberta dataset reveals that the XGBoost model performs best with an accuracy of 91.39%. The SHAP analysis illustrates the logical relationships between predictor features and friction within all three tree-based models, but it also uncovers inconsistencies within the SVR model, potentially attributed to insufficient feature interactions. Thus, this paper not only showcase the role of explainable AI in improving the ML interpretability of models for road friction estimation, but also provides practical insights that could improve winter road maintenance decisions. [ABSTRACT FROM AUTHOR]

Construction crew productivity is affected by the motivation of the crew performing given activities and by situational/contextual factors forming the dynamic construction environment. The literature lacks a comprehensive analysis of causal relationships between crew motivation and situational/contextual factors for dynamic modelling of crew productivity. The contributions of this paper are (1) identifying a set of criteria for performing expert weight assignment for heterogenous group experts in productivity research, (2) proposing an integrated fuzzy analytic hierarchy process–fuzzy decision-making trial and evaluation laboratory approach that provides a systematic, structured method for determining causal relationship mapping between factors affecting crew productivity, and (3) proposing an approach for identifying cause-and-effect groups among the situational/contextual factors and crew motivation, which can further be used to formulate strategic productivity improvement solutions. The proposed methodology is demonstrated using a case study on an actual industrial construction project in Alberta, Canada. [ABSTRACT FROM AUTHOR]

The selection of Architect/Engineer (A/E) is one of the critical decisions made by owners early in a project. Given that architects and engineers are not commodities; therefore, the assessment of A/E firms should be based on their qualifications. This paper attempts to quantitatively assess and understand the effects of A/E capabilities on project performance. To achieve this, a model was developed to identify the correlations between A/E consultant qualification, project characteristics, and project outcomes. Afterwards, it was validated using a prediction model developed using artificial neural networks implemented on a case study of 18 projects. This model connects the gap between the consultant procurement decision and its impact on the management performance and outcomes of a project. Furthermore, this paper offers an understanding of current procurement practices, as well as presenting the common evaluation criteria and their respective weights as adopted by several public owners in Alberta. [ABSTRACT FROM AUTHOR]

To facilitate more efficient winter maintenance decision support, road weather information systems (RWIS) have been widely used by highway agencies. However, the cost of RWIS stations is high, and they have limited monitoring coverage. To address this challenge, this paper presents an innovative framework that applies regression kriging to integrate stationary and mobile RWIS data to improve the accuracy of road surface temperature (RST) estimation. Furthermore, an optimal RWIS network expansion strategy is introduced by incorporating a modified particle swarm optimization method with the objective of minimizing spatially averaged kriging estimation errors. A sensitivity analysis is also conducted to investigate the influence of station densities on model performance. The case study from Alberta, Canada, demonstrates the feasibility and applicability of the proposed method. The findings provide insights for continuous monitoring and visualization of both road weather and surface conditions and for optimizing RWIS network planning. [ABSTRACT FROM AUTHOR]

Construction professionals agree that building information modelling (BIM) will revolutionize the architectural, engineering, and construction (AEC) industry and its impact will be felt by all project stakeholders including owners and facility managers. Statistics show that many owners and other stakeholders perceive BIM as a technology that can make project delivery more efficient because it allows project information to be fully integrated. In the future, owners are expected to demand the use of BIM to prevent over-budget and over-time project delivery. However, as we are preparing this contribution the level of implementation and use of BIM varies widely across the globe. This paper probes the state of BIM in Alberta from three points of view: ( i) the current understanding and implementation, ( ii) the motivations driving its use, and ( iii) the challenges hindering its implementation. The findings of this paper are extracted from individual responses to a web-based survey that was proposed to professionals in the Albertan AEC/FM industries. [ABSTRACT FROM AUTHOR]

This paper intends to establish a foundation that will permit an in-depth understanding of absenteeism in large-scale industrial construction. This type of construction currently suffers greatly from the negative impacts (e.g., productivity loss; cost and schedule overruns) of absenteeism. Taking into account the complexity of large-scale industrial construction (e.g., the long operational periods and the tremendous variety of trades and positions involved), a more systematic and comprehensive understanding of absenteeism is necessary. In an effort to address this issue, we developed a survey and an absenteeism tracking tool, both of which can be used in other industrial projects. To test their validity, a pilot project was established in an industrial multi-contractor enterprise in Alberta. The results of this project reveal the great potential of both the survey and tracking tool - it is evident that they can be applied to diverse industrial projects and enable an in-depth understanding of absenteeism. Further, the results have led to several findings (e.g., a significant amount of absences are not reported to supervisors in advance; the need to educate apprentices to avoid absences; and the fact that employees believe that fellow employees are more likely to be absent than themselves). The effects of different absence reduction and compensation policies currently practiced in industrial construction are also discussed in this paper. [ABSTRACT FROM AUTHOR]

A recent study on construction productivity improvement at the University of Calgary revealed the direct tool time (working time) of Alberta’s commercial construction to be about 51%. This study exposed inadequate communication and unavailability of required information as the main causes for a relatively lower tool time. Use of information technology (IT) to overcome widely visible communication issues was extremely limited at the construction site level. Construction companies’ hesitation to adopt new technologies was well noted whereas construction workers expressed their willingness and ability to use IT at the site level. The objective of this paper is to discuss the concept and the application of a novel communication tool (called an information booth) developed and pilot tested at a construction project. The concept and the technology presented in this paper have been tested at an actual construction project resulting in improvements in construction productivity, worker satisfaction, and efficiency. This paper also elaborates the rationale for a new technological framework (and the information booth), barriers for technology implementation, research objectives, methodology, and data analysis. [ABSTRACT FROM AUTHOR]

As the industrial construction sector in Alberta faces a period of megaprojects, cost and schedule overruns are becoming a major concern for both owners and contractors. One factor that often contributes significantly to these overruns is construction field rework. Despite the significance of rework, there are few industry standards available for defining, quantifying, and classifying field rework. This paper presents the results of a pilot study, conducted on one such megaproject, that attempts to develop a standard definition of construction field rework, a standard index for its quantification, and an approach for classifying the causes that lead to field rework so that they can be remedied. The data collection methodology developed is discussed, and the findings that arise from this methodology for the case study are presented. The main conclusion of this paper is that the proposed methodology is quite effective in its thorough analysis and treatment of the field rework issue, and it can be used as a first step towards an industry Best Practice for measuring and classifying construction field rework. It can now be used on subsequent projects over time to collect a sufficient dataset, from which the construction industry can develop industry standards and statistics on construction field rework. [ABSTRACT FROM AUTHOR]

Interface management (IM) is one of the major keys for construction project success. The severity of interface problems for different projects does not only delay the project, but also impacts overall project performance. This paper is an extension of a previous work that defined major IM problems in Alberta's construction projects. This research study intended to investigate, identify, and classify interface problem factors in Alberta's construction projects. The study included four stages. The first stage was a comprehensive literature review, pilot studies and face-to-face interviews in industry. In the second phase, a web-page questionnaire was conducted with participants from industry. Based on that, in the last two phases, a factor analysis and Pearson's correlation matrix were applied on the collected data. The study identified six IM factors, namely: 'management', 'information, bidding and contracting', 'by-law and regulation', 'technical engineering and site issues', and 'other interface problems'. Finally, correlation between IM factors and different construction data was tested. The data analysis results provided a comprehensive view of the main causes behind IM conflicts in Alberta's construction industry. [ABSTRACT FROM AUTHOR]

This paper evaluates the dynamic flexural response of sandstone from the Paskapoo formation in Alberta. Sandstone prisms were subjected to quasi-static flexure as per ASTM while a drop-weight impact tester was employed to generate stress rates up to 108 kPa/s. Companion testing under quasi-static compression on sandstone cylinders helped establish baseline properties including the compressive strength, elastic modulus, and Poisson's ratio. It was found that the flexural strength and fracture toughness of Paskapoo sandstone obey stress rate sensitive models developed originally for concrete. However, the fracture toughness was more stress rate sensitive than its flexural strength. [ABSTRACT FROM AUTHOR]

Significant cost overruns and schedule delays on oil and gas projects in Alberta have been of great concern for many companies. The industry has indicated a need for public data to verify anecdotal conclusions that labor productivity is the root cause behind project performance problems. In this paper, a sample of 37 Alberta oil and gas projects was analyzed. The findings provided evidence that poor planning and inadequate project scope definition gave rise to project cost and schedule performance problems, while labor productivity is merely a proximate cause. High correlations are revealed between deficient project performance and factors such as low percent engineering completed before construction start, low estimation accuracy of field productivity rates, unit costs, crew sizes, and indirect costs. The results also emphasized a need to increase the level of implementation of best management practices to ameliorate the effects of the challenging project environments. [ABSTRACT FROM AUTHOR]

Advanced traveller information systems (ATIS) play a very vital role in improving traffic conditions on the roads, by providing information for drivers to assist them in making more informed travel decisions. Drivers' perceptions towards ATIS mostly define these responses. This paper examines how the use of and familiarity with different sources and media of real time traffic information updates may affect drivers' perceptions, thereby determining their responses to ATIS technology. The study employs a hybrid discrete choice model that considers interactions between latent perception and the sources of traffic information sought. Data used in this study was collected through a survey conducted among a sample of 500 commuters who use Highway 2 (Deerfoot Trail) in Calgary, Alberta, Canada. In the case of major delays due to accidents or construction on Highway 2, the City of Calgary is using 12 variable message signs (VMS) to divert drivers to alternative parallel arterials. The developed integrated discrete choice and conditional latent variable model clearly identifies an important link between the propensity to comply with VMS information and the use of other traffic information sources. One of the primary findings of this study is the existence of a significant correlation between radio traffic information, TV traffic information, and VMS displays. It was found that drivers who listen to radio traffic information or watch TV traffic channels are more likely to be compliant with VMS messages, in terms of route diversions and changes in trip destinations. [ABSTRACT FROM AUTHOR]

This paper reports on a laboratory investigation into the performance of a novel stacked drop manhole design where two identical rectangular manholes are stacked one beside the other but at different heights so that there is a drop in elevation from one to the other. The focus of the study was to estimate the energy dissipation that occurs in such stacked manholes during diverse inflow conditions. Flow regimes inside the structure were identified and the effectiveness of the design was assessed under variable inflow conditions. Total energy dissipation in the stacked manhole was found to range from about 50% to 90%, and the contribution of each manhole chamber to the overall energy dissipation was assessed. A relationship between water depths in the manhole chambers and the corresponding outflow conditions was established. In addition, an analysis of the flow patterns and flow regimes highlighted the relevant parameters involved in the mechanisms of energy dissipation. [ABSTRACT FROM AUTHOR]

Full-scale laboratory tests were carried out at the University of Alberta to investigate the post-wrinkling ultimate behavior of steel pipelines. The pipe specimens exhibited extreme ductile behavior and did not fail in fracture under monotonically increasing axisymmetric compressive axial loads and displacements. Fractures developed at the wrinkled region, however, when a wrinkled pipe specimen was subjected to cyclic strain reversals due to unloading and loading of primary loads. This paper presents test procedures, complete post-wrinkling behavior, fracture limit strain values, and fracture configurations obtained from full-scale tests on wrinkled pipe specimens under cyclic and monotonic axial loadings. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of all documented ice jam release events for the Athabasca River at Fort McMurray, Alberta. A review of the historical records indicates that release waves in excess of 3 m and propagation speeds of 4–5 m/s are not uncommon. Numerous occurrences of increases in wave speed and magnitude suggest that temporary stalling of ice runs may be a significant factor in release event propagation. Detailed measurements of ice jam release events in 2001–2003, including most notably a 4.3 m high release wave measured in 2002, provide unprecedented data describing ice jam release wave propagation and suggest that continued propagation of a portion of the release wave downstream of a reformed jam could be a significant factor in immediate re-release. [ABSTRACT FROM AUTHOR]

Spring breakup on northern rivers can result in ice jams that present severe flood risk to adjacent communities. Such events can occur extremely rapidly, leaving little or no advanced warning to residents. Fort McMurray, Alberta, is one such community, and at present no forecasting model exists for this site. Many of the previous studies regarding ice jam flood forecasting methods, in general, cite the lack of a comprehensive database as an obstacle to statistical modelling. This paper documents the development of an extensive database containing 106 variables, and covering the period from 1972 to 2004, that was created for ice jam forecasting on the Athabasca River. Through multiple linear regression analysis, equations were developed to model the maximum water level during spring breakup. The optimal model contained a combination of hydrological and meteorological data collected from early fall until the day before river ice breakup. The number of historical years of data, rather than the scope of variables, was found to be the major limitation in verifying the results presented in this study. [ABSTRACT FROM AUTHOR]

For decades, many researchers have reported the decline in construction productivity, but it is impossible to generalize the productivity problems due to issues such as geographical differences, weather changes, skill level differences in the labour force, and workload demand. There are currently approximately 160 000 construction workers in Alberta, and the value of ongoing and future projects in the oil and gas sector alone is over Can$200 billion. Because of the high demand and necessity for a comprehensive research study for Alberta to improve construction productivity, a 2 year study commenced with the collaboration of four eminent contractors to investigate human, management, and external issues. Under human issues, 101 construction workers in the carpentry trade were observed, interviewed, and surveyed by questionnaire. This paper discusses the research method, results, and recommendations of the productivity research specific to the human issues. These recommendations were communicated to the contractors for improving the human issues by developing and analyzing a new expectancy model considering construction workers' effort and performance and the tool times observed to mitigate the reasons for non-tool time. [ABSTRACT FROM AUTHOR]

This paper reviews the factors and criteria for the design of new and the retrofitting of existing dry detention ponds to enhance removal of total suspended solids (TSS) from stormwater. Detention time is discussed as the most important factor affecting TSS removal. Two-stage facilities and multi-level outlet design are important means of enhancing TSS removal in dry ponds. Two dry ponds within the city of Edmonton were selected to evaluate their TSS removal. The level of expected TSS removal is low owing to the relatively short detention times for both ponds. Methods for retrofitting the dry ponds to enhance TSS removal are discussed.Key words: dry pond, stormwater, TSS removal, detention time, retrofitting.Cet article passe en revue les facteurs et critères de conception de nouveaux étangs de rétention, et de modification de ceux déjà existants, avec pour but d'améliorer la capacité d'enlèvement des substances solides totales en suspension (SST) contenues dans les eaux de ruissellement. Le temps de rétention est examiné en tant que facteur principal affectant l'enlèvement des SST. Les installations à deux étages et la conception de sorties multi-niveaux sont des procédés importants qui améliorent l'enlèvement des SST dans les étangs. Deux étangs de la Ville d'Edmonton ont été sélectionnés et leur capacité de rétention a été évaluée. Le niveau d'enlèvement des SST escompté est bas compte-tenu des temps de rétention relativement courts de ces deux étangs. Les méthodes de modification des étangs visant à améliorer l'enlèvement des SST sont examinées.Mots clés : étang, eaux de ruissellement, enlèvement des SST, temps de rétention, réajustement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Field and laboratory measurements of the transport of the suspended sediment from the Athabasca River near Hinton, Alberta, Canada are described. The objective of these measurements was to examine the influence of pulp mill effluent entering the river from a nearby pulp mill on suspended sediment. The results of the field measurement showed that the effluent had significant impact on the transport of the sediment. Specifically, the effluent increased the deposition rates of the sediment and caused a substantial reduction of sediment concentrations in reaches downstream of the effluent outfall. The reduction in sediment concentrations and the concomitant sediment loads can only be attributed to the pulp mill effluent as there were no abrupt changes in the hydraulic characteristics of the river in the reach of interest. These observations were confirmed by laboratory experiments that were carried out using a rotating circular flume located at the National Water Research Institute in Burlington, Ontario, Canada. The findings of this study have implications for modelling suspended sediment transport in rivers receiving bleached pulp mill effluents. [ABSTRACT FROM AUTHOR]