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Kim I.-A.,University of British Columbia | Trosper R.L.,University of British Columbia | Trosper R.L.,University of Arizona | Mohs G.,Stsailes | Mohs G.,EBA Engineering Consultants Ltd
Forest Policy and Economics | Year: 2012

We have identified cultural uses of non-timber forest products (NTFPs) in the Sts'ailes, a group within the central Coast Salish First Nation in British Columbia, Canada. The non-timber forest products are culturally important and often accessible to local people. We undertook a community-based participatory case study of the cultural uses of non-timber forest products within the Sts'ailes traditional territory. We used semi-structured interviews, ethnography, and secondary documents (e.g. maps and supporting documents) to provide in-depth understanding of the NTFP uses. Sts'ailes people use NTFPs by (1) gathering plants for food and medicine, (2) making materials from the plants, (3) making spiritual regalia and paints for winter ceremonials, and (4) brushing with cedar branches as spiritual practices. Forest environments and NTFPs provide secured environment for spiritual bathing and other spiritual practices and cedar branches are essential to use for purification. Because of these uses, Canadian governments need to consult and accommodate the Sts'ailes people when undertaking forestry operations. In addition, Sts'ailes use of the land demonstrates their continued possession of it. © 2012 Elsevier B.V. Source

Khalili A.,EBA Engineering Consultants Ltd | Wijewickreme D.,University of British Columbia | Ward Wilson G.,University of British Columbia
Canadian Geotechnical Journal | Year: 2010

The idea of mixing mine tailings and waste rock to form "paste rock" prior to disposal is now receiving significant attention from the point of view of sustainable mine waste management practices. This approach has been viewed as a favourable alternative to traditional methods of mine waste disposal because paste rock has the potential to overcome deficiencies (e.g., acid rock drainage and liquefaction-induced failures) associated with traditional methods. To advance the current limited knowledge, a laboratory research program was undertaken to study the mechanical response of paste rock. Testing was undertaken on paste rock specimens prepared so that the tailings would "just fill" the void spaces within the waste rock particle skeleton. The findings suggest that the material is unlikely to experience flow deformation under monotonic shear loading conditions, at least up to the tested initial effective confining stress conditions of 400 kPa. The monotonic shear response of paste rock was found to be similar to that of rock-only material; this finding is in agreement with previous observations from one-dimensional consolidation testing where it had been shown that the rock particle skeleton would carry almost 90% of the externally applied stress on a given paste rock mass. Source

Barua U.,EBA Engineering Consultants Ltd | Azad A.K.,University of Calgary | Tay R.,University of Calgary
Transportation Research Record | Year: 2010

Intersections are recognized as the most hazardous locations on roads since conflict possibilities are high at intersections and often result in a high frequency of fatal crashes. A significant share of fatal crashes in Canada occur at intersections on rural undivided highways. Nevertheless, few studies have examined the factors contributing to the fatality risk of intersection crashes in Canada. In this study, a logistic regression model was applied to a sample of crash data at intersections on the rural undivided highways of Alberta, Canada, to investigate 18 factors and 71 variables. Of the significant factors, the major ones affecting the likelihood of fatality are the type of intersection, horizontal and vertical alignment of the highway at the intersection, signalization at the intersection, type of collision, impairment of drivers, and age of drivers involved in crashes. The fatality risk of intersection crashes tends to increase when crashes occur at offset intersections or at cross or T-intersections on horizontal curves. The likelihood of fatality tends to increase if the intersection is on a sag curve or at a constant grade. However, signalization at intersections tends to reduce the likelihood of fatality. Pedestrian-involved collisions, head-on collisions, right-angle collisions, and run-off-road collisions that involve hitting a fixed object and overturning of vehicles are associated with higher fatality risk. An intersection crash also tends to have a higher likelihood of fatality when it involves an older driver (>70 years) or impaired (by alcohol or drugs) or fatigued drivers. Source

Taghaddos H.,University of Alberta | Soleymani H.R.,University of Alberta | Robson J.D.,EBA Engineering Consultants Ltd
ACI Materials Journal | Year: 2010

Most standardization agencies allow small-cylinder specimens (100 x 200 mm [4x8 in.]) to be used in compressive strength concrete testing. Some engineers are still skeptical about using small cylinders, however, as they believe that compressive strength testing results from small cylinders are too varied. Limited studies have been conducted regarding the precision of small cylinders compared to precision studies for conventional cylinders (150 x 300 mm [6x12 in]). This paper describes the results of a comparative concrete testing program conducted by 15 laboratories in Edmonton, AB, Canada, over the past 10 years. This study attempted to develop within-laboratory (repeatability) and betweenlaboratory (reproducibility) precision indexes for small and conventional concrete specimens by analyzing more than 2700 compressive strength concrete testing data within a compressive strength range of 17 to 57 MPa (2500 to 8300 psi). Copyright © 2010, American Concrete Institute. All rights reserved,. Source

Czarnecki B.,EBA Engineering Consultants Ltd | Day R.L.,University of Calgary
Concrete under Severe Conditions: Environment and Loading - Proceedings of the 6th International Conference on Concrete under Severe Conditions, CONSEC'10 | Year: 2010

By definition, High Performance Concrete (HPC) contains one or more Supplementary Cementitious Materials (SCM) and hydraulic cement, has a low w/cm ratio, usually contains a superplasticizer, and almost invariably contains silica fume. The performance characteristics include long service life, dimensional stability, ease of placement, and load carrying capacity. In a majority of project specifications for HPC, the use of silica fume is made a requirement. The focus of this study was to determine if high quality/high performance concrete can be produced using available sources of aggregate and fly ash, without silica fume. The study shows that both fly ash concrete and silica fume concrete can satisfy high performance expectations and produce an extended service life. The impact of the quality of aggregates and SCMs as well as the consistency of commercially produced concrete mixes on the performance of concrete are assessed. © 2010 Taylor & Francis Group, London. Source

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