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Saskatoon, Canada

Haichert R.,PSI Technologies Inc | Kelln R.,PSI Technologies Inc | Wandzura C.,University of Saskatchewan | Berthelot C.,PSI Technologies Inc | Guenther D.,City of Saskatoon
Transportation Research Record | Year: 2012

Challenges in finding high-quality sources of natural aggregate have led Saskatchewan, Canada, road agencies to explore alternative solutions to meet aggregate demands. The use of recycled materials, such as recycled portland cement concrete (PCC), though traditionally limited to low-quality applications such as subbase or backfill materials, shows promise as a technically viable solution that also offers economic and environmental advantages. In this study, mechanistic material testing was used to examine the effects of cement stabilization on traditional granular base and on two impact-crushed recycled PCC materials from different locations. The unstabilized PCC materials had substantially better mechanistic material properties than the unstabilized conventional granular base material; this result indicates that PCC materials could be suitable for use in high-quality applications, such as base course layers, rather than being limited to use in low-quality applications, such as utility and embankment fills. This study also showed that cement stabilization substantially improved the mechanistic properties of conventional granular base material, yet had a much less pronounced effect on the material properties of the PCC materials. This result may be attributable to poor absorption of the cement by the PCC or a lack of rehydration of the PCC. There was minimal variability in the mechanical behavior of the PCC specimens despite a difference in stockpile location. Both types of PCC material were processed and crushed with the same technique and equipment. Source

Johnson K.,AECOM Technology Corporation | Sexsmith C.,City of Saskatoon
Proceedings, Annual Conference - Canadian Society for Civil Engineering | Year: 2012

The Yukon and White Pass Railway was the first major civil engineering project in North America north of the 60th latitude. Constructed in 27 months from 1898 to 1900, this 176 kilometre narrow gauge railway carried thousands of prospectors and their supplies to the Klondike Gold Rush from the Pacific Ocean. The railway provided the first efficient transportation link from the Port of Skagway, Alaska over the coast mountain range into the interior of the Yukon, and opened up the Yukon Territory to significant development by providing a major all-season transportation link for the territory for over 80 years. The railway also had an important role in the construction of the Alaska Highway, and the transport of ore from the Yukon mines to southern markets. The narrow gauge Yukon and White Pass Railway climbs almost 873 metres from sea level at the Port of Skagway to the White Pass summit in a distance of only 32 kilometres. This steep grade over the coast mountains was constructed with manual labour; the main equipment, aside from blasting powder, consisted of picks and shovels. The railway construction was maintained during the severe working conditions of a sub-arctic winter, and necessitated the development of construction techniques for permafrost areas, as well as cold region construction logistics and management. Source

Berthelot C.,University of Saskatchewan | Haichert R.,PSI Technologies Inc | Podborochynski D.,University of Saskatchewan | Wandzura C.,University of Saskatchewan | And 2 more authors.
Transportation Research Record | Year: 2011

The City of Saskatoon, Saskatchewan, Canada, commissioned the "Green Street" Infrastructure Program to investigate the potential of using recycled reclaimed asphalt pavement (RAP) and portland cement concrete (PCC) rubble as structural road layers. This study validated the mechanistic materials characterization and structural design of a field test section constructed using recycled RAP and PCC materials in addition to in situ reclaimed and recycled road materials. This paper presents a summary case study of the Green Street test section on 8th Street in Saskatoon. The rehabilitation of 8th Street consisted of two pavement rehabilitation systems: one incorporated a drainage layer and the other did not. The rehabilitation of the right-turn lane included a drainage system incorporating City of Saskatoon offsite impact-crushed PCC rubble material. The entire right-hand-turn lane and sections of the median lane and the driving lane were rehabilitated by rotomixing hot-mix asphalt concrete (HMAC) and granular base layers and adding offsite impact-crushed RAP to top up the remixed base layer. The top 200 mm of this remixed base layer was stabilized with cement-emulsion. The entire 8th Street test section was surfaced with typical City of Saskatoon HMAC. When subjected to mechanistic triaxial frequency sweep characterization, both the cement-emulsion-stabilized in situ remix material (utilized as a black base course) and the HMAC surfacing materials showed good mechanistic structural material constitutive behavior. The stabilized in situ remix material yielded end-product mechanistic material behavior that exceeded that of the HMAC surfacing. Source

Berthelot C.,University of Saskatchewan | Haichert R.,PSI Technologies Inc | Podborochynski D.,University of Saskatchewan | Wandzura C.,University of Saskatchewan | And 3 more authors.
Transportation Research Record | Year: 2011

This research developed a mechanistic-based framework for recycling rubble materials into high-value-added engineered road structural materials for use in urban road rehabilitation. Scientific-based engineering methods were integrated with advanced materials processing, road construction, and nondestructive asset management techniques to explicitly quantify the benefits of recycled material systems using reclaimed asphalt pavement (RAP) and portland cement concrete (PCC) rubble generated within the city of Saskatoon, Saskatchewan, Canada. The ability to process RAP and PCC rubble to meet or exceed conventional granular aggregate specifications with minimal waste was demonstrated. It was found that RAP and PCC aggregates can exceed the mechanistic material constitutive properties of conventional city of Saskatoon granular base aggregates by at least 30%. The mechanistic material property value of unstabilized RAP and PCC was demonstrated in addition to the benefits of various cold stabilization systems using cement and emulsion. Recycled RAP was used as a black base layer and PCC was used as a subbase course or a drainage and stress-dissipation layer, or both, in rehabilitated road structures of nine "Green Street" test sections constructed in Saskatoon. These test sections met or exceeded target structural designs and were validated by using nondestructive heavy-weight deflectometer testing. The use of recycled RAP and PCC rubble materials for urban road rehabilitation had economic, social, environmental, and energy benefits for the city of Saskatoon. Recycled rubble materials were found to provide a technically viable and cost-effective solution for rehabilitating urban low-volume roads relative to conventional granular aggregates. Source

This study compares the performance of uncalibrated and calibrated Highway Safety Manual (HSM) safety performance functions (SPFs) with jurisdiction-specific SPFs. The first edition of the HSM includes a number of SPFs which can be used to identify collision-prone locations on a roadway network. The HSM recommends that these SPFs be calibrated to more accurately reflect a specific jurisdiction's unique roadway characteristics, driver behaviour, etc. and to produce better-fitting results. An alternative approach is the creation of jurisdiction-specific SPFs. This study used negative binomial regression and 5 years of collision data (2005-2009) from the City of Regina, Saskatchewan to develop a set of SPFs. Three intersection categories were investigated: 3-leg unsignalized, 4-leg unsignalized, and 3-and 4-leg signalized. The SPFs provided in the HSM were calibrated using the Regina data, and a set of calibration factors was produced. To compare the different SPFs and find the best-fitting SPFs for the study region, the study used statistical goodness-of-fit tests and cumulative residual plots. The jurisdiction-specific SPFs provided the best fit to the data, and would be the best SPFs for predicting collisions at 3-and 4-leg intersections in the City of Regina. Source

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