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The collaborative federal–provincial Southern Indian Lake project in north-central Manitoba covered an area of more than 3500 km2 of the Trans-Hudson orogen. Regional-scale geological mapping, sampling, and lithogeochemical, isotopic, and geochronological studies resulted in the identification of distinct assemblages of supracrustal rocks and varied episodes of plutonism. A granodiorite gneiss dated at ca. 2520 Ma is interpreted to represent the basement of the Southern Indian domain and is considered a separate crustal domain, named the Partridge Breast block. The Churchill River assemblage is composed of juvenile pillow basalt with intervening clastic sedimentary rocks, possibly a reflection of plume magmatism related to initial rifting of the Hearne craton margin. The Pukatawakan Bay assemblage consists mainly of massive to pillowed, juvenile metabasaltic rocks and associated basinal metasedimentary rocks. The Partridge Breast Lake assemblage is dominated by continental-arc volcanic and volcaniclastic rocks associated with basinal metasedimentary rocks. The Strawberry Island assemblage, consisting of arenite and polymictic conglomerate, is interpreted to have been deposited in a foreland-basin basin or intra-orogen pull-apart basin environment. The Whyme Bay assemblage is characterized by fluvial-alluvial orogenic sediments and is temporally linked to the Sickle Group rocks in the Lynn Lake greenstone belt. Granitoid rocks, dominantly monzogranite and granodiorite, range in age from ca. 1890 to 1830 Ma and occur throughout the Southern Indian domain, and intermediate and mafic intrusions of similar ages are also present. In this paper, we integrate these new data into a tectonic framework for the Southern Indian domain of the Trans-Hudson orogen in Manitoba. [ABSTRACT FROM AUTHOR]

Landslides are a risk to buried gas pipeline infrastructure, but these risks are particularly difficult to assess given the complex nature of landslide movements. This paper presents of portion of research conducted at the University of Manitoba where gas pipelines within active landslide areas were monitored over a 4 year period. Two locations were examined in western Manitoba within the Assiniboine River Valley where a shallow natural gas pipeline runs parallel to the valley slope. A field investigation and monitoring program was undertaken where surficial ground movements and soil and pipe temperatures and pipe strains through strain gauges were measured. Monitoring results identified soil near the pipeline does not freeze, and ground movements are <50 mm/year. The monitoring results also showed pipe stresses and behaviour were affected by backfilling, thermal changes, soil−pipe relaxation, and ground movements. An unexpected outcome of the research was the response of the pipeline to slight ground movements was easily captured by the strain gauges and these movements, slow or surges, tended to occur at the same time between the two sites suggesting movements occur due to regional environmental effects. [ABSTRACT FROM AUTHOR]

Three highway bridges in the Canadian province of Manitoba are being monitored continuously not only for their long-term performance but also for bridge weighing-in-motion (BWIM). Data collected for the BWIM study has led to some observations that have far-reaching consequences about the design and evaluation loads for highway bridges. This paper presents the well-known concept of equivalent base length, Bm, as a useful tool for comparing trucks with different axle weight and spacing configurations as they influence load effects in all bridges. It is discussed that the statistics of gross vehicle weights (GVWs), W, collected over a one-month period is not significantly different from that for the GVW data collected over a longer period. A rational method concludes that the value of W for the CL-W Truck, the design live load specified by the Canadian Highway Bridge Design Code, is 555 kN for Manitoba. The observed truck data in Manitoba presented on the W–Bm space is found to be similar to that collected in the Canadian province of Ontario more than four decades ago. It was also found that the multi-presence factors, accounting for the presence of side-by-side trucks in two-lane bridges, specified in North American bridge design and evaluation codes are somewhat conservative. [ABSTRACT FROM AUTHOR]

There are a myriad of laws, regulations, and policies governing the operating weights and dimensions of trucks. In Canada and many northern states, these regulations form a continuum of basic limits, seasonal variations, and overweight/overdimension limits that are legally permitted. This paper deals with the seasonal aspects of weight limits (winter weight premiums and spring weight restrictions) governing trucking within and to and from the prairie region. This region encompasses Manitoba, Saskatchewan, and Alberta, and the northern tier states of Minnesota, North Dakota, and Montana. The paper presents results of research conducted for the transportation departments of the three prairie provinces and Public Works and Government Services Canada. It discusses existing winter weight premium and spring weight restriction regulations, as well as basic weight regulations in the region, and their technical rationale. It examines possibilities for using advanced technologies to help harmonize and rationalize seasonal truck size and weight regulations and enforcement practices, and identifies immediate opportunities for rationalization and harmonization of spring weight restrictions and winter weight premiums. [ABSTRACT FROM AUTHOR]

The Thompson Nickel Belt marks the boundary between the Archean Superior Province and the Trans-Hudson Orogen in Canada. It comprises Archean gneisses, and Paleoproterozoic rocks with metasediments and metavolcanites (Ospwagan Group) and intrusions. The gneisses are frequently migmatitic and host numerous pegmatites. The western belt boundary is a fault contact with the Kisseynew Domain of the Reindeer Zone. In the south, the transition zone between the belt and the Kisseynew Domain comprises granitoids and a detrital sequence (Grass River Group), part of which grades into turbidites in the Kisseynew Domain. The eastern belt boundary is a diffuse zone where the Archean east-west (E-W) structural trend changes into the north-northeast (NNE) trend of the belt. This paper presents U-Pb ages for granitoids and 207Pb/206Pb detrital zircon ages from the Ospwagan and Grass River groups. Ages and a comparison of events in the belt and in the eastern Reindeer Zone have major implications. The change from stable platform deposits to syn-tectonic filling and emplacement of mafic intrusions in the Ospwagan Group are attributed to the convergence between the Reindeer Zone and the Superior Province at 1891-1885 Ma. At ca. 1850 Ma, continuing convergence led to drowning of marginal basins of the Superior craton and to the development of a transpressive regime in the belt, the onset of which could be as old as ca. 1885 Ma. Metamorphic ages of 1818-1785 record closure of the Kisseynew basin and crustal thickening. Collision of the new continental block with the Superior Province was accommodated by transpression until 1750-1720 Ma. La ceinture de Thompson est située entre le Craton archéen du Supérieur et l'orogène paléoprotérozoïque du Trans-Hudson, au Canada. Elle comprend des gneiss archéens souvent migmatitiques, et des roches paléoprotéroïques, métasédiments et métavolcanites (Groupe Ospwagan), et intrusions. A l'ouest, une zone de faille marque le contact entre la ceinture et le domaine Kisseynew de la Zone de Reindeer. Vers le sud, cette zone de transition entre la ceinture et le domaine Kisseynew comprends des granitoïdes et une séquence détritique (Groupe Grass River), qui passe graduellement aux turbidites du domaine Kisseynew. Sur la bordure orientale de la ceinture, le grain structural E-W du Craton archéen se réoriente dans le grain NNE de la ceinture. Cet article présente des âges U-Pb pour différents granitoïdes et des âges 207Pb/206Pb pour les zircons détritiques des groupes Ospwagan et Grass River. Les âges et une comparaison des événements affectant la ceinture et l'est de la zone Reindeer ont des implications importantes. Dans le groupe Ospwagan, le passage de dépôts de type plate-forme à des dépôts syn-tectoniques, et l'intrusion de roches basiques, sont attribuées à la convergence entre la zone Reindeer et le Craton du Supérieur vers 1891-1885 Ma. Vers 1850 Ma, la convergence conduit à l'enfouissement des bassins de la marge du Craton et à un régime transpressif pouvant avoir débuté dès ca. 1885 Ma. La fermeture du bassin de Kisseynew et l'épaississement crustal sont enregistrés par des âges de métamorphisme entre 1818 et 1785 Ma. Le régime transpressif se poursuit jusqu'à ca. 1750-1720 Ma. [ABSTRACT FROM AUTHOR]

The major rivers within the City of Winnipeg are founded in glacial Lake Agassiz clay and silt sediments that have low shear strength. As such, riverbank instabilities are a common issue along many stretches of the rivers. The use of rockfill columns has become an increasingly utilized approach for stabilizing failing banks. Recent cases in Winnipeg have shown that movements can occur following installation of rockfill columns. Uncertainty regarding the magnitude of these movements that is required to mobilize shearing resistance in the rockfill columns has resulted in situations where the stability of riverbanks following remediation has been questioned. This has provided a need to improve our understanding about how much movement a stabilized slope must undergo before sufficient shear resistance of the rockfill column will be mobilized. The results of experimental testing conducted to assess the shear mobilization of rockfill column materials using a large-scale direct shear test apparatus are presented in this paper. The testing methodology is described along with the test results. The results show that the development of material specifications, construction, and placement methods and appropriate methods of analysis requires understanding of the stress–strain properties of the in situ soil and the rockfill material. [ABSTRACT FROM AUTHOR]

All wood utility poles require an effective maintenance program to ensure safe and reliable service. The end of a wood utility pole's useful life can be attributed to several factors, including decay, mechanical damage, weathering, and changing design requirements. Pole life can be extended through an effective preservative treatment and maintenance program, but all poles will reach a point when they are no longer suitable for their intended use. With the increasing cost of quality wood for use in poles, along with environmental concerns regarding pole disposal and chemical treatment of existing poles, new innovative methods are required to restore and maintain the structural integrity of existing wood poles. This paper presents results from a research program carried out at the University of Manitoba to develop a repair and rehabilitation technique for wood poles using fibre-reinforced polymers (FRP). [ABSTRACT FROM AUTHOR]

Groundwater from the Carbonate Rock Aquifer is extensively used for cooling purposes in Winnipeg, Manitoba. This paper examines the factors affecting the magnitude and timing of temperature increases at production wells in groundwater-source cooling applications through numerical modeling and observations at a case study site. Generic simulations carried out using typical hydrogeologic parameters for the Carbonate Rock Aquifer suggested that temperature increases of a few degrees occur at a typical production well only a few years after the start of operation in a given system. Spacing of the wells and pumping rates were found to have a greater affect than material properties in a homogeneous aquifer. A case study of a thermal doublet in the Winnipeg area indicated, however, that heterogeneities are capable of causing a departure from the predicted temperatures of the generic models. The case study showed that it is possible to make reasonable predictions of the behaviour of the subsurface temperature field during thermal development of the Carbonate Rock Aquifer. Temperature records of the length used in this study will not be available in new developments, however, and efforts must be made to conduct more extensive field investigations to ensure that designs can properly account for geologic conditions. [ABSTRACT FROM AUTHOR]

Lithoprobe's sponsorship has led to the acquisition of paleomagnetic data from ~20 units throughout the Paleoproterozoic Trans-Hudson Orogen (THO) of Saskatchewan and Manitoba, essentially the first such data for the region. Discussed summarily in this paper, they provide an initial framework for the THO's tectonic evolution. They show that the Archean Hearne and Superior cratons were at subtropical and subpolar paleolatitudes, respectively, at ~1875 Ma, with the Lynn Lake – LaRonge arc midway between them in the Manikewan Ocean. By ~1855 Ma, this ocean was still ~5500 ± 700 km wide, and its seafloor was subducting northwestward under the Hearne craton and pericratonic Peter Lake domain margin with the coeval development of an Andean-type continental magmatic arc, the Wathaman–Chipewyan batholith. Between ~1855 and ~1810 Ma, coalescing apparent polar wander path (APWP) segments record closing of the ocean at a rate of ~12 cm/a, trapping and accreting the several separate intervening terranes (Flin Flon, Hanson Lake, Lynn Lake – LaRonge, Rottenstone, and presumably also other THO terranes). From ~1815 to ~1775 Ma, the assembled terranes drifted as a coherent craton, yielding a stillstand and hairpin in the APWP. [ABSTRACT FROM AUTHOR]

Although bridges were among the first civil engineering structures to use structural health monitoring (SHM) technologies, research is now expanding to explore other types of applications, including Manitoba's famous Golden Boy statue. Global research is identifying the value of using SHM technologies for civil engineering applications. Structural health monitoring uses a variety of sensors to gather information about the behaviour of a structure. The information creates a valuable knowledge base that can be analyzed to help identify potential structural risks, develop safer and more efficient new structures, and determine more effective ways to rehabilitate existing structures. This paper briefly describes the history of the Manitoba Legislative Building and the Golden Boy and also the use of SHM technologies to help preserve the Golden Boy statue, an icon of provincial heritage. [ABSTRACT FROM AUTHOR]