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Extensive research has been conducted on reliability-based design (RBD) for the ultimate limit state (ULS). Several RBD codes have been developed and implemented around the world that calibrate the ULS design for a target ULS reliability index (βuls). However, the serviceability limit-state (SLS) design still is considered using conventional deterministic approaches with an unknown SLS reliability index (βsls). This paper presents a relationship between βsls and the βuls that is specified already in the RBD codes. This relationship is linear, and a key variable in it is the ratio (R) of the SLS capacity (Qsls) to the ULS capacity (Quls). Both closed-form approximations and Monte Carlo simulations are used to characterize R probabilistically. For illustration, the relationship then is used to estimate βsls for augered cast-in-place piles designed in accordance with the RBD methodologies in the National Building Code of Canada. The results are highly dependent on the statistics of the limiting tolerable foundation settlement (ylt). For larger ylt values, the calculated βsls>βuls, which means that ULS designs automatically satisfy SLS criteria. For smaller ylt values, SLS criteria begin to control the design. The importance of sound ylt criteria is stressed. [ABSTRACT FROM AUTHOR]

Developing and constructing oil sand megaprojects are huge technological, engineering, and construction achievements for Alberta and Canada. Thousands of engineering and project management professionals and workers are contributing to the current effort with great pride and sense of satisfaction. But recent large capital oil sands construction projects have all experienced significant cost and schedule overruns. There are a number of reasons for these overruns. This paper provides a definition of a “megaproject,” illustrates the challenges in delivering oil sands megaprojects, and lists a number of reasons for cost and schedule overruns. [ABSTRACT FROM AUTHOR]

This note investigates different procedures to improve radar-based estimates of rainfall accumulation, using the City of Winnipeg, Canada, as an example. Specific contributions include the implementation assessment of an advection scheme to track the movement of storms, a scheme to account for wind-induced drift, and an attenuation correction scheme that includes a simple hail identification method. It was found that a combination of these schemes improved the correlation between gauge radar 10-min accumulations from 0.48 to 0.86 for six rainfall events that occurred in the summer of 2000 in Winnipeg. [ABSTRACT FROM AUTHOR]