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Corrugated web plate girders (CWPGs) have grown in popularity in Canada in recent years because of their economic efficiency. Although research on the flexural performance of such members has increased in recent years, there are still additional advancements that can be made in their design, particularly in the calculation of lateral torsional buckling resistance. However, no research has been presented in Canada on this subject, and very minimal research has been published on CWPGs with sinusoidal corrugated webs. The purpose of this study was to examine the lateral torsional buckling strength of CWPGs with sinusoidal corrugated web profiles through experimental analysis of CWPGs that are currently being used in Canada. Nine simply supported specimens were loaded and failed in lateral torsional buckling (LTB). The nine specimens were chosen according to size in order to observe variations in LTB strength based on web thickness, web depth, and variations in identical beams. All beams tested recorded strengths far greater than conventional design strength, confirming the conservative nature of the current design procedure. As web thickness increased, a trend of ultimate capacity increasing was observed. The depth of the webs had no significant effect on LTB strength apart from what was gained by increasing the depth of the flanges. Based on the results, an equivalent web thickness equation is proposed for the purpose of calculating a more precise LTB resistance. A numerical analysis was run on a wide range of beam sizes and compared with the physical testing results. It was determined that the proposed equation effectively captured the physical testing results among more than just the tested beams. However, future work should further examine the reliability of the proposed equation by testing more specimens and/or using the finite-element method. [ABSTRACT FROM AUTHOR]

Extensive research has shown that properly detailed and closely spaced transverse reinforcement in reinforced concrete columns can ensure ductile behavior during earthquakes. However, in regions of high seismicity, detailing requirements can result in heavily congested sections; the use of self-consolidating concrete (SCC) can facilitate construction in these situations. Although extensive research exists on the axial load behavior of traditional concrete columns, only limited research exists on the behavior of columns constructed with SCC. Research over the past two decades has also shown that use of steel fiber-reinforced concrete (SFRC) can improve the strength and ductility of columns by delaying cover spalling and improving core confinement. Recent research has also shown that the combined use of SCC and steel fibers can ease problems associated with the workability of traditional fiber-reinforced concrete. This paper presents the results from an experimental program that was conducted to study the axial behavior of reinforced concrete columns constructed with SCC and SFRC. Full-scale columns having rectangular cross sections were tested under pure axial compressive loading. The columns were detailed with varying amounts of transverse reinforcement in accordance with the requirements of the Canadian Standards Association. The results confirm that increasing confinement with closely spaced transverse reinforcement in rectangular SCC columns results in improvements in behavior and ductility. In addition, the results demonstrate that the use of SFRC in rectangular columns results in improvements in performance and ductility. [ABSTRACT FROM AUTHOR]

The seismic performance of 15 continuous four-span bridges with different arrangements of column heights and diameters and designed using the 2006 Canadian Highway Bridge Design Code provisions were studied using incremental dynamic analysis (IDA). The seismic risk associated with exceeding different damage states in the columns, including yielding, cover spalling, bar buckling, and structural collapse (i.e., dynamic instability) was predicted. Some simplified equations were derived for Montreal, Quebec, Canada, to estimate the mean annual probability of exceeding different damage states in the columns using the IDA results. The results indicated that the probabilities of exceeding different damage states were reasonably low. [ABSTRACT FROM AUTHOR]

A commissioning test of the deep-burial simulator at Queen's University, Canada, was conducted on a 3.05-m-diameter steel-reinforced polyethylene pipe to evaluate the behavior and design of this pipe class under deep burial. The diameter change measurements indicated that friction on the side walls was mitigated ensuring that the surface load was transferred to the pipe. Measurements of the displacement and rotation of the surface loading plates and strain in the steel reinforcing strips combined with visual observations after exhumation indicated that the pipe failed due to yielding of the steel reinforcing ribs. The surface pressure that the pipe was able to withstand exceeded the maximum burial depth specified by the manufacturer. Comparisons are also made between the experimental thrust forces at the springline and estimates from two design codes and a finite-element estimate; all were similar, with the rate of thrust increase with overburden pressure from the computer analysis approximately 8% larger than the measurement. Thus, the experimental results confirm that use of finite-element and code-equation analyses to design this pipe class for deep-burial conditions appear to be appropriate. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of revised seismic hazard values in the National Building Code of Canada (NBCC 2015) on the design of reinforced-concrete (RC) shear wall buildings. Five buildings with different heights located in three cities in Canada are selected. Toronto, Montreal, and Vancouver are selected to represent low, medium, and high seismic hazard zones. The buildings are designed according to the NBCC 2010 and then checked against the updated design spectral accelerations of the NBCC 2015. The seismic demands are compared, and the need for retrofit of existing walls is evaluated. The analyses showed that the maximum interstory drift ratios increased specially for buildings in Vancouver. The shear force and bending moment demands increased for most buildings in Vancouver by up to 32% and 60%, respectively. A significant decline in the moment overstrength ratio was noticed for walls in Vancouver, which indicates that flexural strengthening might be mandatory for these walls. Moreover, the code changes had a great negative impact on the walls' ductility for buildings in Vancouver due to the higher deformations exhibited. Several retrofit techniques available in the literature were discussed to enhance the flexural strength and ductility of RC shear walls as remedies for the consequences of the updated seismic hazard in Canada. [ABSTRACT FROM AUTHOR]

A lower shear strength and higher compressibility impose major challenges for construction on organic soils. Cementitious materials have been effectively used in the improvement of the engineering properties of mineral soils with low organic contents. However, limited studies have been devoted to the stabilization of the organic soils commonly encountered in forested regions in Canada. The present study investigated the effects of pulp mill fly ash (PFA) on the compressibility of a natural soil consisting of 26% organic matter. Fall-cone and oedometer tests were conducted on organic soil mixed with different PFA dosages (5%, 10%, 20%, 30%, 40%, and 50%), as well as on untreated soil samples. The mineralogical and microstructural aspects of PFA-treated organic soil were examined using scanning electron microscope and energy-dispersive X-ray spectroscopy techniques. The results suggest that when the organic soil was treated with PFA, its undrained shear strength and compressibility behavior were improved. Moreover, the potentially large settlement of organic soil can be reduced by the addition of PFA. The primary and secondary compression index (Cc and Cα, respectively) values decreased significantly when compared with the untreated organic soil, indicating that PFA stabilizers can effectively improve the creep behavior of organic soils. These findings indicate that the beneficial utilization of PFA for the stabilization of organic soils could be a practical step toward the environmentally sound management of this waste byproduct. [ABSTRACT FROM AUTHOR]

The lateral strength and stiffness requirements due to wind loads usually govern the design of tall buildings. The current building codes in the US, Canada, and Europe recognize the first significant yield point as an ultimate limit state. Consequently, the current design practices ignore the plastic capacity of structural systems in the nonlinear range, which could result in overdesigned buildings. Thus, the classical linear-elastic design arguments shall be reexamined with consideration of performance-based wind design (PBWD) approaches, innovative technologies, and materials. We are presenting two companion papers to demonstrate the benefits of considering the nonlinear capacity of structural systems in the design of wind-excited buildings. In this paper, Part I, we have postulated and then proved the capability of self-centering systems in controlling the possible damage accumulation in structural systems subjected to along-wind loads. Our arguments are based on an extensive parametric study through nonlinear time history analyses considering peak and residual ductility-demands, normalized hysteretic energy dissipation, and the rate of damage accumulation as performance indicators. Overall, the results of the parametric study revealed that self-centering systems could benefit the most from the ductility-based design due to their inherent recentering capability, higher energy dissipation, and lower sensitivity to wind duration. Consistent with the notion of PBWD, for self-centering systems, the companion Part II paper demonstrates the benefits of the ductility-based wind design in terms of economics and safety through structural reliability analysis. [ABSTRACT FROM AUTHOR]

Conventional design and evaluation procedures usually classify steel through-truss bridges as single-load-path structures; however, their historic performance has demonstrated considerable structural resiliency. This paper presents a study of the Grand River Bridge, a Pratt through-truss bridge in Cayuga, Ontario, Canada, that systematically investigates the load paths not conventionally assumed in design and evaluation. The bridge with individual truss members removed was analyzed using nonlinear finite-element analyses to investigate the alternative load paths and associated critical members and responses. A system reliability analysis was conducted to evaluate the failure probabilities of the bridge accounting for the member resistance uncertainties. The bridge was found to be sufficient to carry its nominal dead load, even for the worst case of removal of an end post. The end bottom chord and hanger vertical were found to be the critical tension chord and web member, respectively. If multiple alternative load paths exist, the variability of the system collapse load is much less than that of the critical member resistance. [ABSTRACT FROM AUTHOR]

This paper describes an experimental investigation of steel-sheathed cold-formed steel-framed shear walls by means of dynamic shake table tests. The objective was to evaluate the seismic performance and to identify whether the shear-wall behavior was consistent with past static tests, to obtain measures of damping and natural period of vibration, to investigate the influence of a second story, and to validate and improve the accuracy of the numerically predicted force-deformation response. The scope of study comprised five single-story and five double-story walls of the platform framing technique. Each wall was subjected to a suite of excitations: impact test to measure the linear-viscous damping ratio, harmonic excitation to estimate the natural period of vibration, and ground motions representative of the seismic hazard in Canada. An overview is presented of the test setup and dynamic loading protocols, as well as the test results and numerical model. [ABSTRACT FROM AUTHOR]

Research into the use of fiber-reinforced polymers (FRPs) in structures at the Royal Military College of Canada (RMC) during the past two decades has largely focused on two important military engineering goals-mobility and survivability. FRP research in the area of mobility has included the strengthening and repair of reinforced concrete beams and slabs and the development of portable lightweight bridges suitable for most wheeled and tracked vehicles. With respect to survivability, a particular interest is in the use of FRPs to enhance the blast resistance of structural columns and beams. Such research may be equally pertinent to improving the blast resistance of a broad range of critical domestic infrastructure worldwide, given both the increasing concerns about terrorist acts and the desire as well to improve resistance to accidental explosion. This paper will report on the experimental work of two of the most recent FRP research projects carried out at the RMC in support of military objectives-the development of a lightweight portable glass FRP bridge and the use of FRP to strengthen reinforced concrete structural columns against blast. A full-sized FRP box beam was constructed and tested in the laboratory and 28 half-scale reinforced concrete columns, some strengthened with either steel reinforced polymer (SRP) or with FRP, were tested in the field under blast load. From this research, it can be seen that FRP as a structural material offers significant advantages to military forces working in conflict zones, whether for traditional strengthening of damaged or understrength structures, lightweight portable bridge options, or as a means of strengthening structures against blast effects. [ABSTRACT FROM AUTHOR]

In the era of modernization, solid round steel bars are widely used in communication towers, which play a vital role in today’s world. Solid steel round bars are used as leg members, diagonal members, and horizontal members of a communication tower. Canadian Standard for Antenna towers and Antenna Supporting Structures, CAN/CSA-S37-01, specifies empirical expressions for the compressive strength of solid rounds based on the well-known Structural Stability Research Council column strength curves for nonsolid-round members as well as on the results from an experimental investigation on the compressive resistance of solid rounds carried out back to 1965. This paper provides a summary of the available literature on the compressive strength of solid rounds. Also, the results of the recently tested six large solid round bars at Ryerson University, Toronto, are presented. Correlation between the results from these tests and the current practice for the design of solid rounds is investigated. It is expected that the results from this paper direct the attention of code writers to more economical and safe empirical expressions for the ultimate compressive resistance of solid rounds. This would assist the practicing engineers in the evaluation of the load-carrying capacity of existing antenna towers since even a small increase in strength for live load can make the difference between demolishing a tower or leaving it in service. [ABSTRACT FROM AUTHOR]