Proceedings of the Canadian Society for Civil Engineering Annual Conference 2023, Volume 12

Monitoring specimen deformation is an essential aspect of structural testing. Strains and displacements are typically measured via electronic sensors (e.g., LVDTs and strain gauges). However, all of these sensors measure discrete spatial values. Moreover, placing instruments in contact with specimens poses a high risk of instrument damage in the event of sudden or explosive failures. Digital Image Correlation (DIC), which determines specimen displacements from a set of consecutive specimen images, overcomes both these shortcomings. Accurate DIC displacements depend on surface preparation and camera recording parameters, which require careful consideration in the context of a structural test. However, if these parameters are appropriately considered, for large-scale specimen testing it may be possible to obtain high-quality data with minimal risk and relatively low cost. In this study, the cost-effective use of DIC in the context of the testing of large-scale masonry walls (2 m in height) was examined. Readily available commercial recording cameras (iPhone 13, Go Pro Hero 11) were used to record videos of a prepared specimen in an experimental test and compared against readings from calibrated LVDTs. The results of DIC showed good agreement with LVDT readings. DIC was also found to permit the capture of “secondary” sets of data not typically measured in a routine experiment. These data pertain to explosive failure modes and experimental boundary conditions. The capture of secondary data can inform the interpretation of experimental results.

Masonry structures behave in a heterogeneous manner since they consist of different materials (i.e., blocks, mortar, grout, and reinforcement) with different mechanical properties. This makes their behavior more arbitrary, complicated, and challenging to predict due to the presence of various components. Although there is a considerable number of experimental investigations for masonry prisms in the literature, these investigations mainly focused on the ultimate capacity and corresponding strain, whereas complete data, including the post-peak behavior, is minimal. The interpretation of the complete compressive stress–strain curve of fully grouted and ungrouted web and boundary element assemblages is essential to understand the response of reinforced masonry shear walls (RMSWs) as structural elements subjected to lateral forces. Therefore, this study presents an experimental investigation of the mechanical properties of masonry assemblages under axial compression loading. Twenty-eight masonry prisms were constructed and tested to investigate the axial compressive response of fully grouted, ungrouted, and boundary element masonry assemblages according to CSA S304-14. Additionally, 100 × 200 mm cylinders of grout and 50 mm mortar cube specimens, sampled during the construction of the prisms, were tested according to CSA A179-14 and ASTM C109M-13, respectively. The results provide complete compressive stress–strain curves for grouted, ungrouted, and C-shaped boundary element prisms. The results showed that the ungrouted prisms have higher peak compressive stress than their grouted counterparts. Moreover, the boundary element prisms demonstrated relatively higher compressive strength than fully grouted web prisms.

Civil structures may experience various levels of damage during their life cycle due to exposure to different load conditions. Damage severity prediction in structural elements is a critical task to provide optimal maintenance in a timely manner that leads to reduced maintenance costs and avoids any catastrophic failure that may cause serious loss and danger to the owners and end-users. The acoustic Emission (AE) technique is one of the powerful non-destructive testing (NDT) methodologies that can be employed to detect and predict the severity of damage in different systems. Multivariate empirical mode decomposition (MEMD) is the extended version of EMD that can analyze multichannel signals collected from different sensors. In this paper, the damage severity prediction approach based on the combination of MEMD and the Gaussian mixture model (GMM) model is proposed. Unlike existing methods that rely on a single AE measurement, MEMD is used to extract the key AE components that belong to cracks using AE data collected from multiple sensors. The statistical features (e.g., mean, root mean square, kurtosis, skewness, and crest factor) of AE components obtained from MEMD are subsequently estimated. The selected features are then used in the GMM model to predict different severity damages (e.g., minor, and severe levels of damage). Numerical and experimental studies are conducted to validate the performance of the proposed method using a sine example and a large-scale reinforced concrete (RC) beam, respectively. The results show that the proposed approach can accurately predict the severity of damage in the structural elements.

This paper presents the results of two recent experimental programs (comprising a total of twenty-three large-scale tests) on weld-critical circular hollow section (CHS) connections. The first program involved testing fillet and partial joint penetration (PJP) groove welds in eleven moment-loaded CHS-to-CHS T-connections. The second involved testing PJP welds in axially-loaded transverse plate-to-CHS X-connections. The ultimate strength of the welds (at rupture) and non-uniform strain distributions adjacent to the welds at various load levels were measured, and reliability analyses of new weld effective geometric property provisions in CSA W59(:24) for the design of fillet- and PJP-welded CHS connections were conducted. The results of this study: (1) support the design of welds in CHS connections as “fit-for-purpose” in accordance with CSA W59, and (2) give further credence to the use of the (1.00 + 0.50sin1.5θ) directional strength-increase factor for the design of fillet welds in CHS members.

For reinforced concrete structures, most of the commercially available fiber-reinforced polymers (FRP) bars are pultruded using thermosetting resins. One of the practical limitations of the thermosetting-based FRP bars, however, is bending at the construction site. Similar to conventionally steel reinforcement bars, thermoplastic-based FRP bars have an advantage over thermosetting-based FRP bars in that they can be reshaped and bended after the initial production of straight bars. Recently, bendable thermoplastic-based FRP bars have attracted attention as they can simplify the manufacturing and construction process. Essentially, compared to thermosets, thermoplastics are tougher, more deformable, and have greater impact resistance. This study presents the results of an investigation on the mechanical tensile properties of newly developed glass-FRP (GFRP) bars pultruding using thermoplastic resin. The test results illustrate that the newly developed thermoplastic GFRP bars comply with the minimum requirements for the tensile strength of the GFRP bars. In addition, the results of this study reveal that the newly developed thermoplastic GFRP bars could be placed in the same category as high-grade GFRP bars in the different design provisions.

Evaluating bridge seismic resilience is one of the vital components of transportation system resilience. Efficient and reliable seismic protection systems must be implemented to decrease economic losses and casualties during a seismic event. Among different seismic protection systems for bridges, one of the most effective systems is the seismic isolation bearings. This study explores the seismic resilience sensitivity of a base-isolated bridge equipped with shape memory alloy (SMA)-based smart isolation systems. Considering a reinforced concrete bridge isolated with SMA bearing and conventional lead rubber bearing, this study examines the impact of these isolation systems on the seismic resilience of bridges. The seismic vulnerability of the base-isolated bridges is evaluated through detailed finite element analysis under pairs of 22 far-field ground motions representing seismic hazards at the bridge site. The comparative resilience of the base-isolated bridge systems is evaluated by considering appropriate loss and recovery models. The resilience assessment of SMA-isolation systems represents the adequacy and effectiveness of the base-isolation technique. The findings of the present study evince that the seismic performance, resilience, and recovery trajectory of isolated bridges are contingent upon the type of isolation system employed. Furthermore, the study revealed that the employment of shape memory alloy isolation bearing confers a robust seismic performance and resilience upon bridges, by virtue of their high capacity for dissipating seismic energy.

High-Intensity Wind (HIW) events, known as downbursts and tornadoes, have been identified as a major threat to transmission lines due to the frequently reported failures worldwide during those events. HIW events usually occur during thunderstorms, which are believed to have become more frequent recently due to global warming. Therefore, new load cases, representing the critical effect of downbursts and tornadoes on TL structures were incorporated into the ASCE-74 (2020) guideline, based on a 15-year research project conducted at the University of Western Ontario. One of the downburst critical load cases is when the downburst occurs at an oblique angle with respect to the transmission tower. The uneven transverse load distribution in this case produces a net longitudinal force transferred to the tower. The ASCE-74 (2020) guideline presents a set of charts that are used with a 3-D interpolation method to calculate this longitudinal force based on the conductor’s properties and the applied load. This paper aims to present a simplified method to calculate the net longitudinal force transferred to the tower due to the downburst oblique load case. The new approach is beneficial for practitioners in reducing the calculation’s time and effort.

Masonry cavity walls are often used as exterior walls in low-rise structures such as warehouses, schools, residential, and retail buildings. Cavity walls are advantageous as they include architectural, structural, and insulation properties in a single system. These walls typically consist of a concrete masonry unit backing, insulation, an air gap, and a brick veneer. Ties connect masonry layers together and transfer out-of-plane loading (such as wind) from the veneer to the backing. There are many ties on the market though many are proprietary. Generic ties are discussed in Canadian masonry standards (CSA S304-14 and CSA A370) with most research on these ties completed decades ago. However, the Canadian National Energy Code for Buildings has been updated with stricter thermal requirements for walls that require thicker insulation as well as thermal bridging to be considered. As part of a larger investigation into the thermal and structural effects of these changes in masonry cavity walls, 31 masonry wallets with cavity widths and materials representative of modern walls were constructed and tested in tension to assess their capacity and failure mechanisms. Two brick types were tested: clay and concrete. Tested ties include z-tie and rectangular ties common in older structures, plate connectors common in contemporary walls, and a novel inclined connector intended to improve wall composite action under longitudinal shear. Results show that, despite the larger cavity widths expected in future walls, all connectors satisfied the minimum requirements of CSA A370. Capacities were lower for z-ties (2.2 kN) and rectangular ties (1.9 kN) than for the plate connectors (4.3 kN) or the novel connectors (6.0 kN) with capacity dependent on the anchorage of the connector into the veneer. Connectors with anchorage ties had more warning of failure as those ties typically yielded before pullout but failures in all systems were controlled by mortar breakout in the brick layer.

The use of fiber reinforced polymer (FRP) composite structures is increasing these days due to their advantages, such as high strength, excellent durability, light weight, and fast construction. One group of FRP structural elements, which are manufactured in factories and are used in many structural and piping applications, is filament wound glass FRP (GFRP) tubes. Concrete filled fiber reinforced polymer tubes (CFFTs) have gained significant attention as a composite structure because the FRP tube provides confinement to the concrete core. Several studies have been conducted to understand the behavior of CFFTs. The results have shown that cross-ply and near-cross-ply FRP tubes have linear behavior. However, angle-ply FRP tubes have non-linear behavior, especially when they are filled with concrete. One of the most common angle-ply FRP tubes used in composite structures is ± 55˚ GFRP tubes, which has shown significant non-linear behavior when filled with concrete. In this study, previous research about testing ± 55˚ GFRP tubes under pure tension load is evaluated and a new configuration of CFFT has been tested under pure tension load to understand the exact behavior of ± 55˚ GFRP tubes when filled with concrete. According to the results, the ultimate strength and ultimate strain of the tube demonstrated an increase of 2.48 and 3.32 times compared to the hollow tube, respectively.

Tall loadbearing masonry walls are part of the main structural system used in warehouses and industrial facilities. These buildings feature exterior walls ranging from 4 to 9 m in height. Construction of such walls requires special considerations, such as using scaffolds and extra mason efforts to lay blocks around bar splices. Current construction methods create uncomfortable environments for masons, increasing the risk of injuries and time construction while reducing productivity. This paper introduces a new construction method that enhances the constructability of tall masonry walls and reduces the difficulties associated with traditional construction methods. Five reinforced masonry modular panels -eight courses high- were built using 20 cm concrete masonry units to form a full-scale 9 m tall masonry wall. These panels were assembled on top of each other while ensuring mild rebar continuity using mechanical couplers. Post-tensioning threaded bars were also used to ensure wall integrity and enhance wall performance under out-of-plane loads. The experimental results showed good performance of the new wall system while the effect of post-tensioning force and the base condition on the wall performance is discussed.

With the advancement of mass-timber construction technologies, the requirement for Performance-Based Fire Design (PBFD) becomes paramount. PBFD is known to save costs, but in practise, design changes leading to re-design can cost more than any savings that might be had. To combat this, interdisciplinary understanding and coordination must be improved. The authors found that there were little to no holistic guides for architects on the fire dynamics of timber compartments, only guides on how to use prescriptive codes. Rather than overbearing the reader with complex physics, the aim of the paper is to provide architects and other professionals with a holistic reference on the relationship between architectural features and the fire dynamics of timber compartments. This is done by demonstrating through the holistic review of 33 full-scale timber compartment tests, an analysis of the relationship between common architectural changes (opening sizes, finishes, and occupational use among others) and their impacts on fire performance (time to flashover, intense burning durations, maximum temperatures reached, etc.). Both a qualitative review of observations made during the tests and plots comparing architectural metrics against fire dynamic metrics are made, as well as their corresponding correlation coefficients. It was found that floor area and ceiling height have a significant relationship with maximum temperatures and Heat Release Rate (HRR). It was found that exposed timber compartments had faster times to ignition and longer intense burning periods. Correlation values indicate that exposed timber ceilings have a greater relationship with fire dynamics than exposed timber walls. This paper reveals to the reader the significance of architectural changes on fire dynamics and the complex understudied nature of timber compartment fires. Architects and owners building a modern mass-timber structure will become acutely aware of how design changes will likely instigate further costly project research to inform re-design. In future research, the authors will translate this research to prospective disciplines via. BIM.

A single stage multi-scale feature fusion convolution network integrated with vision based metrological characterization of cracks in concrete pavements is established to deliver an end-to-end crack detection and measurement (CDM) system. The convolution network considers the learning adaptability of the neurons and forces the neural model to evade correlation dependencies in learning features, resulting in a well-represented model. The well-learnt model exhibits high performance on crack induced structures. Post crack detection vision-based processing on the region encapsulating the crack is performed enabling extraction of crack edges by extending the Canny algorithm. Low mean error in estimated crack width validates the results. Finally, the integration of crack detection with its measurement provides a fully functional and implementable CDM solution.

Climate change and its worldwide effect on temperature is a well-documented phenomenon. As with much of Canada's transportation infrastructure, reinforced concrete bridge girders experience the effects of these changes. Inconsistent heating of bridge girder cross-sections results in large nonlinear temperature gradients. However, bridge design codes and specifications rely on historical climate data to inform design requirements. Furthermore, the location should be considered when determining temperature distributions due to the wide variations in climatic conditions in Canada. However, the Canadian Highway Bridge Design Code (CHBDC) specifications provide a fixed thermal gradient profile without considering the variation in the Canadian climatic regions. In this study, the temperature distributions, variations, and gradients were investigated for a concrete box girder for different Canadian climate regions. Two separate one-month transient thermal finite element models were developed for each representative city of the climate regions to develop the concrete girder's temperature behaviors and distributions. The results showed that the daily maximum mean temperatures and the extreme daily positive thermal gradients do not coincide. The predicted maximum mean temperatures were higher than the CHBDC maximum mean temperatures of the concrete box girder for the selected cities. Comparisons between the proposed thermal gradient profiles, values, and patterns with the CHBDC thermal gradient specifications were conducted. The comparisons showed that one fixed thermal gradient profile is inadequate to cover the variation in the thermal gradients and differentials of the Canadian climate regions.

Incorporating GFRP stirrups as shear reinforcement in precast concrete tunnel lining (PCTL) segments is a practical approach to enhance the punching performance of infrastructure projects. Punching loads in tunnels can be induced by the expansion of rock or other geotechnical conditions on their extrados surfaces. This study reports the first-ever experimental investigation on the punching-shear behavior of precast concrete tunnel segments with glass-fiber-reinforced polymer (GFRP) bars as flexural reinforcement and GFRP stirrups as shear reinforcement. Two full-scale PCTL specimens reinforced with the same longitudinal and transverse ratios were fabricated and tested under point loads until failure. A rhomboidal-shaped segment measuring 2100 mm in length and 1500 mm in width with a thickness of 250 mm was used in the experimental program. One of both segments had shear reinforcement using a new arrangement technique to assess its contribution to punching capacity. The results are reported and discussed in terms of general behavior, cracking pattern, reinforcement strains, and mode of failure. The experimental results revealed that both segments exhibited final punching-shear failure with no signs of concrete crushing and a similar crack pattern. However, the segment with shear reinforcement had a higher cracking load, stiffness, and punching capacity. These results indicate that using stirrups in GFRP-reinforced PCTL segments represents a realistic solution for the structural integrity of tunnels where initial cracking and ultimate capacity are the governing criteria.

Soil-steel structures play an important role in the infrastructure of mining industry. The ease to ship and construct in remote locations distinguishes this system comparing to conventional concrete and steel structures. In addition, the ability to dismantle the structural system and restore the site to the initial condition with the least environmental cost at the end of mining projects is considered a great asset to the environment. Soil-steel structures are widely used in supporting heavy haul roads subjected to excessive loadings. This study presents a three-dimensional numerical investigation for soil-steel structures subjected to various heavy weight haul trucks. The numerical technique is validated by the field measurements of a fully monitored 10.0 m span soil-steel structure subjected to tandem axle loading until failure. The numerical simulation succeeded to capture the ultimate capacity of the steel structures under truck loading conditions. The validated numerical technique is then used to investigate the ultimate behavior of the world’s largest-span soil-steel structure with a span exceeding 32 m. The results demonstrated the ability of soil-steel structures in sustaining various haul trucks with gross weight of more than 850 tons.

Over the last few years, researchers have studied fiber-reinforced polymer (FRP) -reinforced concrete members’ flexural and shear behavior. However, there is a need to study additionally the compressive behavior of concrete columns reinforced with FRP bars. Although some studies are done on reinforced concrete columns with FRP bars, it is not recommended to use FRP bars as compressive reinforcements in columns. The main reason is the negligible contribution of FRP bars during the failure of compressive elements with a low strain value. In this case, by adding fibers, the ultimate strain of concrete will be increased in compression and improve the FRP bars’ contribution to load bearing. Therefore, in this study, three full-scale fibrous self-consolidating (SCC) circular columns with dimensions 305 mm in diameter and 1500 mm in height were tested under axial compression load. The columns were reinforced using longitudinal and spiral stirrups glass FRP (GFRP) and basalt FRP (BFRP) bars. The test variables included reinforcement type (GFRP and BFRP), and the effect of using synthetic fibers. Using fibrous SCC in columns reinforced with GFRP and BFRP bars improved the load–deflection behavior of columns.

This study aims at providing such pivotal knowledge necessary to better understand the behaviour of aluminium members through experimental investigations. With this objective, a comprehensive experimental study was performed to analyze the buckling behaviour of extruded aluminium members under compression with different section shapes, such as rectangular, square, I-shapes, and complex shapes. Overall, 14 stub column tests were performed and 24 cross-sectional tests under axial and eccentric compression are currently being conducted to investigate the local buckling behaviour of aluminium sections. In addition, 14 tensile coupon tests were carried out to further characterize the material response, and with also the intention of further using this data in accurate FE models. Also, initial geometrical imperfections in each specimen were measured mechanically as well as using 3D scanners. In order to investigate the buckling behaviour of aluminium members beyond experiments, the development of advanced non-linear shell numerical models is under way; the latter shall be validated through the measurements and results of the experimental study. Eventually, the results of the experimental and numerical studies shall enable developing a novel design approach for the prediction of the resistance of aluminium members, by means of the “Overall Interaction Concept”.

Given the difficulties of achieving sufficient load transfer using intermediate modulus carbon fiber-reinforced concrete polymer (IM-CFRP) laminates, limited research has been carried out on strengthening steel structures with CFRP composites. The recent development of a new generation of ultra-high modulus-CFRP (UHM-CFRP) composites has made it possible to broaden the spectrum of potential strengthening applications, particularly those involving structural steel elements. This study investigates the effect of the bond length on the behavior of the adhesively bonded UHM-CFRP to the steel members. In this paper, a total of six adhesively bonded UHM-CFRP/Steel double lab shear (DLS) joint specimens—including three DLS joint specimens with a bond length of 90 mm and three DLS joint specimens with a bond length of 180 mm—were prepared and tested. The experimental results of this study are presented in terms of failure mode, ultimate load carrying capacity, and ultimate longitudinal displacement. The experimental results illustrate that the bond length of 180 mm is the effective bond length for the UHM-CFRP composite strengthening system to the steel members. In addition, the experimental results show that the UHM-CFRP composite system used in this work demonstrates superior performance with a high bond strength and elongation for the UHM-CFRP composite strengthening system to the steel members. The experimental outcomes and conclusions of this work can be implemented in assessing and exploring the feasibility of using UHM-CFRP composites for the strengthening and rehabilitation of steel structures.

With the bloom of construction, there is an increasing need to span larger and larger spans that can be used in workshops, factories, and alike. The traditional go-to solution for large spans is steel due to its strength and fast construction. However, the cost of steel is increasing in addition to the fact that it is a non-ecofriendly material, as its manufacturing incurs tremendous energy consumption. An alternative solution that has not been utilized in Egypt and similar arid countries is wood due to the import of most of the wood in Egypt. The main goal of this study is to develop a large-span curved beam fabricated from laminates of locally grown Casuarina glauca wood that will be a more economical and sustainable alternative to steel structures. Flexural strength tests were performed on scaled beam models to determine the mechanical properties of Casuarina glulam in bending. Test results were used to develop structural analysis models to assess the structural soundness of a main span beam made from such material. The cost-effectiveness and the eco-friendliness of this design alternative are compared to those of steel and concrete.

Reinforced masonry shear walls (RMSWs) are responsible for resisting lateral loads from seismic and wind events as well as carrying gravity loads. Adding masonry boundary elements at the end zones of RMSWs has proven to provide the required ductility and stability of reinforced masonry shear walls with boundary elements (RMSW + BEs). The prediction and quantification of the wall's seismic performance during earthquakes is crucial. This study focuses on a numerical investigation of four fully grouted RMSW + BEs subjected to dynamic loadings. Previously tested RMSW + BEs under quasi-static cyclic loading are adopted in this study. The walls have aspect ratios of 1.5 to 3.2, vertical reinforcement ratios of 0.56 and 0.68%, and horizontal reinforcement ratios of 0.3 and 0.6%. A 2D numerical model was developed using the Extreme Loading for Structures (ELS) software to simulate the nonlinear seismic behavior of the RMSW + BEs. The numerical model was validated against the experimental results of the studied walls. Subsequently, the walls were subjected to incremental dynamic loading using a set of selected and scaled Eastern Canada simulated earthquake records from the Atkinson database. The seismic performance characteristics of the walls, such as the initial stiffness, stiffness degradation, idealized yield displacement, and ductility- and overstrength-related force modification factors, were quantified for both static and dynamic loadings of the walls. The results showed a variation between the results of both loading scenarios for the initial, effective, and ultimate stiffnesses, ductility- and overstrength-related force modification factors. Moreover, the wall lateral stiffness, strength, and energy dissipation were higher due to the dynamic loading than the quasi-static cyclic loading. This study highlights the variation of the dynamic response of RMSW + BEs compared to their counterparts when tested under quasi-static cyclic loading.

Canada is suffering from a persistent housing shortage, especially in Indigenous communities, which was reported by the United Nations Assembly General on Adequate Housing in 2019. Modular housing is considered an adequate solution to reduce the shortage of housing needs. Prefabricated modular structures are becoming popular in the construction industry, particularly during times of high demand (e.g., after a natural hazard), through which components of the building are prefabricated off-site in a controlled setting and then transported and assembled on-site. Although volumetric modular structures have been widely used, this module is not ideal for transporting to remote areas (e.g., Indigenous communities). The transportation of these units and lifting processes can risk damaging both the structural and non-structural members. Alternatively, the current study proposed a novel modular connection configuration for connecting the modular panels (i.e., two-dimensional) using bolted connection on-site to build volumetric housing and avoid transportation limitations without elevating costs. This current study aimed to numerically investigate the mechanical and deformation behavior of the proposed beam-to-column connection for steel modular structures under monotonic loads. Two geometric parameters: the extended plate’s thickness and bolt arrangement (square and rectangle) were examined using non-linear finite-element modeling to investigate their effect on the connection moment capacity and its inelastic rotation. All specimens showed local buckling and bolt-bearing failures within the beam member.

Cable domes are lightweight flexible structures and highly sensitive to geometry change. Different forms of cable domes have been developed over the past decades. As one of the newly developed forms, double-curvature cable domes have been proven to have more stability than the corresponding positive ones and better rigidity than similar double-curvature cable nets. One critical factor to be considered when designing double-curvature cable domes is the effect of changing geometry on the optimized weight and displacement of such structures. Several geometrical parameters may affect the size and prestress optimization of these forms, in terms of structural weight and stiffness, such as number of hoops and sectors, height/diameter, rise/sag, and inner hoop diameter. This paper investigates the effect of such parameters on the optimized weight and prestress level of this new form at several maximum displacements. The optimization technique adopted in the current study depends on prestressing the dome with an initial value of prestress level that ensures starting from a feasible state, i.e., with no slack in cables. Then, the prestress level is increased incrementally until reaching a maximum displacement of less than span/1000. At each increment, the dome is optimized to the minimum weight. The optimized values at each increment are fitted to power curves that relate both the optimized weight and prestress level to the maximum displacement. These fitted design curves are developed for a dataset of the geometrical parameters stated above and compared based on two criteria; the first is the optimized weight at maximum displacement equal to span/250 as recommended by design codes, while the second is the effect of increasing the dome stiffness on the optimized weight when decreasing the maximum displacement from span/250 to span/1000.

With the availability of numerical modelling techniques, engineers and researchers can simulate and assess structures without the costly and laborious constraints of experimental studies. The finite element method (FEM) is a well-known and widely used modelling technique to simulate structures. In contrast, the applied element method (AEM) is a more recent technique, but is very promising in simulating extreme loading events on structures, such as earthquakes. The objective of this study is to compare both modelling approaches and the validation results of each technique by modelling two fully grouted reinforced masonry shear walls (RMSWs). SeismoStruct and Extreme Loading for Structures (ELS) are the selected software to apply the FEM and AEM, respectively. The results of each model were plotted against experimental results from the literature. Each modelling technique was able to capture the lateral cyclic performance of the fully grouted RMSWs. However, the SeismoStruct model required a significantly lower runtime compared to that of the ELS models. It was found that for fully grouted RMSWs, the FEM in SeismoStruct is the preferable modelling technique. However, this conclusion does not apply to other types of masonry walls such as partially grouted RMSWs, where SeismoStruct falls short in providing modelling tools to simulate them. Contrarily, ELS provides more flexibility for modelling in terms of element and material models. Furthermore, due to the idea of continuum mechanics in the FEM, the AEM is preferable when simulating a collapse. Modelling the separation of elements is more challenging in the FEM, whereas, in the AEM, elements are easily separated and can collide with the ground.

Aluminum possesses numerous advantages as a construction material such as a high strength-to-weight ratio, excellent durability, corrosion resistance, recyclability, and formability. Nevertheless, due to the limited knowledge of their buckling behavior and efficient design recommendations, aluminum alloys are yet to be accepted widely in structural applications. To enable a more efficient design for aluminum structural members, this study aims at analyzing the buckling behavior of aluminum extrusions through experimental studies. With the specific objective to investigate the local buckling instability of aluminum extrusions, four series of stub column tests with axial compression and ten short beam-column tests with eccentric compression were performed on Circular Hollow Sections (CHS) with 6061-T6 aluminum alloy. The initial geometrical imperfections of the specimens were measured by using professional 3D scanners and the material properties were obtained through tensile coupon tests.

The safety of dams is of extreme importance, considering the high economic value and cost of failure. To assess the performance of these structures over their lifetime, vibration monitoring can be a useful tool. However, in hydroelectric generating power plants, rotating machinery can introduce harmonics into the measurements and make current methods of modal parameter estimation invalid, necessitating harmonic removal. While recent research has focused on harmonic removal in rotating mechanical machinery like wind turbines and large generators, there is a gap in understanding of monitoring gravity dams in environments with significant harmonic contamination. Most ambient vibration tests of dams have been conducted on arch and buttress-type structures, which have experienced relatively low harmonic contamination. To address this gap, a study was performed on the Mactaquac Generating Station, the largest hydroelectric power plant in the Maritime provinces, using full-scale monitoring data as part of the Mactaquac Life Achievement Project (MLAP). The study found that under low operation demand, it was possible to successfully estimate the benchmark modal parameters of the structure. However, during high operational demand, the measured signals were dominated by harmonic content, which caused several errors in the modal estimation results compared to periods of low demand. However, by reducing the harmonics in the signal, the first four mode shapes of the dam structure were successfully identified. This demonstrates that harmonics can significantly impact the accuracy of mode estimation, but their effects can be mitigated through harmonic reduction techniques.

Foundations on expansive soil have been a long-known challenge in the construction industry. The established methods for designing shallow foundations on expansive soil are either ground improvement techniques like the removal and replacement of existing soil, preloading, or superstructure compensation like designing a heavier foundation, allowing free movement at structural connections, raising the foundation to eliminate contact with native soil. While all the stated techniques work, they can be expensive and come with their own set of limitations. A new design approach with ground improvement using polymeric geocell and granular infill under the foundation has been discussed in this paper. Reinforcing soil is an established technique to improve soil modulus against the action of vertically downward forces. Particularly with high strength geocell research and applications have shown that there are multi-fold improvements in the bearing capacity of native soil, bridging softer areas and reducing the risk of strain softening. A method has been established to numerically model the effect of soil reinforcement while carrying out shallow soil foundation designs subject to upthrust. The study does show foundation soil stiffened with high-strength geocell. Thus, having thinner slabs and less reinforcement can be an economic and more sustainable solution than conventional systems. There is an observed minimum of 59% reduction of effective upward displacement. The importance of optimizing the design to maximize the effect of reinforcement is evident in this study.

A concrete deck slab from a major Canadian bridge has undergone an extensive condition assessment using non-destructive testing (NDT). The bridge suffered from extensive use of de-icing salts during the winter seasons, combined with frequent freeze–thaw cycles, and hot and humid summers. Although numerous and extensive maintenance and rehabilitative measures were completed on various components of the bridge, the severe deterioration continuously reduced the structure’s service life. This paper presents the results of the corrosion potential and state of the temperature reinforcement embedded in a post-tensioned concrete deck slab that had suffered deterioration from chloride-induced corrosion. NDT techniques including half-cell potential mapping and the connectionless electrical pulse response analysis were implemented on the embedded steel reinforcement. Concrete electrical resistivity measurements were also obtained from the concrete surrounding the steel components. Although no signs of corrosion-induced concrete cracking were identified at locations around both layers of steel reinforcement, both layers still exhibited high corrosion rates. However, corrosion was more severe for the top reinforcement possibly due to the penetration of high concentrations of chlorides from the bridge deck. In addition, concrete surrounding the bottom reinforcement was characterized by low surface resistivity values, indicating moderate to low chloride ion penetrability resistance, while concrete surrounding the top reinforcement had high surface resistivity values, indicating very low chloride ion penetrability properties.

Hollow structural sections (HSS) have high torsional rigidity, which makes them an ideal candidate for structural applications to combat lateral-torsional buckling. However, as the bending moment applied on HSS members increase, the risk of local buckling of the HSS members also increases. In recent studies, polygonal hollow sections (PHS) with discrete bends have been shown to be effective in reducing local buckling and improving rotational capacity under strong axis bending. However, the effectiveness of these bends under weak axis bending has not been studied. This paper investigates the structural performance of PHS as well as that of rectangular hollow sections (RHS) with comparative dimensions through a series of four-point bending tests about weak axis with the aid of distributed fiber optic strain sensors (DFOS). The smaller RHS305 beam reached its theoretical yield moment capacity, while the moment capacity of the larger RHS356 beam was 14% less than the theoretical yield moment capacity. The moment capacity of the smaller PHS305 beam is 10% less than its theoretical yield moment, while that of the larger PHS356 beam is 23% less. DFOS was found to be effective in identifying and quantifying stress concentration as well as in monitoring the progress of local buckling in thin-walled PHS and RHS beams.

The Seaway International Bridge in Cornwall, Ontario, consists of two distinct bridges, the South Channel Bridge (SCB) and the North Channel Bridge (NCB), that link the Akwesasne Mohawk Territory to the United States and Canada across the St. Lawrence River. Both the bridges are maintained by Seaway International Bridge Corporation (SIBC). The Federal Bridge Corporation (FBCL) and the Saint Lawrence Seaway Development Corporation (SLSDC) collaborate to manage the SIBC. The South Channel Bridge first opened in 1958 and is a suspension bridge with a total length of 1061 m and a roadway width of 8.2 m. The stiffening truss of the bridge deck is connected to the towers by eight rocker arms. The rocker arms have pin-ended connections and therefore are expected to primarily be subjected to axial loads. One of the rocker arms developed fatigue cracks and fractured in 2015 causing the deck to descend 150 mm at the expansion joint. The entire rocker arm assembly was replaced, and by 2021 concerns about the other seven rocker arms led to the installation of a monitoring system consisting of 32 vibrating wire strain gauges. This paper will review some key findings from the monitoring and the fatigue analysis used to assess the remaining life of the rocker arms.

Composite reinforced concrete elements such as bridge girders typically comprise precast girders and cast in-situ slabs. However, composite members are subjected to horizontal shear induced by gravity loads at the interface between the precast beam and the slab. Shear connectors crossing the interface are used to ensure the composite action and the integrity of these elements. To overcome the steel corrosion problems, glass fiber-reinforced polymer (GFRP) reinforcement has been implemented as the primary reinforcement in concrete elements (bridges and parking structures), especially in harsh environments. Accordingly, this study investigates the performance of GFRP as a shear friction reinforcement in composite concrete elements. The shear friction capacity of GFRP shear connectors at concrete cold joints (concrete-to-concrete interface) without a roughened interface was experimentally examined. The study included three specimens, each comprised of two L-shaped blocks cast at different times to achieve the desired shear plane condition. The specimen measured 1050 mm long, 600 mm wide, and 300 mm thick, resulting in a shear plane of 400 × 300 mm. One specimen was fully reinforced with steel, whereas the others were fully reinforced with GFRP bars. The shear connectors were size 15 M (15.9-mm diameter) Z-shaped steel or GFRP bars. The specimens were tested under monotonic axial load through a push-off test. The main test parameter was the reinforcement ratio of bar connectors crossing the shear plane. The test results were analyzed in terms of load-slip relationship, capacity, and mode of failure. Results have shown the applicability of using GFRP reinforcement to resist shear friction in a comparable manner to its steel counterpart.

Partially grouted reinforced masonry shear walls (PG-RMSWs) have emerged as an efficient and economic seismic force-resisting system (SFRS) in North America. Unlike fully grouted reinforced masonry shear walls (FG-RMSWs), where all masonry cells are grouted, in the PG-RMSWs system, grout is only placed in cells with vertical reinforcement and horizontally reinforced bond beams. Despite the economic benefits of PG-RMSWs systems in low-rise buildings, the use of such a system in mid- and high-rise structures is still questionable since minimal research has been conducted to study the behavior of flexural-dominated PG-RMSWs. The literature lacks comprehensive studies investigating different limitations adopted for flexural-dominated PG-RMSWs in the North American masonry design standards (i.e., TMS 402/602-16 and CSA S304-14). These limitations have a major influence on the ductility of the walls, the energy dissipation capacity, and the damping characteristics. Most of the conducted studies targeted FG-RMSWs and were then adopted for PG-RMSWs with some modifications and conservatism that do not always reflect the actual case. Accordingly, this study investigates the effect of various design parameters on the quasi-static lateral cyclic response of flexural-dominated PG-RMSWs. Eight walls with different aspect ratios were designed to represent the CSA S304-14 and TMS 402/602-16 different seismic provisions for moderately ductile reinforced masonry shear walls (RMSWs) and intermediate RMSWs, respectively. A 2D numerical simplified micro model was developed using the Extreme Loading for Structures (ELS) software to model the studied PG-RMSWs. The results showed that PG-RMSWs that satisfy seismic provisions of the TMS 402/602-16 intermediate RMSWs don’t possess enough ductility as required. On the other hand, the CSA S304-14 code provisions for moderately ductile reinforced masonry shear walls can be extended to cover partially grouted flexural-dominated RMSWs.

In Canada, about 45% of bridges reached their life expectancy and the overall budget for maintenance and rehabilitation only covers about 59% of the estimated required cost. It is likely that many of the bridges classified as “fair” will reach a poor condition before being upgraded. This represents an enormous financial burden that faces Canada in the near future. In addition, recent natural and man-made disasters in Canada and around the world have further highlighted the difficulty that affected communities faced to recover socially and economically from these unexpected shocks. Many researchers convey that floods can be considered one of the principal reasons for bridge failure in Canada and the rest of the world. Under these circumstances, this study aims to study economic losses due to floods in Manitoba. Historic records about flood economic consequences have been collected from the CatIQ platform. These costs per square kilometers have been quantified in Manitoba as well as in nearby areas prone to these events. The application of this approach can help decision-makers and code-writers to develop probabilistic risk-based models to quantify the risk of highway bridge failure due to floods for design and evaluation purposes.