Proceedings of the Canadian Society for Civil Engineering Annual Conference 2024, Volume 14

Table of Contents

1. Frontmatter

2. Natural Vibration Analysis for Axially Loaded Steel Members with Angle Cross-Sections

   Houtan Tahmasebi-Orimi, Arash Sahraei, Magdi Mohareb

   Abstract

   The susceptibility of axially loaded steel members with angle cross-sections to vibrations depends on their fundamental natural frequency. Design steel standards guard against excessive vibrations by enforcing slenderness limits of 200 for compression members and 300 for tension members. This approach indirectly controls the member’s natural vibration but does not reflect the effect of axial force level within the member, nor the type of connection at the member ends on its susceptibility to excessive vibrations. For members with angle cross-sections, in which the shear centre is offset from the section centroid, the fundamental vibration mode involves a combination of flexure and torsional deformations. The corresponding natural frequency depends on the cross-section geometry, member span, level of axial loading with the member, end connection details, and the eccentricity of the axial relative to gusset plates at both ends of the member. Within this context, the present study presents the results of a parametric study that investigates such effects by conducting a series of natural vibration analyses based on a stressed Eigen-value type of solution, for a spectrum of compressive and tensile members with angle cross-sections. The analyses are based on closed-form solutions and shell finite element models developed in Abaqus. The study presents a step towards proposing refined slenderness limits for axially loaded members.

3. A Novel Hybrid Machine Learning Model for Rapid Prediction of Urban Wind Flow

   Foad Mohajeri Nav, Reda Snaiki

   Abstract

   Understanding airflow within urban areas is crucial for ensuring pedestrian comfort, optimizing building ventilation, managing air quality, and evaluating how wind affects structures. Computational Fluid Dynamics (CFD) is a recognized method for simulating wind flow in cities. However, its computational demands related to high-fidelity schemes, such as large eddy simulations (LES), pose a significant challenge, particularly when dealing with probabilistic analysis, risk assessment, and real-time predictions. Moreover, despite the availability of faster CFD simulations like Reynolds-averaged Navier–Stokes (RANS), these low-fidelity (LF) predictions are often inaccurate for simulating wind flow in urban areas. To address these challenges, this study proposes a novel hybrid machine learning model comprising a dimensionality reduction technique and a long short-term memory (LSTM) network. Specifically, proper orthogonal decomposition (POD) is used for dimensionality reduction, and then the time-dependent POD coefficients are obtained via direct projection of the LF and HF signals onto the identified POD basis. An LSTM network is subsequently trained to map the LF POD coefficients to their corresponding HF POD coefficients. To demonstrate the performance of the proposed approach, a simplified case study involving wind flow in an urban area is presented. The analysis confirms that the introduced framework can rapidly and accurately predict HF urban flow.

4. User-Friendly Tool to Design Piled-Wharves for the Dynamic Effect of Wave Load

   Caleb Wood, Fadi Oudah

   Abstract

   Marine structures are subjected to harsh environmental conditions including wave load. It is common practice to use the Morison equation to obtain the wave force applied to a supporting pile. One of the main assumptions of the Morison equation is a rigid pile, meaning the dynamic response cannot be computed using the Morison equation on its own. The objective of this work is to provide a framework that allows the dynamic pile response to be extracted from the Morison equation through user-friendly design aids. The design aids consist of deformation response curves for a given set of wave characteristics for a specific pile diameter derived using computational fluid dynamics (CFD). Deformation response curves express the relationship between static and dynamic responses of a pile for a pre-defined range of equivalent lateral stiffnesses. Static response is obtained by applying the maximum Morison force as a static point load, while the dynamic response is computed through CFD. This work presents the deformation response curve for a circular HSS457 pile that is fixed at its base and pinned at its top. Preliminary findings indicate that the dynamic response is dependent on three parameters, the geometrical properties of the pile, wave characteristics, and the ratio between the water depth and pile length. A case study for utilizing the calibrated tool is demonstrated.

5. Use of Automated Geotechnical Instrumentation to Monitor Post-disaster Stability of a Highway Embankment Failure

   Campbell Bryden, Jared McGinn

   Abstract

   When highway embankment failures occur, the owner must assess site conditions to determine whether the highway may remain operational in the time leading up to permanent repairs. The topic of this study pertains to a significant embankment failure that occurred in June 2023 in Edmundston NB; this failure occurred at the Two-Mile Brook crossing, where the hydraulic asset consists of a 3.5 m by 2.9 m concrete arch culvert beneath 15.2 m of fill. After heavy rains in June 2023, restrictions on the culvert flow capacity led to rising headwaters causing a significant embankment failure. The failure destroyed municipal infrastructure and impacted a neighboring residential property. The highway was closed immediately for public safety, and design of a replacement structure was initiated immediately. To provide continued operation of the highway in the time leading up to permanent repairs, a 60 m-long single-lane temporary modular bridge was installed near-grade on timber abutments, and an automated monitoring system was installed for public safety. A 25 m-long ShapeArray was installed horizontally beneath the modular bridge and near the critical abutment to monitor vertical deformation; should deformations in excess of the threshold value be recorded, interested parties would be notified immediately by “push-notification” sent automatically using a cloud-based data-hosting service. During the 56-day monitoring period described herein, no alerts were triggered; the data suggests that the instrumented bridge abutment settled by approximately 20 mm and that the embankment settled by approximately 2–4 mm. The innovative risk-informed decision-making process pursued in this disaster response was shown to yield an acceptable outcome.

6. In-Plane Strength of a New Self-aligning Bolted Connection for Precast Concrete Wall Panels

   Kate Cunningham, Alan Lloyd, Samira Rizaee

   Abstract

   The modular construction industry has seen significant growth in recent years owing largely to its faster construction, improved quality, and lower costs. The need for a design that can help manage tolerance errors has been identified. To address this, a new self-aligning bolted connection for use between precast wall panels in total precast construction projects was developed. The connection is made of a u-shaped insert which is bolted to a frame embedded within the wall panel. A z-plate connects adjacent u-shaped horizontally while a flat bar connects the u-shapes at vertical connections. The z-plate and long flat bar are then bolted in place. In-plane, tensile, system testing was conducted on the horizontal connections. Four 2 m × 2 m × 200 mm reinforced concrete wall panels were built with the connections in place. The u-shaped inserts were attached to the internal frame of the wall panels using varying anchorage methods. A total of 16 connections were tested, six of which used no additional anchorage when connecting to the frame. This was compared to four connections using three anchor bolts, and another four connections using five anchor bolts. Two of the connections were in double configuration where two u-shaped inserts were connected to the frame at a location, compared to the single connections that only used one. One of these used ten anchor bolts and the other used six that connected into a steel plate. The single connection with no anchorage failed either at the internal frame or the z-plate depending on the configuration of the internal frame at the location. The singles with three and five anchor bolts exhibited similar behaviour and failed at the z-plates and the doubles were found to have nearly double the capacity of the singles. The failure of the z-plates was shear tear-out failure of one of the main structural bolt holes.

7. State-of-the-Art Review of Physical Modelling of Structural Systems

   A. El Naggar, M. A. Youssef, H. El Naggar

   Abstract

   Physical modelling is the process of creating reduced-scale models capable of predicting aspects of real-life structures or systems. These models comply with spatial and financial constraints and could be used to capture certain complex aspects of structural systems, which adds a different dimension to behaviour prediction. In fact, via physical modelling, the behaviour of a structure could be studied under various loading and environmental conditions in a controlled laboratory setting. Small-scale models enhance the feasibility of experimental tests while saving time and lab resources. In this study, a state-of-the-art review is conducted on the two most prominent physical modelling techniques, with a critical comparison of the strengths and limitations of each method.

8. Coastal Bridge Climate Vulnerability Mapping: Network-Level Flood Scour Risk Assessment in Nova Scotia

   Rishav Jaiswal, Mingsai Xu, Jing Li, Will Crocker, Hao Yang, Cancan Yang, Wael El-Dakhakhni

   Abstract

   Coastal areas worldwide are experiencing a profound impact from climate change, with transportation systems along the coastline being particularly vulnerable. Failure of bridges may severely disrupt the serviceability of transportation networks, causing considerable economic and social losses. The extensive destruction caused by the Nova Scotia Flood in 2023 is a stark reminder of the impact of climate change on the Atlantic coastal regions of Canada, where extreme weather events, particularly flooding, continue to occur with increasing frequency and intensity. The increased flooding leads to higher riverbed erosion and scours around bridge foundations, exacerbating the risk of bridge collapse. To address these challenges, this study presents a risk-based assessment framework that integrates component-level analyses, including the estimation of scour depth based on climate conditions and bridge age, with network-level considerations like potential detour lengths necessitated by bridge failures. Particular focus of this study is the development of a deep learning model that seeks to understand the dynamics between climate variables (temperature and precipitation) and streamflow patterns. This model is then applied to forecast future streamflow and to assess the potential risk of bridge damage from water erosion at abutments under different climate scenarios. When this approach is applied to the examination of bridges in Nova Scotia, it reveals a heightened risk of failure due to flood-induced scour, emphasizing the necessity for strategic adaptation planning and the prioritization of bridge maintenance to enhance resilience against future climate threats. These findings offer a preliminary and exploratory analysis focused on quantifying the negative effects of climate change on bridges, from individual infrastructure components to the broader transportation network.

9. The Effect of the Finite Element Mesh Size on Fretting Fatigue Life Predictions

   Eduardo Fontes do Rêgo, Antonio Carlos de Oliveira Miranda, Scott Walbridge

   Abstract

   The objective of this work is to investigate the effect of the mesh size on the fretting fatigue life predicted using a finite element (FE) model of a cylinder on a flat surface under cyclic load. The mesh sizes evaluated are 5, 10, 20, and 30 µm at stress ratios of 0.1 and 0.5. Linear elastic fracture mechanics (LEFM) is applied to compute the fatigue life, in which the material properties of the aluminum 7075-T651 are input data. The stresses along the crack path are obtained using the FE software ABAQUS. The stress concentration due to the fretting condition is taken into account by the stress gradient factor (\(k_{{{\text{gr}}}}\)). A geometrical factor is computed using weight functions. Compared to the fatigue life computed using a mesh of 5 µm, the results show that an increase in the mesh size slightly increases the fatigue life. A decrease in initial crack length significantly increases the predicted fatigue life.

10. Bond Stress-Slip Behaviour of Carbon Fibre Reinforced Polymer (CFRP) Anchors of Varying Geometries Under Direct Pullout Conditions

    Dawit D. Sheferaw, Mark F. Green

    Abstract

    Ultra-High Performance Concrete (UHPC) is currently being considered for the construction of double wythe building wall panels, consisting of insulation sandwiched between two thin UHPC wythes. To enhance the structural performance of the panels, the two wythes need to be connected structurally, and composites are an excellent choice to avoid thermal bridging that can occur with metallic connectors. For the connectors to be effective, the bond between the connector and the UHPC is critical. Several studies have been conducted on the bond-slip behaviour of glass fibre reinforced polymer (GFRP) and carbon FRP (CFRP) bars in UHPC, but little effort has been directed towards studying the bond strength of CFRP composites fabricated from sheets. In this study, the tensile strength and bond-slip/anchorage behaviour of unidirectional CFRP sheets in UHPC are investigated. The sheets are formed into several types of anchors. Two main parameters, fibre content in UHPC and geometrical shape of CFRP sheets, are considered for this experimental investigation. UHPC mixes with 2% steel fibre and 2% POM fibre content are studied. The other four variable parameters (geometrical orientation) are CFRP sheets in straight, circular, round, and weave patterns. In total, 48 pullout specimens are fabricated and tested. The results of pullout test in specimens with anchors indicate that most of the anchors provide sufficient anchorage strength to allow tensile failure within the CFRP bars rather than anchorage failure/pullout failure. However, straight and weave patterns are not as effective, and the specimens fail with pullout and neck softening failure modes.

11. Seismic Performance of Precast Column-Footing Socket Connections: Development and Multi-scale Validation of a Numerical Model

    Chanh Nien Luong, Cancan Yang, Mohamed Ezzeldin

    Abstract

    The use of precast concrete elements and systems is becoming increasingly popular in bridge construction for their role in facilitating Accelerated Bridge Construction (ABC). Socket connections, a form of connection that emulates cast-in-place construction (CIP), are garnering interest for their rapid assembly, high installation tolerance, and construction ease. Research has shown that socket connections are viable for seismic applications, offering similar seismic performance to CIP counterparts. Despite this, their use in seismically active areas is limited due to the absence of an effective numerical model to simulate their seismic behavior. To address this challenge, the objective of this study is to create a nonlinear finite-element model (FEM) that simulates the behavior of socket connections between spread footings and precast columns under both gravity and seismic loads. In this respect, a new modeling technique is adopted to simulate the sliding mechanism of socket connection using equivalent beam elements. Connection-level test result is used to validate the accuracy of the FEM. The validated model is utilized to investigate the effect of different modeling techniques on the seismic behavior and local damage of socket connection in the component-level specimen.

12. Bridge Weigh-in-Motion: Localized Strain Response for Event Detection and Localization with Multiple Presence

    Jeremy Bowmaster, Kaveh Arjomandi, Diego Padilha

    Abstract

    Bridge Weigh-in-Motion systems can be effective in monitoring overweight traffic; however, with systems that utilize localized strain, that effectiveness is reduced in structures with high dynamic characteristics in the same frequency range as axle information. While this is widely acknowledged, dynamic effects coupled with sub-optimal sensor placement and driving behaviour, especially with multiple vehicles on the structure present a significant challenge to cluster data for classification. This paper examines signal characteristics of localized strain measurements from an operational BWIM system installed on a two-lane, single span, slab-on-girder, concrete highway bridge servicing an arterial class roadway. A large number of loading events were extracted from continuous data and verified using photographic ground truth. The events were categorized and labelled and peak amplitude values for localized strain were compared across FAD sensors. Feasibility of detecting single and multi-vehicle events and predicting lane position is discussed.

13. Seismic Design and Performance Evaluation of Post-tensioned CLT Shear Walls Coupled with U-shaped Flexural Plates

    Huanru Zhu, Matiyas A. Bezabeh, Asif Iqbal, Marjan Popovski, Zhiyong Chen

    Abstract

    Post-tensioned cross-laminated timber (PT-CLT) walls coupled with U-shaped Flexural Plates (UFPs) have proved to be a low-damage seismic force-resisting system (SFRS) due to their self-centring capability and enhanced energy dissipation. However, a comprehensive study is yet to examine their seismic performance in regions with high seismicity and complex seismotectonics. This paper assessed the seismic performance of PT-CLT shear wall buildings with UFPs. Three-, six-, and nine-storey prototype buildings were designed based on the direct displacement-based design (DDBD) method and seismic hazard in Vancouver, Canada. The assessment considered the most recent seismic hazard model provided in the 2020 National Building Code of Canada (NBCC). Two-dimensional fibre-based numerical models were developed and validated at the component-, system-, and building-levels. Nonlinear response history analyses were carried out to assess the structural responses and validate the DDBD procedure. Incremental dynamic analyses were conducted to examine the buildings’ collapse capacity, using 80 ground motions that were selected for each building and scaled to each seismotectonic regime’s Conditional Spectrum. The IDA results demonstrate that all the studied buildings have adequate collapse margin ratios, with less than a 10% chance of collapse at maximum considered earthquake events.

14. Digital Representation of Unreinforced Masonry Walls with Openings via an Efficient Algorithm for Structural Analysis

    Peter Griesbach, Andrei Farcasiu, Rhea Wilson, Bora Pulatsu

    Abstract

    This study proposes an efficient workflow for generating accurate discrete rigid block models of unreinforced masonry (URM) walls with openings from vision-based data. The proposed methodology uses AI-assisted object detection to identify the masonry units within an image of a target wall section (− 1 × 1 m). Statistical masonry texture characteristics (e.g., unit size distribution) and a masonry quality index parameter (e.g., vertical joint alignment) are automatically extracted and applied to generate a digital representation of the target wall. From this information, discrete blocks representing the expanded masonry units are generated row by row and used within the discrete element method (DEM) framework. The proposed workflow is applied to create a digital model of a URM wall in Kemptville, Ontario, Canada. A pushover analysis is performed in DEM, and the predicted failure mechanisms are used to complete an additional macro-block analysis. The results of this study demonstrate the potential of the proposed pipeline, which is shown to successfully capture the meso-scale texture and construction quality of the selected masonry façade. Emphasis is given to accurately representing the masonry wall texture and the “as-is” (or in situ) configuration in the adopted discontinuum-based computational modeling strategy. Therefore, the proposed workflow presents an efficient and accurate alternative to conventional CAD-based drafting techniques.

15. Blast Hardening of Reinforced Concrete Columns by External Post-tensioning

    Abdul Saboor Karzad, Muslim Majeed, Gamal Elnabelsya, Emre Insel, Murat Saatcioglu

    Abstract

    The design of blast-resistant civilian structures is not a common practice because blast is a rare event to occur. However, the rising concern from the increased number of terrorist attacks targeting civilian facilities triggered new challenges and accelerated the need for designing and building blast-resistant structures. Columns are critical structural elements, and loss of a column can trigger progressive collapse of the building. Protecting building columns through hardening can significantly improve the structure’s resistance to blast loads. The current research aims to address blast risk of reinforced concrete (RC) columns and potential improvements in their response by developing an innovative hardening technique. The experimental part of the study involves designing, building, and testing four half-scale RC columns that are hardened by externally anchored longitudinal prestressing seven-wire strands. The strands are anchored to the columns with three different longitudinal profiles: single harped, double harped, and triple harped or parabolic. A reference column and three hardened columns were tested under blast-induced shock waves generated by a blast simulator (shock tube). The test results included reflected pressure and impulse, maximum deflection, support reactions, and qualitative assessment of the level of damage. The results indicated that the behavior of hardened columns was significantly improved compared to the reference column. It was concluded that, on average the hardened columns could resist 20% higher reflected pressure and 40% higher impulse compared to the reference column before the onset of damage or failure. Moreover, in comparison with the reference column, the maximum deflection was noticeably lower in the hardened columns at each corresponding blast shot.

16. Expanding the Application of Recycled Concrete Aggregates for Road Construction

    Rahma Dhemaied, Ahmed Soliman, A. Lotfy

    Abstract

    Regarding high natural resource consumption, pavements are considered one of the highest-cost crucial infrastructures. Implementing recycled concrete aggregates (RCAs) in pavements promotes a path toward boosting economic, societal, and environmental sustainability. RCA is considered a multifaceted solution by preserving natural resources, minimizing pavement construction costs, and limiting harmful emissions. It has been found that RCA can be applied efficiently across different pavement layers, including base, sub-base, and surface layers. It is also observed that RCA’s mechanical and physical properties can be scrutinized and compared to natural aggregate properties. In addition, several techniques have been highlighted to enhance the performance of RCA in pavements. Although RCA can be recognized as a viable and sustainable alternative to natural aggregate (NA) in paving applications, recommendations regarding replacement rates in asphalt mixtures still vary significantly. RCA’s continued encouragement of implementation depends on in-depth research to unified and homogenous set of standards and specifications to balance the sustainability, functionality, and quality of pavements. This paper underscores the role of RCA as a critical driver for sustainable road construction and, therefore, a circular economy strategy.

17. The Behaviour of Ribbed GFRP-Reinforced Concrete Beam Under Fatigue

    Islam Elsayed Nagy, Alireza Asadian, Khaled Galal

    Abstract

    Although glass fibre-reinforced polymer (GFRP) is increasingly being used as a substitute for steel reinforcements, there is a lack of studies on the fatigue performance of GFRP bars in reinforced concrete structures. This study examines the fatigue life of ribbed GFRP bars in concrete beams. The experimental program is set to test a concrete beam reinforced with GFRP under fatigue loading. The maximum fatigue tension stresses applied on the GFRP bars are designed to be 30% of the ultimate tensile strength (UTS). The paper also presents a testing methodology employing a displacement-controlled system for fatigue testing. This protocol specifically solves many problems related to force-controlled fatigue testing. This research indicates that ribbed GFRP bars can endure two million cycles of fatigue loading without failure, where the GFRP bars were under 30% of the UTS, with a stress ratio of 40%. The fatigue life achieved surpasses the results reported in previous studies, highlighting the influence of stress ratio and bar surface profile on fatigue performance.

18. Seismic Safety Analysis of Small Modular Reactors (SMRs): A Hybrid BEM–FEM Approach

    Min Basnet, Zarghaam Rizvi, Dipanjan Basu, Frank Wuttke

    Abstract

    Seismic analysis of small and medium nuclear reactor (SMR) plants is of utmost importance for their safe design and operation. Terrain effect, which is often neglected in traditional analysis approaches, is one of the important parameters for site-specific seismic characterization. A hybrid boundary/finite element method (BEM–FEM) is applied to account for the seismic response of nuclear power plants in a rugged terrain. A 3D hybrid BEM–FEM model of a pair of nuclear power plants located in the footstep of a mountainous region is developed. The boundary element method (BEM) is used to model the far-field irregular topography. Finite element method (FEM) is used to model the near-field soil, foundation, and the superstructure of the main and auxiliary buildings of the nuclear power plant. The analytical expression for time-harmonic free-field motion is used to simulate the incident seismic wavefield. The results include the seismic responses of the two nuclear power plant structures that account for the terrain effects.