Civil and Environmental Engineering Commons^™

Ndm-552: Combined Probabilities Of Peak Wind And Snow Load Events, Jill V. Bond, Albert J. Brooks, Scott L. Gamble, Jan C. Dale

Canadian Society for Civil Engineering

The National Building Code of Canada 2010 (NBCC) defines several loading combination scenarios for use in structural design. Appropriate combination factors are provided based on the probability of failure due to the simultaneous occurrence of the specified loads. Load Combination Cases 3 and 4 of Table 4.1.3.2.A include the combination of wind and snow loads, which are transient in nature. The recommended combination factors are intended to provide a uniform degree of reliability for design. However, in reality, the probability of the simultaneous loading due to wind and snow depends on the local meteorological climate. This probability can be more …

Ndm-555: Experimental Investigations Of Large Scale Tld-Structure Interaction Via Real-Time Hybrid Simulation, Ali Ashasi-Sorkhabi, Oya Mercan

Canadian Society for Civil Engineering

In real-time hybrid simulation (RTHS), as a cost-effective experimental testing technique, computer simulations are coupled with physical testing. RTHS divides the test structure into analytical and experimental substructures, and synchronizes them as the equations of motion are being solved in real-time. When conducted properly, the load-rate dependent characteristics of the test structure could be accurately captured by the RTHS. This paper presents real-time hybrid simulation of a three story structure equipped with a large scale tuned liquid damper (TLD) using a recently developed computational/control platform at University of Toronto. TLDs are cost effective and low maintenance vibration absorbers that can …

Ndm-556: Wind Uplift Resistance Design Of A Green Roof, Mike Gibbons, Scott L. Gamble, J. Shayne Love

Canadian Society for Civil Engineering

Green roofs, also referred to as vegetated roofs, have increased in popularity in recent years in North America. Traditionally their use had been more prominent in European countries, such as Germany, however the North American design community have recently adopted them, thanks in part to programs such as LEED and the City of Toronto’s Green Roof Bylaw. Toronto’s Green Roof Bylaw mandates “green roofs on new commercial, institutional and residential development with a minimum Gross Floor Area of 2,000m2 as of January 31, 2010”. Also contained within the aforementioned Green Roof Bylaw is a requirement that the submitted green roof …

Ndm-557: Computational Modeling Of Hill Effects On Tornado Like Vortex, Zoheb Nasir, Girma T. Bitsuamlak

Canadian Society for Civil Engineering

Tornado is a complex flow structure, where high swirling flow closer to the ground converges to the center and then moves upward. As a result, it creates a high suction pressure at the ground near the center of the tornado. The main objective of this study is to analyse the impact over flow structure and ground pressure by implementing topographical changes. For the present study a one-celled tornado replicating a real EF-2 scale has been chosen. Previous study suggests that suction ground pressure is highest at the tornado core center, also it changes more sharply near the core center. As …

Ndm-558: Computational Modeling Of Tornadic Load On A Tall Building, Zoheb Nasir, Girma T. Bitsuamlak

Canadian Society for Civil Engineering

Numerical simulations are carried out to analyse the impact of tornadic load on a tall building. For the present study a one-celled tornado replicating a real EF-2 scale has adopted. A standard tall building based on the Commonwealth Advisory Aeronautical Research Council (CAARC) is used. For detail analysis, the tornado is placed in three different locations with respect to the center of the building. These locations are at the tornado center, at the core radii and outside core radii. As the building has rectangular cross section (plan wise), two different orientation of the building with respect to the center of …

Ndm-559: Experimental Investigation Of Two-Way Concrete Panels Exposed To Impact Load, Heba G. S. Bayoumy, Mohamed A. N. Abdel-Mooty, A. Samer Ezeldin

Canadian Society for Civil Engineering

Protecting existing and new structures from potential terrorist attacks and accidents is becoming an essential consideration in the design of most structures. Building façade is the first layer exposed to external loading, thus it acts as the first line of defence against external loads. Precast concrete panels are mostly used in external building's façade for modern construction, and therefore their resistance to other dynamic loads such as impact load needs further evaluation. This paper presents the results of an experimental research on two-way reinforced concrete panels as well as thin ferrocement concrete panels under impact loading. The impact test apparatus …

Ndm-561: Municipal Risk Assessment Tool (Mrat), Scott Praill

Canadian Society for Civil Engineering

MRAT is a made-in-Canada tool that overlays municipal data sets and insurance claims data onto an interactive map. The tool allows infrastructure managers to accurately identify areas with frequent insurance claims and easily identify where a more in-depth assessment should occur. The tool facilitates an understanding of risk factors to potentially impacted areas allowing owners to start to diagnose problems and generate solutions before flooding occurs. The process began with an original objective that would identify areas where there are an increased number of insurance claims. Early in its development, it became obvious that it could be a valuable tool …

Ndm-562: Behaviour Of Concrete Columns With Gfrp Circular And Rectilinear Confining Reinforcement, Zahra Kharal, Shamim A. Sheikh

Canadian Society for Civil Engineering

Glass Fibre-Reinforced Polymer (GFRP) bars are becoming a feasible alternative to steel bars to produce corrosion- free reinforced concrete structures. In an effort to assess the effectiveness GFRP spirals and GFRP rectilinear ties as internal reinforcement in columns, an extensive research program is underway at the University of Toronto. Fifteen 356 mm diameter full-scale circular columns and sixteen 305 mm x 305 mm cross-section square columns were constructed and tested under simulated earthquake loading. This extended abstract presents an example comparison of the experimental behaviour of circular and square concrete columns with internal reinforcement comprising of steel longitudinal bars and …

Ndm-563: The Vertical, Rotational And Lateral Response Of Unbonded Fiber Reinforced Elastomeric Isolators, Yasser M. Al-Anany, Michael J. Tait, Mark Torrie, Alexander N. Sciascetti

Canadian Society for Civil Engineering

Bridge structures often experience damage during an earthquake, which is one of the most devastating types of natural disasters. Base isolation can be employed to mitigate earthquake-induced damage. The main concept of base isolation is to reduce the seismic demand on the structure by shifting its fundamental time period away from the predominant periods associate with earthquakes. Base isolation involves placing horizontally flexible isolators between the bridge superstructure (i.e. deck/girder) and the substructure (i.e. pier/column). There are two main types of seismic isolators: (1) elastomeric, and (2) sliding. A fiber reinforced elastomeric isolator (FREI) is a particular type of reinforced …

Str-805: Experimental Evaluation Of The Robustness Of Wt Connections Under Quasi-Dynamic Load, Megan E. Hayes, Christopher H. Raebel, Christopher M. Foley

Canadian Society for Civil Engineering

Flexible (simple) shear connections commonly used in steel-framed buildings are very economical and are relatively easy to fabricate. These connections are used for shear resistance, but recent studies have shown that they are capable of sustaining an interaction of rotational and axial load demand necessary for steel-framed building structures to help resist collapse in the event of unanticipated damage scenarios.

The objective of this paper is to outline and discuss an experimental effort designed to evaluate the robustness of flexible WT connections. The experimental program included twelve full-scale tests of a system consisting of two wide flange beams connected to …

Str-806: Experimental Evaluation Of The Robustness Of Single Plate Shear Connections Under Quasi-Dynamic Load, Jacklyn E. Lesser, Christopher H. Raebel, Christopher M. Foley

Canadian Society for Civil Engineering

Flexible (simple) shear connections commonly used in steel-framed buildings are very economical and are relatively easy to fabricate. These connections are used for shear resistance, but recent studies have shown that they are capable of sustaining an interaction of rotational and axial load demand necessary for steel-framed building structures to help resist collapse in the event of unanticipated damage scenarios.

The objective of this paper is to outline and discuss an experimental effort designed to evaluate the robustness of single plate shear connections under a quasi-dynamic loading scenario simulating the loss of a central column. The experimental program included eleven …

Str-807: Ansys Modeling Of Post-Tensioned Steel Beam-Column Connections Under Cyclic Loading, Saber Moradi, M. Shahria Alam

Canadian Society for Civil Engineering

Permanent deformations in a steel moment resisting frame can be eliminated by using post-tensioned (PT) elements. This paper presents the development of three-dimensional finite element models of PT steel beam-column connection subassemblies. Knowing that there is limited experimental data in the literature on PT steel connections with top-and-seat angles, reliable finite element models can be used to investigate the load carrying behaviour of PT steel connections as well as producing more data for these new connections. In this paper, finite element modelling, meshing, and analysis are performed in the commercial software, ANSYS. The analysis includes geometric and material nonlinearities, pre-loaded …

Str-808: Re-Testing Of A Fire-Damaged Bridge, Alexander M. C. Au

Canadian Society for Civil Engineering

A proof load test was performed on a fire-damaged bridge in October 2008 and its load capacity was confirmed. The bridge was then re-opened for full traffic shortly after the load test. It was further repaired in 2009 which included concrete patching and carbon fibre reinforced polymer (CFRP) warping of 6 girders in the main span. The bridge is located at one of the busiest highways of the country with many heavy trucks passing daily. Also, reinforced concrete could deteriorate much faster than usual after the fire accident. In 2014, the Bridge Office was requested to re-test the bridge in …

Str-810: A Formulated Approach To Cisc Shear Connection Resistance And Flexibility Design, Josiah J. Matthews, Kaveh Arjomandi

Canadian Society for Civil Engineering

The design of simple shear connections has been extensively studied by several researchers. The design requirements for ductility and strength of these connections have been established through both experimental and theoretical approaches. However, the current Canadian design guidelines such as the Handbook of Steel Construction published by the Canadian Institute of Steel Construction (CISC) do not provide a formulated approach for the design of shear connections. In addition, the CISC design approach is somewhat out dated when it comes to providing adequate rotational ductility. In this paper, a formulated approach for the design of bolted double angle shear connections considering …

Str-811: Examination Of Effective Length Factor For Rc Columns In Non-Sway Frames, S. Ali Mirza, Timo K. Tikka

Canadian Society for Civil Engineering

The Canadian Standards Association (CSA) Standard for Design of Concrete Structures (A23.3-04) permits the use of moment magnifier method for computing the design ultimate strength of slender reinforced concrete (RC) columns that are part of non-sway frames. This computed strength is influenced by the column effective length factor K, effective flexural stiffness EI, and equivalent uniform bending moment diagram factor Cm among others. Previous investigations by the authors examined the equations available in literature for computing EI and Cm factor. For this study, nearly 3000 simple non-sway reinforced concrete frames subjected to short-term loads were simulated and used to investigate …

Str-813: Fragility Of Low-Rise Controlled Rocking Steel Braced Frames With Different Base Rocking Joints, Taylor C. Steele, Lydell D. A. Wiebe

Canadian Society for Civil Engineering

Controlled rocking steel braced frames (CRSBFs) are resilient seismic force resisting systems that can self-centre the structure and prevent structural damage during design-level earthquakes. Energy dissipation may be provided to limit peak displacements, while post-tensioning provides self-centering after rocking. Previous studies have shown that designing energy dissipation and the post-tensioning components in CRSBFs using a response modification factor of R = 8 is sufficient to prevent collapse of structures during earthquakes higher than the design level. However, designers have unique control over the hysteretic behaviour of the system, even after the response modification factor is selected. Additionally, recent studies have …

Str-814: Lessons Learned From The Nairn Avenue Overpass Concrete Girder & Pier Repairs, David A. Neilson, Darren Burmey, Scott Loptson

Canadian Society for Civil Engineering

The Nairn Avenue Overpass is a 213 m long, 11-span, 4-lane + sidewalk precast prestressed concrete I-girder bridge over the CP Keewatin Subdivision line in Winnipeg, MB. The superstructure consists of three continuous segments with deck joints at piers #3 and #8. The structure was built in 1967, and underwent major strengthening and rehabilitation of the deck, girders, and bearings in 1985. Piers consist of a cast-in-place pier cap approximately 18 m long supported on two cast-in-place columns approximately 7 to 8 m tall supported on concrete pile caps over timber raft-pile foundations.

Leaking omega-style strip seal deck joints at …

Str-815: Feasibility Of Using Unbonded Reinforcement In Concrete Block Walls, Henry Miranda, Lisa R. Feldman, Bruce F. Sparling

Canadian Society for Civil Engineering

An experimental program is underway at the University of Saskatchewan to investigate the performance of concrete masonry block walls reinforced with non-prestressed, unbonded reinforcement that are subjected to out-of-plane lateral loads. By eliminating the need for grouting, this construction method may lead to substantially lower wall weights, as well reduced construction times, cost, and workplace injuries. At the same time, the presence of reinforcement will increase the flexural strength of the walls, significantly increasing the allowable vertical spans of such walls as compared to those of comparable unreinforced walls. Unreinforced walls, as well as conventionally reinforced and partially grouted walls, …

Str-816: The Rio Abajo Footbridge: Promoting Development Through The Use Of Resilient Infrastructure, Hendrik Westerink, Alan Kreisa

Canadian Society for Civil Engineering

In the remote farmlands of the developing world, walking is the primary form of transportation. When rivers flood during the rainy season, walks to school, work or the doctor can become life threatening without a bridge to cross. For hundreds of millions of people worldwide, rural isolation caused by a shortage of safe river crossings is a significant impediment to economic development and self-sufficiency. Non-profit organization Bridges to Prosperity (B2P) works with vulnerable communities to build footbridges that create year-round access to essential services. Data describing flood and wind events is often not available in the rural areas of the …

Str-817: The Deck Replacement Of The Honore-Mercier Bridge. An Innovative Solution Using Accelerated Bridge Construction Techniques, Adel R. Zaki, Steve Tselios

Canadian Society for Civil Engineering

Today, the Honoré-Mercier Bridge crosses the St. Lawrence River and the seaway on the west side of the Island of Montreal. Named after the Honorable Honoré-Mercier, a former Premier of Quebec, this bridge became the fourth structure to connect the Island of Montreal to the South Shore. The entire steel structure was built by the Dominion Bridge Company Limited as part of work funded by the government to address the economic downturn. The Honoré-Mercier Bridge was inaugurated 10 months earlier than planned on June 22, 1934, and initially belonged to the Corporation du pont du Lac Saint-Louis. It's administration was …

Str-818: The Effect Of Relaxation On The Slip Resistance Of Metallized Faying Surfaces In Slip-Critical Connections, Maxime Ampleman, Charles-Darwin Annan, Mario Fafard, Éric Lévesque

Canadian Society for Civil Engineering

Metallizing has emerged as an effective protective coating for steel bridge members, providing a physical barrier and a galvanic protection. Recent research has shown that metallized faying surfaces used in high strength bolted connections provide higher slip resistance than specified values for uncoated blast-cleaned faying surfaces in North American design standards. As a particularity, relaxation of the clamping force is observed in the slip-critical connections with metallized faying surfaces. In this study, tests were designed to evaluate the effect of relaxation on the slip resistance of metallized faying surfaces in high strength bolted connections. Some design parameters included in this …

Str-823: Flexural Behaviour And Bond-Dependent Coefficient Of Basalt Frp Bars In Concrete Beams, Fareed Elgabbas, Ehab Ahmed, Brahim Benmokrane

Canadian Society for Civil Engineering

This paper presents an experimental study aimed at determining the bond-dependent coefficient (kb) and investigating the flexural performance of concrete beams reinforced with ribbed basalt fiber-reinforced polymer (BFRP) bars. The performance of the BFRP-RC concrete beams is compared against that of GFRP-RC ones. A total of five concrete beams measured 200 mm wide × 300 mm deep × 3100 mm long were constructed and tested in four-point bending over a clear span of 2700 mm. The main variables were reinforcement type (BFRP, GFRP, and steel bars as reference) and reinforcement ratio. The test results showed that the average kb was …

Str-824: Fatigue Behavior Of Concrete Underground Chambers Reinforced With Gfrp Bars, Michaël Guérin, Hamdy M. Mohamed, Brahim Benmokrane

Canadian Society for Civil Engineering

Precast underground concrete chambers reinforced with steel bars are used frequently in construction and electrical industry for housing power cables and transformers. In Quebec, more than 30,000 of these chambers have been installed by Hydro-Quebec during the last 30 years. However, like other conventionally reinforced concrete structures, corrosion of steel reinforcement constitutes the major cause of chambers deterioration, leading to costly repairs and rehabilitation as well as a significant reduction in service life. This paper presents experimental data on the fatigue and static behavior of full-scale underground concrete chamber reinforced totally with glass fiber-reinforced polymer (GFRP) bars. The chamber measure …

Str-827: Shear Strength Of Circular Concrete Beams Reinforced With Gfrp Bars, Ahmed H. Ali, Hamdy M. Mohamed, Brahim Benmokrane

Canadian Society for Civil Engineering

This paper presents the results of an investigation of the shear strength and behavior of three circular concrete beams reinforced with glass-FRP (GFRP) bars and spirals. The beams, which measured 3,000 mm in length by 500 mm in diameter, were tested under four-point bending. The test parameters included the GFRP-spiral-reinforcement ratio (different spiral spacings [150 and 200 mm] and spiral diameters [13 and 15 mm]). As designed, the beams failed in shear due to GFRP-spiral rupture. The test results indicated that the higher the GFRP spiral reinforcement ratio, the higher the enhancement of the shear strength due to the confinement, …

Str-828: Behavior Of Circular Frp-Reinforced Concrete Columns Under Eccentric Loading, Abdeldayem Hadhood, Hamdy M. Mohamed, Brahim Benmokrane

Canadian Society for Civil Engineering

This paper presents the results of an investigation of the eccentric compression behavior of three full-scale circular concrete columns reinforced with the glass-fiber-reinforced polymer (GFRP) bars and spirals. The column specimens measured 1500 mm height, 305 mm diameter and were tested under monotonic eccentric loading. The main variable was the eccentricity-to-dimeter ratio. Three values were considered in this study (8.20%, 16.39%, and 65.57%). The failure mechanism was changeable according to the level of the applied eccentricity. The failure mechanism of columns at small eccentric loading was defined as compression-controlled due to concrete crushing. At high eccentric loading, the failure of …

Str-829: Behavior Of Gfrp-Reinforced Concrete Squat Walls Under Simulated Earthquake Loading, Ahmed Arafa, Ahmed Sabry Farghaly, Brahim Benmokrane

Canadian Society for Civil Engineering

Steel-reinforced squat walls are used as the main component for earthquake resistance in low-rise structures. Deterioration due to corrosion of steel reinforcement is one of the major challenges facing the construction industry. Furthermore, given the low aspect ratio of squat walls, their behavior is dominated by inelastic shear deformations activated by the yielding of flexural reinforcement. These deformations degrade strength and stiffness with subsequent shear failure, preventing the wall from achieving its flexural capacity, which is a prerequisite for adequate seismic design. Using noncorrodible glass-fiber-reinforced-polymer (GFRP) bars represents an effective method for overcoming corrosion problems. In addition, the available experimental …

Str-830: Enhancing The Deformation Capacity Of Concrete Shear Walls Reinforced With Gfrp Bars, Ahmed Hassanein, Nayera Mohamed, Ahmed Sabry Farghaly, Brahim Benmokrane

Canadian Society for Civil Engineering

An experimental study was recently conducted to address the applicability of concrete shear walls entirely reinforced with glass-fiber-reinforced polymer (GFRP) bars and subjected to quasi-static reversed cyclic lateral loading in attaining reasonable strength and drift requirements specified in different codes. The reported test results clearly show that properly designed and detailed GFRP-reinforced concrete (RC) walls could reach their flexural capacities with no strength degradation. The results also demonstrate that the tested walls were able to achieve recoverable and self-centering behavior up to allowable drift limits before experiencing moderate damage and attain a maximum drift comparable to steel-RC walls. The promising …

Str-831: Fatigue Strength Of Angle-Shaped Transverse Connection For Gfrp-Reinforced Precast Full-Depth Deck Panels In Accelerated Bridge Construction, Mahmoud Sayed-Ahmed, Khaled Sennah

Canadian Society for Civil Engineering

Prefabricated bridges elements and systems (PBES) are subjected to repeated truck loads while being exposed to weather conditions. Fatigue of the structural elements and corrosion of the reinforcement are the main reasons for bridge deterioration. This research investigates the fatigue strength of full-depth deck panels (FDDP) resting over steel cross-braced girders and reinforced with ribbed-surface, high-modulus (HM), glass fiber reinforced polymer (GFRP) bars. The precast FDDP has transverse panel-to-panel connection of angle-shape with female shear key, and panel-to-girder connection of V-shape, where both connections are filled with ultra-high performance fiber reinforced concrete (UHPFRC). Two different fatigue loading were conducted to …

Str-832: Ultimate Flexural Strength And Long-Term Creep Deflection For Structural Insulated Foam-Timber Sandwich Panels, Mahmoud Sayed-Ahmed, Khaled Sennah, Ahmed Diab, Sherif Mansour

Canadian Society for Civil Engineering

The structural insulated panel (SIP) is a sandwich structured composite that is prefabricated by attaching a lightweight thick core made of Expanded Polystyrene (EPS) foam laminated between two thin, and stiff face skins made of Oriented Strand Board (OSB). The use of sandwich panels provides key benefits over conventional materials including: very low weight; high stiffness; durability and; production and construction cost savings. The facing skins of the sandwich panel can be considered as the flanges for the I-beam carrying bending stresses in which one face skin is subjected to tension, and the other is in compression. The core resists …

Str-833: Evaluation Of The Contribution Of Panel Zones To The Global Performance Of Moment Resisting Frames Under Seismic Load, Paul Steneker, Lydell D. A. Wiebe

Canadian Society for Civil Engineering

Before the 1994 Northridge Earthquake, the seismic design strategy for moment resisting frames considered the yielding of the panel zone when calculating the required level of ductility. Following the unacceptable performance of conventional moment resisting frame (MRF) connection details during the Northridge seismic event, prequalified connections were developed to concentrate beam yielding away from the column face, preserving the connection. With these new connection strategies, the panel zone deformation may not contribute as significantly to the overall behaviour of an MRF. Therefore, considering the increased use of advanced dynamic modeling techniques, it is important for both designers and researchers to …