Construction Engineering and Management Commons^™

Experimental Modal Analysis And Seismic Mitigation Of Statue-Pedestal Systems, Christine E. Wittich, Tara C. Hutchinson

Department of Civil and Environmental Engineering: Faculty Publications

The seismic protection of cultural heritage, particularly statues, is a critical issue due to its high cultural significance, difficulty to repair or replace artifacts, and observed poor behavior during past earthquakes. Recent research has explored analysis techniques and methodologies for predicting the seismic response of statues; however, these studies typically assume the statue to be either freestanding or rigidly attached. The seismic response of statues with these different boundary conditions varies widely and therefore accurate characterization is critical. While modern mounting techniques aim to rigidly attach a statue to the floor or to a pedestal, the degree of rigidity of …

Bs News July/August

Building Services Engineering

No abstract provided.

Wartime Construction Project Outcomes As A Function Of Contract Type, Ryan M. Hoff, Gregory D. Hammond, Peter P. Feng, Edward D. White

Faculty Publications

The United States has spent more than $23 billion on construction in Afghanistan since 2001. The dynamic security situation created substantial project uncertainty, and many construction projects used cost-plus-fixed-fee contracts (CPFF) instead of the firm-fixed-price (FFP) norm. Using a dataset of 25 wartime construction projects managed by the Air Force Civil Engineer Center, the authors sought to confirm that both contract types yield project outcomes consistent with the established literature. As expected, they found CPFF contracts had greater cost and schedule growth than FFP. However, they did not find differences regarding as-built quality. Additionally, the authors sought to determine whether …

Engineered Earthen Masonry Structures For Extreme Wind Loads, Mabel Cristina Cuellar-Azcarate

Theses and Dissertations

Stabilized earthen masonry (SEM), which is built with compressed stabilized earthen blocks (CSEB) and mortar, is emerging as a construction system for affordable, sustainable and high-quality dwellings. Compelling features of earthen masonry are local availability of suitable soils, thermal insulation properties, humidity control within healthy ranges, and relatively low carbon footprint. SEM is also appealing for the construction of affordable houses in rural areas and farmlands, where underrepresented and underprivileged groups often live. In fact, the lack of affordable housing is an issue across the United States where low-income families are most affected, often committing more than half of their …

Optimization Of Air Entrained Grout Enriched Roller Compacted Concrete For Improving Freeze-Thaw Resistance Of Hydraulic Structures, E. S. Musselman, R. J. Flynn, G. J. Zimmer, J. R. Young Pe

International Symposium on Hydraulic Structures

Roller compacted concrete (RCC) is frequently used to construct gravity dams, stepped spillways, and to armor earthen embankments for passing extreme floods. Early experience on RCC dam applications in the 1980s showed a tendency for seepage to develop along the lift lines. Therefore, RCC dam designers started including an upstream facing system as a watertight barrier. An alternative facing material that has been used extensively overseas and is starting to gain more widespread acceptance in the United States is Grout Enriched RCC (GERCC). The grout enriched method of face construction has been shown to be less expensive than other facing …

Decision-Making Through Sustainability, F. Pardo-Bosch, A. Aguado

International Symposium on Hydraulic Structures

From immemorial time, dams have contributed significantly for the progress of civilizations. For this reason, nowadays, there is a vast engineering heritage. Over the years, these infrastructures can present some ordinary maintenance issues associated with their normal operation or with ageing processes.

Normally, these problems do not represent an important risk for the structure, but they have to be attended. To do it, owners of dams have to finance many ordinary interventions. As it is impossible to carry out all of them at the same time, managers have to make a decision and select the most “important” ones. However, it …

An Investigation In Construction Cost Estimation Using A Monte Carlo Simulation, Jeffrey D. Buchholtz

Theses and Dissertations

The Air Force estimates military construction (MILCON) costs early in a project’s development as a part of the funding approval process. However, many of the initial cost estimates deviate significantly more than expected from the actual project costs, hindering funding allocation efforts. There is a need for improved estimation techniques. This research examines a cost estimation model for the initial programming stages of a project when only general scope information is available.

This study develops a Monte Carlo simulation based on historical construction cost data to predict project costs base on facility type. For a given facility type, the research …

Corrosion Of Steel In Concrete And Its Prevention In Aggressive Chloride-Bearing Environments, Luca Bertolini, Maddalena Carsana, Matteo Gastaldi, Federica Lollini, Elena Redaelli

International Conference on Durability of Concrete Structures

This keynote paper deals with the durability of reinforced concrete (RC) structures exposed to aggressive environments characterized by high concentration of chloride ions, namely, marine environments or the use of de-icing salts. The mechanism of chloride-induced corrosion of steel in concrete is introduced, and its influence on the service life of RC structures is analyzed. Factors affecting the time to corrosion initiation are described with regard to both concrete properties and environmental exposure conditions. Design approaches available for achieving durability targets associated with the design service life are analyzed, focusing on studies carried out by the authors in recent years …

Mat-701: Predicting The Compressive Strength Of Ultra-Lightweight Concrete By An Artificial Neural Network, Jordan Ouellet, Jean-Luc Martel, Claudiane Ouellet-Plamondon, Alan Carter

Canadian Society for Civil Engineering

Ultra-lightweight concrete (ULWC) has potential applications for floating structures and architectural elements because of its dry density coming in at under 1000 kg/m3. The objective was to develop an artificial neural network (ANN) to aid the ULWC designer according to his needs. Boundary conditions were set for each material and 13 constraints based on the water binder ratio, density, air content, binder and aggregate content. The ANN predicted the compressive strength with a comfortable margin of error, with the gap encountered being attributed to variability in workability. Precise constraints and boundary conditions are needed to ensure a lower variability in …

Mat-702: Mechanical Behaviour Of Ultra-High Performance Concrete Obtained With Different Concrete Constituents And Mix Designs, Mahmoud Sayed-Ahmed, Khaled Sennah, Moulay Youssef Monsif

Canadian Society for Civil Engineering

This research investigates the mechanical behaviour for the Ultra-High Performance Concrete (UHPC) and UltraHigh Performance Fiber Reinforced Concrete (UHPFRC). UHPC and UHPFRC are designed to be self-consolidated concrete that level itself without mechanical vibration due to its highly flowability and moderate viscosity. UHPFRC is used as joint-fill cementitious materials for the connections of prefabricated bride elements and systems used for the Accelerated Bridge Construction and rapid bridge replacement. The main concrete constituents of such materials consist from: binders (cement), powders (fillers), liquids (additives), water, and fibers. Hence, the mixture proportion design should follow a densified mixture design algorithm to densify …

Mat-704: Resistance Of Concrete Incorporating Portland Limestone Cement To Sulfuric Acid, Mahmud Amin, Mohamed T. Bassuoni

Canadian Society for Civil Engineering

Concrete has long been the most popular choice for constructing key infrastructural elements such as sewer pipes, water treatment facilities, industrial floors and foundations. However, many field cases from all around the world have shown that concrete elements in these environments are severely damaged due to biogenic and/or chemical sulfuric acid attack. Since high alkalinity is required for the stability of the cementitious matrix, concrete is highly prone to acid attacks, which decalcify and disintegrate the hydrated cement paste to various levels based on exposure conditions and type of concrete. Numerous studies have been conducted to enhance the durability of …

Mat-705: Improving The Efficiency Of Zinc Sacrificial Anodes In Repaired Concrete, Ahmed G. Bediwy, Mohamed T. Bassuoni, Martin Beaudette

Canadian Society for Civil Engineering

Zinc sacrificial anodes are considered an effective and economical method to prevent the electrochemical corrosion of steel bars by providing cathodic current to bars, which can provide corrosion protection at low galvanic current densities in the range of 0.2 to 2 mA/m2. Sacrificial anodes are commonly used in RC structures particularly in bridge decks to mitigate a critical phenomenon that occurs in the original concrete beside the repaired patches, which is known as the ‘halo effect’. One of the key factors affecting the efficacy of zinc anodes is the resistivity of concrete or cementitious repair material in which these anodes …

Mat-707: Development Of Enhanced Test Methods To Evaluate Alkali-Silica Reaction In Concrete, Noura Sinno, Medhat Shehata

Canadian Society for Civil Engineering

The research presented in this paper studies the effect of sample geometry and temperature on expansion due to alkali-silica reaction (ASR) in concrete. Expansions of cubes and cylinders are compared to those of the standard prisms. Control samples, samples with fly ash (FA) and others with slag are investigated at two temperatures, 38°C and 60°C. At 38°C, results showed that smaller samples have higher expansion at early ages. However, larger samples such as cubes and cylinders seem to reach higher expansion compared to prisms after 32 weeks for both control and samples with fly ash. In addition, the results showed …

Mat-708: Monitoring The Corrosion Process Of Reinforced Concrete Flat Slab-Column Connection, Mahmoud E. Said, Amgad Hussein, Assem A. A. Hassan

Canadian Society for Civil Engineering

The corrosion of the steel reinforcement embedded in a two-way reinforced concrete flat slab around the column stub area was investigated in this study, which aimed to studying the effect of corrosion on the shear punching behavior. Two square flat slab-column connections were cast, the flat slab dimension was 1900 mm × 1900 mm × 150 mm, and the column dimensions was 250 mm × 250 mm. A specific delaminated area was corroded around the column stub to emphasize the effect of corrosion around punching area. The corrosion reached two levels of mass loss uniformly over that specified area: 0% …

Mat-711: Utilization Of Recycled Crumb Rubber In Structural Self-Consolidating Concrete, Mohamed K. Ismail, Assem A. A. Hassan, Madolyn A. Lundrigan

Canadian Society for Civil Engineering

The present work evaluates the impact of using recycled crumb rubber (CR) as a partial replacement of fine aggregate on the fresh and mechanical properties of concrete composite, especially when self-consolidating concrete is used. In this study, seven mixtures containing various amounts of fine CR (0-30% by volume of sand) were tested. The fresh properties tests included flowability, passing ability, and segregation resistance. On the other hand, the mechanical properties tests included compressive strength, modulus of elasticity, splitting tensile strength, and flexural strength. The results indicated that although increasing the CR replacement decreased the fresh and mechanical properties of concrete, …

Mat-712: Microstructural Investigations On The Self-Healing Ability Of Engineered Cementitious Composites Incorporating Different Mineral Admixtures, Ahmed Alyousif, Khandaker M. Anwar Hossain, Mohamed Lachemi, Mustafa Sahmaran

Canadian Society for Civil Engineering

The present study investigates the impacts that self-healing has on the microstructure characteristics of microcracked Engineered Cementitious Composites (ECC). These have two contrasting maturity levels and, furthermore, they involve three varying mineral admixtures that have very different chemical constituents. The impact of self-healing on the transport characteristics was examined by employing rapid chloride permeability tests (RCPT). The findings indicated that, if the appropriate mineral admixture type and conditioning were chosen, it would be possible to enhance the majority of the chloride ion penetrability levels following a 30-day period of water curing. As a result, the majority of the findings were …

Mat-713: Evaluation Of Ndt Techniques For Concrete Bridge Decks Using Fuzzy Analytical Hierarchy Process, Tarek Omar, Moncef L. Nehdi

Canadian Society for Civil Engineering

Considering the colossal backlog of deteriorating bridges, transportation agencies need to systematically evaluate bridge deck conditions in order to optimize the timing, scope, and approach of preventive maintenance, repair, and replacement. Over the last few years, there have been growing interest among bridge infrastructure stakeholders in using non-destructive methodologies for bridge inspection, evaluation, and maintenance. Nondestructive testing (NDT) techniques can provide needed information about the “under-the-surface” deteriorated condition of bridge decks. This paper examines the most common NDT technologies for assessing bridge decks. Each technology was rated based on five performance measures: capability to detect subsurface defects, speed of data …

Mat-714: Condition Assessment And Deterioration Prediction Tools For Concrete Bridges: A New Look, Tarek Omar, Moncef L. Nehdi

Canadian Society for Civil Engineering

Structural problems created by corrosion, ageing, aggressive environments, material defects and unforeseen mechanical or seismic loads can compromise the serviceability and safety of bridges. The importance of an effective bridge-management system (BMS) cannot be overstated, especially in light of the recent collapse of bridges in North America and elsewhere. Several technologies are available for assessing the condition of concrete bridges and a number of deterioration models are used to predict future bridge conditions and estimate associated funding requirements. This paper critically reviews the different available condition assessment and deterioration prediction approaches for concrete bridges. The potential applications of condition assessment …

Mat-716: Green Sidewalks Using Sustainable Two-Stage Concrete, Manal F. Najjar, Ahmed M. Soliman, Tareq M. Azabi, Moncef L. Nehdi

Canadian Society for Civil Engineering

Two-stage concrete (TSC) is a special type of concrete, which has a high potential for use in sidewalk construction owing to its high volume stability. TSC is characterized by its high coarse aggregate content. Hence, using recycled solid waste materials as a coarse aggregate will increase TSC sustainability, while providing a cost-effective alternative to natural aggregates. Aggregates are pre-placed in TSC. Hence, water absorption by recycled concrete aggregates and the associated rheology problems do not exist in TSC. This study explores the performance of green TSC sidewalks incorporating recycled concrete aggregates (RCA) and crumb rubber from scrap tires. Mechanical properties …

Mat-719: Investigation Of Grouted Precast Concrete Wall Connections At Subfreezing Conditions, Douglas James Provost-Smith, Mohamed Elsayed, Moncef L. Nehdi

Canadian Society for Civil Engineering

The effect of exposing grouted precast wall connections to subfreezing curing temperatures at early-age was explored in this study. In cold weather construction, heating of the surrounding environment of grouted precast wall connections is usually conducted for short periods of time. Hence, subfreezing conditions can affect the strength of the grout and the bond strength of the connection, which can ultimately compromise the integrity of the structure. In this study, grout specimens typical of that used in precast wall construction were cured at ambient conditions for one day, and then placed in an environmental chamber at subfreezing temperatures (-10°C and …

Mat-721: Alkali-Silica Reactivity In Southwestern Ontario Aggregates, Ahmed R. Suleiman, Aaron Jobst, Moncef L. Nehdi

Canadian Society for Civil Engineering

Alkali-silica reaction (ASR) occurs between alkalis in concrete and reactive silica in aggregates. This reaction results in the formation of alkali-silica gel, which fills the pore space in the cementitious matrix, leading to expansion and damage. Reactive aggregates that can cause this type of damage were identified in different locations in Southwestern Ontario. X-Ray diffraction and petrographic analysis were used to investigate the type of reactive minerals in such aggregates. In addition, the effect of using different types of cement replacement-materials, including crushed limestone powder, fly ash, silica fume, and nano-silica on ASR were investigated in cement mortars incorporating the …

Mat-722: Effect Of Fiber Orientation On The Behavior Of Cfrp Confined Concrete Cylinders, Ahmed Sulaiman, Husham Almansour, Hassan Aoude

Canadian Society for Civil Engineering

This paper presents the results of an ongoing experimental investigation examining the effect of fiber orientation and stacking sequence on the behavior of FRP-confined concrete. As part of the experimental study, 100 mm x 200 mm concrete cylinders were jacketed with carbon fiber reinforced polymer (CFRP) sheets and tested under pure axial compressive loading. The specimens were confined using various CFRP stacking sequences, with fibers oriented at 0⁰, 90⁰, and ±45⁰. Furthermore, within each stacking sequence, the numbers of layers was varied from 4 to 8 to examine the effect of number of plies on the behavior of the FRP-confined …

Mat-723: Bond Behaviour Of Grouted Connections Under Monotonic Tensile Loads, Mohamed Elsayed, Douglas James Provost-Smith, Moncef L. Nehdi, Osama Eissa

Canadian Society for Civil Engineering

Grouted bar-in-conduit connections are versatile connections widely used in the precast concrete construction. In precast load bearing wall structures, two vertical wall panels are connected by a reinforcing bar, which is projected from one panel and grouted into a sleeve placed in the other. The main function of the ties is to resist tension induced by in-plane and out-of-plane straining actions and to provide ductility to the wall assembly through the yielding of the reinforcement. Limited information is currently available on the behaviour of such connections. This paper presents the findings of an investigation conducted to investigate the behaviour of …

Mat-724: Low Energy Concrete, Al-Shimaa Abudllatif, Aya-Tallah Elkharbotly, Basma El-Bassiouny, Mennatallah El-Bassiouny, Yousef Amin, Amr Fathy, Mohamed N. Abou-Zeid, Ezzat H. Fahmy

Canadian Society for Civil Engineering

The escalating demand on energy consumption as well as the scarcity of non renewable energy resources represents a major concern worldwide. Hence, efforts are being exerted to resort to lower energy alternatives in almost all aspects of life. Portland cement concrete has been known as an energy intensive material that emits large amount of CO2 during its various stages of manufacturing. While concrete has been classified over the decades based on its performance, it has seldom been assessed and evaluated based on its embodied energy.

This work aims at evaluating concrete mixtures based on energy and CO2 emission together with …

Mat-725: Self Leveling Mortar: Why And How?, Ahmed Hassanein, Eman Shalaby, Omar Amer, Reem Ahmed, Sherif Orban, Amr Fathi, Yousef Abu Gharieb, Mohamed N. Abouzeid, Ezzat H. Fahmy

Canadian Society for Civil Engineering

Concrete floors can develop faults over time which can cause damage thus hindering smooth transportation, industrial aspects and some residential drawbacks. In addition, flaws and cracks are known to progress into more serious damage with time and use. Self leveling mortar has been used on a relatively limited scale worldwide to allow for more even, higher performance and easy-to-apply flooring. However, there has been little information available with respect to their use and best practices.

The primary focus of this work is to prepare mortar that possesses self-levelling flow characteristics. Hence, several mixtures have been designed using various constituents with …

Mat-731: Mechanical & Durability Properties Of Engineered Cementitious Composites With Different Aggregates, Mohamed A. A. Sherir, Khandaker M. Anwar Hossain, Mohamed Lachemi

Canadian Society for Civil Engineering

This paper presents the outcome of a study conducted to exhibit the effect of micro-silica sand and mortar sand on fresh, mechanical and durability properties of Engineered Cementitious Composites (ECCs). ECC is a ductile concrete characterized by strain hardening and multiple-cracking behavior under tension and shear. This study used locally available aggregates instead of standard micro-silica sand to produce cost-effective, sustainable and green ECC mixtures to be used for construction applications. ECCs prepared by both types of sands exhibited almost similar behaviour in terms of fresh, mechanical and durability properties which indicated the viability of producing ECC mixtures with mortar …

Mat-732: Experimental Study On The Capacity Of Barrier Deck Anchorage In Mtq Pl-3 Barrier Reinforced With Hm-Gfrp Bars With Headed Ends, Michael Rostami, Khaled Sennah, S. Milad Dehnadi

Canadian Society for Civil Engineering

A recent design work conducted at Ryerson University on PL-3 bridge barrier has led to an economical glass fibre reinforced polymer (GFRP) bar detailing for sustainable construction. A PL-3 barrier wall of 27.6 m length was constructed using the proposed GFRP bar configuration, incorporating the use of V-Rod headed-end bars. The proposed barrier configuration was recently crash tested to qualify its use in Canada’s highway bridges. Then, wall segments of this barrier were tested under static loading to-collapse to determine their structural behavior, crack pattern and ultimate load carrying capacity under simulated vehicle impact load. Test results led to establishing …

Mat-734: Increasing The Durability And Resilience Of Tall Buildings With Precast Concrete Enclosure Systems, Randy A. Van Straaten, John F. Straube, C. Alex Lukachko

Canadian Society for Civil Engineering

In this paper precast concrete wall systems are compared to curtain wall and window wall systems in terms of durability and disaster resilience of multi-story buildings. Window wall systems are currently the enclosure system of choice for tall residential buildings in most parts of North America.

Precast concrete wall systems can be expected to last the lifetime of a building with routine seal replacement. These are highly durable systems. Windows within precast concrete wall systems will require replacement in 25-35 years but represent a limited portion of the wall area and hence are less costly and have less impact on …

Mat-735: Optimizing Performance Of Zinc Coated Reinforcing Steel In Concrete Structures, Martin Gagné, Shannon Pole, Frank Goodwin, Gary Dallin

Canadian Society for Civil Engineering

Corrosion of steel reinforcing bar (rebar) is the most significant cause of concrete failure, resulting in expensive repairs and premature structure replacements across the country. This paper will discuss a new, low-cost, zinc coating process for rebar. The properties of this new coated rebar and its contribution to improvement of concrete performance will be presented together with the status of related national and international standards. The Continuous Galvanized Rebar (CGR) coating process is similar to galvanizing of sheet steel. The zinc coating is durable and resistant to abrasion that is routine during transport and construction, but is also highly ductile …

Mat-736: Development Of High Strength Nano-Silica Modified Rubbercrete, Bashar S. Mohammed, Muhd Fadhil Nuruddin, Nasir Shafiq

Canadian Society for Civil Engineering

Several research works have been carried out to study properties of concrete containing crumb rubber (rubbercrete) as a partial replacement to fine aggregate. Rubbercrete exhibits numerous benefits compared to conventional concrete such as lower in density, increased ductility, enhanced plastic capacity, higher toughness, higher impact resistance, better chloride penetration, lower thermal conductivity, higher noise reduction factor and better electrical resistivity. It has also been known to have better energy dissipation, durability and damping ratio. However, the main drawbacks of rubbercrete are decreasing in strengths and Young's modulus. Therefore, to improve strengths of the rubbercrete, the crumb rubber has been pre-coated …