Civil and Environmental Engineering Commons^™

Env-640: Treatment Of Combined Sewer Overflow Using A Natural Coagulant, Omotola Ajao, Rajesh Seth, Paul Drca, Chris Manzon, Nihar Biswas

Canadian Society for Civil Engineering

The hazards posed by combined sewer overflows (CSOs) to receiving water bodies cannot be overemphasised. CSOs can be a significant contributor of pollutants to receiving waterbodies. Ontario’s F-5-5 procedure stipulates a treatment target of a minimum 50% reduction in suspended solids (SS) and 30% reduction in 5-day biochemical oxygen demand (BOD5) for CSOs in the province. The physicochemical coagulation process is an effective and widely used treatment process to achieve these targets. The City of Windsor, Ontario currently uses a synthetic organic coagulant for coagulation at its retention treatment basin (RTB) for CSO treatment. However, environmental persistence and potential toxic …

Env-641: New Methods For Design And Performance Monitoring Of Sub-Slab Venting Systems For Vocs And Radon, Darius Mali, Paul Nicholson, William Wertz, Todd Mcalary

Canadian Society for Civil Engineering

This paper summarizes recent research funded by the U.S. Department of Defense Environmental Security Technology Certification Program (ESTCP) intended to improve the cost-effectiveness of systems to protect building occupants from subsurface radon gas and volatile organic compound (VOC) vapors. Standard practice for sub-slab depressurization (SSD) uses a fan or blower to create a measurable vacuum below the building and has not changed in a few decades. ASTM E-2121-13 specifies a minimum target vacuum of 6 to 9 Pascals (Pa) everywhere below the building floor slab, but this can be difficult to measure compared to baseline fluctuations (a signal-to-noise challenge). A …

Env-643: Sub-Slab Depressurization System Retrofits To Existing Buildings: Two Case Studies, Theresa M. Phillips, Ronald Taylor, Darko Strajin

Canadian Society for Civil Engineering

Ontario Regulation 153/04 outlines the process wherein a property impacted by soil and/ or ground water contaminants is evaluated for risks to human and ecological health, and may be redeveloped for more sensitive land uses. Under the Regulation, once a property has been sufficiently characterized, a Record of Site Condition (RSC) may be filed, to document the condition of the property. Owners of contaminated lands may choose to remediate the property, to meet the Ontario Ministry of Environment and Climate Change (MOECC) generic soil and ground water Standards, or develop new site-specific Standards via the Risk Assessment (RA) process.

Many …

Env-644: Use Of New Models To Support Vapour Intrusion Mitigation Design, Ian Hers, Parisa Jourabchi, Eric Hood, Michael Z'Graggen

Canadian Society for Civil Engineering

Soil vapour intrusion of subsurface volatile organic compounds (VOCs) into indoor air of buildings is a significant potential concern at existing sites where chemical releases occur, or at new buildings at Brownfield sites with residual chemical impacts. While soil vapour intrusion mitigation systems are increasingly being implemented, there are limited published data on mitigation performance for VOCs particularly for industrial or commercial buildings or high density residential buildings with below ground parking garages. Data gaps include the effectiveness of passive and active venting systems and reduction in vapour intrusion that can be achieved relative to unmitigated buildings. Because of lack …

Env-645: Risk Assessment For Asbestos In Soil, Natasha Corrin, Sandra Carrelas

Canadian Society for Civil Engineering

On behalf of the City of Sarnia (the City), Golder Associates Ltd. completed a risk assessment to evaluate potential risks to human health and ecological receptors associated with soil and groundwater contamination at a multi-use recreational municipal park located on the City’s harbour front. Soil and groundwater investigations completed at the site revealed elevated concentrations of a number of typical industrial contaminants (including metals, volatile organic compounds, petroleum hydrocarbons and polynuclear aromatic hydrocarbon) relative to generic regulatory standards. Options for the management/remediation of these impacts were complicated by the observed presence of asbestos in soil at the site and the …

Env-646: Successful Water Reuse – The First Step Toward Zld, Ed Greenwood, Bill Malyk

Canadian Society for Civil Engineering

After years of record-breaking droughts many aquifers around the World are drying up. Climate change is making it increasingly difficult to support the World’s growing population. If water means life then water scarcity represents a significant challenge to growth for industry.

A Canadian-based food processor is rising to the challenge of water scarcity at one of its production facilities in Gujarat, India. Until 2013 the facility was able to draw all the water it needed from a well. However, droughts have reduced groundwater resources and the demand for the facility’s products has grown. The food processor approached Amec Foster Wheeler …

Env-647: Repurposing Existing Infrastructure For Enhanced Wet Weather Flow Treatment For Vauxhall Pcp, City Of London, Louis Tasfi, Geordie Gould

Canadian Society for Civil Engineering

The Vauxhall Pollution Control Plant (PCP) is one of the first Ontario municipal wastewater treatment plants to have implemented a wet weather strategy that involves chemically enhanced primary treatment (CEPT) and chemically enhanced secondary clarification processes and repurposes existing infrastructure.

Wet weather events were a major concern for the City of London (City). Prior to plant upgrade, when major wet weather flows occurred plant overflow would discharge directly into the Thames River. The solution designed by Dillon Consulting Limited treats wet weather flows of nearly ten times the rated average day plant capacity. The average and peak flow treatment capacity …

Env-648: Design Optimization For Enhanced Pollutant Removal Efficiency Of Bioretention Cells, Soheil Gholamreza-Kashi, Thomas Tiveron, Darko Joksimovic

Canadian Society for Civil Engineering

Consulting engineers, conservation authorities, and municipalities are looking for methods of stormwater management control that not only restore pre-development hydrological cycles, but also offer the benefit of runoff quality treatment. As a result, Low Impact Development (LID) approaches, which are often applied at the source, have been gaining in popularity. The objective of this research is to develop guidance for the design of bioretention cells for runoff water quality treatment, evaluating bioretention cells’ ability to perform such treatment function through modelling. A number of different modelling tools have been developed to simulate the performance of bioretention cells. These models are …

Env-650: Two Case Studies: Delivery Of Decentralized Wastewater Solutions In Ontario And India, Gillian C. Dumencu, Yuxin Wang, Wilf G. Stefan

Canadian Society for Civil Engineering

This paper presents two case studies for the delivery of wastewater servicing solutions: one in Ontario, Canada and the other in Gujarat State, India. In each case a decentralized small diameter gravity sewer wastewater collection and treatment system was implemented for servicing residential development—with some interesting differences and similarities. The first case is a small private mobile home park in Eastern Ontario under a Ministry of Environment Order to address failing on-site septic systems. The Municipality was obliged to take over operation of the on-site systems; however, there were not adequate funds available to rectify the failing systems. A group …

Env-651: Highly Effective Electro-Fenton Oxidation Treatment For Concentrated Brewery Wastewater, Sharmin Sultana, Md. Saifur Rahaman, Alexander Baltodano

Canadian Society for Civil Engineering

The brewing industry typically produces 3-10 liters of wastewater per liter of beer produced which contains sugars, soluble starch, ethanol, and volatile fatty acids (VFAs) and is typically characterized by 2,000-20,000 mg/L COD, 200-3,000 mg/L total suspended solids (TSS), and 10-124 mg/L phosphorus. In this study, the high strength brewery wastewater was treated with a multi-plated (BDD/Graphite) electrolysis cell configuration with Fenton’s reagent in a galvanostatic mode of operation. A novel cell configuration with five electrode plates (BDD/Graphite), which provide a higher current/voltage ratio than the conventional three plate configuration, was used in this study to provide more surface for …

Env-652: Conventional Vs Low Impact Development Stormwater Management Case Studies, Imtiaz Shah, Ron Antuma

Canadian Society for Civil Engineering

Low Impact Development (LID) Stormwater Management (SWM) techniques is the appropriate approach to be applied to site developments in an attempt to mimic a site’s natural hydrologic cycle to store and treat stormwater runoff close to where it falls. In 2014, the UTRCA conducted a survey of member municipalities to gauge a familiarity with SWM LIDs to help UTRCA effectively target their efforts regarding SWM LID during a development and planning process at the Municipal level. Several issues were highlighted from the survey results, including the presence of institutional, technical, and physical barriers, as well as a general lack of …

Env-653: Production Of Biosurfactant By Rhodococcus Erythropolis Sp. Cultivated In A Novel Fish Waste Compost Extract Substrate, Khoshrooz Kazemi, Baiyu Zhang, Leonard M. Lye

Canadian Society for Civil Engineering

Compost generated through fish waste composting could provide an effective source of nutrient-rich organic matter for microbial growth, leading to the production of valuable products such as biosurfactants. Existing biosurfactant production is a relative expensive process and raw materials contribute about 30% of the production cost. Utilizing waste streams such as fish waste compost (FWC) as a substrate is an economically viable alternative. In this study, biosurfactant was produced by Rhodococcus erythropolis sp. P6-4P, a strain isolated from the North Atlantic Ocean. Biosurfactant production with FWC extract was compared with other soluble and insoluble carbon and nitrogen sources using emulsification …

Env-654: Numerical Modelling Of Smouldering Combustion To Optimize Ex Situ Soil Treatment System Design, Rebecca L. Solinger, Jason I. Gerhard, Gavin P. Grant, Grant C. Scholes

Canadian Society for Civil Engineering

There is widespread soil contamination at thousands of cites in Canada resulting from the historical improper storage and disposal of industrial liquids (Story et al., 2014). Large financial resources are allocated to remediation efforts due to the human and environmental health risks associated with exposure to such contamination, with over $582 million CAN spent on remediation in 2014-15 by the Canadian government alone (Treasury Board of Canada, 2016). Our scientific understanding of site remediation has evolved greatly over the past decades and it is now widely accepted that remediation of the contaminant source zone is necessary to achieve a high …

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-715: Sustainable High-Volume Fly Ash Grouts For Two-Stage Concrete, Manal F. Najjar, Ahmed M. Soliman, Moncef L. Nehdi

Canadian Society for Civil Engineering

Two-stage concrete (TSC) is a special type of concrete in which coarse aggregates are pre-placed in the formwork and subsequently injected with a grout. Beneficiating fly ash in TSC grouts increases TSC sustainability through the ecological use of large quantities of fly ash, reduced carbon-dioxide emissions associated with cement production, and enhancement of resource productivity of the concrete industry. Limited research has explored the effects of using high volume of fly ash as partial replacement for cement in TSC grout mixtures. Therefore, the flowability of grout mixtures incorporating various fly ash addition rates (i.e. 0%, 30%, 50% and 70%) was …

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-717: Mechanical Performance Of Hybrid Fibre-Reinforced Engineered Cementitious Composite Incorporating Nitisma Short Fibres, Mohamed A. E. M. Ali, Moncef L. Nehdi

Canadian Society for Civil Engineering

A new high-strength, high-tensile ductility hybrid fibre-reinforced engineered cementitious composite (HECCSMAF) incorporating randomly dispersed nickel-titanium shape memory alloy short fibres (NiTi-SMA) has been pioneered in this study. The mechanical properties of the HECC-SMAF produced with a combination of 2% polyvinyl-alcohol (PVA) and 0.5%, 1%, and 1.5% NiTi-SMA fibres by volume fraction have been explored. The experimental results indicate that utilizing a combination of those fibres can enhance the tensile capacity of ECC by up to 39% with a slight to no increase in compressive strength. An overall reduction in workability was observed compared to that of ECC made with only …

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-720: Effect Of Pore Structure On Concrete Deterioration By Physical Sulphate Attack, Ahmed R. Suleiman, Moncef L. Nehdi

Canadian Society for Civil Engineering

Repeated crystallisation of salt minerals has been considered as the driving force for surface scaling of concrete exposed to physical sulphate attack. This damage is initiated when stresses induced by the internal pressure created via repeated salt crystallisation exceed the tensile strength of the concrete. The degree of such damage will depend mainly on the structure and connectivity of pores, which control the penetration of sulphates into the concrete. Several factors affect the pore structure including the concrete constituents, mixture proportions and the curing process. Therefore, in this paper, the effect of the pore structure on concrete deterioration by physical …

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 …