Showing papers in "Canadian Journal of Civil Engineering in 2001"
TL;DR: The use of conventional water and wastewater treatment processes becomes increasingly challenged with the identification of more and more contaminants, rapid growth of population and industrial act... as mentioned in this paper, and the increasing number of contaminants.
Abstract: The use of conventional water and wastewater treatment processes becomes increasingly challenged with the identification of more and more contaminants, rapid growth of population and industrial act...
449 citations
150 citations
TL;DR: In this article, the basic concepts of tension stiffening behaviour of reinforced concrete members under tension are reviewed, and different approaches to account for this behaviour are linked together, including a...
Abstract: Basic concepts of tension stiffening behaviour of reinforced concrete members under tension are reviewed, and different approaches to account for this behaviour are linked together. This includes a...
137 citations
TL;DR: In this article, composite beams with corrugated steel webs represent a new innovative system which has emerged in the past decade for short and medium span bridges, usually combining the usage of cor...
Abstract: Composite beams with corrugated steel webs represent a new innovative system which has emerged in the past decade for short and medium span bridges. The new system usually combines the usage of cor...
135 citations
TL;DR: In this article, the authors reviewed the 1975 Turkish code provisions to provide the background for design and detailing of structures prior to the earthquake and the performance of reinforced concrete and masonry structures.
Abstract: The 1975 Turkish code provisions are first reviewed to provide the background for design and detailing of structures prior to the earthquake. The performance of reinforced concrete and masonry stru...
121 citations
TL;DR: In this article, the authors reviewed various methods used to activate the pozzolanic activity of natural pozzolans and classified them into three catalogues: thermal, mechanical, and chemical activation.
Abstract: Natural pozzolan is one of the oldest construction materials. Lime-pozzolan cements have been used for several thousands of years and have an excellent reputation for their durability. Pozzolans are being widely used as a cement replacement in Portland cement concrete. The use of pozzolans has the advantage of lower costs and better durability, but the disadvantage of a longer setting time and a slower early strength development. Different techniques have been tried to increase the reactivity of natural pozzolans to overcome these disadvantages. This paper has reviewed various methods used to activate the pozzolanic activity of natural pozzolans. All activation methods can be classified into three catalogues: thermal, mechanical, and chemical activation. A comparison based on strengthcost relationship indicates that the chemical activation method is the most effective and cheapest one.Key words: activation, reactivity, natural pozzolans, pozzolanic reaction, calcination, elevated temperature curing, chem...
85 citations
TL;DR: The full economic impact of man-induced land subsidence is large as discussed by the authors, and it is caused by human activities in many countries all over the world, including China and India.
Abstract: Land subsidence, lowering of the land surface by mass movement, has been caused by human activities in many countries all over the world. The full economic impact of man-induced subsidence is large...
70 citations
TL;DR: In this paper, the design engineer is concerned first with the ultimate disposal and utilization of the biosolids, providing at least two options for the final disposal: volume reduction, stabilization or vector attraction reduction, and pathogen inactivation.
Abstract: Treated as a valuable resource, municipal sludge, often today referred to as biosolids, is processed through a variety of novel unit operations leading to a safe, aesthetically pleasing, and sought-after product. The design engineer is concerned first with the ultimate disposal and utilization of the biosolids, providing at least two options for the final disposal. Volume reduction, stabilization or vector attraction reduction, and pathogen inactivation are the key goals; process trains combining them into one unit process are the target technologies. Drying and pelletization are now being applied at much smaller plants because of the introduction of indirect dryers, which have fewer air pollution problems than the direct dryers still used at some larger plants. Stabilization of biosolids in newer plants is more often combined with disinfection at thermophillic temperatures, in anaerobic and particularly in aerobic regimes. For the smallest plants, dewatering is now available in drying bags or vacuum dryi...
67 citations
TL;DR: In this paper, the hysteretic behavior of buckling inhibited braces (BIBs) made of low yield strength steel is investigated experimentally, and the results from four large-scale specimens showed that the BIB is able to prevent early buckling and cracking that occur in conventional braces and develop to the full capacity the strength, ductility, and energy-dissipation capacity of the steel used.
Abstract: The hysteretic behavior of buckling inhibited braces (BIBs) (or unbonded braces) made of low yield strength steel is investigated experimentally. Test results from four large-scale specimens showed that the BIB is able to prevent early buckling and cracking that occur in conventional braces and develop to the full capacity the strength, ductility, and energy-dissipation capacity of the steel used. In addition, the use of low yield strength steel results in small yield deformation and dramatic strain hardening of the BIB. Earthquake simulation tests of a 0.4-scale three-storey ductile concentrically braced frame (DCBF), which employed low yield strength steel BIBs as concentric braces, were carried out. Test results verified the applicability of the BIB and the high seismic performance of the DCBF. The idea of controlled plastification worked well. In addition, both the 70% lateral-force distribution requirement of the Uniform Building Code and the 30% lateral-force distribution requirement of CAN/CSA-S16....
65 citations
TL;DR: In this article, the authors use artificial intelligence to improve drinking water quality while reducing operating costs, and many drinking water utilities are investing in advanced process control and automation technologies The use of artificial intellig
Abstract: To improve drinking water quality while reducing operating costs, many drinking water utilities are investing in advanced process control and automation technologies The use of artificial intellig
64 citations
TL;DR: In this paper, the seismic behavior of chevron steel braced frames for 2-, 4-, 8-, and 12-storey steel building structures is described. And two different design approaches were considered: one that correspo...
Abstract: This paper describes the seismic behaviour of chevron steel braced frames for 2-, 4-, 8-, and 12-storey steel building structures. Two different design approaches were considered: one that correspo...
TL;DR: In this paper, the authors describe the design, development, and application of a special purpose simulation tool for actual tunnel construction operations performed by the City of Edmonton Public Works Department and describe the decision-making process adopted by the model developers and the construction industry personnel during the design and implementation of the simulation.
Abstract: Simulation is a powerful tool for decision making. It provides an appealing approach to analyze and improve repetitive processes such as tunnelling. Notwithstanding this appeal, application of simulation to real-life construction projects has been minimal. This paper describes the design, development, and application of a special purpose simulation tool for actual tunnel construction operations performed by the City of Edmonton Public Works Department. The implementation of this tool in industry was successful and serves as a model for others to follow. The decision-making process adopted by the model developers and the construction industry personnel during the design, development, and implementation of the simulation are described. The cost-planning tool in the tunnel template is very useful in making decisions and evaluating the feasibility of tunnel construction projects. The real-life application of various alternatives compared to the conceptual estimates prepared for a proposed tunnel project to be...
TL;DR: In this article, the effect of grain size on the dynamics of local scour processes is discussed in the context of the erosion that takes place downstream from a submerged sluice gate.
Abstract: In this study, the effect of grain size on the dynamics of local scour processes is discussed in the context of the erosion that takes place downstream from a submerged sluice gate. Four gradations...
TL;DR: In this paper, an expert system called Intelligent Flood Management System for the selection of appropriate flood damage reduction measures for a given area is described, which is based on hydraulic, hydrological, geotechnical, environmental and economic factors related to the river system and the area to be protected from floods.
Abstract: Heuristic knowledge has been integrated with analytical tools to support decision making for flood management. Development of an expert system called Intelligent Flood Management System for the selection of appropriate flood damage reduction measures for a given area is described. The selection of flood damage reduction measures is based on hydraulic, hydrological, geotechnical, environmental, and economic factors related to the river system and the area to be protected from floods. The knowledge base of the Intelligent Flood Management System is generic and can be used to identify a suitable flood management option for any area. The model base of the Intelligent Flood Management System consists of the hydraulic analysis package HEC-RAS, the flood damage analysis program HEC-FDA, and a model for economic analysis. The graphical user interface is developed for effective communication with the system. The developed system has been implemented to identify appropriate flood damage reduction options for the to...
TL;DR: In this article, the authors highlight the problem of a purely hydrologic approach for design flood estimates using several case studies, and suggest procedures to routinely include geomorphic processes in standard flood frequency studies.
Abstract: Estimates of design flood frequencies are routinely required for engineering purposes on ungauged streams and streams with a limited period of streamflow record. In these cases, the design flood is determined either by rainfall frequencyduration analysis, regional analysis of streamflow data, or by extrapolation of a short record from a gauged stream. Although these types of analyses are valuable in a first approximation of peak discharges for different return periods, there is increasing evidence that geomorphic processes such as debris flows, landslide dam failures, glacial outburst floods, and even snow avalanches in the watershed can significantly exceed these estimates. This paper highlights the problem of a purely hydrologic approach for design flood estimates using several case studies, and suggests procedures to routinely include geomorphic processes in standard flood frequency studies.Key words: debris flows, debris floods, landslide dams, flood hazards, outburst floods, frequency analysis.
TL;DR: In this paper, field and laboratory studies were used to study the influence of temperature and O2 on the bioremediation of diesel-fuel contaminated soil, which was obtained from a landfarm located in North...
Abstract: Field and laboratory studies were used to study the influence of temperature and O2 on the bioremediation of diesel-fuel contaminated soil. Field data were obtained from a landfarm located in North...
TL;DR: In this article, a set of empirical equations has been developed which defines the peak efficiency and shape of the efficiency curve for hydraulic turbines as a function of the commissioning date for the unit, rate and power.
Abstract: A set of empirical equations has been developed which defines the peak efficiency and shape of the efficiency curve for hydraulic turbines as a function of the commissioning date for the unit, rate...
TL;DR: In this paper, the prediction of hydrodynamic damping due to baffles in a fluid-filled rectangular tank or reservoir undergoing horizontal oscillations is described, which involves an assessment of the total energy in the fluid associated with sloshing motions and the average rate of energy dissipation due to flow separation around the baffles.
Abstract: The present paper describes the prediction of hydrodynamic damping due to baffles in a fluid-filled rectangular tank or reservoir undergoing horizontal oscillations. The estimation of hydrodynamic damping involves an assessment of the total energy in the fluid associated with sloshing motions and the average rate of energy dissipation due to flow separation around the baffles. Experimental measurements of hydrodynamic damping have been carried out to validate the theoretical model and to investigate the effectiveness of various baffle configurations. Recommendations are made regarding the assessment of hydrodynamic damping in earthquake engineering applications.Key words: baffles, hydrodynamic damping, sloshing, tanks.
TL;DR: The fuzzy expert system provides accurate linguistic predictions of design performance parameters and is useful and realistic in modeling design performance and in capturing the inherent subjectivity involved.
Abstract: This paper describes a fuzzy expert system for design project performance evaluation and prediction. It presents a comprehensive framework of factors that impact design performance and factors used...
TL;DR: In this paper, the authors proposed a method for source separation of municipal solid waste into wet and dry streams, which is proving to be an attractive alternative in dealing with solid waste, and in achieving provincial and national waste diversion.
Abstract: Source separation of municipal solid waste into wet and dry streams is proving to be an attractive alternative in dealing with solid waste, and in achieving provincial and national waste diversion ...
TL;DR: The continuing trend towards the design of more slender, lighter, and livelier footbridges has created new challenges that are not properly addressed in a number of widely used codes of practice in this article.
Abstract: The continuing trend towards the design of more slender, lighter, and livelier footbridges has created new challenges that are not properly addressed in a number of widely used codes of practice in...
TL;DR: The performance of buildings during the 2001 Kachchh earthquake in the province of Gujarat in India is discussed in this paper, where a majority of the buildings in the earthquake region wer...
Abstract: The performance of buildings during the January 26, 2001, earthquake in the Kachchh region of the province of Gujarat in India is discussed. A majority of the buildings in the earthquake region wer...
TL;DR: In this paper, the main focus of the paper is the framework for analysing ice loads on the Confederation Bridge across the Northumberland Strait, using probabilistic methods, and safety targets were given as a beta factor of 4.0 for a 100-year lifetime, amounting to a probability of failure of about 3 × 10-7 per year.
Abstract: The main focus of the paper is the framework for analysing ice loads on the Confederation Bridge across the Northumberland Strait, using probabilistic methods. Safety targets were given as a beta factor of 4.0 for a 100-year lifetime, amounting to a probability of failure of about 3 × 10-7 per year. The ice regime comprises rafted and ridged ice, and peak loads are expected during March and April of each year. A simulation method was developed, in which loads are calculated corresponding to individual interactions associated with ridges in the ice floes that traverse the strait. The floes are driven by environmental driving forces, and the highest loads occur when these exceed the ridge failure loads. The load results from failure of the consolidated layer and rubble keel. Methods for the analysis of this are described. The determination of extreme loads depends on the number of interactions per year. Difficulties in modelling are described, together with techniques for analysis, such as updating of proba...
TL;DR: In this paper, different shear design methods for reinforced concrete beams strengthened externally with fiber reinforced polymer (FRP) sheets were compared by using the test results from the University of Alberta.
Abstract: This paper reviews the different shear design methods found in the literature for reinforced concrete beams strengthened externally with fibre reinforced polymer (FRP) sheets and compares the adequacy of each method by using the test results from the University of Alberta. The FRP shear design methods presented include the effective FRP strain and the bond mechanism criteria, the strut-and-tie model, the modified compression field theory, and a mechanical model based on the strip method with shear friction approach. Sixteen full-scale T-beam test results were used in the evaluation. Two web heights of 250 and 450 mm and two ready mix concrete batches of 29 and 44 MPa were used in the test specimens. Closed stirrups were used with three spacings: 200 mm, 400 mm, and no stirrups. Three types of FRP were used to strengthen externally the web of the T-beams: (i) uniaxial glass fibre, (ii) triaxial (0/60/60) glass fibre, and (iii) uniaxial carbon fibre. The results showed that the mechanical model using the s...
TL;DR: In this paper, the inelastic response of a typical 12-storey ductile reinforced concrete flexural wall is examined under strong earthquake ground motions to determine the importance of Pdelta effects and assess...
Abstract: The inelastic response of a typical 12-storey ductile reinforced concrete flexural wall is examined under strong earthquake ground motions to determine the importance of Pdelta effects and assess ...
TL;DR: In this article, an experimental study was conducted to investigate the bond behavior between corroding reinforcing steel and surrounding synthetic fiber reinforced concrete, and the results indicated that the use of fibers delayed initiation of cracking, due to steel corrosion, and improved the ultimate bond strength at cracking and post-cracking stages.
Abstract: An experimental study was conducted to investigate the bond behavior between corroding reinforcing steel and surrounding synthetic fiber reinforced concrete. Pullout concrete and fiber reinforced concrete specimens were prepared at concrete cover to steel bar diameter ratios of 3.1 and 3.7 with three embedded lengths of 100, 200, and 300 mm. Fiber reinforced concrete was prepared using polypropylene at 0.15% and 0.30% or nylon fibers at 0.3% by mix volume. After moist curing for 90 days, pullout specimens, originally contaminated by up to 11 kg/m3 NaCl, were subjected to a special treatment to accelerate corrosion in steel. The bond stressslippage relationship was evaluated at different corrosion levels. The findings indicated that the use of fibers delayed initiation of cracking, due to steel corrosion, and improved the ultimate bond strength at cracking and post-cracking stages. The percentage improvement in ultimate bond strength at the latter stages reached as high as 52% and 87%, respectively. It wa...
TL;DR: In this article, a composite reliability model is developed for the reliability assessment of bridge pier scour using static resistance -loading interference, based on the physical interpretation of the phenome-non and a statistical analysis of the available information, the relative maximum scour depth (corresponding to the min-imum required relative pier footing elevation) and the linear combination of the relative approach flow depth and flow Froude number are defined as the system resistance and external loading, respectively.
Abstract: Bridge scour is an extremely complex phenomenon because of the random characteristics of sediment laden flow in close proximity to piers and abutments. This occurrence leads to high uncertainties and unavoidable risk in bridge pier and abutment design. In this study, a composite reliability model is developed for the reliability assessment of bridge pier scour using static resistance - loading interference. Based on the physical interpretation of the phenome - non and a statistical analysis of the available information, the relative maximum scour depth (corresponding to the min - imum required relative pier footing elevation) and the linear combination of the relative approach flow depth and flow Froude number are defined as the system resistance and external loading, respectively. By examining a set of labora- tory and field data, a two-parameter bivariate lognormal distribution is found to represent the joint probability density function of resistance and loading. Reliability expressions are developed in terms of resistance. Use of the model is il - lustrated in a practical application in which a relationship is obtained between the reliability and safety factors under various return periods. This information is of importance in decision making.
TL;DR: In this article, the verification tests carried out at the Royal Military College of Canada on wood, steel, wood and wood-steel bolted connections are described. But, the results of these tests seem to overestimate the strength of the material.
Abstract: This paper covers the verification tests carried out at the Royal Military College of Canada on woodsteelwood and woodsteel bolted connections Thirty groups of specimens were tested Specimen configurations were selected in such a way to include fundamental brittle and ductile failure mode cases Comparisons between experimental results and predictions from proposed equations developed from steelwoodsteel bolted connections are given Proposed design equations were found to provide better predictions of the ultimate loads than current CSA Standard O861 design procedures especially for bearing However, row shear-out predictions seem to overestimate the strength An adjustment using the reduced (effective) thickness concept is therefore proposed Experimental observations on specimens that failed in row shear-out indicated that shear failure occurred over a reduced thickness Stress analysis confirms findings on the reduced thickness The research program is described in this paper along with the re
TL;DR: In this paper, a redefinition of stiffness and yield displacement allows more realistic predictions of the important feature of seismic response, component displacements, and their applications are interwoven with the designer's intentions.
Abstract: It is postulated that for purposes of seismic design, the ductile behaviour of lateral force-resisting wall components, elements, and indeed the entire system can be satisfactorily simulated by bilinear forcedisplacement modeling. This enables displacement relationships between the system and its constituent components at a particular limit state to be readily established. To this end, some widely used fallacies, relevant to the transition from the elastic to the plastic domain of behaviour, are exposed. A redefinition of stiffness and yield displacement allows more realistic predictions of the important feature of seismic response, component displacements, to be made. The concepts are rational, yet very simple. Their applications are interwoven with the designer's intentions. Contrary to current design practice, whereby a specific global displacement ductility capacity is prescribed for a particular structural class, the designer can determine the acceptable displacement demand to be imposed on the syst...
TL;DR: Many jurisdictions throughout Canada and the United States allow the decision to proceed with an active site cleanup, an evaluation or monitoring program, or site closure to be determined from the decision-making process as mentioned in this paper.
Abstract: Many jurisdictions throughout Canada and the United States allow the decision to proceed with an active site cleanup, an evaluation or monitoring program, or site closure to be determined from the ...