Elliptical hollow sections (EHS) are the newest steel shape to emerge in the industry, but appropriate design guidance is lacking, being completely absent from Canadian codes and guidelines. Geometric property and compressive resistance tables were established to be potentially added to the Canadian guides. The equivalent RHS method, originally proposed by Zhao and Packer in 2009, was simplified and modified to validate its use for the design of EHS columns and beams. An experimental programme was developed to investigate the behaviour of EHS-to-EHS welded connections. Twelve T and X connection tests were performed to study the effect of connection angle, orientation type and loading. Two methods were developed to predict connection capacities and failure modes: the equivalent CHS and the equivalent RHS approaches. Both methods proved to be conservative on average, but the equivalent RHS approach proved to be more successful at capturing the actual failure mode of EHS-to-EHS connections.

Substructure hybrid simulation has been actively investigated in recent years. The simulation method allows for the assessment of seismic performance of structures by representing critical components with physical specimens and the rest of the structure with numerical models. In this study the system level performance of a six-storey structure with self-centering energy dissipative (SCED) braces was validated through pseudo dynamic (PsD) hybrid simulation. Fragility curves are derived for the SCED system. The study presents the configuration of the hybrid simulation and discusses some of the practical intricacies in performing PsD hybrid simulations. In addition the study addresses some of the challenges associated with the substructuring process during a hybrid simulation. Two techniques, extensive analytical study and model updation, are discussed to improve the response from the hybrid simulation accounting for the variation in global response of a structural system depending on which structural element was represented as a physical specimen.

Freight transport is the output of an economic market, which converts commodity flows into vehicle flows. Interactions in this market influence vehicle flows and since freight market characteristics (product differentiation and economies of scale/scope) violate perfect competition conditions, the output of this market cannot be predicted directly, unless these interactions are represented in the forecasting models. Traditional freight modelling frameworks do not consider these interactions and consequently they may provide inaccurate freight flow forecasts. In this dissertation, a freight modelling framework is proposed using simulation of freight agent interactions in the economic market to forecast freight flows. The framework is named FREMIS (FREight Market Interactions Simulation). The FREMIS framework consists of two demand models to represent shipper decisions (bundling of shipments and carrier selection) in the market and functions based on profit maximizing behaviour to simulate carrier proposals for contracts. Besides that, learning models are proposed to simulate agent learning processes based on their interactions. The framework was developed aiming to create a realistic representation of freight markets using feasible data collection methods. To illustrate the feasibility of the data collection, a customized web survey was implemented with shippers and carriers in a freight market. Two probabilistic models were developed using the data. The first model, a shipment bundling model was proposed combining a probabilistic model and a vehicle routing algorithm. The results of the probabilistic model are presented in this dissertation, where the locations of shipments (origin and destination) influence the probability of bundling them. Second, three carrier selection models were developed aiming to analyse the nonresponse bias and non-attendance problem in the survey. All of these models assumed heteroskedasticity (different scale or variance) in shipper behaviour. In all models, the hypothesis of agents’ heteroskedasticity cannot be rejected. Besides that, nonresponse bias and non-attendance problem were identified in the survey. In conclusion, the models obtained from the survey were consistent with their behavioural assumptions and therefore they can be adopted during FREMIS implementation.

The Integrated Land Use, Transportation, Environment (ILUTE) modelling system simulates the activities of agents within the Greater Toronto and Hamilton Area (GTHA) as they evolve over time. However, in its currently implemented form, ILUTE lacks an endogenous treatment of the labour market and the associated wages. This is seen as the major weakness of the current model. This work describes a labour market framework to partially fill this gap and then develops the dynamic disaggregate model of year to year transitions of the labour force status of the people within the GTHA and the set of wage models components of this framework. The data used is a sample of individuals from the Toronto, Oshawa, and Hamilton Census Metropolitan Areas surveyed over twelve consecutive years between 1995 and 2007 in the Survey of Labour and Income Dynamics.

The Integrated Land Use, Transportation, Environment (ILUTE) modelling system simulates the activities of agents within the Greater Toronto and Hamilton Area (GTHA) as they evolve over time. However, in its currently implemented form, ILUTE lacks an endogenous treatment of the labour market and the associated wages. This is seen as the major weakness of the current model. This work describes a labour market framework to partially fill this gap and then develops the dynamic disaggregate model of year to year transitions of the labour force status of the people within the GTHA and the set of wage models components of this framework. The data used is a sample of individuals from the Toronto, Oshawa, and Hamilton Census Metropolitan Areas surveyed over twelve consecutive years between 1995 and 2007 in the Survey of Labour and Income Dynamics.

The thesis numerically explores the use and behavior of Active Hydraulic Devices (AHDs), creating a new capability to simulate and control a pipe system’s transient performance. Automatic control valves are the first type of AHDs studied in this research. Due to the challenges inherent in the design of a pressure relief valve (PRV), the general principles of PRV use and selection are studied along with the system’s response to the PRV parameters. A new application of PID (proportional, integral and derivative) control valve is envisioned that combines a remote sensor at the upstream end of a pipeline to create a non- or semi- reflective boundary at the downstream end. Case studies show that, with such a boundary, the reflection and resonance of pressure waves within the pipeline are sometimes eliminated and invariably limited. The second type of AHDs studied in this research is the governed hydro turbine, the most complicated hydraulic component in terms of transient analysis and waterhammer control. A complete numerical model is developed for the turbine installations in either urban water networks or conventional hydropower generation systems. Using the model, transient simulations for several realistic hydro projects are presented along with various transient control measures.

Master of Science / Department of Civil Engineering / Mustaque Hossain / The AASHTO Guide for Design of Pavement Structures is the primary document used by the state highway agencies to design new and rehabilitated highway pavements. Currently the Kansas Department of Transportation (KDOT) uses the 1993 edition of the AASHTO pavement design guide, based on empirical performance equations, for the design of Jointed Plain Concrete Pavements (JPCP). However, the newly released Mechanistic-Empirical Pavement Design Guide (MEPDG) provides methodologies for mechanistic-empirical pavement design while accounting for local materials, environmental conditions, and actual highway traffic load distribution by means of axle load spectra. The major objective of this study was to predict pavement distresses from the MEPDG design analysis for selected in-service JPCP projects in Kansas. Five roadway sections designed by KDOT and three long term pavement performance (LTPP) sections in Kansas were analyzed. Project-specific construction, materials, climatic, and traffic data were also generated in the study. Typical examples of axle load spectra calculations from the existing Weigh-in-Motion (WIM) data were provided. Vehicle class and hourly truck traffic distributions were also derived from Automatic Vehicle Classification (AVC) data provided by KDOT. The predicted output variables, IRI, percent slabs cracked, and faulting values, were compared with those obtained during annual pavement management system (PMS) condition survey done by KDOT. A sensitivity analysis was also performed to determine the sensitivity of the output variables due to variations in the key input parameters used in the design process. Finally, the interaction of selected significant factors through statistical analysis was identified to find the effect on current KDOT specifications for rigid pavement construction. The results showed that IRI was the most sensitive output. For most projects in this study, the predicted IRI was similar to the measured values. MEPDG analysis showed minimal or no faulting and was confirmed by visual observation. Only a few projects showed some cracking. It was also observed that the MEPDG outputs were very sensitive to some specific traffic, material, and construction input parameters such as, average daily truck traffic, truck percentages, dowel diameter, tied concrete shoulder, widened lane, slab thickness, coefficient of thermal expansion, compressive strength, base type, etc. Statistical analysis results showed that the current KDOT Percent Within Limits (PWL) specifications for concrete pavement construction are more sensitive to the concrete strength than to the slab thickness. Concrete slab thickness, strength, and truck traffic significantly influence the distresses predicted by MEPDG in most cases. The interactions among these factors are also almost always evident.

Master of Science / Department of Civil Engineering / Asadollah Esmaeily / The accuracy and applicability of the existing stress-strain models for concrete confined by Carbon Fiber Reinforced Polymer (CFRP) were analytically and experimentally explored. This investigation includes major parameters affecting the stress-strain response of confined concrete, including the loading pattern and protocol. It has been observed and reported that the experimentally recorded stress-strain relationship of the same specimen will be different if the loading protocol of the test is switched from displacement control to load control. In the experimental phase of this study, four standard 6" by 12" concrete cylinders were constructed using the same concrete batch for consistency. Three two-inch strain gauges were affixed equally spaced at mid-height on the surface of the specimen in the longitudinal direction, and two two-inch strain gauges were applied in the lateral direction at mid-height opposite each other. CFRP was then impregnated with a two-part epoxy and applied externally in two continuous layers, with an overlap. During the first phase of the experimental program, the tests were conducted with a constant load rate or with a constant displacement rate. The data was collected from externally mounted strain gauges and potentiometers positioned on the opposite sides of the cylinder in the longitudinal direction. Since the capacity of the existing actuator in the structural lab was less than the required failure level of the specimens, a nutcracker-like device was constructed to increase the mechanical advantage of the test frame in the second phase of the experimental program. In this phase, all tests were conducted in displacement control. Various models were selected to be studied from a large number of existing models that propose to determine the stress-strain relationship of concrete. Analytical predictions of the models were compared against the experimental data. Results show that some of the models provide a reasonable prediction of the real performance of the specimen. However, in general, predictions are different from the real performance for most models.

Master of Science / Department of Civil Engineering / Sunanda Dissanayake / Motorists generally follow the guidance provided by the pavement markings while traveling on roads. Under certain circumstances, construction joints may be necessary in concrete pavements, which are generally designed to be coincident with the pavement markings. At some locations, however, the construction joints may not exactly match the pavement markings. These situations may create confusion in the minds of drivers, which may lead them to follow joints instead of the markings. In the absence of detailed studies on this topic, an effort was made in the present study to evaluate the effects of unmatched longitudinal construction joints and pavement markings on the lateral position of vehicles. Sites having the characteristics of unmatched longitudinal construction joints and pavement markings were identified, and detailed data were collected at one of the sites. Video camera technique was used for capturing the movements of vehicles along the test site for longer durations. The video tapes were later reduced in the laboratory to extract necessary information. The distance to the right side of the vehicles from right curb of the road, the type of vehicle, presence of vehicles in the adjacent lane, weather and light conditions, and the movement of the vehicles immediately after traversing the section of the road having unmatched longitudinal construction joints and pavement markings were the main parameters observed while reducing the data. Two surveys were also conducted for gathering the opinions of some practitioners and engineers on the issue. Statistical analyses were carried out using t-tests to evaluate if there were differences. Several comparisons were made for different types of vehicles based on various conditions. The analysis results indicated that there was a statistically significant difference between the actual and expected distances to the center-line of vehicles, implying that the lateral position of vehicles may have been affected by the joints. A model was also developed to determine the lateral position of the vehicles by considering the parameters used in the analysis. Based on the survey results and analysis of field data, it was found that the lateral position of vehicles may have been affected by the unmatched joints and pavement markings.

Master of Science / Department of Architectural Engineering and Construction Science / Darren D. Reynolds / Highly expansive soils can severely damage the foundations which they support. These damages create unnecessary maintenance cost to the owner and can be detrimental to the building superstructure. Post-tensioned ribbed mat foundations are commonly used in light commercial construction in areas in the United States that have highly expansive soils. Mild reinforced ribbed mat foundations are rarely used in these areas. This report investigates why post-tensioned ribbed mat foundations are more common in these areas than mild-reinforced ribbed mat foundations. The approach to this investigation is a design example which designs and compares the two foundation types. The design example is a typical 2-story office building located in Dallas, Texas, which is an area that has highly expansive soils. First, a post-tensioned ribbed mat foundation is designed for the office building. Next, a mild-reinforced ribbed mat foundation is designed for the same building. A comparison is done between the two foundations based on serviceability, strength requirements and construction costs. The findings in the comparison is that post-tensioning is a more economical and constructible method. Using mild-reinforcement requires the use of shear reinforcement in the ribs which is not typical in foundation design and construction and is less economical, and additional reinforcement in the slab is needed to resist bending stresses which is also less economical. The finding of the report is that of the two foundation types, the post-tensioned ribbed mat foundation is the better design based on the three areas of interest listed above. The use of a mild-reinforced mat foundation would require construction procedures that are not typical and would be less economical.