Civil and Environmental Engineering Commons^™

Pilot-Scale Test Of Water Wash Carbon Dioxide Absorption System For Purifying Landfill Gas At Jones Island Wastewater Reclamation Facility, Rebecca Schruender

Theses and Dissertations

Biogas, a product of the digestion of organic material, consists primarily of methane and carbon dioxide. By purifying raw biogas, or removing the carbon dioxide, it can be upgraded to biomethane, which can be used to generate heat and electricity or as a substitute for natural gas. An effective method of biogas purification is the water wash process, which consists of an absorption column in which a stream of biogas runs counter-current to a stream of water. The carbon dioxide dissolves in the water, increasing the methane concentration of the gas. A pilot scale system was operated at Jones Island …

Underwater Particle Image Velocimetry (Piv) Measurement Of Turbulence Over Mussel Bed In A Deepsite Of Lake Michigan, Tong Jin

Theses and Dissertations

The influence of the benthic filter feeders, such as bivalves, on ecosystem plankton, and nutrient dynamics is considered significant in shallow marine and freshwater systems. Recent indirect evidence showed that the profundal quagga mussels (Dreissena rostriformis bugensis) have fundamentally altered energy flow and dynamics of nutrients and phytoplankton in Lake Michigan and other Great Lakes. To investigate the phytoplankton grazing rate of the quagga mussel and the mussel siphon currents induced bio-mixing, a self-contained in situ Underwater Particle Image Velocimetry was developed to measure the turbulence structure and the turbulent diffusion coefficient immediately above the profundal quagga mussel covered substrate …

Application Of Survival Analysis Techniques To Probabilistic Assessment Of Fatigue In Steel Bridges, Azam Nabizadehdarabi

Theses and Dissertations

The fatigue of engineering materials under repetitive loading is a significant issue affecting the design and durability of components and systems in a variety of engineering-related applications including civil, mechanical, aerospace, automotive, and electronics. Many factors can affect the service life of a component or system under repetitive loading, such as the type of structure, loading, connection details, stress state, peak stress or stress range, surface condition, temperature, and environmental exposure. Currently, there is no comprehensive probabilistic approach that can systematically address all the factors that contribute to fatigue on a single mathematical platform. However, advanced analysis techniques developed for …

Dynamic Vehicular Trajectory Optimization For Bottleneck Mitigation And Safety Improvement, Wenqing Chen

Theses and Dissertations

Traffic bottleneck is defined as a disruption of traffic flow through a freeway or an arterial, which can be divided as two categories: stationary bottleneck and moving bottleneck. The stationary bottleneck is mainly formed by the lane drops in the multi-lane roadways, while the moving bottleneck are due to the very slowing moving vehicles which disrupt the traffic flow. Traffic bottlenecks not only impact the mobility, but also potentially cause safety issues.

Traditional strategies for eliminating bottlenecks mainly focus on expanding supply including road widening, green interval lengthening and optimization of intersection channelization. In addition, a few macroscopic methods are …

Optimizing Hydrogen Sulfide Removal And Biogas Production Using The Water Wash Method, Brian Leightner

Theses and Dissertations

Biogas forms from decomposing organic material in agricultural digesters, landfills, and wastewater treatment plant digesters. Biogas is mostly composed of methane, and can be used as a carbon-based fuel. Microorganisms that consume organics in these waste streams also produce hydrogen sulfide (H2S) as part of the biogas, in varying trace amounts. H2S is corrosive to engines and pipes for machinery, a human health hazard when inhaled, and an aquatic hazard when dissolved in water. Water washing is an absorption process that dissolves hydrogen sulfide and other water soluble compounds in this process and carries it away from the gas, thereby …

Conditional Survival Analysis For Concrete Bridge Decks, Azam Nabizadeh, Habib Tabatabai, Mohammad A. Tabatabai

Civil and Environmental Engineering Faculty Articles

Bridge decks are a significant factor in the deterioration of bridges, and substantially affect long-term bridge maintenance decisions. In this study, conditional survival (reliability) analysis techniques are applied to bridge decks to evaluate the age at the end of service life using the National Bridge Inventory records. As bridge decks age, the probability of survival and the expected service life would change. The additional knowledge gained from the fact that a bridge deck has already survived a specific number of years alters (increases) the original probability of survival at subsequent years based on the conditional probability theory. The conditional expected …

Prototyping Elliptically Profiled Inverted Pendulum Walls In Cross-Laminated Timber (Clt) For Passive Self-Centering And Seismic Resiliency, Marco Lo Ricco

Theses and Dissertations

Cross-laminated timber (CLT) buildings garnered international attention, nearly a decade ago, for elevating wood construction to new heights on fully panelized assemblies of floors and walls. While highly regarded as a sustainable building material, use of CLT as a structural wall system depends on seismically resilient strategies like controlled rocking. This project prototyped elliptically profiled CLT panels and slotted-pin steel connections, at full-scale, to produce rolling and slip-friction inverted pendulum wall systems of one-story height and inspired by seismic isolation concepts. Digital fabrication realized elliptical profiles along the load-bearing edges of six 5-ply CLT panels and various customized slot shapes …

Energy Dissipating Connector For Precast Shear Walls In High-Seismic Areas, Mohammed Aljuboori

Theses and Dissertations

ABSTRACT

ENERGY DISSIPATING CONNECTOR FOR PRECAST SHEAR WALLS IN HIGH-SEISMIC AREAS

By

Mohammed Aljuboori

The University of Wisconsin – Milwaukee, 2019

Under the Supervision of Dr. Habib Tabatabai

Precast concrete systems are widely used in a variety of structures such as parking garages, residential units, shopping centers, and transportation stations. In some cases, precast structures are preferred over conventional cast-in-place (CIP) concrete conventional structures because of ease of construction, rapid implementation, and lower levels of energy consumption. One area where precast systems have traditionally been at a disadvantage is high seismic applications. In seismic regions, precast concrete structures must have …

Study Of The Long-Term Shaft Resistance Of Energy Piles In Saturated Clays, Saeed Yazdani Kachooie

Theses and Dissertations

This research aims to qualitatively/quantitively assess the effect of temperature variation on the energy pile shaft resistance. The important mechanisms by which heating can change the shear strength of clay and clay-concrete interface are evaluated using experimental and numerical methods. As for experimental method, temperature-controlled triaxial tests, constant normal load (CNL) direct shear tests and small-scale pile tests were conducted. As for numerical approach, a fully coupled thermo-hydro-mechanical (THM) analysis was performed to simulate the experimental test results so that the capability of such analysis to predict thermo-mechanical behavior of energy piles is evaluated. Reconstituted (HC-77) kaolin clay, one-dimensionally consolidated …

Construction Of Bismuth Oxyhallide-Based Heterojunction-Structured Composite And Its Environmental Application For Water Treatment, Li Wang

Theses and Dissertations

With the rapid development of the global economy, environmental protection and sustainable development have become the main trends of current society. In particular, water pollution and energy shortage are outstanding issues that need to be solved in a clean and sustainable way. Recently, semiconductor-based photocatalytic technology, an environmentally friendly technique, has attracted enormous attention and become an emerging research hotspot in the application of water/wastewater treatment and generation of renewable energy as it can convert infinite solar energy into chemical energy. Conventional semiconductor materials usually have a relatively large band gap that only responds to the ultraviolet light, which largely …

Structural Health Monitoring Of Laminate Structures Using Shear-Mode Piezoelectric Sensors, Hussain Altammar

Theses and Dissertations

Structural health monitoring (SHM) employing embedded piezoelectric transducers has shown potential as a promising solution for inspection of different engineering structures such as aircraft, bridges, and renewable energy structures. Despite advancements in the field of ultrasonic SHM, inspection of laminate structures is still a major challenge due to their susceptibility to various joint defects. This thesis presents a novel approach to tackle the challenge of inspecting laminate structures using shear-mode (d35) piezoelectric transducers that are made of lead zirconate titanate (PZT).

This study begins with the characterization of d35 piezoelectric transducers using analytical, numerical, and experimental approaches. The results were …

Analysis Of Frp-Wrapped Concrete Piles In Integral Abutment Bridges Subjected To Axial And Cyclic Lateral Loads, Hassan Mohammed Magbool

Theses and Dissertations

ABSTRACT

The long-term maintenance problems associated with expansion joints, which are used to accommodate bridge movements in conventional bridges, have been the primary motivation for the use of integral abutment (jointless) bridges. These bridges rely on the interaction between the structure and the surrounding soil to accommodate bridge movements without the use of any expansion joints on the bridge superstructure. As the bridge superstructure expands and contracts due to seasonal thermal and other strains, relatively large forces can develop in the pile near the pile-cap interface. These reversible moment and shear forces can lead to localized damage near the top …

Multi-Segment Pile-Supported Bridge Approach Slabs For Control Of Differential Settlement, Ahmed Bahumdain

Theses and Dissertations

The roughness of the transition between the bridge and the roadway is a well-known issue that affects roughly 25% of the bridges in the United States. As soil underneath the approach slab settles, deferential settlement develops between the bridge and the approaching roadway. This may negatively affect the ride quality for travelers and result in substantial long-term maintenance costs. Because of the differential settlement, bumps could develop at the ends of the bridge when abrupt changes in slope (exceeding 1/125) occurs.

This study was aimed at mitigating the formation of bumps at the ends of the bridge through a new …

Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon

Theses and Dissertations

All travelers are exposed to the risk for crashes on the road, as none of the roadways are entirely safe. Under Vision Zero, improving traffic safety on our nation’s highways is and will continue to be one of the most pivotal tasks on the national transportation agenda. For decades, researchers and transportation professionals have strived to identify causal relationships between crash occurrence and roadway geometry, and traffic-related variables on the mission of creating a safe environment for the traveling public. Although great achievements have been witnessed such as the publication of the Highway Safety Manual (HSM), research is rather limited …

A Comprehensive Study On The Estimation Of Freeway Travel Time Index And The Effect Of Traffic Data Quality, Ambily Pankaj

Theses and Dissertations

Travel time reliability aims to quantify the variation of travel time by using the entire range of travel times for a given trip, for a selected time period over a selected horizon. A trip can occur over a segment, facility or any subset of the transportation network, for the purpose of calculating travel time reliability. As one of the most important performance measures, travel time reliability reports the number of trips that fail or succeed according to a predetermined standard. Unreliability is usually caused by the interaction of factors that influence travel times, such as fluctuations in demand due to …

The Effective Use Of Portland Cement In Reactive Powder Hybrid Asphalt Concrete, Clayton Cloutier

Theses and Dissertations

Today, building a durable and cost-efficient infrastructure while minimizing future repair needs is a challenging task, and innovative technological breakthroughs are needed. Limited research has been conducted to investigate the use of portland cement (PC) to improve the performance of asphalt pavements. Portland cement in bitumen materials is attractive as it can improve the performance and reduce costs. Warm Mix Asphalt (WMA) is also an attractive alternative to Hot Mix Asphalt (HMA) as this material produces tremendous energy savings by lowering the production temperatures and enhances certain performance characteristics. It can be envisioned that the use of portland cement incorporated …

A Comprehensive Study On The Estimation Of Freeway Travel Time Index And The Effect Of Traffic Data Quality, Ambily Pankaj

Theses and Dissertations

Travel time reliability aims to quantify the variation of travel time by using the entire range of travel times for a given trip, for a selected time period over a selected horizon. A trip can occur over a segment, facility or any subset of the transportation network, for the purpose of calculating travel time reliability. As one of the most important performance measures, travel time reliability reports the number of trips that fail or succeed according to a predetermined standard. Unreliability is usually caused by the interaction of factors that influence travel times, such as fluctuations in demand due to …