Fire hazards threaten human life and property safety. Since it is unrealistic to study human behavior during a real fire hazard, computational tools are a better choice to computational tools are a better choice to simulate fire growth and human behavior for predicting evacuation performance in chaotic emergency situations. Although...
Chloride-induced corrosion is one of the primary causes of the degradation of reinforced steel in concrete structures. Currently, the rapid chloride permeability test (RCPT) is the most specified method to determine the concrete’s resistivity to chloride ingress, thus a determining factor in assessing the durability of concrete. While it is...
Previous research has shown that using fine lightweight aggregate (FLWA) can be a promising strategy to mitigate alkali-silica reaction (ASR) in mortar and concrete. While several possible theories were proposed by researchers, discrepancies in testing methods, materials, and supporting evidence still exist. Therefore, this study was initiated. There are two...
Aggregate piers have been used for centuries, with increasing occurrence in the last few decades. Their usage has been driven by land development demand and enabled through equipment and engineering improvements. Understanding the principles controlling bearing capacities and serviceability performance has been an ongoing area of interest for structures supported...
Unmanned aircraft systems (UAS), also known as drones, are an increasingly popular method of collecting surveying and mapping data. Two common drone-based mapping techniques are lidar and structure from motion (SfM) photogrammetry, and a frequently-heard (yet nearly impossible to answer) question is: “which is better?” The most common metric for...
Bio-cementation is a promising method for the liquefiable mitigation of loose saturated sands. In the improvement process a bacterium that can be found naturally in soil deposits is fed urea. The bacterium consumes and breaks down the urea to form ammonium and carbonate. In the presence of calcium, calcium carbonate...
This thesis presents a novel approach for propagation of uncertainty in river systems. Errors in data observations and predictions (e.g., stream inflows), in model parameters, and resulting from the discretization of continuous systems, all point to the need to accurately quantify the amount of uncertainty carried through the modeling process....
In this study, a coupled potential flow-viscous flow model is used for numerical wave tank simulation. The solver satisfies all the requirements for such a simulation environment. The coupling scheme is based on a non-overlapping heterogeneous domain decomposition method. In this method, the flow domain consists of two subdomains. In...
This thesis presents an analytical, experimental and numerical study of the initiation of flows in a siphon for rapid and gradual openings of a downstream valve. Three initial water levels in the upstream tank and four final positions for the downstream valve were investigated. Two opening times of the downstream...
State Departments of Transportation (DOTs) are the primary owners of roadway infrastructure in the United States. Many of the employees of state DOTs work on roadway work sites, putting them at disproportionately higher risks of injury or fatality. A review of the literature determined that a combination of policies, standards,...
Improving safety education could contribute to the preparation of better professional engineers. Safety topics are not holistically embedded in transportation course curricula. This thesis explores the current state in which safety is being incorporated in transportation course curricula in terms of design and compares the uses of safety data in...
Driving simulation is widely accepted as a safe, effective, and economical alternative for investigating driver behavior in a variety of contexts. However, in order to apply simulator-based research results to real-world settings, the performance measures acquired through simulated driving experiments must first be validated. This research was aimed at validating...
Three-dimensional laser scanning has revolutionized spatial data acquisition and can be completed from a variety of platforms including airborne (ALS), mobile (MLS), and static terrestrial (TLS) laser scanning. MLS is a rapidly evolving technology that provides increases in efficiency and safety over static TLS, while still providing similar levels of...
Real time networks (RTNs) have become popular for Global Navigation Satellite System (GNSS) surveys because highly accurate positions can be derived in seconds to minutes compared to hours as required with static sessions. To evaluate the accuracy of these shorter-duration, RTN GNSS observations and their potential for use as a...
The response of adjacent structural systems to earthquake motions is investigated using the finite element framework OpenSees. Results of sensitivity analyses demonstrate that structural response quantities can increase in either or both of the adjacent structures for specific configurations. The structural models used include steel moment-resisting frames and rigid shear...
Natural disasters could result in unnecessary loss of life and disproportionate suffering to families and communities if evacuation plans are not in place or understood by the public. In the Pacific Northwest, a magnitude 9.0 earthquake and tsunami from the Cascadia Subduction Zone (CSZ) represents one of the most pressing...
The M9 Cascadia subduction zone earthquake represents one of the most pressing natural hazard threats in the Pacific Northwest of the USA with an astonishing high 7–12% chance of occurrence by 2060, mirroring the 2011 devastating earthquake and tsunami in Japan. Yet this region, like many other coastal communities, is...
Using recycled concrete aggregate (RCA) as a replacement for natural aggregate in new concrete is a promising way to increase the overall sustainability of new concrete. This has been hindered, however, by a general perception that RCA is a sub-standard material due to the lack of technical guidance, specifically related...
Reflection of an obliquely incident solitary wave at a vertical wall is studied experimentally in the laboratory wave tank. Precision measurements of water-surface variations are achieved with the aid of laser-induced fluorescent (LIF) technique and detailed temporal and spatial features of the
Mach reflection are captured. During the development stage...
Increasingly congested surface transportation network in urban areas and grow-ing land values make underground transportation systems more attractive for high-ways (i.e., tunnels) and metro system compared to other options [1]. An underground transportation system can preserve the land above for recreational parks, commer-cial buildings, residential homes, or other purposes while...
This thesis is comprised of two manuscripts based on a laboratory experiment conducted to examine realistic wave forcing on a vertical wall subjected to tsunami loading. The first manuscript examined tsunami force and pressure distributions on a rigid wall that was fronted by a small seawall. Six different seawall heights...
This paper presents a parallel implementation and validation of an accurate and efficient three-dimensional computational model (3D numerical wave tank), based on fully nonlinear potential flow (FNPF) theory, and its extension to incorporate the motion of a laboratory snake piston wavemaker, as well as an absorbing beach, to simulate experiments...
The two primary considerations for highway work-zones are its effect on commuter mobility and worker safety which are often spoken of together. However, it must be noted that they often conflict with each other. For example, traffic control plans that reduce travel speed in work-zones improve both commuter and worker...
Gap acceptance behavior is critical to the safety and operational performance of unsignalized intersections. The complex nature of the human behavior and its dependence on various socioeconomic and environmental parameters makes it challenging for transportation professionals to assess the performance of such intersections. To investigate the behavioral patterns of drivers...
This thesis provides a comparison of advanced econometric frameworks to account for unobserved factors in crash reported data (also referred to as unobserved heterogeneity) while identifying contributing factors by roadway classification for heavy vehicle injury severity and crash rates. The presented thesis provides two manuscripts that expand the literature regarding...
The implementation and construction of Mechanically Stabilized Earth (MSE) walls has undergone substantial expansions in recent years, owing to its relatively low cost, ease of construction, and high efficiency compared to conventional retaining methods. As a result, MSE walls are being constructed to greater heights with complex features (e.g. multiple...
A Geyser in a stormwater (SW) and combined sewer system (CSS) is an oscillatory and violent release of a mixture of air and water through vertical shafts. Violent geysers are highly destructive. In the case of combined sewer systems, many municipalities operate their systems at a fraction of their maximum...
Student engagement has been the focus of much engineering education research, in large part due to its ties to student learning. Widely considered to be a meta-construct, student engagement is often broken down into behavioral, emotional, and cognitive components. Reasons for ongoing research on student cognitive engagement are twofold: educators...
Landslides are a pervasive hazard that can result in substantial damage to properties and loss of life throughout the world. To understand the nature and scope of the hazard, landslide hazard mapping has been an area of intense research by identifying areas most susceptible to landslides in order to mitigate...
Oregon State University conducted a series of laboratory experiments to measure and quantify the near-field wave effects caused within arrays of Wave Energy Converters (WEC). As the waves and WECs interact, the WECs generate radiated waves; these effects vary with the location within the array. Analyzing the near-field waves will...
Structurally efficient and cost-effective solutions are needed to extend the service-life of deficient and aging highway infrastructure around the world. One critical need is to increase the flexural strength of older reinforced concrete (RC) structures to carry heavier and more frequent loads. Titanium alloy bars (TiAB) offer a new opportunity...
In the light of the changing climate, the importance of designing effective watershed management plans that are likely to be implemented is becoming ever more important. This research introduces a new concept, consensus, for incorporation into stakeholder-guided interactive optimization of watershed management plans. User preferences were mathematically simulated based upon...
The goal of the first part of this project was to investigate the influence of aggregate source and entrained air on the transport properties of concrete. Currently, there are several ASTM standards available that provide systematic procedures to evaluate mass transport properties of concrete. ASTM C642-13 (ASTM 2013), often referred...
The first goal of this master’s thesis was to investigate the linkage between a non-destructive testing method, surface resistivity, and premature concrete deterioration brought on by chloride ingress and or freeze-thaw cycling. The experimental method for this project consists of taking surface resistivity measurements of reinforced concrete slabs after they...
Corrosion of reinforcement is recognized as the predominant factor that limits the service life of reinforced concrete (RC) structures exposed to aggressive environments. This corrosion deterioration can lead to damage resulting in capacity loss or even failure. For structures exposed to coastal marine environments or deicing or anti-icing applications, this...
Bioretention facilities are emerging as a popular way to deal with stormwater runoff in urban environments and address its concerns. Real-time sensors installed in bioretention facilities aid in understanding the performance and feasibility of such facilities over time. A bioretention facility in Corvallis, Oregon was monitored for a study period...
The Large Wave Flume at the O.H. Hinsdale Wave Research Laboratory houses a piston wavemaker with a built-in active absorption system designed by MTS Systems Corporation. The performance of the active absorption system has not been properly assessed yet. This thesis evaluates the performance of the MTS active absorption system...
Numerical models are effective tools for simulating complex physical processes such as hydrodynamic and water quality processes in aquatic systems. The accuracy of the model is dependent on multiple model parameters and variables that need to be calibrated and regularly updated to reproduce changing aquatic conditions accurately. Multi-sensor water temperature...
Shallow foundations are extensively used to support structures of all sizes and derive their support from near surface soils. Thus, they are typically embedded up to a few meters into the soil profile. Designers of shallow foundations are required to meet two limit states: overall failure of the soil beneath...
Pile caps are structural elements used to transmit loads from structural columns into pile groups. A pile cap is generally constructed of reinforced concrete and contains only minimal flexural reinforcing steel. Using modern design methods, the anchorage of the flexural steel may limit the design capacity of existing pile caps....
Open grid steel bridge decks have been in use for nearly a century. These open grid decks provide an economical and lightweight alternative to traditional reinforced concrete decks. As the transportation infrastructure continues to deteriorate, open grid decks can be used as a cost effective way to rehabilitate structurally deficient...
Nearly all soils are comprised of mixtures of coarse and fine particles. Behavior under mechanical and thermal loading of soil is strongly influenced (and in some cases, governed) by the ratio of coarse to fine particles. A better understanding of the fundamental behavior of soil mixtures will provide insight to...
Vegetation at the aquatic–terrestrial interface can alter landscape features through its growth and interactions with sediment and fluids. Even similar species may impart different effects due to variation in their interactions and feedbacks with the environment. Consequently, replacement of one engineering species by another can cause significant change in the...
The blast technique has been used as an effective soil improvement method to compact loose coarse-granular soils since 1930s, and the use of the blast technique is extended as an application of in-situ liquefaction testing to investigate the performance of full scale foundations and countermeasures against liquefaction in recent decades....
Boulder transport models have been used to develop a historical record of hydrodynamic events. This is done by evaluating the size, location, and composition of boulders that have been removed from their region of formation. Boulder transport is difficult to predict, even under laboratory conditions.
Experiments were conducted to evaluate...
In the presence of strong winds, ocean surface waves dissipate significant amounts of energy by breaking. Here, breaking rates and wave-following turbulent dissipation rate measurements are compared with numerical WAVEWATCH III estimates of bulk energy dissipation. At high winds, the measurements suggest that turbulent dissipation becomes saturated, however the modeled...
The Pacific Northwest is at risk for significant seismic and tsunami events, which are capable of severely damaging lifeline transportation infrastructure, particularly bridges. As the bridges in the United States age and begin to show signs of fatigue, the risk for severe damage increases. Proper monitoring and inspection of bridges...
Bridge inspection is a critical task needed to monitor bridge quality and serviceability. In the U.S., 40% of bridges are more than 50 years old while most bridges are typically designed for a lifespan of 50 years. 9.1% of the 614,387 bridges across the U.S are considered structurally deficient. These...
The aim of this research is to understand and quantify the modeling differences between CSiBridge and OpenSees, and to determine sensitive model parameters. When designing bridges for the high seismic region of California, the California Department of Transportation (Caltrans) performs nonlinear time history analysis of their bridge models. For three-dimensional...
Soil instability from tsunami hazards causes substantial damage to coastal infrastructure (e.g., the damage caused by the 2011 Great East Japan Tsunami, or the Heisei Tsunami). Tsunamis are unpredictable, so it is difficult to obtain field-scale measurements. Simulating tsunamis in a laboratory setting is therefore important to further understanding of...