Travel demand has increased due to population growth, increase of vehicle ownership, and development patterns resulting in greater levels of congestion, pollution, and crash frequency. One approach to demand management is to increase the share of trips made by bicycles. With the increase in bicycling rates, there is a critical...
The safety of workers in the construction industry is a big concern because of the high number of fatalities and injuries that occur in the industry. Selecting contractors based on safety performance can improve safety and reduce the risks of injuries. However, owners commonly choose contractors based on competitive bidding...
Minimal research has focused on the social dimension of sustainability in the built environment especially as it relates to the construction workforce. As a result, there are few to no tools available to industry stakeholders to holistically assess and improve the social sustainability of the construction workforce. Given the high...
Thermodynamic modeling of cementitious material is an established tool for predicting the hydrated phase assemblages, pore solution pH, and pore solution composition of mixtures of various chemical compositions and water-to-binder (w/b) ratios. However, traditional thermodynamic techniques have major limitations for modeling mixtures containing supplementary cementitious materials (SCM), and when modeling...
The issue of chloride-induced corrosion of reinforcing steel in concrete and its economic impacts are well-known. Chlorides that cause reinforcement corrosion can be from constituent materials used to prepare concrete or can enter the hardened concrete when the structure is exposed to chloride environments. To minimize the risk of reinforcement...
While safety improvements have been made in the construction industry, construction still experiences one of the highest numbers of fatalities annually compared to other industries in the United States with over 970 fatalities in 2016 alone. This number of fatalities drives researchers and safety managers to improve safety measures and...
This work analyzes the numerical curvature of buckling braces. An existing brace modeling learning tool, which in its current state allows users to change the inputs within a simulated model of a braced element, was modified to display the curvature diagram. The curvature diagram was verified through comparison to existing...
This study focuses specifically on the investigation of a new, inexpensive geophone system and its application to monitor wave activity. Studies of seismic observations of coastal cliffs suggest that ground motions generated from local ocean waves may provide a surrogate to limited wave buoy data to quantify the wave contact...
Imagery acquired from unmanned aircraft systems (UAS) and processed with structure from motion (SfM) – multi-view stereo (MVS) algorithms provides transformative new capabilities for surveying and mapping. Together, these new tools are leading to a democratization of airborne surveying and mapping by enabling similar capabilities (including similar or better accuracies,...
The use of remote sensing techniques in coastal science and engineering has rapidly increased in the past few decades. This dissertation outlines new remote sensing tools using two remote sensing technologies (lidar and X-band marine radar) along with two nearshore hydrodynamic and morphodynamic analyses supported or motivated by these remote...
Accommodating motor vehicles that are turning (left or right) at signalized intersections requires a careful understanding of the safety and efficiency of design and operational variables. Turning vehicles are the primary collision risk for non-motorized road users at signalized intersections. When turning movements need to be controlled, proper driver response...
In the construction industry, people seek to deliver a successful project. The major success performance measurements in the construction industry are cost, time, and quality. Several researchers have determined critical success factors for construction projects, and one of these critical success factors was management actions. Furthermore, there is an inadequacy...
The two primary considerations for construction project management are budget and time management. Modular construction has the potential to improve construction productivity by minimizing time and costs while improving safety and quality. Cross-Laminated Timber (CLT) panels are beneficial for modular construction due to the high level of prefabrication, adequate dimensional...
Passenger security screening is a continuously evolving process and not much is known about how passengers perceive its effectiveness in keeping air travel safe. The provided thesis consists of two manuscripts that expand the literature on passenger perception of safety through the application of advanced econometric techniques. This thesis aims...
Design of Geosynthetic-Reinforced Soil Structures (GRSS) require sufficient rear pullout anchoring capacity in order to maintain internal stability. Length requirements are amplified when reinforcement coverage ratios or seismicity is considered, potentially resulting in uneconomical GRSS design lengths. This study describes the influence of reinforcement length, coverage ratio, and pseudostatic seismic...
Earthquake-induced liquefaction is a large contributor to damage observed following seismic events. Commonly observed damage consists of significant ground and structural failure due to the deformation of large volumes of soil due to soil liquefaction and lateral spreading. A significant focus of geotechnical seismic research concentrates on the development and...
Autonomous vehicles (AVs) at varying market penetrations will change traffic flow and highway performance. At AV market penetrations between 0% and 100%, human driven vehicles (HVs) will be interacting with AVs. However, little is known about how HVs interact with AVs. This study attempts to quantify HV headways when following...
Construction is a strategically important industry and its productivity has a significant impact on a nation’s economy. However, productivity in the US construction industry has been widely reported to be on the decline. Among several causes identified, the lack of innovation in project management practices has been described as having...
Interest in mapping bathymetry from multispectral satellite imagery has grown steadily since the 1970s. Notwithstanding the significant advancements made during this time, one limitation is that the group of algorithms collectively referred to as Satellite Derived Bathymetry (SDB) generally require “seed depths,” hindering their use for areas lacking reliable reference...
The tack coat bond is known to affect the longevity of asphalt pavements. Proper interlayer bonding prevents successive pavement layers from acting independently of one another and creating non-uniform stress and strain profiles in the pavement structure. Poor bonding between pavement layers can result in various pavement failures such as...
Over the decades, worker performance on construction projects has been a significant source of concern to be evaluated. Comprehensive studies have developed models for evaluating worker performance outside of the construction industry; however, minimal research has been conducted to evaluate worker performance in the construction industry. One of the reasons...
With rising sea levels and more frequent exposure to extreme storms, coastlines worldwide are vulnerable to increased erosion and loss of natural marsh lands. In an effort to lessen these impacts, there is a growing practice of adapting hard or “gray” coastline protection techniques to more nature-based features that promote...
Intersections pose unique transportation challenges regarding safety and operational efficiency. When pedestrians currently want to cross at intersection, they need to use a push button to issue a call for service. The call is static and cannot be altered or changed. But by implementing dynamic passive pedestrian detection sensors, intersections...
Debris generated after a disaster event must be disposed efficiently for community recovery. This is a significant operation that accounts for up to 27% of the total recovery costs. Generally, debris removal takes place in two phases: the short-term relief phase, which involves debris removal immediately after a disaster to...
As mass-timber building construction rises around the globe, there exists the need to verify the long-term, in-situ behavior and performance of these structural systems. Structural health monitoring (SHM), generally defined as a damage detection strategy consisting of a network of sensors, a data acquisition system, and algorithms for data analysis,...
A physical model study was performed to examine the forces and response of 1:6 scale wood-frame coastal residential structures subjected to storm surge and waves. An on-grade and an elevated specimen were tested and exposed to regular waves with varying water depths and wave heights to simulate Hurricane Sandy’s conditions....
The impact of tsunamis on coastal structures gained great a new impetus following the 2004 Indian Ocean Tsunami and the 2011 Tohoku earthquake and tsunami. While several experimental programs have been performed to gain a fundamental understanding, numerical models are needed to study additional features that cannot all be tested...
Public housing (PH) provides a substantial portion of the housing in both developed and less developed countries, and the demand for it is increasing. The PH projects, however, are facing many challenges that are affecting their performance and cause their failures. The United States has demolished large portions of their...
Mass timber is emerging as a viable form of construction around the world in new markets for wood buildings. The entrance into these markets has driven the demand for more knowledge to enable designs alongside other structural materials such as steel and reinforced concrete.
Large, in-plane tests on cross-laminated timber...
A typhoon is a highly destructive weather event, causing severe damage and losses to the economy and lives. The impacts of typhoons can be mitigated by adequately predicting their path in advance. The progress of a typhoon can be investigated by analyzing the significant changes in Precipitable Water Vapor (PWV)...
Geotechnical engineers design and analyze the interface between the natural and built environments, often based on uncertain and inherently variable data due to the nature of the building material, soil. Engineers must estimate the subsurface conditions at a site using historical, in-situ, and laboratory testing data. However, only discrete representative...
While primary use of Global Navigation Satellite System (GNSS) is positioning, navigation, and timing (PNT), various GNSS applications have emerged over the past decades that includes GNSS meteorology. GNSS meteorology is the remote sensing of the atmospheric constituents in the neutral atmosphere – mostly in the troposphere - using GNSS...
Coastal multi-hazards, i.e., earthquakes followed by tsunamis, induce severe damage to coastal infrastructure. The multi-hazards can cause soil liquefaction, which is one of the major concerns for evaluating sediments transport potential and structure failure mechanisms. The objectives for this work is threefold. First, to build and validate a soil numerical...
Timber-concrete composite (TCC) floors have improved strength and stiffness when compared to timber-only floors, allowing for longer spans in buildings and improved life safety. However, North America does not have codes and standards that recognize TCC floors, particularly the improved life safety performance of these floors in fire. Therefore, alternate...
Wildland-urban interface (WUI) communities, where forested land boundaries or intermixes with infrastructure, are quickly growing in the US. WUI communities have grown substantially from 1990 to 2010, with an increase of 12.7 million houses and 25 million people. Wildfires encroaching on WUI communities can cause damage to both above ground...
The constitutive behavior of high-performance fiber-reinforced cementitious composites (HPFRCCs) under mechanical loading is characterized by significant tensile properties that play an essential role in the structural response of several applications in structural engineering. The significance of tensile properties of HPFRCCs in structural engineering is the focus of three manuscripts presented...
Steel moment-resisting frames (MRFs) are widely used in the United States to resist seismic forces. MRFs have many advantages, including architectural versatility, vetted member and connection detailing requirements, and high ductility for special MRFs (SMRF). However, MRFs require large members to meet story drift criteria. Moreover, strong-column-weak-beam requirements can result...
Synthetic-aperture radar (SAR) imagery can provide wavenumber and frequency data to generate bathymetry estimates for locations where limited access or extreme ocean conditions can make standard bathymetry survey techniques difficult or impossible. The availability of SAR data could allow for regular bathymetry estimates of navigational channels providing insight into dredging...
The formation of beach scarps is a challenging morphodynamic phenomenon that the coastal community has yet to capture in coastal change models. Understanding scarp formation is crucial to accurately predicting coastal erosion and vulnerability during extreme events, as models without parameters for scarp formation and development severely underpredict total erosion...
Nonlinear response history analysis (NRHA) is increasingly becoming more accessible and prevalent in research and practice. As the accuracy of the NRHA results depends on the ground motion characteristics and the robustness of the numerical model, research has focused on the development of guidance for performance-based seismic design and assessment...
Cross-laminated timber (CLT) is revolutionizing the use of wood in the construction sector of North America as a solution for walls and diaphragms in mid-rise or even high-rise timber structures on account of its environmental advantages, high strength-to-weight ratio, fire-safety performance, and propensity for prefabrication. However, considering the hygroscopic nature...
This thesis presents two conceptually linked papers outlining methodologies to improve community resilience. Both papers employ Seaside, Oregon as a testbed community and consider the seismic-tsunami hazard posed by the Cascadia Subduction Zone. The first paper presents a framework to deaggregate the results of a multi-hazard, multi-infrastructure, damage analysis by...
Reliability-based geotechnical foundation design focusses on soil and structure analysis that meets necessary safety, performance and/or serviceability criteria, calibrated based on probabilistic analyses and an accepted level of risk. As the civil engineering community seeks to better harmonize geotechnical and structural design methodologies, reliability-based design is being incorporated more into...
Vertical datum is a reference system used for specifying the elevation of specific points on or near the Earth. Precise and accurate definition and realization of vertical references are, therefore, crucial to ensure consistency between height measurements. The vertical datums can be divided into two categories: 1) vertical geodetic datums...
Chloride binding in Portland limestone cements (PLC) can be attributed to the chemical reaction between chloride ions and carboaluminate phases to form Friedel’s salt and the physical interaction between chloride ions and calcium-silicate-hydrates (C-S-H). This thesis examines the chloride binding of mortar samples containing varying amounts of limestone, fly ash,...
Due to its availability, versatility, structural capability, and economic advantages, concrete is the most widely used material in building sewer networks and other wastewater structures such as treatment stations, wastewater digesters, septic tanks, pumping stations, hydraulic risers, utility risers and covers, etc. Concrete structures exposed to sewer environments can experience...
This dissertation studies the development of the design procedures for Steel Slit Panel Frame (SSPF). The (SSPF) system is a seismic force-resisting system (SFRS) with ductile behavior and good energy dissipation up to 5\% to 7\% lateral drift that acting as seismic fuses. The current design guidelines provided valuable information...
The rapid growth in the number of roundabouts raises some significant research challenges, especially around safety performance and evaluation in the U.S. Despite the safety advantages that roundabout geometric design brings, crashes still occur. While operationally roundabouts are good at preventing severe crashes, they may lead to more less severe...
Civil engineers are aware of the impacts of structures on the global environment but the environmental impacts of a fire within these structures remains unknown. Fires present a unique hazard as it is difficult to predict the probability of the occurrence and the intensity. Traditional methods to identify the environmental...
The seismic response of deep deposits of liquefiable and cyclic-softening susceptible soils has presented the geotechnical profession with significant engineering challenges. Strong ground motions may serve to soften soils under cyclic shear, trigger liquefaction, and produce damaging displacements as a consequence. This study improves the understanding of the in-situ, nonlinear,...