Different specimen preparation methods such as moist tamping, dry funnel deposition, slurry deposition, dry air pluviation have been reported in the literature to investigate the undrained behavior of silty sands. Similarly, different means have been used to densify the soils prepared with such methods. However, the influence of the densification...
This dissertation presents the results of a research effort conducted to better understand the stress-strain, volume change, shear band formation, and strength characteristics of normally consolidated anisotropic clay under fully three-dimensional stress states. A series of consolidated drained true triaxial tests with a constant mean effective stress and constant Lode...
Pile supported bridges are typically constructed near or in a natural or man-made
slope and are subjected to lateral loading. The current design method for laterally loaded
piles involves the use of Winkler's spring concept with the standard nonlinear p-y curves.
The available p-y curves were developed based on results...
In this dissertation the interactions between hydrodynamics, sediment suspension and transport, and morphological evolution in the surf zone was investigated with a large-scale laboratory experiment data, CROss-Shore Sediment Transport Experiment (CROSSTEX). The data set included comprehensive measurements of water surface elevation, fluid velocity, sediment concentration, and morphology for irregular waves...
Halogenated organic compounds have had widespread and massive applications in industry, agriculture, and private households, for example, as degreasing solvents, flame retardants and in polymer production. They are released to the environment through both anthropogenic and natural sources. The most common chlorinated solvents present as contaminants include tetrachloroethene (PCE, perchloroethene)...
Posting advisory speed signs at sharp horizontal curve sites is a practice well established in the United States. The purpose of these signs is to provide the driving public with a safe speed to negotiate such curves; however, the link between these signs and safety has not yet been clearly...
It has been suggested that projects in the construction industry are subject to risks more than other industries. However, there is often little parity in allocation of risks in the construction industry. Usually, project participants allocate risks by aversion where owners tend to shift risks to the primary contractor, who...
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...
The trenchless technology known as pipe ramming for construction of culverts and buried pipes under roadways or other infrastructure has gained significant popularity due to its cost-effectiveness and ability to alleviate surface disruptions associated with open-cut trenching. Although the experience with pipe ramming is increasing, there has been remarkably little...
To better understand the extreme local amplification of tsunami, the experimental investigation on counter-propagating solitary wave collisions over a horizontal bottom was conducted using the optical measurement techniques: Particle Image Velocimetry (PIV), and Laser Induced Fluoresce (LIF). Head-on collisions and oblique collisions of equal-amplitude as well as unequal-amplitude waves were...
In the field of civil infrastructure, bridge desks are typically constructed using high performance concrete (HPC). Concrete bridge decks demand qualities such as low permeability, high abrasion resistance, superior durability, and long design life. Over decades of field and laboratory experience, many HPC bridge decks have been found to be...
The construction industry employs about 7% of the total US workforce, and yet it accounts for 15.7% of all occupational fatalities. Specifically in 2011, there were 721 deaths in construction, second only to transportation with 733. The cause of a large number of these construction deaths can be attributed to...
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 dissertation examines tsunami and hurricane wave loads on bridge superstructures. Tsunamis have caused significant damage to coastal communities in recent years. For example, the 2011 Great East Japan Earthquake and resulting Tohoku Tsunami destroyed infrastructure along the east coast of Japan including bridge superstructures. Recent hurricanes have also caused...
The production of cement and concrete results in the production of large amounts of CO₂ emissions which can have significant negative environmental impacts. Using supplementary cementing materials (SCMs) as a cement replacement is an effective solution to reduce these negative environmental impacts, as most SCMs are waste by-products from other...
Deep foundations are necessary for the construction of many structures, such as bridges and buildings, located in areas unsuitable for shallow foundations. Owing to the inherent variability of soil and the complex changes that occur in the soil adjacent to deep foundations as they are installed, the ability to accurately...
Discrete columns, such as stone and soil-cement columns, are often used to improve the liquefaction resistance of loose sandy ground. In particular, stone columns are considered to increase resistance potential by densification, drainage, and reinforcement mechanisms. For silty soil, the shear stress reduction resulting from the reinforcing effect of stiffer...
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...
Traffic signal countdown timers (TSCT) are innovative, practical and cost effective technologies with the potential to improve efficiency and safety at signalized intersections. The purpose of these devices is to assist motorists in decision making at signalized intersections with real time signal change information. While successful implementation of these devices...
To facilitate the evaluation and design of structures subjected to fluid loading, a study of fluid-structure interaction (FSI) using the particle finite element method (PFEM) is presented to approximate the responses and sensitivities of structures which interact with fluid. A wide range of structural types are permissible by making no...