A numerical model, simulating the complex behavior of reinforced soil walls using the finite element method, was developed to evaluate the behavior of a surcharged, geosynthetic-reinforced retaining wall with modular block facing. A nonlinear elastic-plastic constitutive soil material model was calibrated to experimental plane strain test data, while the performance...
Radiation stresses, defined as the excess flow of momentum due to the presence of waves (Longuet-Higgins, 1964), are the main drivers behind the cross-shore and longshore forcing that results in wave setup, set-down, and longshore currents (e.g. Svendsen, 2006). Longshore currents entrain and transport sediment and therefore play an important...
Large numbers of reinforced concrete deck girder (RCDG) bridges were built during the highway infrastructure boom of the 1950's. The advent of standardized deformed steel reinforcing bars during this time allowed for straight bar terminations in flexural tension regions. Designers of the time terminated reinforcing bars where they were no...
Many older reinforced concrete deck girder (RCDG) bridges contain straight bar terminations of flexural reinforcement. Common bridge design practice of the 1950s did not consider the additional demands on the terminated bars from shear and flexure. Moreover, more stringent code specifications and heavier permit trucks contribute to the insufficient ratings...
Surf zone eddies (f < 0.01 Hz) are important in nearshore mixing, shoreline erosion, the distribution of pollutants, and ecological processes, such as offshore transport of larvae. Surf zone eddies have traditionally been treated as two-dimensional features with horizontal length scales larger than the local water depth. Studies by Lippmann...
The collapse of the I-35W Bridge in Minneapolis, MN in 2007 prompted an investigation into the design and inspection of the steel truss bridges. Further investigation into the collapse revealed that a gusset plate experienced sway buckling, causing the bridge failure. This bridge failure motivated research into the analysis and...
Most specifications for ready-mix concrete (RMC) limit mixing time to 90 minutes and/or truck drum revolution counts (DRC) to 300 before discharge. These specifications have been in place for many years with the objective of ensuring the quality and performance of the finished concrete product. However, limited research has been...
During the 2011 Great East Japan Earthquake and Tsunami, numerous bridge structures were damage or destroyed. The damage to bridge systems was caused by long duration strong ground shaking, tsunami inundation forces, or both. Long duration strong ground shaking from subduction zone earthquakes and the multi-hazard scenario of combined earthquake...
Global climate change is expected to exaggerate the severity of floods and droughts and increase the frequency of extreme streamflow events in the Midwestern United States. Managing these projected impacts poses a major challenge for water resources, conservation, and land use management. Wetlands have been considered as a conservation strategy...
Estuaries represent the confluence of land and ocean environments and encompass a number of complex interactions amongst tides, winds, offshore waves and the riverine contributions, all of which contribute to total water levels (TWLs). The study of TWLs and the relative weight of its components can assist local communities in...
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...
High Performance Concrete (HPC) is used in our crucial pieces of infrastructure, such as bridge decks, due to its enhanced durability and engineering properties. However, HPC is highly susceptible to early-age cracking. Cracking within the first months of a bridge deck’s lifespan can severely hinder its long-term performance and durability....
The research presented in this thesis assessed the use of high strength steel (HSS) reinforcement for use in reinforced concrete (RC) bridge columns. HSS is not currently allowed in reinforced concrete bridge columns due to a lack of information on the material characteristics and performance information when used in RC...
Concrete formwork is a common type of temporary structure used on construction projects. Due to difficulties in considering actual construction site implications during formwork design, assessments of formwork integrity are often made in the field by site personnel based on subjective visual inspection. The use and re-use of concrete formwork...
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...
The number of international inbound tourists to the United States has risen steadily. To serve these and other tourists best, traffic signs need to communicate information correctly across a potential language barrier. Of particular interest is the traffic sign intended to communicate directions to Tourist Information centers. While the general...
Tsunamis have the potential to inflict severe damage and loss of life in coastal communities. Structures known as vertical evacuation buildings provide an alternative evacuation site for communities living in relatively flat, coastal regions with inadequate sources of high ground for evacuation. Design of these structures balances risk and economy,...
Engineered wood composites are used in many structural applications and are intended for dry use. However, these materials may encounter significant amounts of wetting while in service, which can lead to structural failures. This study combined aspects of wood science, mechanics, structural engineering, and mycology to assess changes in material...
The production of high value non-conventional products, such as long utility poles; or the production of low value bulky products, such as chips or grindings; provide opportunities for forest owners to increase value from their forests. The transport of these products requires the use of specialized trucks and trailers. However,...
The development of cross-laminated timber (CLT) panel technology has opened up new opportunities for wood in tall buildings. Several characteristics including seismic performance and speed of construction have raised interest among designers. As CLT gains acceptance in the industry, alternative structural solutions need to be investigated to improve performance of...