Many publications, documents, codes and guidelines exist related to the seismic evaluation and rehabilitation design of existing buildings. This report discusses the assumptions and methods employed for investigation of two wood structures using four references: FEMA 154, FEMA 356, ASCEI per SEI 31, and 1997 UBC. The screening performed using...
1,1,1-Tricholorethane (1,1,1-TCA), a widely used industrial solvents, is one of the most common subsurface contaminants. Transformation processes in the subsurface can result in the production of 1,1-dichioroethane (1,1-DCA) and 1,1- dichioroethene (l,1-DCE) from 1,1,1-TCA contamination, resulting in plumes of mixed chlorinated aliphatic hydrocarbons (CAHs). A butane-utilizing microorganism, strain 1 83BP,...
Large numbers of 1950's vintage conventionally reinforced concrete (CRC) bridges remain in-service in the national bridge inventory. Many of these bridges are lightly reinforced for shear. Evaluation of these bridges to prevent unnecessary and costly repairs requires refined analytical techniques. This dissertation presents finite element (FE) modeling and comparisons of...
The Asphalt Pavement Analyzer (APA) device was used to characterize the impact of various mix factors on the development of permanent deformation in dense-graded mixes given a standard compactive effort. Factors included two aggregate sizes, three VMA levels, two fines contents, three binder contents and four binder types. All specimens...
The cyclic resistance of predominantly fine-grained soils has received considerable attention following ground and foundation failures at sites underlain by silt-rich soils during recent earthquakes. In several cases substantial ground deformation and reduced bearing capacity of silt soils has been attributed to excess pore pressure generation during cyclic loading. These...
A numerical model for the simulation of fully-coupled fluid-structure
interaction is developed in this study. In modeling the fluid, the Reynolds
Averaged Navier-Stokes equations are solved for an incompressible viscous
fluid field and a k-ε model is employed for turbulence computations.
Hydrodynamic forces obtained by the integration of the fluid...
Performance evaluation of conventionally reinforced concrete (CRC) bridge superstructure elements with diagonal cracks is of interest to the bridge engineering community. Standardized methods to predict service-level stress magnitudes in cracked bridge girders under combined bending and shear forces are not available. An analysis procedure was developed to determine the response...
Assessment of an existing bridge is needed when the structure exhibits signs of distress. Assessment practices require refinement in the calculation of loading and resistance while maintaining an acceptable level of risk, to minimize costs associated with repair, replacement and weight restrictions. Previous risk-based assessments evaluated the strength cases for...
The transformation of 1,1,1 -trichioroethane (1,1,1 -TCA) and 1,1 -dichioroethene (1,1 -
DCE) was evaluated in a continuous flow column reactor using a mixed culture that grew
on butane. The column was packed with aquifer materials and groundwater obtained
from the in-situ bioremediation test site at Moffett Field, CA. The...
Uranium adsorption to Hanford sediment was studied for various pH, total inorganic carbon concentrations, and total U(VI) concentrations. Both batch and transport studies were done in an attempt to understand the adsorptive trend of U(VI) on Hanford sediment, and the changes in adsorption as both pH and total inorganic carbon...
The objectives of this study were to evaluate the performance of wood frame shear walls
under monotonic, cyclic and earthquake loads by: (1) estimating the variability of shear wall
performance, (2) comparing the performance of walls under each loading protocol, (3) evaluating
the effects of anchorage on wall performance, and...
Structural design codes have evolved continuously since modern codes were established. The allowable stress design format has been widely used since the late 191h century. During the past two decades, probability-based limit states design concepts have evolved and are increasingly being used for various material and structural types. Limit state...