Attention has been drawn to the observation that environmental benefits under the current regulatory approaches are diminishing with respect to increased pollution control costs. Regulators have begun to appreciate that while environmental gains can still be achieved under the current command and control system, the most significant environmental gains have...
This study consists of three parts: 1) Part A: Limiting Height Evaluation for
Composite Wall Tests, 2) Part B: Mid-Span Deflection Evaluation for Composite Wall
Tests, and 3) Part C: Nominal Axial Strength Evaluation for Wall-Braced Wall Stud
Columns.
The purpose of Part A is to develop experimentally-based limiting heights...
The mixed metal compound, Chromated Copper Arsenate, or CCA, has been widely used as a wood preservative. The metal ions in CCA, CrO²⁻₄, Cu²⁺, and AsO³⁻₄, have been found in contaminated surface and subsurface soils and groundwater nearby some wood preservative facilities and nearby wood structures. Iron oxides are a...
The research presented here is a study to determine the effect of shear reinforcement corrosion on the shear capacity in conventionally reinforced concrete (CRC) bridge elements. A total of 14 CRC beams were tested using three stirrup spacings (8, 10, and 12-inch). Six of the beams included the influence of...
The 1,1-dichloroethene (1,1-DCE) cometabolic transformation abilities of indigenous and bioaugmented microorganisms were compared in microcosms constructed with groundwater and aquifer solids from the Moffett Field site, CA. Microbial community structure in the microcosms and possible community shifts due to 1,1-DCE transformation stress was evaluated by terminal restriction fragment length polymorphism...
This study investigated the use of radon-222 as an in situ partitioning tracer for quantifying nonaqueous phase liquid (NAPL) saturations in the subsurface. Laboratory physical aquifer models (PAMs), field experiments, and numerical simulations were used to investigate radon partitioning in static (no-flow) experiments and in single-well, 'push-pull' tests conducted in...
The goal of this research was to mathematically simulate the ability of bioaugmented microorganisms to aerobically cometabolize a mixture of chlorinated aliphatic hydrocarbon (CAH) compounds during in-situ treatment. Parameter values measured from laboratory experiments were applied to the transport model with biotransformation processes included. In laboratory microcosm studies, a butane-grown,...
The present research investigates nonlinear barge motions through analyses of coupled multi-degree-of-freedom (MDOF) deterministic and stochastic models. Roll-Heave-Sway and other lower-ordered models are developed to predict the nonlinear motions and analyze the stability of a class of ship-to-shore cargo barges. The governing equations of motion contain coupled rigid body Roll-Heave-Sway...
Laboratory and modeling studies were performed with a mixed-anaerobic-culture obtained from the Evanite site in Corvallis, Oregon. The culture completely transforms trichloroethene (TCE) to cis-dichloroethene (c-DCE), vinyl chloride (VC), and finally to ethene. Acetylene inhibition studies were used to examine the culture's microbial activities. Kinetic studies determined the half-saturated constant...
On August 31, 1992, Quality Printing Circuits, a circuit board manufacturing plant in Phoenix, Arizona, burned to the ground. The fire lasted approximately eight hours, creating a thick, black smoke that blew into the surrounding community. Emergency evacuation was erratic and since no air samples were taken during the fire,...