Wearing Surface Testing and Screening: Yukon River Bridge

There is a demand and a need for cheaper and alternative surface coverings in environments with high temperature fluctuations. Our design for an alternative surface covering involves a basic twopart component epoxy with the addition of a solvent. The purpose of the solvent is to disrupt the reaction that forms the ordered chains to form a more disordered crystalline structure. The solvent in the finished product is 3% by volume of isopropyl alcohol. This mixture of epoxy and solvent has higher impact strength than epoxy alone, as well as a much lower brittle transition temperature of 27°C compared with 10°C for epoxy. An environmental chamber, tensile tester, Charpy impact tester, and 4- point bending test were used to determine these conclusions. The final product can be tailored with different aggregates to fit a specific need, such as decking surface material to coat the wooden planks on the Yukon River Bridge.Table of Contents Table of Figures ............................................................................................................................................. ii List of Tables ................................................................................................................................................ iii Abstract ........................................................................................................................................................ iv Executive Summary ....................................................................................................................................... v 1. Introduction .............................................................................................................................................. 1 1.1 Yukon River Bridge Project 2006 ......................................................................................................... 1 1.2 Yukon River Bridge 2011 ..................................................................................................................... 3 2. Scope of Work ........................................................................................................................................... 3 Part 1 ......................................................................................................................................................... 3 Part 2 ......................................................................................................................................................... 3 3. Test Results and Data ................................................................................................................................ 4 Part I .............................................................................................................................................................. 4 3.1 Project Basis ........................................................................................................................................ 4 3.2 Methodology ....................................................................................................................................... 6 3.3 Results/Future Work ........................................................................................................................... 6 3.3.1 Charpy impact tests ..................................................................................................................... 6 3.3.2 Tensile tests ................................................................................................................................. 9 3.4 Chemical Theory ............................................................................................................................... 11 3.5 Facilities............................................................................................................................................. 14 3.6 Materials Tested ............................................................................................................................... 16 Part II: .......................................................................................................................................................... 18 3.7 Collecting Data .................................................................................................................................. 18 3.7.1 Determining percent isopropyl alcohol (Figure 19) ................................................................... 18 3.7.2 Determining the number of seal coatings (Figures 21–25) ....................................................... 19 3.7.3 Wear testing ............................................................................................................................... 24 3.7.4 Application process on test planks ............................................................................................ 25 3.7.5 Conclusion of information gathered from collecting data......................................................... 30 3.8 Modification Made to the Planks ...................................................................................................... 30 4 What Went Wrong in the Experiment ..................................................................................................... 30 5 What Could Be Changed, Future Modifications....................................................................................... 31 References .................................................................................................................................................. 32 Table of Figures Figure 1: Yukon River Bridge. ........................................................................................................................ 1 Figure 2: ASTM standards. ............................................................................................................................ 5 Figure 3: Epoxy samples – temperature rise vs. impact strength. ................................................................ 7 Figure 4: Epoxy with kerosene samples – temperature rise vs. impact strength. ........................................ 8 Figure 5: Epoxy with isopropyl alcohol samples – temperature rise vs. impact strength. ........................... 8 Figure 6: Epoxy with isopropyl alcohol and sand samples – temperature rise vs. impact strength. ........... 9 Figure 7: Epoxy samples – extension vs. load. ............................................................................................ 10 Figure 8: Epoxy with isopropyl alcohol samples – extension vs. load. ....................................................... 10 Figure 9: Epoxy with acetone samples – extension vs. load. ...................................................................... 11 Figure 10: Basic structures in epoxy. .......................................................................................................... 11 Figure 11: First step of polymerization. ...................................................................................................... 12 Figure 12: Long chain epoxy molecule ........................................................................................................ 12 Figure 13: Epoxy mixed with acetone solvent ............................................................................................ 12 Figure 14: Alcohol and ketone reaction. ..................................................................................................... 13 Figure 15: Epoxy hydrogen bonding with isopropyl alcohol. ...................................................................... 13 Figure 16: Environmental chamber used to freeze the samples. ............................................................... 14 Figure 17: Instron tensile test apparatus. ................................................................................................... 15 Figure 18: Charpy ........................................................................................................................................ 15 Figure 19: Test samples 3–5%, 10%, 20% isopropyl alcohol. ...................................................................... 18 Figure 20: Resistance to moisture migration. ............................................................................................. 19 Figure 21: Test samples: no sealing, 1 sealing, 2 sealings, and 3 sealings submerged in water. ............... 21 Figure 22: (Weight/dry weight) vs. days boards soaked............................................................................. 22 Figure 23: (Weight/dry weight) vs. days boards soaked............................................................................. 22 Figure 24: Percent increase in weight vs. number of seal coatings. ........................................................... 23 Figure 25: Percent increase in weight vs. number of seal coatings. ........................................................... 24 Figure 26: Traction and wear test equipment. ........................................................................................... 25 Figure 27: Epoxy sample after the wear test. ............................................................................................. 25 Figure 28: Laying out bolt pattern. ............................................................................................................. 26 Figure 29: Drilling countersunk holes. ........................................................................................................ 24 Figure 30: Completed board though application process. ......................................................................... 26 Figure 31: Bur on PVC pipe ......................................................................................................................... 27 Figure 33: Planks drying after sealing ......................................................................................................... 27 Figure 34. Plank preparation before aggregate application. ...................................................................... 28 Figure 35: Planks drying. ............................................................................................................................. 29 Figure 36: Removing tape and cotton balls. ............................................................................................... 29 Figure 37: Chip in plank ............................................................................................................................... 29 Figure 38: Chip patched .............................................................................................................................. 29 Figure 39: Additional chip patched ............................................................................................................. 3

The Effects of Fire on the Function of the 200-BP-1 Engineered Surface Barrier

A critical unknown in use of barrier technology for long-term waste isolation is performance after a major disturbance especially when institutional controls are intact, but there are no resources to implement corrective actions. The objective of this study was to quantify the effects of wild fire on alterations the function of an engineered barrier. A controlled burn September 26, 2008 was used to remove all the vegetation from the north side of the barrier. Flame heights exceeded 9 m and temperatures ranged from 250 oC at 1.5 cm below the surface to over 700 oC at 1 m above the surface. Post-fire analysis of soil properties show significant decreases in wettability, hydraulic conductivity, air entry pressure, organic matter, and porosity relative to pre-fire conditions whereas dry bulk density increased. Decreases in hydraulic conductivity and wettabilty immediately after the fire are implicated in a surface runoff event that occurred in January 2009, the first in 13 years. There was a significant increase in macro-nutrients, pH, and electrical conductivity. After one year, hydrophobicity has returned to pre-burn levels with only 16% of samples still showing signs of decreased wettability. Over the same period, hydraulic conductivity and air entry pressure returned to pre-burn levels at one third of the locations but remained identical to values recorded immediately after the fire at the other two thirds. Soil nutrients, pH, and electrical conductivity remain elevated after 1 year. Species composition on the burned surface changed markedly from prior years and relative to the unburned surface and two analog sites. An increase in the proportion of annuals and biennials is characteristic of burned surfaces that have become dominated by ruderal species. Greenhouse seedling emergence tests conducted to assess the seed bank of pre- and post-burn soils and of two analog sites at the McGee Ranch show no difference in the number of species emerging from soils collected before and after the fire. However, there were fewer species emerging from the seed bank on the side slopes and more species emerging from two analog sites. Leaf area index measures confirmed the substantial differences in plant communities after fire. Xylem pressure potential were considerably higher on the burned half of the barrier in September 2009 suggesting that not all the water in the soil profile will be removed before the fall rains begin. The results of this study are expected to contribute to a better understanding of barrier performance after major disturbances in a post-institutional control environment. Such an understanding is needed to enhance stakeholder acceptance regarding the long-term efficacy of engineered barriers. This study will also support improvements in the design of evapotranspiration (ET) and hybrid (ET + capacitive) barriers and the performance monitoring systems

Lower limb stiffness estimation during running: the effect of using kinematic constraints in muscle force optimization algorithms

The focus of this paper is on the effect of muscle force optimization algorithms on the human lower limb stiffness estimation. By using a forward dynamic neuromusculoskeletal model coupled with a muscle short-range stiffness model we computed the human joint stiffness of the lower limb during running. The joint stiffness values are calculated using two different muscle force optimization procedures, namely: Toque-based and Torque/Kinematic-based algorithm. A comparison between the processed EMG signal and the corresponding estimated muscle forces with the two optimization algorithms is provided. We found that the two stiffness estimates are strongly influenced by the adopted algorithm. We observed different magnitude and timing of both the estimated muscle forces and joint stiffness time profile with respect to each gait phase, as function of the optimization algorithm used

200-BP-1 Prototype Hanford Barrier - 15 Years of Performance Monitoring

Engineered surface barriers are recognized as a remedial alternative to the removal, treatment and disposal of near-surface contaminants at a variety of waste sites within the DOE complex. One issue impacting their acceptance by stakeholders the use of limited data to predict long-term performance. In 1994, a 2-ha multi-component barrier was constructed over an existing waste disposal site at Hanford using natural materials. Monitoring has been almost continuous for the last 15 yrs and has focused on barrier stability, vegetative cover, plant and animal intrusion, and the components of the water balance, including precipitation, runoff, storage, drainage, and percolation. The total precipitation received from October 1994 through August 2008 was 3311 mm on the northern half (formerly irrigated), and 2638 mm on the southern, non-irrigated half. Water storage in the fine-soil layer shows a cyclic pattern, increasing in the winter and decreasing in the spring and summer to a lower limit of around 100 mm, regardless of precipitation, in response to evapotranspiration. Topographic surveys show the barrier and side slopes to be stable and the pea-gravel admix has proven effective in minimizing erosion through the creation of a desert pavement during deflationary periods. Three runoff events have been observed but the 600-mm design storage capacity has never been exceeded. Total percolation ranged from near zero amounts under the soil-covered plots to over 600 mm under the side slopes. The asphaltic concrete prevented any of this water from reaching the buried waste thereby eliminating the driving force for the contaminant remobilization. Plant surveys show a relatively high coverage of native plants still persists after the initial revegetation although the number of species decreased from 35 in 1994 to 10 in 2009. Ample evidence of insect and small mammal use suggests that the barrier is behaving like a recovering ecosystem. In September 2008, the north half of the barrier was burned to remove vegetation and study the effects of fire on barrier performance. The most immediate effects has been on water storage patterns with the bare surface showing a slower accumulation of water, a smaller peak storage and a delayed release relative to the unburned side due to evaporation . Nonetheless the residual storage at the end of the year was similar for the burned and unburned sides

Vadose Zone Transport Field Study: Status Report

Studies were initiated at the Hanford Site to evaluate the process controlling the transport of fluids in the vadose zone and to develop a reliable database upon which vadose-zone transport models can be calibrated. These models are needed to evaluate contaminant migration through the vadose zone to underlying groundwaters at Hanford. A study site that had previously been extensively characterized using geophysical monitoring techniques was selected in the 200 E Area. Techniques used previously included neutron probe for water content, spectral gamma logging for radionuclide tracers, and gamma scattering for wet bulk density. Building on the characterization efforts of the past 20 years, the site was instrumented to facilitate the comparison of nine vadose-zone characterization methods: advanced tensiometers, neutron probe, electrical resistance tomography (ERT), high-resolution resistivity (HRR), electromagnetic induction imaging (EMI), cross-borehole radar, and cross-borehole seismic

Managing Opportunities and Challenges of Co-Authorship

Research with the largest impact on practice and science is often conducted by teams with diverse substantive, clinical, and methodological expertise. Team and interdisciplinary research has created authorship groups with varied expertise and expectations. Co-authorship among team members presents many opportunities and challenges. Intentional planning, clear expectations, sensitivity to differing disciplinary perspectives, attention to power differentials, effective communication, timelines, attention to published guidelines, and documentation of progress will contribute to successful co-authorship. Both novice and seasoned authors will find the strategies identified by the Western Journal of Nursing Research Editorial Board useful for building positive co-authorship experiences

Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zone at Hanford

This research project addressed the effect of clastic dikes on contaminant transport in the vadose zone. Clastic dikes are vertically oriented subsurface heterogeneities that are common at the Hanford Site, including in the subsurface sediments below the tank farms in the 200 West Area. Previous studies have suggested that clastic dikes may provide a fast path for transport of leaking fluid from the tanks through the vadose zone because they cut through the horizontally layered sediments at the site. The research tested the hypothesis that clastic dikes at the Hanford Site provide preferential pathways that enhance the vertical movement of moisture and contaminants through the vadose zone. Current flow and transport models of the vadose zone at the 200 Areas are based on relatively simple hydrogeologic models that assume horizontally layered sediments with no preferential vertical flow paths. To address those scientific needs, our research included field and modeling studies of the large-scale spatial distribution of clastic dikes, the hydrologic properties within dikes, and the potential effect of clastic dikes on fluid flow through the vadose zone. The data and models of the clastic dike networks produced for this project should be directly applicable to fate and transport studies conducted at the Hanford tank farms

Psychological heterogeneity among honors college students

Greater knowledge of the psychology of honors college students will help to inform program administrators, counselors, residence life assistants, and faculty about how they may provide support to those with the greatest need. Via an online survey, personality, perfectionism, and suicidal ideation data were collected from honors college students (N = 410, 73% female). Using latent profile analysis, students were classified by their responses to the Big Five Inventory personality measure into five profiles. Risk factors of high perfectionism and suicidal ideation scores were found in two of the profiles, suggesting students with these personality characteristics may need enhanced psychological support. The largest profile (35% of students) had extraversion scores above the norm, but all other profiles had introverted scores below the norm. Neuroticism scores were also higher than the norm in the introverted profiles, which represented a majority of the honors college students