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- All Subjects: Transportation
- Creators: Kaloush, Kamil
leading to chronic stress, a sense of powerlessness, and decreased autonomy. Social support may improve health empowerment and lead to increased perception of well-being.
Purpose: The purpose of this project was to evaluate the effectiveness of social support provided by a cancer support agency on health empowerment and perceived well-being in adults impacted by cancer.
Conceptual Framework: The Health Empowerment Theory maintains that perceived wellbeing is the desired outcome; mediated by health empowerment through social support, personal growth, and purposeful participation in active goal attainment.
Methods: Twelve adults impacted by cancer agreed to complete online questionnaires at
baseline and at 12 weeks after beginning participation in social support programs provided by a cancer support agency.
Instruments included: Patient Empowerment Scale, The Short Warwick-Edinburgh Mental Well-Being Scale (SWEMWBS), and The Office of National Statistics (ONS) Subjective Well-Being Questions.
Results: Four participants completed pre and post surveys. An increase was seen in
empowerment scores (pre M = 1.78, SD = 0.35 and post M = 3.05, SD = 0.42). There was no
increase in perceived well-being: SWEMWBS pre (M= 3.71, SD= 0.76), post (M= 3.57, SD=
0.65); ONS pre (M= 7.69, SD= 1.36), post (M= 6.59, SD= 1.52).
Implications: The data showed an increase in health empowerment scores after utilizing social support programs, lending support to the agency’s support strategies. It is recommended that the measures be included in surveys routinely conducted by the agency to continue to assess the impact of programming on health empowerment, and perceived well-being.
Crumb rubber use in asphalt mixtures by means of wet process technology has been in place for several years in the United States with good performance record; however, it has some shortcomings such as maintaining high mixing and compaction temperatures in the field production. Organosilane (OS), a nanotechnology chemical substantially improves the bonding between aggregate and asphalt by modifying the aggregate structure from hydrophilic to hydrophobic contributing to increased moisture resistance of conventional asphalt mixtures. Use of Organosilane also reduces the mixing and compaction temperatures and facilitates similar compaction effort at lower temperatures. The objective of this research study was first to perform a Superpave mix design for Crumb Rubber Modified Binder (CRMB) gap-graded mixture with and without Organosilane; and secondly, analyse the performance of CRMB mixtures with and without Organosilane by conducting various laboratory tests. Performance Grade (PG) 64-22 binder was used to create the gap-graded Hot Mix Asphalt (HMA) mixtures for this study. Laboratory tests included rotational viscometer binder test and mixtures tests: dynamic modulus, flow number, tensile strength ratio, and C* fracture test. Results from the tests indicated that the addition of Organosilane facilitated easier compaction efforts despite reduced mixing and compaction temperatures. Organosilane also modestly increased the moisture susceptibility and resistance to crack propagation yet retaining equal rutting resistance of the CRMB mixtures.
In this research effort, a reliability framework is developed using Monte Carlo simulation for predicting the fatigue life of AC material using the S-VECD model. The reliability analysis reveals that the fatigue life prediction is very sensitive to the uncertainty in the input variables. FAM testing in similar loading conditions as AC, and upscaling of AC modulus and damage response using FAM properties from a relatively simple homogenized continuum approach shows promising results. The FAM phase fatigue life prediction and upscaling of FAM results to AC show more reliable fatigue life prediction than the fatigue life prediction of AC material using its experimental data. To assess the sensitivity of fatigue life prediction model to uncertainty in the input variables, a parametric sensitivity study is conducted on the S-VECD model. Overall, the findings from this research show promising results both in terms of upscaling FAM to AC properties and the reliability of fatigue prediction in AC using experimental data on FAM.
The objective of the research is to test the use of 3D printed thermoplastic to produce fixtures which affix instrumentation to asphalt concrete samples used for Simple Performance Testing (SPT). The testing is done as part of materials characterization to obtain properties that will help in future pavement designs. Currently, these fixtures (mounting studs) are made of expensive brass and cumbersome to clean with or without chemicals.
Three types of thermoplastics were utilized to assess the effect of temperature and applied stress on the performance of the 3D printed studs. Asphalt concrete samples fitted with thermoplastic studs were tested according to AASHTO & ASTM standards. The thermoplastics tested are: Polylactic acid (PLA), the most common 3D printing material; Acrylonitrile Butadiene Styrene (ABS), a typical 3D printing material which is less rigid than PLA and has a higher melting temperature; Polycarbonate (PC), a strong, high temperature 3D printing material.
A high traffic volume Marshal mix design from the City of Phoenix was obtained and adapted to a Superpave mix design methodology. The mix design is dense-graded with nominal maximum aggregate size of ¾” inch and a PG 70-10 binder. Samples were fabricated and the following tests were performed: Dynamic Modulus |E*| conducted at five temperatures and six frequencies; Flow Number conducted at a high temperature of 50°C, and axial cyclic fatigue test at a moderate temperature of 18°C.
The results from SPT for each 3D printed material were compared to results using brass mounting studs. Validation or rejection of the concept was determined from statistical analysis on the mean and variance of collected SPT test data.
The concept of using 3D printed thermoplastic for mounting stud fabrication is a promising option; however, the concept should be verified with more extensive research using a variety of asphalt mixes and operators to ensure no bias in the repeatability and reproducibility of test results. The Polycarbonate (PC) had a stronger layer bonding than ABS and PLA while printing. It was recommended for follow up studies.
Chloride solutions have historically been used to stabilize roads and to prevent dust; however, very little work has been done on investigating the soil stabilizing benefits from interactions between salt solutions and different soil types. The primary goal of this research was to analyze the feasibility of utilizing a salt waste product as an economically and environmentally responsible means of dust control and/or soil stabilization. Specifically, this study documents an investigation leading to the understanding of how the addition of saline based waste products, when using a soil stabilizer, modifies the strength behavior of soils.
The scope of work included the evaluation of current literature, examination of the main challenges meeting relevant governmental regulations, and exploring the possibility of using saline waste to improve roadways.
Three soils were selected, treated with varying amounts of salt (calcium chloride, CaCl2), and tests included soil composition and classification, correlation of soil characteristics and salt, and obtaining strength parameters that are typically used in pavement design and analysis. The work effort also included the determination of the optimum dosage of salt concentration for each soil. Because Lime treatment is also commonly used in soil stabilization, one of the soils in this study included a treatment with Lime for comparison purposes.
Results revealed that when salt concentration was increased, a decrease in the plasticity index was observed in all soils. A modest to considerable strength gain of the treated material was also observed for two of the soils; however, a strength loss was observed for the third soil, which was attributed to its low clay content.
When comparing the soil corrosive potential, the additional salt treatment showed promise for increasing strength, to an extent; however, it changes the chemical properties of the soil. The soils prior to treatment were corrosive, which could be managed with appropriate techniques, but the salt increases the values to levels that could be potentially cost prohibitive if salt was used by itself to treat the soil.
The pavement design and performance investigation revealed that the Vineyard soil treated at 16% CaCl2 had an improvement that is comparable to the Lime treatment. On the other hand, the Eager soil showed very little pavement performance improvement at 8% CaCl2; this goes back to the effect of acid on the clay mineralogy. It was also postulated that using salt by-products to stabilize highway shoulders could be beneficial and save a lot of maintenance money when it comes to cleaning unwanted vegetation. A salt saturated soil structure could help in dust control as well.
Future environmental challenges for salt leaching that could affect agriculture in developing countries will still need to be carefully considered. The chlorine levels in the soil would increase, and if not treated, can potentially have corrosive effects on buried structures. Future research is recommended in this area and to also evaluate soil stabilizing properties of varying proportions of Lime and salt using the approach provided in this study.