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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Saline Waste Use for Subgrade Soil Improvement

January 2017 (has links)
abstract: 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. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2017
2

Impacts of Tires and Axle Configurations on Perpetual Pavement Response

Tarawneh, Derar Mohammad Hamed 24 May 2022 (has links)
No description available.
3

Evaluation of Chemically Stabilized Subgrades with High Sulfate Concentrations

Kennedy, Kalub S. 11 June 2019 (has links)
No description available.
4

Design and Construction of Pavements in Cold Regions: State of the Practice

Smith, Brad Steven 07 December 2006 (has links) (PDF)
The effects of frost action introduce many challenges in the design and construction of roadways in cold regions throughout the United States. The penetration of frost into pavement structures can lead to differential frost heave during winter and thaw weakening during spring. Both of these damage mechanisms lead to premature pavement distress, structural deterioration, and poor ride quality. Because the availability of naturally occurring non-frost-susceptible pavement base materials is rapidly diminishing in many areas while project budgets remain largely inadequate, pavement engineers are utilizing alternative materials and techniques to minimize such damage. The purpose of this research was to investigate and document the state of the practice concerning the design and construction of pavements in cold regions. In particular, the various methods and standards employed for characterizing materials, improving soils and aggregates, and determining pavement layer thicknesses were explored. A comprehensive literature review was performed, and a questionnaire survey was conducted of various state DOTs throughout the United States that are involved with the design and maintenance of roadways. The study was directed primarily at identifying practices utilized by state DOTs in climates with freezing temperatures. The information obtained in this research represents a unique compilation of standards of practice that have been developed by DOTs based on years of experience and research in their respective jurisdictions. While this research allows engineers at state DOTs to compare their pavement design and construction practices with those of other states represented in the survey, consulting engineers and engineers in local governments involved in characterizing materials, improving soils and aggregates, and determining pavement layer thicknesses can also benefit from this work.
5

Evaluación de la estabilización de subrasante de baja capacidad incorporando aditivos AggreBind y MaxxSeal 200 en vías urbanas no pavimentadas en el distrito de La Victoria, Lambayeque, 2021

Cumpa Effio, Angello Arana January 2024 (has links)
El presente estudio titulado “Evaluación de la estabilización de Subrasante de baja capacidad incorporando aditivos AggreBind y MaxxSeal 200 en vías urbanas no pavimentadas en el distrito de La Victoria, Lambayeque, 2021” tiene como fin analizar la influencia de la incorporación de los aditivos AggreBind y MaxxSeal 200 en el mejoramiento de las propiedades físico-mecánicas en la estabilización de subrasante de baja capacidad. El método que se empleó en esta tesis fue de tipo experimental, con nivel de carácter explicativo; en cuanto a la población se consideró el PJ. Antonio Raymondi del ACQUA Sector 1, ubicado en el distrito de La Victoria, se tomaron muestra de suelo por medio de calicatas para posteriores pruebas de laboratorio sin y con estabilizantes, aplicando al menos tres dosificaciones tanto para AggreBind (2, 4 y 6 lt/m3) como para MaxxSeal 200 (3, 6 y 9 lt/m2) y finalmente se procede hacer la comparación. Los resultados conseguidos evidencian que el suelo del PJ. Antonio Raymondi del ACQUA Sector 1 es una arcilla de baja a mediana plasticidad, además se determinó la dosificación óptima para AggreBind que es de 6lt/m3, obteniendo un CBR de 12.16% con una MDS de 1.91 gr/cm3, un OCH de 12.19% y para MaxxSeal 200 de 6lt/m2 con un CBR de 11.80% con una MDS de 1.89, un OCH de 12.24%. / The present study entitled "Evaluation of low-capacity subgrade stabilization incorporating AggreBind and MaxxSeal 200 additives in unpaved urban roads in the district of La Victoria, Lambayeque, 2021" aims to analyze the influence of the incorporation of AggreBind and MaxxSeal 200 additives in the improvement of the physical-mechanical properties in the stabilization of low-capacity subgrade. The method used in this thesis was of experimental type, with explanatory character level; as for the population, the PJ was considered. Antonio Raymondi of ACQUA Sector 1, located in the district of La Victoria, soil samples were taken by means of soil pits for subsequent laboratory tests without and with stabilizers, applying at least three dosages for both AggreBind (2, 4 and 6 lt/m3) and MaxxSeal 200 (3, 6 and 9 lt/m2) and finally a comparison was made. The results obtained show that the soil of the PJ. Antonio Raymondi del ACQUA Sector 1 is a clay of low to medium plasticity, in addition, the optimum dosage for AggreBind was determined to be 6lt/m3, obtaining a CBR of 12.16% with an MDS of 1.91 gr/cm3, an OCH of 12.19% and for MaxxSeal 200 of 6lt/m2 with a CBR of 11.80% with an MDS of 1.89, an OCH of 12.24%.
6

Incorporating Chemical Stabilization of the Subgrade in Pavement Design andConstruction Practices

Al-Jhayyish, Anwer K. 22 September 2014 (has links)
No description available.

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