Civil and Environmental Engineering Commons^™

Environmental Geotechnics: Challenges And Opportunities In The Post-Covid-19 World, Arvin Farid

Civil Engineering Faculty Publications and Presentations

The outbreak of the coronavirus disease 2019 (Covid-19) pandemic not only has created a health crisis across the world but is also expected to impact negatively the global economy and societies at a scale that is maybe larger than that of the 2008 financial crisis. Simultaneously, it has inevitably exerted many negative consequences on the geoenvironment on which human beings depend. The current paper articulates the role of environmental geotechnics in elucidating and mitigating the effects of the current pandemic. It is the belief of all authors that the Covid-19 pandemic presents not only significant challenges but also opportunities for …

In-Situ Fluid Injections To Achieve Bio-Stimulated Calcite Precipitation In Expansive Soils, Anish Pathak

Boise State University Theses and Dissertations

Expansive soils undergo vast changes in volume when subject to change in water contents and cause damages to infrastructures across the world. Traditional methods of tackling the problem of expansive soils using cement or lime are environmentally unfriendly and expensive. Microbial Induced Calcite Precipitation (MICP) is a new method which uses bacteria in the soil to precipitate CaCO3 (calcite) and improve the engineering properties of soils. Various laboratory studies have shown that this method can be applied successfully to treat expansive soils, but the field application of the method have barely been studied.

To study the applicability of MICP in …

A Unified Risk-Based Framework For Assessing Sustainability And Resiliency Of Civil Infrastructure, Thomas Adam Robbins

Boise State University Theses and Dissertations

As of February 2019, the National Aeronautics and Space Administration (NASA) has reported since 1880 the average global temperature has increased 1°C, with the warmest year on record being 2016. As the years continue to pass, it is becoming more evident that climate change is occurring, which is known to be a catalyst for climatic weather events. Statistically speaking, these events are more prevalent, and catastrophic exemplified as hurricanes, earthquakes, flooding, and fires. In addition to the increase of potentially catastrophic events, society as a whole has become more conscientious in the use and preservation of natural resources, waste generation, …

Machine Learning Methods To Map Stabilizer Effectiveness Based On Common Soil Properties, Amit Gajurel

Boise State University Theses and Dissertations

Unconfined compressive strength (UCS) has been widely used as one of the primary criteria for the selection of optimum type and amount of chemical stabilizer for subgrade/base stabilization. Guidelines established by various state and federal agencies aid in selecting these optimum values by recommending an initial type and amount based on a wide range of soil index properties. A significant number of laboratory trials have to be done to establish the optimum type and amount of stabilizer for a given target strength. This process takes a copious amount of time, money, and the workforce. In addition to that, the finite …

Studying The Use Of Microbial Induced Calcite Precipitation As A Shallow Stabilization Alternative To Treat Expansive Soils, Tasria Rahman

Boise State University Theses and Dissertations

Expansive soils usually recognized as swell-shrink soils have been a problem for civil infrastructure for a long time. It has been a very common practice to use chemical stabilizers including cement and lime to stabilize expansive soils, especially for lightly loaded structures. However, due to the the detrimental effects of these stabilizers on the environment and several occurrences of premature failures after stabilizing with chemical additives, engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is a promising process, which can improve the properties of expansive soil through calcite precipitation. Previous research has shown promise for …

Evaluating The Effectiveness Of A Hybrid Geosynthetic Reinforcement System To Mitigate Differential Heave On Flexible Pavement Due To Expansive Subgrades, Mir Md. Tamim

Boise State University Theses and Dissertations

Transportation industries encounter substantial challenges with respect to ride quality and serviceability when they deal with expansive soils underneath roadway structures. These soils exhibit swell-shrink behavior with moisture variations, which cause surficial heaving on the pavement structure and cost billions of dollars for the maintenance of pavements. For the past four decades, a particular stretch of US-95 (Oregon line to Elephant Butte) exhibited recurrent swelling distresses due to the underlying expansive soils. Despite remedial measures that exhibited satisfactory results for most of the sections, recurrent damage still continued in few sections. Further research indicated that the problematic soils were located …

Subsurface Characterization Of Flexible Pavements Constructed Over Expansive Soil Subgrades And Selection Of Suitable Rehabilitation Alternatives, Kazi Moinul Islam

Boise State University Theses and Dissertations

Expansive soils present significant engineering challenges, with annual costs associated with repairing structures constructed over expansive soils estimated to run into several billion dollars. Volume changes in expansive soil deposits induced by fluctuations in the moisture content can result in severe damage to overlying structures. A flexible pavement section near the Western Border of Idaho has experienced recurrent damage due to volume changes in the underlying expansive soil layer; traditional stabilization methods have provided partial success over the years. The main objective of this research effort was to characterize the problematic soil layer contributing to the recurrent pavement damage and …

Effect Of Particle Size Distribution And Packing Characteristics On Railroad Ballast Shear Strength: A Numerical Study Using The Discrete Element Method, S. M. Naziur Mahmud

Boise State University Theses and Dissertations

Railroad infrastructure plays a significant role in sustaining the economy of a country, and facilitates fast, safe and reliable transportation of passengers as well as commodities. Significant capital investments are required for the construction and maintenance of a railroad network that is structurally and functionally adequate. The ballast layer is one of the main structural components of a conventional rail track system, and comprises coarse-grained unbound particles, often as large as in size. The ballast as a load-bearing layer resists train-induced stresses through particle-particle interaction. Accordingly, particle-size distribution and packing characteristics are important factors that govern the mechanical behavior of …

Evaluating The Suitability Of Microbial Induced Calcite Precipitation Technique For Stabilizing Expansive Soils, Sikha Neupane

Boise State University Theses and Dissertations

Expansive soils, also known as swell-shrink soils have been a problem for civil infrastructures including roads and foundations from ancient times. The use of chemical additives such as cement and lime to stabilize expansive soils is a common practice among geotechnical engineers especially for lightly loaded structures. However, several occurrences of subgrade failures were observed after stabilizing with chemical additives hence engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is gaining attention as an environmental friendly soil improvement technique. Several researchers have successfully tested its feasibility in mitigating liquefaction induced problems in sandy soils. This …

Coupled Numerical Analysis Of Variations In The Capacity Of An Energy Pile In Clay Soil, Daniel Patrick Zimmerman

Boise State University Theses and Dissertations

Energy piles are an emerging alternative for the reduction of energy consumption to heat and cool buildings. The majority of the research to date focuses on thermodynamic properties or axial strain of piles. This paper concerns the effects of temperature fluctuation on the capacity of driven energy piles in clayey soils. Consolidation of clay (due to the dissipation of excess pore-water pressure in clay) surrounding piles affects the capacity of the pile (pile setup in clay). Reciprocally, it is reasonable to assume that heating and cooling periods will create or relax the excess pore-water pressure (EPWP) in clayey soils (due …

Electromagnetically Induced Alteration Of Hydraulic Conductivity Of Coarse-Grained Soils For Geotechnical Applications, Rakesh Acharya

Boise State University Theses and Dissertations

Electromagnetic (EM) waves of various power levels and frequencies can be used to alter the hydraulic conductivity of soil with minimal heat generation. The result can lead to a number of potential applications such as contamination remediation and liquefaction mitigation. In this research, the possibility of radio-frequency (RF) waves’ effect on the excess pore-water pressure (EPWP) generation and hydraulic conductivity of coarse-grained soils has been investigated.

Impact tests were performed on glass beads to examine the effect on the generation of EPWP due to RF waves. These tests were performed on a rigid box made of Plexiglas. The impacts were …

Multi-Component Active Source Rayleigh Wave Analysis, Gabriel Gribler

Boise State University Theses and Dissertations

Determining how a building site will respond to earthquake ground shaking plays a critical role in proper construction practices. One critical constraint on how a site responds is the near surface shear wave seismic velocity distribution. One commonly used method for indirectly estimating shear wave velocities is Multichannel Analysis of Surface Waves (MASW), which utilizes a spread of vertical geophones to measure Rayleigh wave dispersion. With this approach, phase velocity vs. frequency dispersion curve picks can be used to estimate shear wave velocities with depth. I investigate the use of two (vertical and horizontal inline) component seismic signals to record …

Em Stimulation Of Water For Geotechnical Applications, Harlan Dwight Olson Sangrey

Boise State University Theses and Dissertations

The task of cleaning soil and/or groundwater contaminated by leakage from aging underground gasoline or petrochemical tanks along with surface spills of gasoline and other hazardous chemicals is of utmost importance for federal and state environmental agencies. Traditional clean up and contaminant removal involves dig-and-treat methods that are costly and impractical for large, contaminated sites. Less disruptive remediation techniques, such as air sparging, have become more attractive in the past decade. Air sparging, bioventing, and other remediation technologies that use air injection into soil can become very effective for non-aqueous phase liquid (NAPL) removal using volatilization and bioremediation. However, the …