Civil Engineering Commons^™

Double Vault Composting Latrines In Rural Paraguay : Feasible Construction And Optimal Use, Paul T. Pebler

Dissertations, Master's Theses and Master's Reports - Open

Water resource depletion and sanitation are growing problems around the world. A solution to both of these problems is the use of composting latrines, as it requires no water and has been recommended by the World Health Organization as an improved sanitation technology. However, little analysis has been done on the decomposition process occurring inside the latrine, including what temperatures are reached and what variables most affect the composting process. Having better knowledge of how outside variables affect composting latrines can aid development workers on the choice of implementing such technology, and to better educate the users on the appropriate …

Timetable Management Technique In Railway Capacity Analysis: Development Of The Hybrid Optimization Of Train Schedules (Hots) Model, Hamed Pouryousef

Dissertations, Master's Theses and Master's Reports - Open

There are two general approaches to improve the capacity in a rail corridor, either by applying new capital infrastructure investment or by improving the operation of the rail services. Techniques to evaluate the railway operation include modeling and optimization through the use of commercial timetable management and rail simulation tools. However, only a few of the existing tools include complete features of timetable management techniques (e.g. timetable compression) are equipped with an optimization model for rescheduling and timetable improvement and this is especially true when it comes to the U.S. rail environment that prevalently uses unstructured operation practices.

This dissertation …

Stabilization Of Iron Mine Tailings Through Microbially Induced Calcite Precipitation, Noah D. Buikema

Dissertations, Master's Theses and Master's Reports - Open

Mine tailings are deposited into large-scale impoundments. Seasonal temperature fluctuations destabilize particles on the impoundment surface. Wind-induced shear stresses on the destabilized particles can in turn result in suspension of micron-sized particles into the atmosphere, creating dust storms that pose hazards to humans and the environment. Thus, efficient and sustainable methods of dust abatement are needed. One novel method for controlling dust emissions is biomodification. For example, Sporosarcina pasteurii can promote biocalcification in soil via ureolysis. However, application of this method to fined grained materials, such as mine tailings, is challenging. The goal of this work was to perform a …

Performance-Based Engineering For Evaluation And Retrofitting Non-Ductile Reinforced Concrete Buildings Incorporating Aftershock Hazard, Ruilong Han

Dissertations, Master's Theses and Master's Reports - Open

Performance-based engineering (PBE) provides a probabilistic tool for assessing the seismic risk and performance of buildings. Only the mainshock hazard has been included in the current PBE framework, although the concern on aftershock hazard has been increased recently. This study develops methodologies to incorporate aftershock hazard into a PBE framework, and assesses the seismic risk and performance of non-ductile reinforced concrete (RC) frame buildings under mainshock and aftershock hazards. A seismic retrofit strategy for these buildings, base isolation, is also evaluated using the developed methodologies.

A methodology for synthesizing aftershock ground motions is proposed and validated to resolve the challenge …

A Field Investigation Of Composite Mud Brick Compressive Strength, Kevin D. Hale

Dissertations, Master's Theses and Master's Reports - Open

It has been highlighted in numerous publications that in the field of earth construction there is a strong disconnect between experimental work in the laboratory and its application in the field. The current study attempts to help bridge this gap with a field test conducted in Nampula, Mozambique. Mud bricks were made with a simple hand mold and reinforced with bamboo and straw fibers. Fibers were cut into lengths of 3 cm and 6 cm while being mixed in fractions of 0.125%, 0.25% and 0.50% by weight and compressive strength was measured using an application of the 3-point bending test. …

Development Of A Fundamental Rating System For Identifying Sprawl: A Case Study Utilizing Small Cities In Michigan, Jonathan T. Riehl

Dissertations, Master's Theses and Master's Reports - Open

Urban sprawl research generally fits into one or more of four realms including definitions, causes, components, and consequences. Although research on consequences continues to thrive, research on components is in its adolescence, primarily due a lack of consensus on definition. Recent studies such as Ewing et al. 2014 have narrowed the list of sprawl metrics to about 20 within four factors including development density, land use mix, activity centering, and street accessibility.

This main product of this research is a Sprawl Scorecard for small Michigan cities varying in size from Traverse City, nearly 50,000 people in the urban cluster, down …

Numerical Study Of Structural Responses Of Rigid And Flexible Pavements Under Heavy Vehicles’ Loading, Rezwana Kabir

Dissertations, Master's Theses and Master's Reports

The highway system serves as the most critical transportation link in the economic development of a nation. In Michigan, about 74% of all the commodities delivered annually are transported by heavy trucks. The Michigan Department of Transportation (MDOT) permits multi-axle (11 axles) heavy truck with gross vehicle weight (GVW) limit of 164,000 lb., unlike many states having GVW limit of 80,000 lb. The effect of these heavy truck loadings on pavements might accelerate the rate of deterioration for flexible and rigid pavement structures. More detailed knowledge of the interaction of trucks with the pavement structure is essential for better management …

The Effect Of Water Temperature On In-Stream Sediment Concentration And Transport Rate, Jennie Tyrrell

Dissertations, Master's Theses and Master's Reports

Global climate change may result in rising temperatures. As a result, ecological health and the human use of rivers may be impacted. The hydrologic cycle, watershed hydrology, and in-stream hydraulics are dynamic systems, influenced by human activities, natural events, and climate. Although known drivers like precipitation and stream velocity govern sediment processes, the effect of water temperature on sediment transport remains unclear. In-stream sediment movement could lead to blocked harbors, flooding, and degradation of vulnerable fish habitat. To better understand how fluctuations in water temperature affect sediment dynamics, six transport models were analyzed on the Niobrara River, with water temperatures …