Geotechnical Engineering Commons^™

The Stability Of Nanobubbles And Its Application In Contaminated Sediment Treatment, Shaini Dilsha Aluthgun Hewage

Dissertations

This dissertation consists of two sections. First, nanobubbles' stability and behavior are studied using experimental and theoretical approaches. Second, nanobubbles application combined with ultrasound to remediate contaminated sediments is discussed.

The stability study consists of four sections. (i). Laboratory investigation to determine bubble size distributions and zeta potentials for different gases, pH levels, temperatures, and salt conditions. (ii). A theoretical study based on the diffused double layer theory to explain nanobubbles' behavior in different NaCl concentrations. (iii). Nanobubbles' stability in electrolyte solutions under different ion valencies using deionized water, NaCl, Na₂SO₄, Na₃PO₄, …

Assessment Of The Performance Of Grinding Circuit For Buzwagi Gold Mine, Alphonce Wikedzi

Tanzania Journal of Engineering and Technology (TJET)

It had been reported by the management of Buzwagi Gold Mine (BGM) that grinding circuit was designed to produce final product size of 125 μm, which had not been achieved for a long period of time under both, low to normal (i.e. 450-600 t/h) and high (i.e. > 650 t/h) throughputs. Also, the performance behaviour of the circuit had not been reviewed after long time of operation. Hence, an evaluation study was conducted in order to recommend improvement in mine operations. The study was realized through three circuit survey campaigns and laboratory experimentations. From the surveys, size distributions and solids contents …

Feasibility Of Geothermal Energy Piles In New Orleans Alluvial Soils, Patrick A. Thurmond

LSU New Orleans Theses and Dissertations

Geothermal energy piles offer the benefits of modifying existing construction practices to reduce costs associated with heating and cooling. A major obstacle today in effective utilization of these systems is a general lack of site-specific data on the thermal properties of subsoils. To maximize the potential efficiency of these systems, engineers require an understanding of the potential impact of this technology on existing foundation design methodology as well as a means for quantifying potential heat transfer through soil by determination of the soil’s thermal conductivity. This study examines the feasibility of energy piles with a focus on alluvial soils found …

Сharacteristics Mineral Resource Base Of Madagascar, A. E. Vorobyev, K. A. Vorobyov, S.A. Ndriambanuna, L.E. Schesnyak

Gorniy vestnik Uzbekistana

The main characteristics of the mineral resource base of Madagascar with details of coal, iron ore, non-ferrous metals, uranium, rare metals and gold are considered. In the gold-ore mineral base of Madagascar, coastal placers are of particular potential interest. Foreign mining companies and local crafts are described. The transition to the development of coastal gold placers is proposed

Laboratory Testing And Mechanistic Analysis Of Treated Subgrade Soils, Hari Kumar Reddy Yarrapureddi

Civil Engineering Theses

Calcium-based stabilizing agents such as cement and lime have been extensively used to improve the engineering properties of base and subgrade layers of pavement systems. Recently, polymers and chemical stabilizers have become popular due to cost efficiency, ease of application, and fast curing times. In this study, California Bearing Ratio (CBR) values of polymer and chemical treated soils were compared with the CBR values of soils treated with conventional stabilizers. Parametric sensitivity analyses was carried out on key parameters including the type of subgrade soil, stabilizing agent, stabilizing agent treatment levels, and moisture conditioning. Additionally, numerical analyses was performed to …

Expanding The Concept Of Comprehensive Area Ratio Parameter To The South-Central States Towards Simplifying The Structural Evaluation Of Flexible Pavements At The Network Level, Nitish R. Bastola

Civil Engineering Theses

The surface deflection bowl data collected through Non-Destructive Testing (NDT) has been widely utilized by various Department of Transportation (DOTs) in the South-Central States and other places. The primary purpose of using deflection-based NDTs in network-level assessment is to identify a weak pavement section that requires further analysis at the project level. The falling weight deflectometer (FWD) test is one of the common NDT based tests utilized by highway agencies in assessing the performance of the flexible pavement. However, a robust method to evaluate pavement sections utilizing FWD data from all the sensors are seldom developed. There is always a …

Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt

Dissertations and Theses

Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …

Cement Stabilized Crushed Stone Base Course Strength And Stiffness Analysis, Andrew Deschenes

Graduate Theses and Dissertations

Approximately 70 – 80% of state departments of transportations (DOTs) utilize the 1993 AASTHO Guide for Design of Pavement Structures (1993 AASHTO) [1] for structural design of pavements. A growing portion of DOT’s are beginning to implement the Mechanistic-Empirical Pavement Design Guide (MEPDG), referred to as AASHTOWare Pavement ME [2]. The 1993 AASHTO flexible guide applies empirically derived unitless strength values referred to as structural layer coefficients and structural numbers (SN) to pavement thickness and pavement types. The 1993 AASHTO rigid flexible guide utilizes the depth and strength of the concrete pavement, with the composite spring constant (kc), which is …

Effect Of Citric Acid On Slump, Compressive Strength, And Setting Time Of Belitic Calcium Sulfoaluminate Concrete, Israel Aguilar Rosero

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate (BCSA) cement has well established advantages related to fast setting time, fast strength gain, long-term strengths, shrinkage, and sustainability. Due to its fast setting and hardening, this type of cement has historically been used to repair concrete structures, highways, and runways. This work provides much needed guidance on establishing mix design criteria for BCSA cement. Guidance is also given on the effects of set retarders on strength, slump, and setting times. Citric acid and a phosphonic acid-based admixture were tested as retarders for different concrete mixtures. Three studies were performed. In the slump study five different water …

Incorporating Shear Resistance Into Debris Flow Triggering Model Statistics, Noah J. Lyman

Master's Theses

Several regions of the Western United States utilize statistical binary classification models to predict and manage debris flow initiation probability after wildfires. As the occurrence of wildfires and large intensity rainfall events increase, so has the frequency in which development occurs in the steep and mountainous terrain where these events arise. This resulting intersection brings with it an increasing need to derive improved results from existing models, or develop new models, to reduce the economic and human impacts that debris flows may bring. Any development or change to these models could also theoretically increase the ease of collection, processing, and …

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 …

Engineering Characteristics Of Nest Building Geomaterials Used By Mud Dauber Species, Noura Saleh

LSU Master's Theses

Mud dauber wasps construct their nests using soil from adjacent areas. Mud dauber nests have been studied from an entomological perspective. However; the properties of the nest material remain unexplored from a soil engineering perspective. This study investigated the physical and mechanical properties of the nest soil for use in future bio-inspired design to improve soil behavior as a construction material. To achieve this goal, nests from three mud dauber species (black and yellow, organ pipe, and steel blue) were collected from locations near Baton Rouge, Louisiana. The shape, weight, moisture content, organic content, and specific gravity of the nests …

The Use Of Green Pond Conglomerate As Building Stone In Morris County, New Jersey, Gregory A. Pope

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Green Pond Conglomerate (GPC) is a maroon colored quartzite with white quartz pebbles, a classic “puddingstone”. GPC derives from a NW-SW-trending sliver of Paleozoic sediments, the “Green Pond Outlier”, surrounded by older metamorphic and igneous rocks of Morris and Passaic Counties. Buildings, retaining walls, field fences, and monuments incorporate the durable and attractive stone, in a distinct geographic area of Morris County. Several instances of structures completely constructed or faced with GPC occur in and around Morristown, limited to affluent houses and one prominent church. In these cases, GPC stones were dressed and faced, a labor-intensive effort. Elsewhere in the …

Analysis Of Semi-Arid Riparian Environments Using Satellite Imagery, Kira Overin

Graduate Theses & Non-Theses

Semi-arid riparian environments are at risk of being over-exploited or degraded due to increased water usage associated with growing housing demands. Trends surrounding these developments can be monitored using freely available Landsat satellite imagery in conjunction with seasonal stream discharge rates. This project focuses on a stream system located southwest of Ennis, Montana, where population is growing rapidly. It aims to characterize the connection between variable discharge rates in small-scale riparian environments and adjoining vegetation health, while considering possible implications of continued urbanization. Methods for preventing riparian ecosystem degradation and promoting resilience are also discussed.

Factors Affecting Brittleness Behavior Of Coal-Gangue Ceramsite Lightweight Aggregate Concrete, Yunsen Wang, Jingping Qiu, Wen Deng, Jun Xing, Jian Liang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Coal gangue, which is the solid waste produced during the coal processing, causes serious environmental problems. Lightweight concrete by making use of the coal-gangue ceramsite as the aggregate has many advantages as the construction material. However, the high brittleness of lightweight aggregate concrete is one of the problems for its application in building infrastructure. In this paper, the variation regularity, influencing factors and reinforcing/toughening method were studied as the reference data for future practical applications of coal-gangue ceramsite lightweight aggregate concrete (CGCLWAC). The results show that the brittleness of CGCLWAC increases with age, but the rate of the increase of …

Improvement Of Stock Opening Diagram Of Uranium Deposits When Involving In Processing By Method Underground Leaching, Alikulov Sh.Sh., Akhadov Kh.R., Xalimov L.U.

Gorniy vestnik Uzbekistana

Uranium deposits of the Kyzylkum region, related to deposits of reservoir-infiltration or “sandstone” type and developed by the PV method, are formed mainly due to the occurrence of exogenous-epigenic processes in permeable rocks of the sedimentary cover. Research in practice shows that between the exploration characteristics often changes in the geometry of the ore body in the absence of confirmation of linear reserves. Therefore, use the present methodology to clarify the random errors of the parameters between exploration and industrial, to extract products from the bowels as much as possible and without loss. After clarification and justification of all necessary …

Extraction Purification Of Concentrates Of Rare Earth Elements From Impurities And Natural Radionuclides, O.F. Petuhov, B.T. Ruziev, U.Z. Sharafutdinov

Gorniy vestnik Uzbekistana

The article presents the results of experimental studies on the extraction of rare-earth element concentrates from impurities and natural radionuclides. As part of the research, a technology for cleaning concentrates has been developed, including the following operations: Experimental studies have shown the possibility of effective purification of rare-earth element concentrates from impurities and natural radionuclides by the extraction method.

Hybrid Passive Control System For Seismic Response Mitigation Of Steel Frame Structures, Mohammad Hossein Mehrabi

Student Works (2020-2029)

Large vibration forces such as from seismic excitations can cause structural damage and structural collapse in the case of intense earthquakes. A large number of novel methods and of these techniques has weaknesses and strengths. Several control devices demonstrate a two-step mechanism in which the structure's stiffness is initially raised, and then the of the first vibration period down to a region where the structural response is significantly increased. The main aim of this thesis is to propose a hybrid passive control system comprises of two phases for the seismic retrofit of moment-resisting steel frames. The first phase is a …

St. Mary And St. Anne Cathedral, Cork: An Optimum Heating Solution For Heritage Buildings?, Christopher Shiell, Roger P. West

Civil Engineering Research in Ireland 2020

Cathedrals and most churches are characterised by having large internal, undivided spaces and permeable building envelopes. They are often used little, intermittently, but predictably and, in spite of the fact that they are unique in still being largely used for the purpose for which they were built many centuries ago, they are now often used for additional purposes, for which they were never designed. These uses include concerts, graduation ceremonies, filming and a host of other uses all of which require a level of thermal comfort not envisaged by the original builders. Research was undertaken by the authors into the …

Challenges And Opportunities To Deep Retrofitting Of Traditional Fabric Buildings To Achieve Nearly Zero Energy Building (Nzeb), Maria Lopez Zambrano, Paul Kenny, Jamie Goggins

Civil Engineering Research in Ireland 2020

Many of our traditional buildings are disappearing or in danger of being under utilised because they are not comfortable for modern day living and do not meet our present day needs. If a building does not have a use, inevitably it deteriorates and eventually becomes a ruin or gets demolished. It is important to retrofit these buildings, which are part of our identity and can be powerful tourist attractions even though most of them are not listed. Some owners want to apply for retrofitting schemes and grants, but they are rejected because there are no standard solutions to achieve low …

Can Deap Help Us To Predict The Energy Demand And Indoor Temperature Of Homes Before And After Renovation? A Case Study From Dublin, Paul Moran, Jamie Goggins

Civil Engineering Research in Ireland 2020

Improving the energy efficiency of buildings via retrofitting is seen as one of the key mitigation measures to reducing the energy demand and carbon emissions of the built environment in Ireland. However, while energy efficiency retrofits for buildings are effective in theory, the energy savings estimated by statistical or engineering models can often be inaccurate. The Domestic Energy Assessment Procedure (DEAP) is the standard assessment procedure used for assessing the energy performance standard of residential buildings in Ireland. This paper examines the gas energy demand for space and water heating and the internal temperature profiles in contrast to DEAP estimates …

Operational And Embodied Energy Analysis Of 8 Single-Occupant Dwellings Retrofit To Nzeb Standard, Richard O'Hegarty, Shane Colclough, Oliver Kinnane, Donal Lennon, Etienne Rieux

Civil Engineering Research in Ireland 2020

In line with the Energy Performance of Buildings Directive, Irish dwellings are being retrofit to near Zero Energy Building (nZEB) standards - with a number of the deep energy retrofits classified as A-rated. As a result of the low operational energy, the embodied energy share of an nZEB's life cycle energy is significantly increased. Therefore, to obtain a holistic picture of the change in energy profile of buildings, the embodied energy of the material added to achieve that low performance should also be taken into account. This paper presents results from a case study of 8 single-occupant terrace bungalows retrofit …

The Broader Development Of The Student Engineer Through Industry Based Experiential Learning, Donogh Coleman, Ted Mckenna, Mary Moloney

Civil Engineering Research in Ireland 2020

The global drive for industry-aware and industry-ready engineering graduates, has led to the development and integration of experiential learning through work placements. Industry is looking to recruit graduates with not just the requisite technical engineering skills, but also graduates with inter alia high levels of teamwork and communications skills. This has been recognised by CIT with the integration of work placement in most of its undergraduate programmes. This paper provides an overview of the student placement process in the Department of Civil, Structural and Environmental Engineering at CIT, includes the work placement alternative which was implemented due to the COVID-19 …

Art In Engineering: Evoking A Creative Response From Engineering Students And More, Jamie Goggins, Marta Fuente, Eamonn Madden

Civil Engineering Research in Ireland 2020

The concept of creativity being only associated with writers, painters, and artistic professions is outdated. The future engineer must embrace maths, art and creativity to unlock innovative solutions. Traditional engineering courses with an emphasis predominately on maths and science can produce graduates who are constrained in developing design solutions without creativity to unlock innovative solutions. This paper describes a short course introduced in the School of Engineering at NUIGalway in 2018 to expose students to creative thinking research and principles and engage in various forms of creative expression (photography, painting and essay writing) to articulate their response to a set …

Teaching Of Structural Analysis Into The Future, Dermot O'Dwyer

Civil Engineering Research in Ireland 2020

The engineering curriculum has always been full. In the past civil and structural engineers studied a wide variety of technical subjects within the broad field of engineering science and spent many hours working on design projects. Modern engineering curricula try to cover these areas while also dedicating more time to structured group-work, report writing and communication skills. Although students spend longer in college the number and range of technical fields that students must master is considerably larger than in the past. As a result the time available to any one topic area has reduced. At the same time the work …

Loading On Long Span Bridges In Heavily Trafficked Areas, Michael Quilligan, Eugene O'Brien

Civil Engineering Research in Ireland 2020

The critical traffic loading condition for long-span bridges is congestion when vehicles may be closely spaced together. Data on very high traffic flows is limited however, as induction loops which are typically used to collect traffic data, are ineffective when traffic flow breaks down. A number of long span bridges are located in areas of high traffic with periods of recurring congestion occurring daily. While the inter-vehicle gap distances are greater than those occurring during non-recurring full stop accident type events, the high frequency of the recurring congestion events can increase the probability of a critical load case occurring.

A Numerical Study Of The Effect Of Wind Barriers On Traffic And The Bridge Deck, Yuxiang Zhang, Philip Cardiff, Jennifer Keenahan

Civil Engineering Research in Ireland 2020

Wind actions can have a great impact on both bridges and traffic on bridges. However, structures designed to shelter the traffic from wind can influence the aerodynamic performance of the bridge deck, especially for long-span bridges. This study compares the effect of non-perforated walls and perforated walls used as wind barriers for traffic by conducting Computational Fluid Dynamics (CFD) simulations on three-dimensional geometries of a four-lane bridge deck. Steady-state simulations employ the Reynolds-Averaged Navier Stokes (RANS) method with the k-epsilon turbulence model and all simulations use parallel computing. An open-sourced software OpenFOAM is used.

Long-Run Traffic Simulations For Multi-Lane Road Bridges, Róisín Donnelly, Lorcan Connolly, Ilaria Bernardini

Civil Engineering Research in Ireland 2020

The maintenance and repair of ageing bridges is a concern for road infrastructure managers. This issue is amplified by the increasing weights and frequency of travel of freight vehicles in recent times. In order to accurately assess the risk of damage for road bridges, it is essential to have knowledge of both historical and current bridge loading. When available, site-specific Weigh-in-Motion (WIM) data can be effective in creating representative load models for a structure. However, for cases where WIM data is not available and in cases where future damage must be predicted, it is necessary to simulate appropriate data using …

Simulation Of Traffic Loading On Long Span Bridges, Hang Zhang, Michael Quilligan

Civil Engineering Research in Ireland 2020

Existing long span load models have typically been developed using a number of conservative assumptions, and as such are more applicable to the design of new bridges rather than the assessment of existing structures. Excessive conservatism in such assumptions can lead to expensive and unnecessary interventions in existing bridges. Furthermore, existing load models do not always allow for correlations in traffic weights and vehicle positions on the bridge.

Repair & Rehabilitation Of Daly's (Shakey) Bridge, Cork City, Michael Minehane, John Gamble

Civil Engineering Research in Ireland 2020

This paper describes the rehabilitation of (Shakey) Bridge, an existing single-span suspension bridge crossing the northern channel of the River Lee in Cork City. The bridge was opened in 1927 to replace an earlier ferry crossing at the same location. Daly’s bridge is included on the Record of Protected Structures and the National Inventory of Architectural Heritage. It remains the only suspension bridge in Cork City and is the only surviving bridge of its kind in Ireland. It is considered to be a significant contributor to the architectural heritage of the city. This case study describes the project development including …