Indicators Of Reservoir Performance,
2015
Singapore University of Technology and Design
Indicators Of Reservoir Performance, Stefano Galelli
All ECSTATIC Materials
No abstract provided.
Flowability And Density Characteristics Of Controlled Low Strength Material (Clsm) Using Native High Plasticity Clay,
2015
University of Texas at Arlington
Flowability And Density Characteristics Of Controlled Low Strength Material (Clsm) Using Native High Plasticity Clay, Anand J. Puppala, Bhaskar Chittoori, Anil Raavi
Civil Engineering Faculty Publications and Presentations
In pipeline construction projects when high plastic clayey soils are encountered in the excavated trench material, they are typically landfilled and better quality materials are imported from outside quarry sources for use as bedding and haunch zone materials. This practice has detrimental environmental and cost impacts; therefore, an efficient reutilization of this high plastic excavated material to produce controlled low strength materials (CLSMs) to use as bedding and haunch zone materials will have major sustainability benefits. As a part of an on-going research study, novel CLSM mix designs were developed by utilizing native high plastic clayey soils from the excavated …
National Science Foundation Soil-Bentonite Cutoff Wall Award Abstract,
2015
Bucknell University
National Science Foundation Soil-Bentonite Cutoff Wall Award Abstract, Jeffrey C. Evans, Michael A. Malusis, Robert W. Jacob
NSF Soil-Bentonite Slurry Trench Cutoff Wall Documents
This award abstract describes the purpose of constructing a soil-bentonite cutoff wall as well as the tests that were performed to analyze the performance of the wall.
Stethoscope-Based Detection Of Detorqued Bolts Using Impact-Induced Acoustic Emissions,
2015
Boise State University
Stethoscope-Based Detection Of Detorqued Bolts Using Impact-Induced Acoustic Emissions, Joe Guarino, Robert Hamilton
Mechanical and Biomedical Engineering Faculty Publications and Presentations
Results of a preliminary study investigating a simple method for detecting looseness in bolted fasteners of a steel structure are presented. Extensive research by many investigators demonstrates that the frequency response of a bolted structural member changes when one or more bolts are loosened. A simple and effective method for detecting looseness can be applied to bolted joints, using inexpensive and commonly-available equipment and software. The difference between spectrograms associated with tight and loose bolts is clearly apparent due to the presence of a tell-tale mode when one or more bolts are loosened. Further, a striking difference can be elucidated …
Spatial Time-Dependent Reliability Analysis Of Reinforced Concrete Slab Bridges Subject To Realistic Traffic Loading,
2015
University College Dublin
Spatial Time-Dependent Reliability Analysis Of Reinforced Concrete Slab Bridges Subject To Realistic Traffic Loading, Donya Hajializadeh, Mark Stewart, Bernard Enright, Eugene J. Obrien
Articles
Resistance and loads are often correlated in time and space. The paper assesses the influence of these correlations on structural reliability/probability of failure for a typical two-lane RC slab bridge under realistic traffic loading. Spatial variables for structural resistance are cover and concrete compressive strength, which in turn affect the strength and chloride-induced corrosion of RC elements. Random variables include pit depth and model error. Correlation of weights between trucks in adjacent lanes and inter-vehicle gaps are also included and are calibrated against Weigh-In-Motion (WIM) data. Reliability analysis of deteriorating bridges needs to incorporate uncertainties associated with parameters governing the …
Identifying And Modelling Permit Trucks For Bridge Loading,
2015
Technological University Dublin
Identifying And Modelling Permit Trucks For Bridge Loading, Bernard Enright, Eugene J. Obrien, Cathal Leahy
Articles
Accurate estimates of characteristic traffic load effects are essential in order to optimize bridge safety assessment. Permit trucks dominate the extreme upper tail of the truck loading distribution and as a result need careful examination. This paper proposes rules for filtering these trucks from Weigh-In-Motion data for both the US and Europe. The importance of these trucks in critical bridge loading events is then examined for both regions. A Monte Carlo traffic simulation model is developed which focuses on the accurate simulation of permit trucks.
Hybrid Jacketing For Rapid Repair Of Seismically Damaged Reinforced Concrete Columns,
2015
Missouri University of Science and Technology
Hybrid Jacketing For Rapid Repair Of Seismically Damaged Reinforced Concrete Columns, Mostafa Fakharifar, Genda Chen, Mahdi Arezoumandi, Mohamed Elgawady
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
This study proposes hybrid jacketing for rapid repair of seismically damaged concrete columns for bridge safety. The hybrid jacketing for a reinforced concrete (RC) column is composed of a thin cold-formed steel sheet wrapped around the column and its outside prestressing strands. Although the prestressing strands can prevent buckling of the confining steel sheet, the steel sheet can in turn prevent the prestressing strands from cutting into the concrete. The hybrid jacketing concept was validated with testing of a large-scale RC column with lap splice deficiency typical of pre-1970 bridge constructions in the Central United States. Results from the original …
Performance Evaluations Of Pavement Working Platforms Constructed With Large-Sized Unconventional Aggregates,
2015
University of Illinois at Urbana-Champaign
Performance Evaluations Of Pavement Working Platforms Constructed With Large-Sized Unconventional Aggregates, Hasan Kazmee, Erol Tutumluer, Debakanta Mishra
Civil Engineering Faculty Publications and Presentations
With recent focus on sustainable construction practices and the ever-increasing transportation cost and scarcity of natural resources, use of unconventional aggregate materials, such as primary crusher run and concrete demolition waste, have become viable for the construction of pavement working platforms over very weak and often wet subgrade soils. To this end, a research study was undertaken at the Illinois Center for Transportation to evaluate the adequacy and field performances of such large-sized aggregate materials and validate new material specifications. A state-of-the-art image analysis technique was utilized to characterize the size and morphological properties, e.g. shape, texture and angularity of …
Structural Properties Of Concrete Materials Containing Roadcem,
2015
Technological University Dublin
Structural Properties Of Concrete Materials Containing Roadcem, Niall Holmes
Articles
This paper presents findings from a preliminary study to assess the structural and material properties of a nonstandard, concrete type mix containing RoadCem, a traditional soil stabilising additive. Two different mixes determined the effect of adding RoadCem in terms of compressive and flexural strengths, breaking strain, thermal expansion and contraction behaviour, permeability using a falling head, and Young’s modulus. RoadCem is a fine powder containing alkali metals and synthetic zeolites which are complemented with a complex activator. RoadCem modifies the dynamics and chemistry of cement hydration by enhancing the crystallisation process and forming longer needle crystalline structures. It reduces the …
A Review Of Probabilistic Methods Of Assessment Of Load Effects In Bridges,
2015
University College Dublin
A Review Of Probabilistic Methods Of Assessment Of Load Effects In Bridges, Eugene J. Obrien, F Schmidt, Donya Hajializadeh, X-Y Zhou, Bernard Enright, Colin C. Caprani, Simon Wilson, Emma Sheils
Articles
This paper reviews a range of statistical approaches to illustrate the influence of data quality and quantity on the probabilistic modelling of traffic load effects. It also aims to demonstrate the importance of long-run simulations in calculating characteristic traffic load effects. The popular methods of Peaks Over Threshold and Generalized Extreme Value are considered but also other methods including the Box-Cox approach, fitting to a Normal distribution and the Rice formula. For these five methods, curves are fitted to the tails of the daily maximum data. Bayesian Updating and Predictive Likelihood are also assessed, which require the entire data for …
Experimental Heat Transfer Study On Green Roofs In A Semiarid Climate During Summer,
2015
West Texas A & M University
Experimental Heat Transfer Study On Green Roofs In A Semiarid Climate During Summer, Roy Issa, Kenneth Leitch, Byungik Chang
Civil Engineering Faculty Publications
An experimental study was conducted on green roofs under the semiarid summer climatic conditions of West Texas to investigate the effect of soil type, moisture content, and the presence of a top soil grass layer on the conductive heat transfer through the roof. Two soil types were investigated: uniform sand and local silt clay. Tests were also conducted on a control roof. A dual-needle heat-pulse sensor was used to conduct thermal property tests on the soils. The tests reveal that unlike sand, the thermal conductivity of silt clay did not increase continuously with soil moisture. Better heat transfer conditions were …
Enhanced Electrokinetic Transport Of Sulfate In Saline Soil,
2015
Ecophile Co. Ltd, Seoul
Enhanced Electrokinetic Transport Of Sulfate In Saline Soil, Sung-Ung Jo, Yeon-Jun Shin, Jung-Seok Yang, Deok-Hyun Moon, Agamemnon Koutsospyros, Ki-Tae Baek
Civil Engineering Faculty Publications
The electrokinetic transport of sulfate was investigated as a means of treating and restoring a sulfate-accumulating saline soil. The electrokinetic treatment decreased the electrical conductivity of the soil, an indicator of soil salinity, to 58.6%, 73.1%, and 83.5% for 7, 14 and 21 days, respectively. More than 96% of the chloride and nitrate were removed within 7 days. However, the removal of sulfate was highly influenced by the anode material. An iron anode removed sulfate effectively, whereas, sulfate was hyper-accumulated in the anodic region when an inert anode was used. The iron anode was oxidized in a sacrificial anodic reaction, …
Reflections On Interdisciplinary Sustainability Research With Undergraduate Students,
2015
University of New Haven
Reflections On Interdisciplinary Sustainability Research With Undergraduate Students, Can B. Aktas
Civil Engineering Faculty Publications
Purpose – The purpose of the article was to convey experiences with pioneering interdisciplinary sustainability research by involving undergraduate students. Experiences with initiating and conducting multiple research projects spanning engineering and sustainability are described, and recommendations for programs and faculty in other institutions of higher education that plan to implement or support similar endeavors are discussed. Design/methodology/approach – The article and presented conclusions are based on three separate research projects, where specific examples as to how those projects were developed as well as challenges and rewards faced during the project are described. Findings – It is concluded that faculty should …
Benefit-Cost Analysis Of Using Class F Fly Ash-Based Green Cement In Masonry Units,
2015
Wayne State University
Benefit-Cost Analysis Of Using Class F Fly Ash-Based Green Cement In Masonry Units, Khaled Shwekat
Wayne State University Dissertations
ABSTRACT
BENEFIT-COST ANALYSIS OF USING CLASS F FLY ASH-BASED GREEN CEMENT IN MASONRY UNITS
by
KHALED SHWEKAT
August 2015
Advisor: Dr. Hwai-Chung Wu
Major: Civil engineering
Degree: Doctor of Philosophy
The Portland cement concrete is the most popularly used building material around the world. However, there are major drawbacks associated with Portland cement, such as the emission of greenhouse gasses and high-energy consumption from cement production. Therefore, Portland cement concrete has many disadvantages that can only be overcome by being replaced with new materials such as fly ash-based green cement. Recycling fly ash and using it to replace cement has …
Analysis Of Queue Characteristics At Signalized Intersections Near Highway-Railroad Grade Crossing,
2015
Wayne State University
Analysis Of Queue Characteristics At Signalized Intersections Near Highway-Railroad Grade Crossing, Amna Chaudhry
Wayne State University Dissertations
Analysis of traffic queues at signalized intersections which are in close proximity to highway- railroad grade crossings is of primary importance for determining if the normal signal operation needs to be preempted for railroad operations by providing a special signal mode for safe clearance of the queued vehicles from the tracks before the train arrival, and prohibiting any conflicting traffic movements towards the crossing. Such queuing analysis becomes even more critical where direct observations of traffic queues are not possible or where the assessment is needed for a future location. Inadequate estimation of queues from signalized intersections to the nearby …
Attachment Of A Combination Bridge Rail To Concrete Parapet Utilizing Epoxy Adhesive Anchors,
2015
University of Nebraska - Lincoln
Attachment Of A Combination Bridge Rail To Concrete Parapet Utilizing Epoxy Adhesive Anchors, Robert W. Bielenberg, John D. Reid, Scott K. Rosenbaugh, Austin J. Haase, Ronald K. Faller
Mid-America Transportation Center: Final Reports and Technical Briefs
The Iowa Department of Transportation (IaDOT) was interested in investigating the use of epoxy adhesive anchorages
for the attachment of posts used in the BR27C combination bridge rail system. Alternative anchorage concepts were developed using a modified version of the ACI 318-11 procedures for embedded anchor design. Four design concepts were developed for review by IaDOT, including: (1) a four-bolt square anchorage, (2) a four-bolt spread anchorage, (3) a two- bolt centered anchorage, and (4) a two-bolt offset anchorage. IaDOT representatives selected the four-bolt spread anchorage and the two-bolt offset anchorage as the preferred designs for evaluation. In addition to …
Feasibility Studies To Support Landfill Gas Recovery In Ghana,
2015
University of Texas at Arlington
Feasibility Studies To Support Landfill Gas Recovery In Ghana, Neda Jangikhatoonabad
Civil Engineering Theses - Archive
According to World Bank Ghana generates 0.09 kg of solid waste per person per day, where there are only 4 engineered landfills in the country. In 2010, Ghana contributed to 0.13% of global greenhouse gases emissions, 10% of which was associated with waste sector. On the other hand, according to the World Bank in 2011, 39.5 % of Ghana’s population did not have access to electricity. Tapping landfill gas will not only provide portion of needed energy for the country, but will also help solve many of the environmental problems. Currently there is no landfill gas to energy project in …
Using Lean Techniques To Reduce Waste And Improve Performance In Municipal Project Delivery,
2015
University of Texas at Arlington
Using Lean Techniques To Reduce Waste And Improve Performance In Municipal Project Delivery, Yasir E. Abdelrazig
Civil Engineering Theses - Archive
The basic concepts of lean thinking in construction projects are to reduce waste, improve communication, and promote teamwork integration through a common set of tools and techniques. With increased demand for public works projects, there is a need to focus attention on the efficient delivery of construction project services in the public sector, and in particular, on municipal project delivery. Performance improvements using lean techniques are considered to overcome problems, facilitate project progress, and offer recommendations for better municipal construction project processes. Municipal projects are a part of the public works which include a broad category of infrastructure projects, financed …
A Parametric Study Of The Effects Of Ɛ And ��̅ On The Poisson Boltzmann Equation For One And Two Spherical Particles Using A Boundary Integral Equation Method,
2015
University of Texas at Arlington
A Parametric Study Of The Effects Of Ɛ And ��̅ On The Poisson Boltzmann Equation For One And Two Spherical Particles Using A Boundary Integral Equation Method, Oumama H. Lingamfelter
Civil Engineering Theses - Archive
Many biomolecules, such as DNA, exhibit properties that are dependent on their electrostatic interaction with an electrolytic solution. Both explicit atomistic and implicit continuum models have been developed to solve the electrostatic problem. The implicit models are based on the Poisson-Boltzmann (PB) equation, whose lower computational cost makes them favored for bio-molecular applications, particularly as the molecule size increases. Among the implicit models, a boundary integral equation (BIE) method involving only numerical treatment on a surface in turn is more efficient than domain-based finite element and finite difference methods. This is especially so in the present case where the electric …
Comparison Of Post-Tensioned Cast In Place Concrete And Steel-Concrete Composite Bent Caps,
2015
University of Texas at Arlington
Comparison Of Post-Tensioned Cast In Place Concrete And Steel-Concrete Composite Bent Caps, Francisco David Berrocal Ruiz
Civil Engineering Theses - Archive
Civil engineering projects are conditioned not only by the technology available but also by resources availability as well as budget and construction time. Special conditions applicable to particular projects can also control their development.The correct selection from the different feasible alternatives can determine the final output of a project. In that sense, the importance of bridge structures on both the overall budget and schedule of civil engineering projects makes the selection of the proper structural typology decisive for their success or failure. In some cases, special characteristics can establish the need of innovative solutions to guarantee a successful development of …
