Civil Engineering Commons^™

Statistical Model For Estimating Carbon Dioxide Emissions From A Light-Duty Gasoline Vehicle, Benjamin Nmai Afotey, Melanie L. Sattler, Stephen P. Mattingly, Victoria Chen

Civil Engineering Faculty Publications - Archive

No abstract provided.

Effect Of Differential Movement Of Straight Reinforcing Bars During Early Age Curing On The Bond Strength, Tyler Andrews

All Theses

As the nation's infrastructure continues to age, the number of structural deficiencies is rising. Accordingly, there is a great need and desire to replace these failing components in a quick and efficient fashion. Prefabricated elements for structures such as bridges and parking decks are commonly implemented in this process in order to save both time and money. These prefabricated elements are often subjected to moving live loads during construction and repair which, consequently, result in differential movements occurring across the joints connecting the elements of these structures. Potential reductions in joint capacity, joint stiffness, and structural durability are the byproducts …

Data Driven, Performance Based Parking Management In A University Setting, Brian Maleck

All Theses

With university enrollment increasing, campuses are becoming under increased strain for parking. More students results in more cars on an already stressed parking infrastructure. In many instances, university parking management offices are being asked to accommodate this increase in parking without the construction of new parking infrastructure. In order to accommodate these demands, better parking management is required.
This research develops a framework to evaluate current parking management practices and pinpoint methods to improve upon current practices. The framework is generalized for use by any size and type of university. Clemson University's campus in Clemson, SC was used as a …

Probabilistic Back Analysis Of Geotechnical Systems, Lei Wang

All Theses

This thesis is aimed at applying the probabilistic approaches for back analysis of geotechnical systems. First, a probabilistic back-analysis of a recent slope failure at a site on Freeway No. 3 in northern Taiwan is presented. The Markov Chain Monte Carlo (MCMC) simulation is used to back-calculate the geotechnical strength parameters and the anchor force. These inverse analysis results, which agree closely with the findings of the post-event investigations, are then used to validate the maximum likelihood method, a computationally more efficient back-analysis approach. The improved knowledge of the geotechnical strength parameters and the anchor force gained through the probabilistic …

An Analysis Of A Missing Design Concept For Sustainable Buildings: Addressing The Safety And Health Of The Construction Worker, Christopher Almond

All Theses

Construction work is inherently dangerous. The 2010 U.S. Bureau of Labor Statistics show the construction industry had the most fatal injuries of all industry sectors, 17%. U.S. regulations place the responsibility for construction safety on the construction contractor. However, owners and designers have the potential to affect the safety of the construction workforce. Owners have gotten more involved in promoting the safety and health of construction workers in recent years; however, studies show that the safety and health of the construction workforce is not typically considered by designers.
The Naval Facilities Engineering Command (NAVFAC) - the U.S. Navy's systems command …

Flexural Strength Reliability Of Visually Graded Southern Pine Dimensional Lumber, Mengyu Yang

All Theses

The reference design values published in the National Design Specification (NDS) for Wood Construction are derived from full-scale testing of lumber samples performed in the 1980s. This testing program is commonly known as the In-GradeTest Program. Selective annual sample tests of visually graded Southern Pine lumber from 1994 to 2010 revealed an overall decreasing trend in the mechanical properties. Because of this alarming observation, a new round of full-scale In-Grade test of visually graded Southern Pine was initiated in 2010. The new test data indicated significant reductions in certain design values published in the current design code (2005 NDS). …

Impact Of Channel Conditions On Existing Scour Measuring Instruments, Md Nasimul Hoque Chowdhury

All Theses

Scour around bridge piers and abutments, is the prominent reason for bridge failures. Bridge failures have substantial effects on economy and human lives. About 60% of the total bridge failures in U.S. can be attributed to scour. In the past, scour has been responsible for several million dollars in bridge repair cost. Given the threat to the bridge infrastructure due to scour, the U.S. Federal Highway Administration has proposed several countermeasures to reduce the impact of bed degradation. One of these countermeasures that is particularly relevant during peak flow periods is the real-time scour monitoring. Scour monitoring involves real-time data …

Application Of Parameter Estimation And Calibration Method For Car-Following Models, Md Rahman

All Theses

Both safety and the capacity of the roadway system are highly dependent on the car-following characteristics of drivers. Car-following theory describes the driver behavior of vehicles following other vehicles in a traffic stream. In the last few decades, many car-following models have been developed; however, studies are still needed to improve their accuracy and reliability.
Car-following models are a vital component of traffic simulation tools that attempt to mimic driver behavior in the real world. Microscopic traffic simulators, particularly car-following models, have been extensively used in current traffic engineering studies and safety research. These models are a vital component of …

Corrosion Activity In Precast Concrete Elements And Cementitious Closure Pours, Shabi Abbas Udaipurwala

All Theses

The use of prefabricated elements in the construction of highway bridges has been a common practice in the United States since 1950s. Precast concrete adjacent box beam girder bridges are quite popular given that the precast elements not only have structural capacity to span across the supports, but also form the bridge deck. These bridges have generally performed well during the initial years after construction, but recent failures in Pennsylvania and Indiana have aroused a nationwide alarm to investigate the causes of failure and find solutions to repair these bridges or develop design for new replacement bridges. It was found …

Development Of A Rating System To Measure The Vulnerability Of Residential Homes To Natural Hazards, Corey Cattano

All Dissertations

Hurricanes and tropical storms continue to damage the United States coastline where population migration increases and tourism thrives. Extended dry spells, high winds, and hot summers in the Mountain and Pacific West regions promote ideal conditions for seemingly uncontrollable wildfires. Additionally, the increased frequency of unstable climate conditions foretells signs of Mother Nature not letting up. With recent events such as Superstorm Sandy and the Waldo Canyon wildfires in mind, there is a strong need to improve hazard mitigation techniques in residential homes and encourage resilient building methods. Research within this field is challenging due to the lack of descriptive …

Calibration Of Microscopic Traffic Flow Models Considering All Parameters Simultaneously, Victor Hugo Molano Paz

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study proposes a methodology to calibrate microscopic traffic flow simulation models. The proposed methodology has the capability to calibrate simultaneously all the calibration parameters as well as demand patterns for any network topology. These parameters include global and local parameters as well as driver behavior and vehicle performance parameters; all based on multiple performance measures, such as link counts and speeds. Demand patterns are included in the calibration framework in terms of turning volumes.

A Simultaneous Perturbation Stochastic Approximation (SPSA) algorithm is proposed to search for the vector of the model‟s parameters that minimizes the difference between actual and …

Phosphorus Removal From Ebpr Sludge Dewatering Liquors Using Lanthanum Chloride, Aluminum Sulfate And Ferric Chloride, Michael Strileski

UNLV Theses, Dissertations, Professional Papers, and Capstones

In wastewater treatment, enhanced biological phosphorus removal (EBPR) is becoming an increasingly popular alternative to chemical precipitation (CP) because of its lower costs and reduced sludge production. However, downstream solids handling processes such as digestion, sludge storage and dewatering promote an undesirable release (i.e. secondary release) of polyphosphate that was stored within EBPR sludge. Released phosphate is recycled to the head of the plant with the liquors of sludge dewatering processes. The concentration of phosphate in recycle streams from EBPR systems can be one to two orders of magnitude higher than the influent phosphorus concentration entering the EBPR system. Plants …

Volatile Organic Compound Emissions From Surface Coating Facilities: Characterization Of Facilities, Estimation Of Emission Rates, And Dispersion Modeling Of Off-Site Impacts, Annabrabha Athappan, Sulak Sumitsawan, Roja Haritha Gangupomu, Ketwalee Kositkanawuth, Parthen Parikh, Benjamin Nmai Afotey, Neelesh Sule, Sahithi Raj Kalidindi, Melanie L. Sattler, Yvette Pearson Weatherton

Civil Engineering Faculty Publications - Archive

Surface coating facilities are major sources of volatile organic compounds (VOCs) in urban areas. These VOCs can contribute to ground-level ozone formation, and many are hazardous air pollutants (HAPs), including xylene, ethylbenzene, and toluene. This project was conducted in order to provide information for updating the Texas Commission on Environmental Quality (TCEQ), USA, permit by rule for Surface Coating Facilities. Project objectives were: 1) To develop a database of information regarding surface coating facilities in Texas; 2) To estimate maximum emission rates for various VOC species from surface coating facilities in Texas; 3) To conduct dispersion modeling to estimate off-site …

Accuracy Analysis Of Parallel Method Based On Non-Overlapping Domain Decomposition Method, Moonho Tak, Yooseob Song, Hye-Kwan Jeon, Taehyo Park

Civil Engineering Faculty Publications

In this paper, an accuracy analysis of parallel method based on non-overlapping domain decomposition method is carried out. In this approach, proposed by Tak et al.(2013), the decomposed subdomains do not overlap each other and the connection between adjacent subdomains is determined via simple connective finite element named interfacial element. This approach has two main advantages. The first is that a direct method such as gauss elimination is available even in a singular problem because the singular stiffness matrix from floating domain can be converted to invertible matrix by assembling the interfacial element. The second is that computational time and …

A New Framework For Flooding Control In Regulated River Systems, Elizabeth Akemi Kanashiro

Boise State University Theses and Dissertations

This thesis presents a case study on the application of a dynamic framework for the intelligent control of flooding in the Boise River system in Idaho. This framework couples a robust and numerically efficient hydraulic routing approach with the popular multi-objective, non-dominated Sorting Genetic Algorithm II (NSGA-II). The novelty of this framework is that it allows for controlled flooding when the conveyance capacity of the river system is exceeded or is about to exceed. Controlled flooding is based on weight factors assigned to each reach of the system depending on the amount of damage that would occur should a flood …

Risk Assessment Model For Pipe Rehabilitation And Replacement In A Water Distribution System, Jan C. Devera

Master's Theses

The efficient delivery of potable water for a community through its distribution system has historically been the backbone of nearly all metropolitan developments. Much of these systems are comprised of pipe networks made of various materials including concrete, iron, PVC, and even steel. As these communities expand and urbanize, water demand and population density simultaneously increase. This develops higher strains and stresses in the community‟s water distribution network causing pipes to corrode, crack, or rupture prematurely while in service. As a result, the deterioration of water distribution systems in growing cities is increasingly becoming a major concern for our nation. …

Optimizing Scm Proportions To Meet Multiple Performance Characters Of Ternary Concrete Mixtures Using Simplex-Centroid Design And Analysis Techniques, Sujay Math

All Dissertations

High performance concrete mixtures often contain multiple cementitious components. Among these, cement is the most expensive in addition to having a higher carbon footprint. Life cycle assessment of cement production reveals that the cement content is the most important factor in determining a concrete mixture's embodied energy and carbon footprint. Compressive strength, an important property of concrete, is directly related to the quantity of cement used in the mixture. However, higher quantities of cement lead to durability issues. The increased concerns about the durability of concrete over the past decade have increased focus on improving the long-term performance of concrete …

Freeze-Thaw Durability Of Portland Cement Concrete Due To Addition Of Crumb Rubber Aggregates, Shubhada Gadkar

All Dissertations

Ground tire rubber also known as crumb rubber has been widely used in asphalt concrete over the past several years due to its ability to improve temperature susceptibility of asphalt binders and enhance the performance of asphalt pavements. However, its inclusion in portland cement concrete is comparatively recent and more research is needed before adopting it as a regular construction material. Past research has shown that while addition of rubber aggregates in concrete reduces its compressive, tensile and flexural strengths, but is useful in improving durability properties as freeze-thaw resistance due to the ability of crumb rubber to generate an …

Hydraulic Impact Of Porosity Distribution And Hydrologic Characterization Of Porous Pavements, William Martin

All Dissertations

This research focused on the hydrologic characterization of porous pavement and pavement properties that can affect its hydraulic behavior. The first of these properties investigated was the presence of a vertical porosity distribution which can significantly impact the infiltration rate. A method utilizing image analysis was tested and experimentally verified. The representative elemental area (REA) was needed for this imaging method and was found to be 83.9 cm2 (13 in2). To convert the porosity distribution into a permeability distribution the relationship between porosity and permeability was found using homogenous samples. From the resulting permeability distribution an effective permeability was found …

Robust Design Optimization: Ensuring Robustness Against Uncertainty In Structural Design, Zhifeng Liu

All Dissertations

In structural design, if robustness is overlooked in design process, the acquired design is likely to have large variation in its performance due to uncertainties. In that there is no design specification that explicitly considers the robustness against such uncertainties, this dissertation elucidates design methodologies for use in selecting the optimal design parameters to minimize the effect of the hard to reduce or irreducible uncertainties on structural performance, i.e., maximizing the robustness. However, due to limited resources, structural designs are also constrained by available resources and budget. Consequently, in that a tradeoff relationship exists between the robustness and cost (i.e. …