Civil and Environmental Engineering Commons^™

The Study Of Screws Under Bending For Curtain Wall Head And Sill Anchors, Humberto Madero Mcentee

Civil Engineering Theses - Archive

The study of screws under bending is a very important topic for the solution of anchors (connections) of the vertical members of a Curtain Wall or Storefront that connects top and bottom thru Head and Sill anchors. When there are shims that create a gap between the connected anchor and the structure that connects to, the screws connecting the anchor to the structure would be under bending; very few or any tests are available showing the capacity of a screw under bending; this thesis would present tests and theory of screws under bending, and discussion/clarification of the behavior of these …

Applications Of Ultra-High Performance Fiber-Reinforced Concrete On Flexural Structural And Architectural Members, Venkatesh Babu Kaka

Civil Engineering Theses - Archive

This thesis presents the test results of a study on flexural and shear behavior of Ultra-High-Performance Fiber-Reinforced concrete (UHP-FRC) beams, reinforced with Grade 60 steel (ASTM A615/A615M), Grade 100 steel (ASTM A1035/A1035M) and Basalt fiber reinforced polymer (BFRP) bars. Ultra-high-performance fiber-reinforced concrete (UHP-FRC) has high compressive strength (> 22 ksi (150 MPa)) and exceptional compressive ductility. The use of UHP-FRC provides new opportunities for future infrastructure. However, structural design criteria have not been developed to fully utilize UHP-FRC’s excellent mechanical properties. Maximum useable compressive strain, ecu, specified in the current design codes (ACI 318 Building Code and AASHTO LRFD Bridge …

A Comparison Of Smart City Indicators For Three Top Ten Us Cities, Rasoul Adnan Abbas

Civil Engineering Theses - Archive

The world population has been increasing each year, and the immigration from rural to urban cities has increased as well. The United Nations has estimated that more than 66% of people worldwide live in urban area, and this urbanization trend will continue to increase, thereby generating challenges to the cities as they strive to provide health care, schools, and transportation. The urban population explosion has also caused problems to the environment and overall urban economy as the need for more housing, jobs, and community services require smart solutions. The term, smart city, has many definitions, but all of them agree …

Investigation Of Reuse Of Coal Fly Ash To Mitigate Landfill Methane Gas, Amin Homaei

Civil Engineering Theses - Archive

Methane (CH4) is a powerful greenhouse gas (GHG), contributing 32% of current climate forcing (US EPA, 2015). In 2014 the White House released the “Strategy to Cut Methane Emissions” as part of the Climate Action Plan. Landfills are one of the strategy’s 4 key sectors, contributing 18% of US methane emissions (US EPA, 2013). Even when landfills capture methane and burn it to produce electricity, around 25% of methane still leaks through landfill covers (US EPA, 2005). In natural environments, iron oxides, manganese oxides, nitrates, and sulfates have been shown to stimulate microbial anaerobic oxidation of methane (AOM) (Sivan et …

Design And Evaluation Of Modified Centerline Rumble Strips, Yong-Rak Kim, Tae Sun You, Laurence Rilett

Nebraska Department of Transportation: Research Reports

A centerline rumble strip (CLRS) is primarily installed on the centerline of undivided two-lane and two-way roadways to alert drivers that they are moving out of their intended travel lane. The main purpose of CLRSs is to reduce crossover collisions typically caused by inattentive, distracted, drowsy, or fatigued drivers. Despite the safety benefits, CLRSs that were milled over or adjacent to the centerline joint may increase or accelerate the deterioration and degradation of the pavement structure, which has been observed in Nebraska pavements. In this research project, new (or modified) CLRS designs were sought to reduce pavement damage, while satisfying …

Structural Competency And Environmental Soundness Of The Recycled Base Materials In North Texas, Mohammad Faysal

Civil Engineering Dissertations - Archive

Aggregates, which are derived from natural resources, are the most important raw materials used in pavement construction; however, depletion of the natural resources, increasing labor costs, and environmental concerns have led us to look for alternatives. Recycled materials, such as recycled crushed concrete aggregate (RCCA) and reclaimed asphalt pavement (RAP), can be used as an alternative to natural aggregates and can be obtained from construction of newer structures and demolition of existing structures, such as buildings, bridges, pavement, etc. Recycled materials can reduce the cost, depletion of natural resources, and construction debris. The properties of recycled materials are source-dependent, which …

Subcontracting And The Survival Of Plants In The Road Construction Industry: A Panel Quantile Regression Analysis, Dakshina G. De Silva, Georgia Kosmopoulou, Carlos Lamarche

Economics Faculty Publications

This paper investigates how subcontracting parts of contracted work shapes entrants’ success and survival. We find that newly developed quantile regression approaches can be adapted to study survival of firms competing for government contracts in road construction. The method is applied on a data set that includes patterns of firm entry, exit and auction related information. We find an apparent increase in the business life of firms who subcontract out part of their projects. In Texas, these subcontracting effects appear to be more pronounced for firms with few or no options outside the industry, and among firms who contract out …

A Quantitative Model For Truck Parking Utilization With Hours Of Service Regulations, Alexis Christine Gaddy

Industrial Engineering Undergraduate Honors Theses

Continual growth in traffic volume on U.S. Highways and insufficient parking for commercial trucking vehicles has led to significant safety concerns for truck drivers. Hours of Service (HOS) regulations dictate driving and rest periods of truck drivers. When a truck driver must stop as designated by the HOS regulations and the nearest parking location is at capacity, the trucker must either continue driving past the HOS limit or park in an undesignated and possibly illegal or unsafe spot such as an off-ramp. The combination of these two variables play an important role in the safety of truck drivers on a …

Development Of A New Joint System For A Circular-Shaped Infrastructure, Sugyu Lee

Civil Engineering Dissertations - Archive

This dissertation focused on development of new carbon fiber joint systems for all types of underground gravity and sewer pipe systems. Specifically, the external CFRP wrap and, particularly, the carbon fiber reinforced polymer (CFRP) internal coupler can be used for concrete pipes with regular or reduced wall thicknesses. The concrete pipes with reduced wall thickness are classified as semi-rigid pipe and are referred to as thin-wall (TW) concrete pipe. The performance of the CFRP coupler is presented in this report based on full-scale experimental tests and three dimensional non-linear finite element studies for regular and thin wall pipes. Finally, design …

Long-Term Shear Investigation Of Polypropylene Fiber-Reinforced Concrete Beams, Michael Daniels

Civil Engineering Dissertations - Archive

This study investigates the long-term influence of polypropylene fibers on the shear strength and failure behavior of longitudinally reinforced concrete beams, with or without stirrups, subjected to accelerated aging conditions. For this study, 32 large scale short beams with different volume fractions of polypropylene fibers were casted and tested in the Civil Engineering Laboratory Building (CELB) at the University of Texas at Arlington: (1) Control reinforced concrete beams (RC); (2) Reinforced concrete beams with minimum stirrups (RCS) according to ACI 318; (3) Synthetic fiber-reinforced concrete beams with Vf=0.5% (SNFRC 0.5%), which correspond to 7.67 lbs./yd3 (4.55 kg/m3)’; and (4) Synthetic …

Modular House Revival, Kevin Chiang, Spencer Dilley, Sarah Dowthwaite, Trevor Houghton, Ryan Lefebvre, Michele Leung, Cameron Lober, Chris Martinez, Katie Mayer

Architectural Engineering

The Modular House, located in Poly Canyon, has seen extensive damage since the last caretaker left nearly ten years ago. To prevent further damage and improve the safety and appeal of the structure, we are proposing a renovation of the existing building that removes the existing cladding and partitions. By the end of Spring Quarter 2017, the Modular House will have a guardrail system replacing the wood paneling on the walls and a new steel composite deck to replace the current flooring system. The structural steel framing system will remain as is.

Bias And Other Error In Gridded Weather Data Sets And Their Impacts On Estimating Reference Evapotranspiration, Philip A. Blankenau

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Gridded weather data sets are increasingly used in a variety of hydrologic and agricultural applications due to their complete spatial and temporal coverage. One application of gridded data sets is the estimation of evapotranspiration (ET). Several operational remote sensing (RS) approaches for estimating ET, such as the SEBAL, METRIC and EEFlux models, require estimates of reference ET (ETref), where ETref is expected ET from a hypothetical reference crop of clipped grass or alfalfa. Gridded weather data provide for the computation of ETref in all areas of a remote sensing image, and therefore potentially remove the need for dense weather station …

A Tool To Evaluate Sustainability Of Pavement Maintenance Projects., Yibo Zhang

Electronic Theses and Dissertations

Pavement maintenance activities are widely regarded to be critical elements during pavement life cycle, different maintenance techniques have been used to restore or extend the service lives of pavements. However, the existing maintenance practices on pavement system have problems that impair the economic benefits, disturb the natural environment, and somewhat ignore the needs from stakeholders. To minimize these negative impacts, sustainability is an ideal way because it addresses the problems under Triple Bottom Line (TBL, refers to economy, environment, and society). Sustainability analysis within transportation or pavement industry has been studied in different countries, but the concept of sustainable pavement …

Non-Contact Based Structural Damage Assessment Using Stochastic Subspace Identification And Finite Element Model Updating., Li Yang

Electronic Theses and Dissertations

This research proposed and verified an innovative method to identify and locate structural damage using only the response of operational vibration, that is the displacement acquired by a non-contact optical method. The most efficient and economical way to detect damage within the structure is to monitor its structural health while in operation. However, the uncertainties and the randomness of ambient vibrations due to the operation and environments cause a challenge in conducting the operational analysis. Current technology limits the ability to collect data on the properties of the structure without the interruption of operation. Frequencies and mode shapes have been …

Re-Evaluation Of Acceptance Testing Criteria For Structural Masonry Using The Prism Test Method, James Bristow

UNLV Theses, Dissertations, Professional Papers, and Capstones

The current acceptance criteria for structural masonry in accordance with International Building Code allows for the prism test method to be used. However, without a proper understanding of the effects of variable material properties such as individual masonry unit compressive strength and the various material moduli of elasticity, as well as the effect of field conditions on the unit’s performance, masonry prisms may “fail” to reach the design compressive strength (f’m).

By identifying causes of failure and evaluating the failure magnitude, it is concluded that when the masonry prism test method is utilized for acceptance testing of as-built masonry structures, …

Generalized Clusterwise Regression For Simultaneous Estimation Of Optimal Pavement Clusters And Performance Models, Mukesh Khadka

UNLV Theses, Dissertations, Professional Papers, and Capstones

The existing state-of-the-art approach of Clusterwise Regression (CR) to estimate pavement performance models (PPMs) pre-specifies explanatory variables without testing their significance; as an input, this approach requires the number of clusters for a given data set. Time-consuming ‘trial and error’ methods are required to determine the optimal number of clusters. A common objective function is the minimization of the total sum of squared errors (SSE). Given that SSE decreases monotonically as a function of the number of clusters, the optimal number of clusters with minimum SSE always is the total number of data points. Hence, the minimization of SSE is …

Calibration Of Microscopic Traffic Flow Models Enabling Simultaneous Selection Of Specific Links And Parameters, Kul Prasad Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study proposes a methodology for the calibration of microscopic traffic flow simulation models by enabling simultaneous selection of traffic links and associated parameters. That is, any number and combination of links and model parameters can be selected for calibration. Most calibration approaches consider the entire network without enabling a specific selection of location and associated parameters. In practice, only a subset of links and parameters are used for calibration based on a number of factors such as expert local knowledge of the system. In this study, the calibration problem for the simultaneous selection of links and parameters was formulated …

Dynamic Risk Analysis Of Construction Delays Using Fuzzy-Failure Mode Effects Analysis, Mohammadsoroush Tafazzoli

UNLV Theses, Dissertations, Professional Papers, and Capstones

Considering the tremendous losses in the worldwide economy caused by construction delays, it is essential to invest in minimizing the risks of delays. In order to make this happen, two measures should be taken:

1) The roots and fundamental causes of delay should be identified and strategies to mitigate their risks be developed (General remedy).

2) The most significant potential causes of delay in each project should be identified and these causes should be given priority to control (Project-Specific Remedy).

The current research invests in both of the measures. To provide the general remedy, causes of delay in the construction …

Analysis Of Lid Implementation To Combat Flooding And Erosion At The University Of Arkansas Campus, Madison E. Crowl

Biological and Agricultural Engineering Undergraduate Honors Theses

The city of Fayetteville, Arkansas has experienced rapid urbanization throughout recent years as it continues to grow. Within the city, the University of Arkansas has been constantly expanding, with increased impervious surfaces as more parking lots and facilities are built. This has caused issues including flooding and stream bank erosion, specifically in Mullins Creek, which receives runoff from a large part of campus. A portion of the creek was restored, but there are still downstream issues. Low Impact Development (LID) is a type of green infrastructure that has been shown to decrease runoff and increase infiltration. EPA SWMM, a hydrologic …

A Comprehensive Resilience Framework For The Seismic Evaluation Of Hydraulic Fill Dams In North Texas, Santiago R. Caballero

Civil Engineering Dissertations - Archive

Hydraulic filling is a construction procedure that was used for earthen structures during the mid-1800s to the early 1900s; however, dams and levees that were constructed by implementing this technique had a significant potential for geotechnical hazards. Historically, most of the failures of these structures were a result of the soil cyclic liquefaction phenomenon. This phenomenon occurs when excess pore water pressure develops during cyclic loading and causes loss of effective strength in the soil. The cyclic stress approach is one of the methods widely used to assess cyclic liquefaction; however, seismic parameters (loading conditions) and soil characterization (liquefaction resistance) …

Development Of Cone Testing Device For Improved Deep Foundation Design Protocols, Hai Minh Nguyen

Civil Engineering Dissertations - Archive

A novel cone penetration test device, the P-cone, has been developed to assist in deep foundation design and this P-cone device combines features of CPTU cone sounding technologies with capabilities to perform bidirectional loading at a given soil depth condition. Using two independent systems, the P cone measures shear stress versus movements of cone shaft and stress versus penetration of the cone tip at desired depths. The P-cone can also improve the penetration depth and offer a potential application for the in situ consolidation test. Laboratory experiments of the P-cone device were successful beyond the expectation. P-cone Tests performed on …

Toward High-Resolution Flood Forecasting For Large Urban Areas - New Solutions For 1d Routing, Behzad Nazari

Civil Engineering Dissertations - Archive

The ability to forecast flow, depth, and velocity in flooding events is one of the most important needs in highly populated urban areas. Urbanization and climate change highlight the necessity to understand and accurately predict water-related hazards in urban areas due to extreme precipitation. Towards that end, this study initially assesses the impact of changes in precipitation magnitude and imperviousness on urban inundation in a flooding prone urban catchment in the Dallas-Fort Worth Metroplex. Consequently, this study focuses on identifying potential alternatives to the conventional inundation models to improve operational viability of real-time flood forecasting in urban areas by downscaling …

Development, Testing And Implementation Of Traffic Signal Performance Measures At A Local Governmental Agency, Jay Alan Grossman

Indiana Local Technical Assistance Program (LTAP) Technical Reports

The testing and implementation of traffic signal performance measures at a local government agency revolves around three main performance measures: signal detector anomaly identification, signal split failures reports and red light running identification. Signal detector anomaly identification used the Kolmogorov-Smirnov test to compare current and past detector operation and was shown to be effective in identification of anomalies. Three different types of split failure reports were utilized to determine operational issues on signal systems. Long-term longitudinal, corridor scale, and single intersection split failure reports were implemented on active signal systems and found to be effective in determining and correcting problems. …

Effect Of High Cationic Flocculant On Anaerobic Digestion Of Municipal Wastewater., Prathap D. John

Electronic Theses and Dissertations

Anaerobic digestion (AD) of municipal sludge is a widely used stabilization process at municipal wastewater treatment plants. It is highly effective in reducing sludge volume and produces methane gas which is used as fuel in the wastewater plant. Following digestion sludge is sent to a centrifuge to separate the solids from the liquids. Louisville MSD adds flocculent to material in the centrifuge to better coagulate the solids, thereby aiding in separation of the solids from the liquids. The potential for further AD, COD reduction, and methane generation of the liquid effluent from the centrifuge was unknown, particularly in regards to …

High Early-Age Strength Concrete For Rapid Repair, Matthew O. Maler

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this research was to identify High Early-Age Strength (HES) concrete batch designs, and evaluate their suitability for use in the rapid repair of highways and bridge decks. To this end, two criteria needed to be met; a minimum compressive strength of 20.68 MPa (3000 psi) in no later than 12 hours, and a drying shrinkage of less than 0.06 % at 28 days after curing. The evaluations included both air-entrained, and non-air-entrained concretes.

The cement types chosen for this study included Type III and Type V Portland cement and “Rapid Set” − a Calcium Sulfoaluminate (CSA) cement. …

Effect Of Surface Modifying Biopolymers On Sand Cohesion, Connor H. Ligeikis

Honors Scholar Theses

Coastal erosion is a substantial problem in the United States and throughout the world. A novel approach to mitigating this problem is through the application of surface-modifying biopolymers to sand on beaches. Field research conducted by Dr. Amine Dahmani has shown that these organic complexes can coat granular sediments and increase sediment cohesion, thereby decreasing the erodability of the sediment. The goal of this thesis is to quantify the impact of proprietary surface-modifying biopolymer formulations on sand cohesion in order to better engineer this innovative solution for sand retention and potentially contaminated sediment sand cap stabilization. The impact of the …

Discrete Element Analysis Of Scb Variability: Asphalt Mixtures, David Saul Renteria

Theses and Dissertations

The Semi-Circular Bending (SCB) test was modeled using the Discrete Element Method (DEM) implemented in numerical software Particle Flow Code (PFC). The fracture analysis of the SCB was studied using two mixtures gradation, Superpave and Coarse Matrix High Binder. The aggregate phase in the model was achieved by using two-dimensional aggregate images with different angularity indexes. The study of the variability of the SCB extends to the random generation of aggregate particles and air voids in the model, in addition to changing the properties at the interface between the aggregate and mastic phases. Results indicate the strong influence of the …

Bs News May/June

Building Services Engineering

No abstract provided.

Using An Altimeter-Derived Internal Tide Model To Remove Tides From In Situ Data, Edward D. Zaron, Richard D. Ray

Civil and Environmental Engineering Faculty Publications and Presentations

Internal waves at tidal frequencies, i.e., the internal tides, are a prominent source of variability in the ocean associated with significant vertical isopycnal displacements and currents. Because the isopycnal displacements are caused by ageostrophic dynamics, they contribute uncertainty to geostrophic transport inferred from vertical profiles in the ocean. Here it is demonstrated that a newly developed model of the main semidiurnal (M2) internal tide derived from satellite altimetry may be used to partially remove the tide from vertical profile data, as measured by the reduction of steric height variance inferred from the profiles. It is further demonstrated that the internal …

Estimation Of Groundwater Loads Into A Coastal Estuary Using Seawat, Antonio S. Berber Jr.

Theses and Dissertations

The research of regional groundwater flow is of vital importance at the Indian River Lagoon (IRL) due to the potential contribution groundwater flow has on nutrients into the IRL. If too many nutrients are introduced into the IRL, algal blooms could occur and impact the health of IRL system. The IRL is a coastal estuary located on the east coast of Florida. Submarine groundwater seepages (SGD) and groundwater loads into the IRL were numerically estimated by using SEAWAT, a program designed to simulate variable-density groundwater flow coupled with multi-species solute transport. Models were completed at three different study transects that …