Civil and Environmental Engineering Commons^™

Bs News November/December

Building Services Engineering

No abstract provided.

Approximating The Seismic Amplification Effects Experienced By Solar Towers Mounted On The Rooftops Of Low-Rise Industrial Buildings, Peter Luiz Balla

Master's Theses

This thesis investigates the acceleration amplification experienced by solar towers mounted on the rooftops of low-rise industrial buildings during a seismic event. Specifically, this thesis looks to assess the validity of using amplification factors adopted by the ASCE 7-05Minimum Design Loads for Buildings and Other Structures to approximate seismic acceleration amplification for roof-mounted solar towers. To investigate the validity of the ASCE 7-05 amplification factors, this thesis conducts timehistory analyses of three theoretical solar towers mounted on the roof of a case study building. The time history analyses are conducted in the finite element computer modeling program SAP 2000 using …

Absorption Simulation ( Absim ) Software Development, Vipul Vishnu Bhat, Ming Qu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Researchers working on air conditioning systems currently use a software called ABSIM ( Absorption Simulation ) to evaluate current absorption systems or simulate new system designs. ABSIM was developed at Oak Ridge National Labs in the 1980s and the latest platform it is compatible with is Windows XP. ABSIM is not compatible on newer platforms and is not very user friendly. A lot of the actions involved in using ABSIM aren’t very intuitive. The goal is to develop a more user friendly simulation program that is based off of ABSIM and see to it that the program can be deployed …

Compression Testing And Failure Modes Of Steel-Concrete Composite (Sc) Structures For Nuclear Containment, Patrick Michael Wanamaker, Amit H. Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Although being able to provide much cleaner power than burning coal and other fossil fuels, nuclear power plants are still a tough sell to the general public due to their history of being spontaneously dangerous. The containment structures surrounding these nuclear plants, however, can play a huge role in reducing the risks associated with them. Relatively new designs for these containment assemblies, known as SC (steel-concrete composite) structures, aim to increase the strength and durability of the containment facilities while keeping costs down. By varying the spacing between shear studs, the ratio of concrete to steel, and the ratio of …

Environmental Monitoring In Preparation For The Installation Of A Green Roof, Andrew N. Martin, Ming Qu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Green roofs are becoming an increasingly popular way to improve the environmental, economic, and aesthetic performance of both new and existing buildings. Along with the green roofs themselves, it is also common to install sensors to measure various environmental parameters that are affected by or important to the operation of the roof such as precipitation, temperature, and runoff. However, for most of these systems, the sensors are installed at the same time or even after the green roof. Therefore, no before-and-after comparisons can be made for those roofs. To account for this missing data, monitoring equipment was installed on a …

Plants As Bio-Indicators Of Subsurface Conditions: Impact Of Groundwater Level On Btex Concentrations In Trees, Jordan Wilson, Rachel Bartz, Matt Limmer, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Numerous Studies Have Demonstrated Trees' Ability to Extract and Translocate Moderately Hydrophobic Contaminants, and Sampling Trees for Compounds Such as BTEX Can Help Delineate Plumes in the Field. However, When BTEX is Detected in the Groundwater, Detection in Nearby Trees is Not as Reliable an Indicator of Subsurface Contamination as Other Compounds Such as Chlorinated Solvents. Aerobic Rhizospheric and Bulk Soil Degradation is a Potential Explanation for the Observed Variability of BTEX in Trees as Compared to Groundwater Concentrations. the Goal of This Study Was to Determine the Effect of Groundwater Level on BTEX Concentrations in Tree Tissue. the Central …

Phytotechnologies - Preventing Exposures, Improving Public Health, Heather F. Henry, Joel Gerard Burken, Raina M. Maier, Lee A. Newman, Steven Rock, Jerald L. Schnoor, William A. Suk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Phytotechnologies Have Potential to Reduce the Amount or Toxicity of Deleterious Chemicals and Agents, and Thereby, Can Reduce Human Exposures to Hazardous Substances. as Such, Phytotechnologies Are Tools for Primary Prevention in Public Health. Recent Research Demonstrates Phytotechnologies Can Be Uniquely Tailored for Effective Exposure Prevention in a Variety of Applications. in Addition to Exposure Prevention, Plants Can Be Used as Sensors to Identify Environmental Contamination and Potential Exposures. in This Paper, We Have Presented Applications and Research Developments in a Framework to Illustrate How Phytotechnologies Can Meet Basic Public Health Needs for Access to Clean Water, Air, and Food. …

The Bridge Newsletter Winter 2013, Missouri University Of Science And Technology

The Bridge Newsletter

-Roof turned into teaching tool
-Prakash recognized
-Alumna of the Year
-Super Miners

Development Of Long Carbon Fiber-Reinforced Concrete For Dynamic Strengthening, Zahra S. Tabatabaei, Jeffery S. Volz, Benjamin P. Gliha, Darwin I. Keener

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper discusses the development and testing of long carbon fibers-fibers 75 mm long or longer-to improve the resistance of reinforced concrete to dynamic loading, such as blasts and impact. In the past, attempts to use long fibers in concrete have failed as a result of both balling (agglomeration) and poor dispersion of the fibers. In the present study, two types of long carbon fibers were developed and optimized for their use in reinforced concrete. The resulting long carbon fiber-reinforced concrete (LCFRC) was subsequently evaluated through impact and blast testing. Full-scale blast testing revealed that these fibers significantly increased the …

Dynamic Nonlinearity And Nonlinear Single-Degree-Of-Freedom Model For Cable Net Glazing, Ruo Qiang Feng, Jihong Ye, Guirong Yan, Jin Ming Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Nonlinear Vibration Differential Equation and Vibration Frequency of Cable Net Glazing Subject to Earthquake Loading Was Determined, and a Geometrically Nonlinear Single-Degree-Of-Freedom Model for Cable Net Glazing Was Developed. the Nonlinear Response Spectra Were Established, and Nonlinear Time History Analysis with Finite Element (FE) Models Was Conducted to Verify Them. the Nonlinear Vibration Differential Equation and Frequency Obtained as Described in This Paper Provide a Basis for the Nonlinear Single-Degree-Of-Freedom Model for Cable Net Glazing. the Analytical Formula for the Nonlinear Frequency with a Simplified Expression is Highly Precise and Convenient for Use in Engineering Practice. for Larger-Amplitude Seismic …

Issue Brief: Saving By Mitigating, University Of Louisville, New England Environmental Finance Center

Sustainable Communities Capacity Building

Natural disasters can cause loss of life, inflict damage to buildings and infrastructure, and have devastating consequences for a community’s economic, social, and environmental well-being. Hazard mitigation means reducing damages from disasters.

Local governments have the responsibility to protect the health, safety, and welfare of their citizens. Proactive mitigation policies and actions help reduce risk and create safer, more disaster-resilient communities. Mitigation is an investment in your community’s future safety, equity, and sustainability.

Comparison Of Prestress Losses For Pedestrian Bridges Constructed With High-Strength Concrete And High-Strength Self-Consolidating Concrete, John J. Myers, Kurt E. Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract Two precast prestressed high-strength concrete and high-strength self-consolidating concrete pedestrian bridges were designed and erected in Rolla, Missouri, for an in situ investigative study to monitor time-dependent losses. Using the temperature and strain data monitored by the vibrating wire strain gauges within the beam cross sections, time-dependent losses were determined and compared between the bridges and various empirical expressions presented by AASHTO and the Precast/Prestressed Concrete Institute. © 2013 American Society of Civil Engineers.

Distribution And Accumulation Of Trichloroethylene And Trichloroacetic Acid In Hybrid Poplars, Lucas Odom, Joel Gerard Burken, Lee Newman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hybrid Poplar Trees Are Known to Take Up Trichloroethylene (TCE) into above Ground Tissues, Where It Degrades into the Metabolites Trichloroacetic Acid (TCAA), Dichloroacetic Acid, and Trichloroethanol and Where Parent Chlorinated Solvents Volatilize to the Atmosphere. based on This Knowledge, Numerous Phytoremediation Applications Have Been Implemented for TCE and Other Chlorinated Solvents. Sampling of Plant Tissues Has Proven Effective for Phytoforensic and Phytoscreening Applications in Assessing Sites and Evaluating the Efficacy of Phytoremediation. However, Little is Known About the Appropriate Exposure Times and Sampling Locations Required to Obtain an Accurate Assessment of TCE and Metabolites. in This Study, Hybrid Poplars …

Bs News September/October

Building Services Engineering

No abstract provided.

Numerical Simulation Of Vortex-Induced Vibration Of Two Circular Cylinders Of Different Diameters At Low Reynolds Number, Ming Zhao, Guirong Yan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Two-Degree-Of-Freedom Vortex-Induced Vibration (VIV) of Two Rigidly Coupled Circular Cylinders of Different Diameters at a Low Reynolds Number of 250 is Investigated Numerically. While the Diameter Ratio and the Mass Ratio Are Kept Constant, the Study is Focused on the Effect of the Position Angle of the Small Cylinder on the Lock-In Regime of the VIV. Simulations Are Carried Out for Position Angles Α of the Small Cylinder Ranging from 0° to 180° with an Interval of 22.5° and the Reduced Velocities Ranging from 1 to 15 with an Increment of 1. in Order to Find the Effect of the …

Directional Phytoscreening: Contaminant Gradients In Trees For Plume Delineation, Matt A. Limmer, Mikhil K. Shetty, Samantha Markus, Ryan Kroeker, Beth L. Parker, Camilo Martinez, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tree Sampling Methods Have Been Used in Phytoscreening Applications to Delineate Contaminated Soil and Groundwater, Augmenting Traditional Investigative Methods that Are Time-Consuming, Resource-Intensive, Invasive, and Costly. in the Past Decade, Contaminant Concentrations in Tree Tissues Have Been Shown to Reflect the Extent and Intensity of Subsurface Contamination. This Paper Investigates a New Phytoscreening Tool: Directional Tree Coring, a Concept Originating from Field Data that Indicated Azimuthal Concentrations in Tree Trunks Reflected the Concentration Gradients in the Groundwater Around the Tree.To Experimentally Test This Hypothesis, Large Diameter Trees Were Subjected to Subsurface Contaminant Concentration Gradients in a Greenhouse Study. These Trees …

Evaluating Satellite Products For Precipitation Estimation In Mountain Regions: A Case Study For Nepal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha

Publications and Research

Precipitation in mountain regions is often highly variable and poorly observed, limiting abilities to manage water resource challenges. Here, we evaluate remote sensing and ground station-based gridded precipitation products over Nepal against weather station precipitation observations on a monthly timescale. We find that the Tropical Rainfall Measuring Mission (TRMM) 3B-43 precipitation product exhibits little mean bias and reasonable skill in giving precipitation over Nepal. Compared to station observations, the TRMM precipitation product showed an overall Nash-Sutcliffe efficiency of 0.49, which is similar to the skill of the gridded station-based product Asian Precipitation-Highly Resolved Observational Data Integration Towards Evaluation of Water …

Dynamic Properties Of Fine-Grained Soils Engineered With A Controlled Organic Phase, B. Bate, H. Choo, S. E. Burns

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Soils with high organic content are frequently encountered beneath earthquake sensitive infrastructure, such as bridges or levees. Historically, the dynamic properties of these organically rich soils have been difficult to predict due to the heterogeneity of the natural organic matter that is found in natural soils, even though their response to dynamic loading remains critical to assessing the ongoing stability of the infrastructure. In this study, an experimental investigation was performed on a montmorillonite soil that was modified with a controlled organic phase. Quaternary ammonium cations were exchanged onto the soil particle surfaces through cation exchange with the clay's naturally …

Implementation Of Integrated Project Delivery On Department Of Navy Military Construction Projects, Christopher S. Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

The concept of the project delivery system refers to the overall processes by which a project is designed, constructed, and/or maintained. There are many different types of project delivery systems to fit particular situations involving the owner and his intended project. The project delivery system is what establishes the framework that enables a construction project to be developed and ultimately executed.

The construction industry has observed that projects (both private and public) frequently suffer from factors such as adversarial relationships, low roductivity, high inefficiency and rework, frequent contractual disputes concerning who was at fault, and lack of innovation. Not only …

Relevance Of The Thorpe Length Scale In Stably Stratified Turbulence, Benjamin D. Mater, Simon M. Schaad, Subhas Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Direct numerical simulations of stably stratified turbulence are used to compare the Thorpe overturn length scale, LT, with other length scales of the flow that can be constructed from large-scale quantities fundamental to shear-free, stratified turbulence. Quantities considered are the turbulent kinetic energy, k, its dissipation rate, ε, and the buoyancy frequency, N. Fundamental length scales are then the Ozmidov length scale, LO, the isotropic large scale, Lkε, and a kinetic energy length scale, LkN. Behavior of all three fundamental scales, relative to LT, is shown to be a function of the buoyancy strength parameter NTL, where TL = k/ε …

Modified Time Of Setting Test For Fly Ash Paste And Fly Ash-Soil Mixtures, Xin Kang, Gi Chun Kang, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A survey of current literature has revealed that the testing protocol for determining the time of setting of fly ash-soil mixtures is not available. Although the current ASTM standard recommends using the Vicat needle method with a water-to-fly ash weight ratio of 0.35, it was originally proposed for testing the time of setting of cement. The current study showed that the Vicat needle method yielded poor test results for some common fly ashes. Moreover, the water-to-fly ash weight ratio of 0.35 may not be appropriate for some fly ashes because the chemical components are varied in different fly ashes. Therefore, …

Centrifuge Modeling And Mitigation Of Manhole Uplift Due To Liquefaction, Gi Chun Kang, Tetsuo Tobita, Susumu Iai, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Because low-compacted trench backfill around a manhole is normally liquefiable, the manhole could suffer uplift damage associated with soil liquefaction during a strong earthquake. In this study, 22 dynamic centrifuge models were tested to investigate the response of a buried manhole subjected to a dynamic load. The models were tested under 20g, and a substitute pore fluid was used to avoid the scaling law conflict between the dynamic and diffusion processes. It was found that excess pore water pressure is one of the contributing factors to the magnitude of the manhole uplift. Using this result, new mitigation methods against the …

Portable Pressure Device To Evaluate Lateral Formwork Pressure Exerted By Fresh Concrete, Ahmed F. Omran, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Use of a reliable and accurate measuring system to determine lateral pressure exerted on formwork by self-consolidating concrete can lead to economic and safe formwork systems. In this paper, a portable and field-compatible pressure device is developed to enable factors affecting lateral pressure of fresh concrete on formwork system to be explored prior to conducting onsite full-scale tests. The pressure device requires a sample of 16 L of fresh concrete to determine lateral pressure envelope that can be exerted by a concrete column of up to 13 m in height. The pressure device enables the simulation of such concrete head …

Wind-Induced Torsion Vibration Of The Super High-Rise Building Of Shenzhen Energy Center, Feng Ruo-Qiang, Ye Jihong, Guirong Yan, Li Qing-Xiang, Yao Bin

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Synchronous Multipoint Scanning System Technique in Wind Tunnel Tests and Random Vibration Theory Method Were Used to Analyze the Wind-Induced Torsion Vibration of Some Irregularly Shaped Super High-Rise Buildings in Downtowns. the Torsion Vibration Modes and the Spectra of Torsion Wind Load Were Studied, and the Proportions of Mean Wind Torsion, Inertia Torsion and the Mass Eccentricity Torsion Caused by Horizontal Inertia Forces Are Discussed. the Following Conclusions Can Be Drawn. First, the Third and Fourth Modes Have Torsion Vibration Shapes, and their Frequencies Are in the High-Energy Area of the Spectra of the Torsion Wind Load; the Third …

Bs News July/August

Building Services Engineering

No abstract provided.

Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs

Master's Theses

The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings.

The work of this thesis is divided into four phases. First, …

Long-Term Low Do Enriches And Shifts Nitrifier Community In Activated Sludge, Guoqiang Liu, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In the activated sludge process, reducing the operational dissolved oxygen (DO) concentration can improve oxygen transfer efficiency, thereby reducing energy use. The low DO, however, may result in incomplete nitrification. This research investigated the long-term effect of low DO on the nitrification performance of activated sludge. Results indicated that, for reactors with 10- and 40-day solids retention times (SRTs), complete nitrification was accomplished after a long-term operation with a DO of 0.37 and 0.16 mg/L, respectively. Under long-term low DO conditions, nitrite oxidizing bacteria (NOB) became a better oxygen competitor than ammonia oxidizing bacteria (AOB) and, as a result, no …

Precast/Prestressed Concrete Truss-Girder For Roof Applications, Peter S. Samir

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Steel trusses are the most popular system for supporting long span roofs in commercial buildings, such as warehouses and aircraft hangars. There are several advantages of steel trusses, such as lightweight, ease of handling and erection, and geometric flexibility. However, they have some drawbacks, such as high material and maintenance cost, and low fire resistance. In this paper, a precast concrete truss is proposed as an alternative to steel trusses for spans up to 160 ft. without intermediate supports. The proposed design is easy to produce and has lower construction and maintenance costs than steel trusses. The proposed design is …

Pump Controller Design For Variable Primary Flow Configuration Systems, Yifan Shi

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Pump systems are utilized widely in Heating, Ventilation and Air-Conditioning (HVAC) systems. There are mainly three configuration types: (1) the constant primary-only flow configuration, (2) the constant primary/variable secondary flow configuration, and (3) the variable primary-only flow configuration. This thesis focuses on finding the optimal control strategy for it and programming a controller for easy in-field usage.

In this thesis, the pump brake horse power (BHP) of the three pump configurations is simulated and compared using varying control methods. The best pump efficiency staging and DP reset control methods are implemented into the pump controller. A one month field experiment …

Sustainable Urban Rail Trails: Designing The Cross Kirkland Corridor, Mia Cooledge

Scripps Senior Theses

This thesis is a guide to building a sustainable rail-trail, wherein I focus on invasive species removal, green pavement, and creating an inviting space with the inclusion of integrated art. When the City of Kirkland, WA purchased the 5.75 mile long section of railroad going through the city, I approached city manager Kurt Triplett to ask about his plans for the corridor. He liked the idea of aiming for a sustainable trail, so I wrote a guide to building an environmentally friendly trail based on a number of prominent readings on sustainable design.