Architectural Engineering Commons^™

A Composite Structural Steel And Prestressed Concrete Beam For Building Floor Systems, Nathan Dewit

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

Precast prestressed concrete beams, such as rectangular and inverted tee beam, currently used in residential and commercial buildings are deep, heavy, and limited to span-to-depth ratios of 15. The research proposes a composite structural steel and prestressed concrete beam that is shallow, light, easy to produce and erect, and able to achieve a span-to-depth ratio of 24. The proposed beam is designed to be used with precast columns, hollow-core planks, and a cast-in-place topping to create a moment-resisting floor system that minimizes the need for shear walls. The goal of this system is to eliminate as many of the limitations …

Monotonic Behavior Of Mississippi River Valley Silt In Triaxial Compression, Shuying Wang, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The static behavior of Mississippi River Valley silt was characterized using triaxial compression testing. Silt specimens, especially over consolidated ones, showed dilation behavior. There was no unique critical state among specimens with different over consolidation ratios (OCRs). with OCRs of 1, 2, and 8, the specimens exhibited normal behavior and dilated more as effective consolidation pressure dropped. However, for an OCR of 4, the specimens showed opposite behavior and dilated more as effective consolidation pressure rose. the friction angle of the silt was computed on the basis of several failure criteria, and the limiting strain was found to be the …

Factors Influencing Crack-Induced Tensile Strength Of Compacted Soil, Tae Hyung Kim, Tae Hoon Kim, Gi Chun Kang, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Mode I (tensile) fracture is the most commonly observed failure in Geostructure's resulting from cracks in soil. Direct or indirect tensile tests have been used to evaluate the tensile strength of geomaterials. in this paper, the unconfined penetration device and experimental procedure were modified to reduce measurement errors. It was then used to determine the tensile strength of compacted soil. Factors influencing the tensile strength of the compacted soil, including the plasticity index, rate of loading, and size of specimen were discussed in detail, as well as its reliability. Experimental results indicated that the modified, unconfined penetration technique is sufficiently …

Time-Weighted Average Spme Analysis For In Planta Determination Of Cvocs, Emily M. Sheehan, Matt A. Limmer, Philipp Mayer, Ulrich Gosewinkel Karlson, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Potential of Phytoscreening for Plume Delineation at Contaminated Sites Has Promoted Interest in Innovative, Sensitive Contaminant Sampling Techniques. Solid-Phase Microextraction (SPME) Methods Have Been Developed, Offering Quick, Undemanding, Noninvasive Sampling Without the Use of Solvents. in This Study, Time-Weighted Average SPME (TWA-SPME) Sampling Was Evaluated for in Planta Quantification of Chlorinated Solvents. TWA-SPME Was Found to Have Increased Sensitivity over Headspace and Equilibrium SPME Sampling. using a Variety of Chlorinated Solvents and a Polydimethylsiloxane/carboxen (PDMS/CAR) SPME Fiber, Most Compounds Exhibited Near Linear or Linear Uptake over the Sampling Period. Smaller, Less Hydrophobic Compounds Exhibited More Nonlinearity Than Larger, More …

Quantifying The Life Cycle Benefits Of Performance-Based Design In Sustainable Design, David Isaac Carmona

Master's Theses

ABSTRACT

Quantifying the Life Cycle Benefits of Performance-Based Design in Sustainable Design

David Carmona

For this thesis, a method is developed and tested for use with performance based design to quantify the sustainable and financial benefits of designing buildings to a structural performance level higher than Life-Safety. This paper starts to answer the question, “which would be a better investment: build structures to a performance level of Immediate Occupancy (IO) with the likelihood of less damage and downtime after an earthquake or continue to build to the building code’s implied minimum performance level of Life-Safety (LS)?”

An ASCE 7-05 designed …

The Bridge Newsletter Spring 2012, Missouri University Of Science And Technology

The Bridge Newsletter

-Light-weight foam could cushion expensive bridge repairs
-New Chancellor
-The house of the future today
-High-tech approach to project management

2012 Scholarly Productivity Report, Missouri University Of Science And Technology

Civil, Architectural and Environmental Engineering Scholarly Productivity Reports

No abstract provided.

Effects Of Nano-Copper(Ii) Oxide And Nano- Magnesium Oxide Particles On Activated Sludge, Guoqiang Liu, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Effects of nano-copper (II) oxide (nano-CuO) and nano-magnesium oxide (nano-MgO) particles on activated sludge endogenous respiration (aerobic digestion), biochemical oxygen demand (BOD) biodegradation, and nitrification were investigated through respiration rate measurement. for comparison, the effects of Cu (II) and Mg (II) ions on activated sludge were also studied. Results indicated that soluble Cu (II) has half maximum inhibitory concentration (IC50) values of 19, 5.5, 53, and 117 mg Cu/L for endogenous respiration, BOD biodegradation, ammonium oxidation, and nitrite oxidation, respectively. However, nano-CuO only inhibited BOD biodegradation at 240 mg Cu/L or more, and its associated toxicity was primarily caused by …

Long-Term Performance Of Passive Materials For Removal Of Ozone From Indoor Air, C. J. Cros, Glenn C. Morrison, J. A. Siegel, R. L. Corsi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The health effects associated with exposure to ozone range from respiratory irritation to increased mortality. in this paper, we explore the use of three green building materials and an activated carbon (AC) mat that remove ozone from indoor air. We studied the effects of long-term exposure of these materials to real environments on ozone removal capability and pre- and post-ozonation emissions. a field study was completed over a 6-month period, and laboratory testing was intermittently conducted on material samples retrieved from the field. the results show sustained ozone removal for all materials except recycled carpet, with greatest ozone deposition velocity …

An Improved Prediction Model For Spacecraft Damage Following Orbital Debris Impact, Joel E. Williamsen, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper offers a new set of 'generic', data-Based hole size and crank length prediction models for spherical orbital debris particles impacting multi-plate targets at velocities up to ~12 km/s. the equations are applicable to a wide variety of spacecraft target configurations, but are limited to hole sizes above, but relatively near, the ballistic limit of the impacting particles. Additional work is underway to expand these models to diameters farther above the ballistic limit for the described shield types.

Breaking Internal Waves On A Shelf Slope Using Numerical Simulations, Subhas K. Venayagamoorthy, Oliver B. Fringer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The subject of internal waves interacting with bottom topographic features in the ocean has received much attention in the past few decades. This heightened interest is mainly due to a conjecture that breaking internal waves at boundaries can be a significant source of turbulence, leading to mixing and transport in the ocean. In this paper, we present results from high-resolution three-dimensional numerical simulations of an internal wave interacting with a shelf break in a linearly stratified fluid in order to highlight the instabilities that contribute to wave breaking over topography. The results show the development of a nonlinear internal bolus …

Life Cycle Cost Analysis Under Ireland's Capital Works Management Framework, Dermot Kehily, Alan Hore

Conference papers

The Capital Works Management Framework (CWMF) is a structure that has been developed to deliver the Irish government’s objectives in relation to public sector construction procurement reform. This research provides practical guidance and assistance for construction cost professionals in carrying out Whole Life Cycle Cost Analysis (WLCCA) and producing Life Cycle Cost Models(LCCMs) under the CWMF. The research outlines how LCCA calculations can be carried out for cost planning purposes and recommends a standard methodology for presenting LCCMs under the CWMF. The CWMF states that Whole Life Costs (WLC) are an important consideration throughout the design process and should be …

2:1 The Paper Tube Project, Noel Brady

Articles

Review of applied technological solution to rapid building techniques using paper tube and analogous materials to create space enclosing geodesic systems.

A Directionally Tunable But Frequency-Invariant Beamformer On An Acoustic Velocity-Sensor Triad To Enhance Speech Perception, Yue Ivan Wu, Kainam Thomas Wong, Xin Yuan, Siu-Kit Lau, Shiu-Keung Tang

Durham School of Architectural Engineering and Construction: Faculty Publications

Herein investigated are computationally simple microphone-array beamformers that are independent of the frequency-spectra of all signals, all interference, and all noises. These beamformers allow the listener to tune the desired azimuth-elevation “look direction.” No prior information is needed of the interference. These beamformers deploy a physically compact triad of three collocated but orthogonally oriented velocity sensors. These proposed schemes’ efficacy is verified by a jury test, using simulated data constructed with Mandarin Chinese (a.k.a. Putonghua) speech samples. For example, a desired speech signal, originally at a very adverse signal-to-interference-and-noise power ratio (SINR) of -30 dB, may be processed to become …

Shake Table Testing Of A Utility-Scale Wind Turbine, Ian Prowell, Chia Ming Uang, Ahmed Elgamal, J. Enrique Luco, Lanhui Guo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Shake table tests were undertaken on a full-scale wind turbine (65-kW rated power, 22.6-m hub height, and 16-m rotor diameter) using the Network for Earthquake Engineering Simulation Large High Performance Outdoor Shake Table at the University of California, San Diego. Structural response characteristics and modal parameters are presented for base shaking imparted in two configurations, both parallel (configuration 1) and perpendicular (configuration 2) to the axis of rotation of the rotor. Results are summarized for a series of progressively stronger motions imparted in configuration 1, with analysis identifying damage sources leading to an overall loss in stiffness. Two sources of …

Application Of Drum-Buffer-Rope Methodology In Scheduling Of Healthcare System, Arefeh Mohammadi, Emmanuel S. Eneyo

Durham School of Architectural Engineering and Construction: Faculty Publications

Theory of constraints (TOC) is a management philosophy that seeks to increase throughput (efficiency or performance) of the system by identifying those processes that are constraining the system bottlenecks. There have been very few profound studies of TOC in health care systems. In order to fill this gap, this study was conducted to determine how healthcare systems are utilizing components of TOC to schedule operations and what results are being obtained. This is done by using a patient flow model for a radiotherapy section of a hospital. The drum-buffer-rope (DBR) was used as the methodology for scheduling this flow. Successful …

Teaching Sustainable Design Using Bim And Project-Based Energy Simulations, Zhigang Shen, Wayne Jensen, Tim Wentz, Bruce Fischer

Durham School of Architectural Engineering and Construction: Faculty Publications

The cross-disciplinary nature of energy-efficient building design has created many challenges for architecture, engineering and construction instructors. One of the technical challenges in teaching sustainable building design is enabling students to quantitatively understand how different building designs affect a building’s energy performance. Concept based instructional methods fall short in evaluating the impact of different design choices on a buildings’ energy consumption. Building Information Modeling (BIM) with energy performance software provides a feasible tool to evaluate building design parameters. One notable advantage of this tool is its ability to couple 3D visualization of the structure with energy performance analysis without requiring …

An Adaptive Utility Interactive Photovoltaic System Based On A Flexible Switch Matrix To Optimize Performance In Real-Time, Mahmoud Alahmad, Mohamed Amer Chaaban, Siu Kit Lau, Jonathan Shi, Jill Neal

Durham School of Architectural Engineering and Construction: Faculty Publications

Reconfigurable architectures are of great interest to system designers to improve the system’s operation and efficiency. In this paper, we propose an adaptive utility interactive photovoltaic (PV) system based on a novel Flexible Switch array Matrix topology. This proposed system maximizes the generated power in real-time in response to operational conditions such as shading, soiling, mismatches, and module failure among others. The proposed system is a compromise in the utilization of power conditioning equipment to maximize energy capture and system efficiency. Simulation results demonstrate an average 13% improvement in efficiency when compared with the central inverter topology performance. A prototype …

Effects Of Roof Pitch On Air Flow And Heating Load Of Sealed And Vented Attics For Gable-Roof Residential Buildings, Shimin Wang, Zhigang Shen

Durham School of Architectural Engineering and Construction: Faculty Publications

Pitch value is an important consideration in residential gable roof design and construction. However, how roof pitch, coupled with air flows in attic space, affects the energy performance of building attics has been barely investigated. In this paper, a 2D unsteady computational fluid dynamics (CFD) model is employed to investigate the effects of roof pitch on air flow and heating load of both sealed and vented attics for gable-roof residential buildings. The simulation results show that air flow in the sealed attics is steady and asymmetric, while that in the vented attics is a combination of an essentially symmetric base …

Effects Of Inclusion Shapes Within Rigid Porous Materials On Acoustic Performance, Hyun Hong, Siu-Kit Lau

Durham School of Architectural Engineering and Construction: Faculty Publications

The present study investigates the influence of various shapes of inclusions having same volume embedded in a porous rigid material. Previous studies showed improvement of the broadband sound absorption with particular shapes of inclusions. However, different volumes of the inclusions have been considered; therefore, the bulk densities are not the same for comparison. The present study extends the investigations of inclusions in porous materials with same volume (or bulk density) to eliminate the influence by the change of bulk density. The effects of shape will be discussed. Finite element modeling will be used for this study. Total four different shapes: …

Impacts Of Ventilation Ratio And Vent Balance On Cooling Load And Air Flow Of Naturally Ventilated Attics, Shimin Wang, Zhigang Shen

Durham School of Architectural Engineering and Construction: Faculty Publications

The impacts of ventilation ratio and vent balance on cooling load and air flow of naturally ventilated attics are studied in this paper using an unsteady computational fluid dynamics (CFD) model. Buoyancy-driven turbulent ventilations in attics of gable-roof residential buildings are simulated for typical summer conditions. Ventilation ratios from 1/400 to 1/25 combined with both balanced and unbalanced vent configurations are investigated. The modeling results show that the air flows in the attics are steady and exhibit a general streamline pattern that is qualitatively insensitive to the variations in ventilation ratio and vent configuration. The predicted temperature fields are characterized …

The Impact Of Roof Pitch And Ceiling Insulation On Cooling Load Of Naturally-Ventilated Attics, Shimin Wang, Zhigang Shen, Linxia Gu

Durham School of Architectural Engineering and Construction: Faculty Publications

A 2D unsteady computational fluid dynamics (CFD) model is employed to simulate buoyancy-driven turbulent ventilation in attics with different pitch values and ceiling insulation levels under summer conditions. The impacts of roof pitch and ceiling insulation on the cooling load of gable-roof residential buildings are investigated based on the simulation of turbulent air flow and natural convection heat transfer in attic spaces with roof pitches from 3/12 to 18/12 combined with ceiling insulation levels from R-1.2 to R-40. The modeling results show that the air flows in the attics are steady and exhibit a general streamline pattern that is qualitatively …

Development And Evaluation Of A Simplified Modeling Approach For Hydraulic Systems, Yuebin Yu, Vivian Loftness, Daihong Yu, Yan Lu, Volker Hartkopf

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents how a hydraulic system can be properly modeled for hydraulic balancing, knowledge of flow distribution, coupled simulation, and evaluation of control, etc. It focuses on water-based heating and cooling systems, which generally have high energy efficiency in design but could perform poorly in reality due to the undersensing condition and strong thermal-hydraulic coupling. The study introduces the motivation, presents the simplified modeling methodology, and illustrates the model and simulating structure. A preliminary evaluation of the method is conducted with two simple simulations. The proposed “node-branch-state” modeling approach could be easily modified, expanded and integrated into a detailed …

Ann Based Load Identification And Forecasting System For The Built Environment, Hosen Hasna

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

"Phantom Loads" cause energy waste in homes and the built environment as a whole. Consumers spend more than $3 billion a year on "Phantom Load" in the United States alone. The goal of this work is to conserve energy by increasing consumer awareness on their energy usage and appropriate tools which in turn will be reducing and /or eliminating phantom loads and mismanagement of the load in the built environment. A further goal is to improve upon existing power distribution systems in the built environment with limited hardware additions to increase energy conservation. This work investigates remote identification of load …

Modeling Unbound Granular Materials Under Complex Stress Paths, Cheng Chen, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Developing reliable and versatile constitutive models for geomaterials has been challenging tasks for nonlinear finite element analysis of geotechnical engineering systems. the fuzzy set plasticity theory has been developed to account for the nonlinear soil stress-strain response under complex stress paths. the theory in many ways resembles the bounding surface plasticity, where the plastic modulus is a function of the distance between the current and image stress states in the stress space. based on the concept of fuzzy set theory in mathematics, a membership function whose value ranges from 1 and 0 is introduced in the Fuzzy Set Plasticity Theory …

Characterization Of Crushed Rock-Concrete Interface Behavior Through The Parallel Gradation Technique, Domenica Cambio, Xin Kang, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The response of a soil-structure system subjected to monotonic or cyclic loading is influenced significantly by the mechanical behavior of soil-structure interface. in this paper, the friction characteristics of the crushed rock-concrete interface and the role of the crushed rock deformability were examined through a series of monotonic and cyclic direct shear tests. the physical modeling technique of parallel gradation was adopted where two parallel gradation curves of the crushed rocks were prepared and used in the tests. the tests were carried out in dry condition and with two initial void ratios representing both loose and dense states. Two concrete …

Measuring Global Response Of A Wind Turbine To Simulated Earthquake Shaking Assisted By Point Tracking Videogrammetry, Ian Prowell, Tim Schmidt, Ahmed Elgamal, Chia Ming Uang, Hal Romanowitz, J. Edward Duggan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Experiments investigating earthquake response of structures traditionally use conventional wired instruments such as strain gauges, displacement transducers, and accelerometers deployed at key areas of interest throughout structure. for wind turbines the rotor is one of these key areas, but due to rotation it is not possible to use wired instruments without a special slip ring. in a recent experiment conducted using the Network for Earthquake Engineering Simulation (NEES) Large High Performance Shake Table (LHPOST) at the University of California, San Diego (UCSD) the global response of a full scale 65-kW turbine (22 m hub height) was monitored using a novel …

Application Of Threshold Concepts To Improve A Design-Focused Course In Transportation Engineering, Dan Cernusca, Ghulam Bham

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Design is an integral part of engineering courses. to address its associated problems, however, is a challenging task in instruction because of design's open-endedness and complexity. in this study, two theoretical models were implemented in an introductory transportation engineering course to address the challenges associated with design of a highway. First, the theoretical framework proposed by the threshold concepts model was used to identify a candidate concept for the instructional redesign process. Two major characteristics of threshold concepts, integrativity and transformativity, were used to identify horizontal alignment as a candidate concept for the highway design process. Second, concept mapping was …

Evaluation Of Pre-Consolidation Stress Determination Methods, Omar Conte, Stephanie Rust, Louis Ge, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Pre-Consolidation Pressure Provides Valuable Information About Soil Behavior And, Specifically, Settlement under an Induced Load. Soil is Expected to Have Less Settlement Before its Pre-Consolidation Pressure and Much More Settlement after that Point. the Pre-Consolidation Pressure and the Compressibility of the Soil Can Be Determined from the Results of a One-Dimensional Consolidation Test. Different Methods Have Been Developed to Obtain the Accurate Pre-Consolidation Pressure from One Dimensional Consolidation Test Data. This Paper Presents and Discusses the Results of the One-Dimensional Consolidation Test Data from an Extensive Testing Program. the Test Specimens Used Were Obtained from Multiple Borehole Locations and Were …

Life Cycle Costing Template (Excel), Dermot Kehily

Reports

No abstract provided.