Architectural Engineering Commons^™

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 …

Revisions To Tilt-Up Concrete Building Design: The Backstory Behind Changes Encompassed In 2009 International Building Code, John W. Lawson

Architectural Engineering

The 2009 International Building Code (IBC) has in its scope some significant revisions that greatly affect the design of tilt-up concrete buildings, but to the lay engineer it appears that some of these provisions are a step backwards. With the IBC’s referencing standards including ACI 318-08 (concrete) and the 2008 NDS SDPWS (timber), these documents have significant changes that become effective with the adoption of the IBC. We as engineers expect building codes to advance the state of the art with each successive edition. The 2009 International Building Code (IBC) and the Building Code Requirements for Structural Concrete (ACI 318-08) …

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 …

Finite-Element Limit Analysis Of The Tucker High School Gymnasium Roof Failure, Peter T. Laursen, Edmond P. Saliklis

Architectural Engineering

The Randolph Tucker High School gymnasium roof failure of 1970 has received much scholarly attention. This study will provide a conclusion to a large body of previously published works by means of limit state analysis of the roof failure using state of the art parametric finite-element modeling. Parametric modeling within a general purpose finite-element analysis program allows for extremely rapid changes to the model because key terms are objects or parameters that can be adjusted internally by the program, rather than laboriously entered by the user. The failure of the roof was investigated by means of a limit state analysis, …

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

Spectral Amplification Of Seismic Motion Travelling Through Natural Sand Deposits, Pradipta Chakrabortty, Radu Popescu

Architectural Engineering

Guidelines for seismic spectral amplification are provided in current building codes based on soil strength/stiffness by means of seismic site class. However, current codes do not make a difference between fully saturated and unsaturated soil deposits and do not account for effects of soil heterogeneity on seismic amplification. This study investigates the effect of natural small scale soil heterogeneity and degree of saturation on spectral amplification by means of transient nonlinear finite element analyses. Only cohesionless soil (sand) is considered in this study. The effects of presence of a structure are also studied for soils with two different relative densities. …

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 …

From The Personal To The Communal - Support For An Evolutionary Urban System, Noel Brady

Conference papers

A short discussion towards a model for the future of urban and interurban development. From the personal tot he communal argues for a futurist city that is an organic physiological time filled environment.

Ua61/3 Wku Nursing & Physical Therapy - The Medical Center - Wku Health Sciences Complex, Wku Health & Human Services

WKU Administration Documents

Fundraising brochure regarding The Medical Center – WKU Health Sciences Complex constructed from 2012 through 2014. Features architectural renderings of each floor.

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 …

Topological Theory In Bioconstructivism, John Shannon Hendrix

Architecture, Art, and Historic Preservation Faculty Publications

In the essay “Landscapes of Change: Boccioni’s Stati d’animo as a General Theory of Models,” in Assemblage 19, 1992, Sanford Kwinter proposed a number of theoretical models which could be applied to computer-generated forms in Bioconstructivism. These included topological theory, epigenesis, the epigenetic landscape, morphogenesis, catastrophe and catastrophe theory. Topological theory entails transformational events or deformations in nature which introduce discontinuities into the evolution of a system. Epigenesis entails the generation of smooth landscapes, in waves or the surface of the earth, for example, formed by complex underlying topological interactions. The epigenetic landscape is the smooth forms of relief which …

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 …

Seismic Design Of Timber Panelized Roof Structures, John W. Lawson

Architectural Engineering

No abstract provided.

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 …

Wind Design Of Timber Panelized Roof Structures, Brian Vandenburgh, John W. Lawson

Architectural Engineering

No abstract provided.

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 …

Numerical Simulation Of Centrifuge Tests On Homogeneous And Heterogeneous Soil Models, Pradipta Chakrabortty, Radu Popescu

Architectural Engineering

Soil liquefaction is a major cause of seismic damage in cohessionless soil during earthquakes. From past numerical and experimental research it has been observed that more excess pore water pressure (EPWP) is generated during earthquakes in a heterogeneous soil deposit than in the corresponding homogeneous soil with relative density equal to the average relative density of the heterogeneous soil. This interesting phenomenon is investigated here, by numerically simulating centrifuge experiments of seismically induced soil liquefaction using the finite element code DYNAFLOW. Two centrifuge tests are numerically simulated here: one in homogeneous soil and another in heterogeneous soil. Recorded experimental results …