Architecture Commons^™

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 …

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 …

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 …

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 …

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 …

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 …

Developing Dendrifrom Facades Using Flow Nets As A Design Aid, Jonas H. Houston

Master's Theses

This thesis highlights a method of arriving at form that minimizes the need for high end technology and complex mathematical models, yet has structural principles of load flow at the highlighted methods core. Similar to how graphical statics assisted earlier architects and engineers to arrive at form by relating form and forces, this thesis suggests a method of form finding that relates the flow of stresses within solid masses to possible load-bearing façades. Looking to nature, where an abundance of efficient structural solutions can be found, this thesis focuses on a tree-like structural form called the dendriform. In doing so, …

Fenestration Studies On Building Energy Using The Facade Evaluation Facility, Wendell Cocina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The project was developed to assess several types of facades and their influence on building energy, mainly focused on windows and other building fenestrations. Requirements for the facility are stated in this paper alongside corresponding solutions. The facility is designed to represent a section of a building façade. Experimenting on a wide range of fenestrations including windows with integrated PV elements was the primary prerequisite. The option of removable façade configurations was used and allowed testing specimens to be changed effortlessly. Instrumentation and data acquisition are discussed including calibration and uncertainty analysis. Investigation of the air conditioning unit was concluded …

Technologies Enabling Sustainability In The Built Environment, Mahmoud Alahmad, Muhammad Zulfiqar, Hosen Hasna Hh, Timothy Wisnieski, Nasser Aljuhaishi, Hamid Sharif

Durham School of Architectural Engineering and Construction: Faculty Publications

Energy conservation is among society’s greatest challenges, and the built environment has a concentrated impact on our natural environment, economy, and health. Fundamental understandings of how energy is consumed, monitored, and controlled are key prerequisites for an energy conservation process. This paper evaluates the effectiveness of real-time energy monitors (RTM) to influence behavior change in residential consumers. A methodology for remote identification of load types along the electrical circuitry where they (load) are being consumed is also presented. The load type and status (on, off, standby) are determined both remotely and in a non-intrusive manner using Non-Intrusive Load Monitoring Methods. …

Verification And Expansion Of Single-Degree-Of-Freedom Transformation Factors For Beams Using A Multi-Degree-Of-Freedom Non-Linear Numerical Analysis Method, Takayuki Yokoyama

Master's Theses

The single-degree-of-freedom (SDOF) transformation factors as tabulated in John Biggs’ textbook (Biggs 1964) are accepted as the equivalent factors for simplifying and analyzing a component's response to blast. The study validates the stiffness and mass transformation factors through multi-degree-of-freedom (MDOF) numerical methods. After validating the transformation factors, the MDOF numerical method is used to create new stiffness and mass transformation factors for loading cases not already included in Biggs’ textbook.

The validated factors, as well as the newly developed factors are used in SDOF analyses. The deflections from the SDOF responses accurately predict the MDOF responses as long as the …

Investigating Pipeline–Soil Interaction Under Axial–Lateral Relative Movements In Sand, Nasser Daiyan, Shawn Kenny, Ryan Phillips, Radu Popescu

Architectural Engineering

This paper presents results from an experimental and numerical study on the axial–lateral interaction of pipes with dense sand. A series of centrifuge tests were conducted, with a rigid pipeline displaced in the horizontal plane in a cohesionless test bed. The relative pipe–soil interaction included axial, lateral, and oblique loading events. A three-dimensional continuum finite element model was developed using ABAQUS/Standard (Hibbitt et al. 2005) software. The numerical model was calibrated against experimental results. A parametric study was conducted, using the calibrated finite element model to extend the investigations. The ultimate axial and lateral soil loading was found …

Mixing Numbers And Letters: Collaboration Between Engineering And English To Improve Graduate Student Work, Craig Baltimore, Deborah Wilhelm, Mary Forte, Pamalee Brady

Architectural Engineering

This paper will describe the issues and process of developing an introductory course in graduate writing and communication skills in conjunction with the industry of professional consulting engineering. The course was developed through a collaboration of English and engineering faculty and the collaboration is maintained in the teaching of the course. Innovative techniques incorporated into the course development include a four-pronged approach: 1) use of best practices for Writing in the Disciplines; 2) development of and focus on a multi-faceted collaborative model (Engineering and English, university and industry, students and faculty, industry and students); 3) team-teaching by engineering and English …

The Bridge Newsletter Winter 2011, Missouri University Of Science And Technology

The Bridge Newsletter

-Living intentionally: Meet the Oerthers
-Making a lasting impact
-Phytoforensics
-The simple things of life

Monitoring The Early-Age Hydration Of Self-Compacting Concrete Using Ultrasonic P-Wave Transmission And Isothermal Calorimetry, Bram Desmet, Kelly Chrysanthe Atitung, Miguel Angel Abril Sanchez, John Vantomme, Dimitri Feys, Nicolas Robeyst, Katrien Audenaert, Geert De Schutter, Veerle Boel, Gert Heirman, Özlem Cizer, Lucie Vandewalle, Dionys Van Gemert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Early-Age Hydration (B48 H) of a Series of Self-Compacting Concretes and Corresponding Mortars and One Traditionally Vibrated Concrete and Mortar is Monitored in a Continuous Way using Ultrasonic Testing and Isothermal Calorimetry. the Mixtures Differ in Type of Mineral Addition, Superplasticizer, Cement, Cement-To-Powder Ratio and Water-To-Powder Ratio. the Influence of These Different Mixture Compositions on the Kinetics of the Hydration during the First Days of the Hydration is Characterized by the Heat Production Rate Q and the Evolution of the P-Wave Velocity, which is a Consequence of the Microstructural Changes. the Variations in the Acceleration Caused by Mineral Additions …

Phytoscreening For Chlorinated Solvents Using Rapid In Vitro Spme Sampling: Application To Urban Plume In Verl, Germany, Matt A. Limmer, Jean Christophe Balouet, Frank Karg, Don A. Vroblesky, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rapid Detection and Delineation of Contaminants in Urban Settings is Critically Important in Protecting Human Health. Cores from Trees Growing above a Plume of Contaminated Groundwater in Verl, Germany, Were Collected in 1 Day, with Subsequent Analysis and Plume Mapping Completed over Several Days. Solid-Phase Microextraction (SPME) Analysis Was Applied to Detect Tetrachloroethene (PCE) and Trichloroethene (TCE) to Below Nanogram/liter Levels in the Transpiration Stream of the Trees. the Tree Core Concentrations Showed a Clear Areal Correlation to the Distribution of PCE and TCE in the Groundwater. Concentrations in Tree Cores Were Lower Than the Underlying Groundwater, as Anticipated; However, …

Direct Shear Tests On Jsc-1a Lunar Regolith Simulant, Masafumi Iai, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A series of direct shear tests were conducted on the JSC-1A lunar regolith simulant in a 101.6-mm- (4-in.-) diameter container. the direct shear test provides a unique mode of failure that aids the development of excavation tools for the Moon. Relative density and normal load were varied to study the strength behavior of such granular material at peak and critical state conditions. the values of the internal friction angle ranged from 30 to 70. a relationship between the internal friction angle of the direct shear and the published triaxial compression test results is presented. Additionally, the measured dilatancy angle is …

Longitudinal Evaluation Of A Gis Laboratory In A Transportation Engineering Course, Ghulam H. Bham, Dan Cernusca, Ronaldo Luna, Uday R.R. Manepalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper focuses on the potential impact of student-centered feedback for enhancing the learning experience of civil engineering students that used a geographic information system (GIS) based tutorial in a transportation engineering course. the tutorial was implemented in a laboratory environment developed as a self-guided activity supported by a web-Based learning system. the formative research proposed in this study includes a series of four successive implementations of this laboratory. Students' performance, beliefs, and perceptions were monitored by using a mixed methods design approach and weaknesses identified from early implementations were addressed before the next implementation of the laboratory activity. the …

Remote Sensing Of Soil Moisture Using Airborne Hyperspectral Data, Michael Finn, Mark Lewis, David Bosch, Mario Giraldo, Kristina Yamamoto, Dana Sullivan, Russell Kincaid, Ronaldo Luna, Gopala Allam, Craig Kvien, Michael Williams

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Landscape assessment of soil moisture is critical to understanding the hydrological cycle at the regional scale and in broad-scale studies of biophysical processes affected by global climate changes in temperature and precipitation. Traditional efforts to measure soil moisture have been principally restricted to in situ measurements, so remote sensing techniques are often employed. Hyperspectral sensors with finer spatial resolution and narrow band widths may offer an alternative to traditional multispectral analysis of soil moisture, particularly in landscapes with high spatial heterogeneity. This preliminary research evaluates the ability of remotely sensed hyperspectral data to quantify soil moisture for the Little River …

Correction Factors For An Analytical Method Of Pile Foundation Response Subjected To Horizontal Dynamic Vibrations, Domenica Cambio, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In pile foundation response due to horizontal vibration, it is known that the original Novak's method overestimates the dominant frequency and underestimates the dominant amplitude of pile head responses. It is found that reducing the pile-foundation system stiffness and damping coefficients would lead to a smaller dominant frequency and higher dominant amplitude, respectively. the objective of this paper is to evaluate and determine appropriate correction factors for stiffness and damping coefficients for the analytical model developed by Novak and El-Sharnouby (1983) to improve the theoretical predictions of pile foundations subjected to dynamic forces. the reduction factors were determined by continuously …

Modern Protection Systems To Prevent Corrosion Of Structural Steel Elements Due To Deicing And Roadway Salts, John J. Myers, Wei Zheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of innovative polymeric coatings, polyurea and Poly aspartic polyurea, to protect structural steel from corrosion was investigated through standard laboratory tests. the coating evaluation tests included salt fog test, QUV weathering test, adhesion test, and freeze-thaw stability test. These tests were used to assess the long-term performance of coating technologies compared to the conventional polyurethane type coatings, i.e. coating systems with inorganic zinc primer, epoxy intermediate coat and polyurethane topcoat. This paper presents part of results in the aforementioned evaluation tests. the results illustrate that Poly aspartic coating systems are very promising for corrosion mitigation and can provide …

Accelerated Construction For Pedestrian Bridges: A Comparison Between High Strength Concrete (Hsc) And High-Strength Self Consolidating Concrete (Hs-Scc), John J. Myers, Kurt Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High-strength concrete (HSC) and glass fiber reinforced polymer (GFRP) bars are materials utilized in bridge construction to lower cost, reduce construction time, and increase service life of bridge structures. Recently, high-strength self-consolidating concrete (HS-SCC), a highly flowable concrete that does not require vibration, has been developed as a viable alternative to HSC for use in situations with congested steel or a need for rapid construction. Coupling HS-SCC with GFRP bars could create durable structures built rapidly. Several performance related issues remain to be investigated such as the behavior of prestress loss, shear, creep, shrinkage, thermal gradients, mechanical property development, time …

Earthquake-Induced Deformation Analysis Of A Bridge Approach Embankment In Missouri, W. Liu, Ronaldo Luna, Richard Wesley Stephenson, S. Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Earthquake-Induced Deformations for a Bridge Approach Earth Embankment Are Predicted using a Calibrated Numerical Model. the Constitutive Soil Model is a Modified Hyperbolic Model that Uses Masing Rules and Incremental Pore Pressure Relations. the Model Was Calibrated using Both Laboratory and Field Data. a Shaking Table Physical Model Was Used to Verify the Numerical Simulation. Additionally, the Upper San Fernando Dam Was Modeled to Reproduce the Deformations in the 1971 Earthquake. the Subsurface and Embankment Soil Conditions Were Characterized using Field and Laboratory Methods. the Model Developed Was Used to Predict the Earthquake-Induced Deformations of an Approach Embankment to Bridge …

Influence Of Geotechnical Dataset On The Range Of Influence Of Undrained Shear Strength, Site Onyejekwe, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The knowledge of the spatial variability of geotechnical parameters, which can be described statistically by the mean, the variance, and the scale of fluctuation, is important in reliability-Based design. of particular importance is the scale of fluctuation. It can be used to compute the variance reduction factor, a factor of spatial averaging of geotechnical properties to reduce their point variance. the most prevalent method of determining the scale of fluctuation uses datasets whose data points are at close and regular intervals, e.g. measurements from cone penetrometer soundings. Another method, when continuous measurements are not available, uses datasets that are widely …

Special Issue On The 6th International Phytotechnologies Conference, St. Louis, Missouri, 2009: Conference Review, Joel G. (Gerard) Burken, Jason C. White

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Phytoforensics, Dendrochemistry, And Phytoscreening: New Green Tools For Delineating Contaminants From Past And Present, Joel Gerard Burken, Don A. Vroblesky, Jean Christophe Balouet

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As Plants Evolved to Be Extremely Proficient in Mass Transfer with their Surroundings and Survive as Earth's Dominant Biomass, They Also Accumulate and Store Some Contaminants from Surroundings, Acting as Passive Samplers. Novel Applications and Analytical Methods Have Been Utilized to Gain Information About a Wide Range of Contaminants in the Biosphere Soil, Water, and Air, with Information Available on Both Past (Dendrochemistry) and Present (Phytoscreening). Collectively These Sampling Approaches Provide Rapid, Cheap, Ecologically Friendly, and overall "Green" Tools Termed "Phytoforensics". © 2011 American Chemical Society.

Arsenic Accumulation In Rice Grains: Effects Of Cultivars And Water Management Practices, Bin Hua, Wengui Yan, Jianmin Wang, Baolin Deng, John Yang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Arsenic (As) accumulation in rice grains is a threat to human health and marketability of rice products. in an effort to minimize as uptake by rice grains, field experiments were conducted to investigate as accumulation in rice grains of three cultivars in monosodium methane arsonate-treated soil under saturated and flooded water management practices. Results indicated that as concentrations in rice grains were cultivar-dependent and influenced by water management. Soil flooding would substantially enhance the as accumulation with a great variation among cultivars. Extractable as in the soil was positively correlated with sodium dithionite-sodium citrate-sodium bicarbonate solution-extractable Fe, suggesting a strong …

Implementation Of Integrated Commissioning, Retrofits, And Control Optimization Process In A Small Commercial Building, Xiangnan Shi

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

A large amount of the primary energy consumed in the US is derived from the built environment followed by energy consumed in the transportation and industrial sectors. Consequently, improving the energy efficiency of buildings is an important part of ensuring a more sustainable world for future generations. Of the various techniques employed to improve the energy efficiency of buildings, commissioning and retrofits continue to be the most widely applied solutions. Control optimization, mainly imbedded with continuous commissioning so far, is not applied as widely. Even though there are currently a few applications that integrate all three techniques, no comparison has …

Inhabiting The Periphery: A Dialogue Between Individual And Site, Robert Oliver Kown

Masters Theses

What is a periphery? We can think about this word in more than one way. First off, peripheries are places that exist as spatial conditions in cities, They indicate edges and places that have been left behind. Spaces that have lost their meaning. But in this thesis I will use the word in another way as well. What does the periphery mean for us today? What are those parts of our lives that have been marginalized, and how can we begin to reclaim what has been lost? It is the aim of this thesis to address these issues of the …

Optimized Control Strategies For A Typical Water Loop Heat Pump System, Xu Lian

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

Water Loop Heat Pump (WLHP) System has been widely utilized in the Heating, Ventilating and Air Conditioning (HVAC) industry for several decades. There is no doubt about the energy saving potential of this type of system from the design and construction perspective. However, there are still many unsolved problems, such as high loop pump energy consumption, low heat pump efficiency and high electricity cost due to improper operation, although the system design intension was to save energy. Thus, how to control the WSHP to realize its energy-efficient value is an innovative but practical topic on which this thesis will focus. …