Architecture Commons^™

Fm, Risk And Climate Change Adaptation, Keith Jones, Mark Mulville, Adele Brooks

Conference papers

Improving the sustainability of built assets in the light of uncertain futures is a major challenge facing the Facilities Management profession. A changing climate poses significant challenges to the performance of built assets in-use and could potentially render many built assets prematurely obsolete. How business clients plan for such changes formed the focus of a research project undertaken by the authors. This paper presents the findings of a 12 month Action Research project that sought to identify the impact of future climate change on the performance of a new £75m education building over the first 60 years of operation. The …

Wind Loading On Trees Integrated With A Building Envelope, Aly Mousaad Aly, Alberto Zasso, Girma Bitsuamlak, Alberto Nicola Longarini, Arindam Gam Chowdhury

Faculty Publications

With the sustainability movement, vegetated building envelopes are gaining more popularity. This requires special wind effect investigations, both from sustainability and resiliency perspectives. The current paper focuses on wind load estimation on small- and full-scale trees used as part of green roofs and balconies. Small-scale wind load assessment was carried out using wind tunnel testing in a global-effect study to understand the interference effects from surrounding structures. Full-scale trees were investigated at a large open-jet facility in a local-effect study to investigate the wind-tree interaction. The effect of Reynolds number combined with shape change on the overall loads measured at …

Effect Of Fly Ash On Growth Of Mustard And Corn, Cailie Carlile, Snehalata Nadiger, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fly Ash is Generated as a By-Product of Coal Combustion and Contains Many Nutrients, Such as Ca, K, Na, Mg, and S, as Well as Toxic Metals Such as As, B, Cd, Cr, Hg, and Pb. for This Project, the Goal is to Optimize a Phytoremediation Technique to Stabilize the Toxic Metals and Produce Biomass Which Could Have Benefit for Example as Biofuel. the Hypothesis Was that Different Amendments Would Improve the Water Holding Properties of the Ash and Reduce Metals Availability and Toxicity. Flyash Was Combined with Leaf Mulch (1%, 3%, 5%, 10%, 20%), Wood Mulch (1%, 3%, 5%, …

Extension Of The Reiner-Riwlin Equation To Determine Modified Bingham Parameters Measured In Coaxial Cylinders Rheometers, Dimitri Feys, Jon E. Wallevik, Ammar Yahia, Kamal H. Khayat, Olafur H. Wallevik

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Determination of the Exact Rheological Properties, in Fundamental Units, of Cementitious Materials Has Become Gradually a Necessary Step in the Domain of Concrete Science. Several Types of Rheometers and their Corresponding Transformation Equations Are Described in the Literature. in This Paper, the Reiner-Riwlin Transformation Equation, Valid for Coaxial Cylinders Rheometers, is Developed for the Modified Bingham Model, which is an Extension of the Bingham Model with a Second Order Term in the Shear Rate. the Established Transformation is Shown to Be Compatible with the Reiner-Riwlin Equation for the Bingham and Herschel-Bulkley Models. its Validation is Further Proven by Means …

Use Of Vacuum For The Stabilization Of Dry Sand Slopes, B. Bate, Limin Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Vacuum is proposed as a means for rescuing soil slopes showing signs of impending failure. Two aspects associated with the proposed method were studied: namely, the theory of airflow through dry soils and the effectiveness of vacuum for enhancing the stability of soil slopes. A model test device was developed, and two series of tests were carried out using this device. One was a series of tests on pore-air pressure distributions in dry sand slopes, and the second series involved dry sand slope stability tests. The results revealed that a vacuum (negative pore-air pressure) even as small as 20.4 kPa …

Performance-Based Seismic Design Of Unbonded Precast Post-Tensioned Concrete Filled Gfrp Tube Piers, Haitham M. Dawood, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a seismic design procedure for self-centering precast post-tensioned bridge piers. The piers presented in this manuscript consisted of concrete filled fiber reinforced polymer (FRP) tubes. A large set of 84 piers with different design parameters were analyzed using finite element models. The backbone curve of each pier was developed and bilinearized. The idealized backbone curves were used to develop a set of empirical equations that were able to reproduce the bilinearized backbone curve of a given pier. Different performance criteria have been proposed for the system according to the intensity and the frequency of occurrence of a …

Spacecraft Module Hole Size And Crack Length Prediction Following A Penetrating Debris Particle Impact, Joel E. Williamsen, William P. Schonberg, Hilary J. Evans

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The process used to calculate and reduce the consequences of meteoroid and orbital debris (MOD) penetrations and their link to catastrophic failure has evolved over time. As the threat of the orbital debris population increased in the 1980s and early 1990s, NASA developed a tool to determine the probability of no catastrophic failure, or PNCF, for the space station and to assess possible changes in station design and/or operations to improve that survivability percentage. PNCF is directly related to the PNP, or probability of no penetration, as calculated by Bumper, the code used by NASA to perform MOD risk assessments. …

Acoustic Tweets And Blogs: Using Social Media In An Undergraduate Acoustics Course, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Each fall, the author teaches an undergraduate architectural acoustics course to around 40 third-year architectural engineering students at the University of Nebraska. Beginning in 2011, a social media component was introduced to explore the use of this technology and how it may supplement the students' learning experience. Students were given an opportunity to receive extra credit by using Twitter and/or blogging about course material using a set hashtag (#AE3300) or through the course website. Results were positive, and the author will discuss pros and cons that she has experienced in adding this social media component. Suggestions for future implementations and …

Some Insights For The Prediction Of Near-Wall Turbulence, Farid Karimpour, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, we revisit the eddy viscosity formulation to highlight a number of important issues that have direct implications for the prediction of near-wall turbulence. For steady wall-bounded turbulent flows, we make the equilibrium assumption between rates of production (P) and dissipation (ε) of turbulent kinetic energy (κ) in the near-wall region to propose that the eddy viscosity should be given by vt ε/S², where S is the mean shear rate. We then argue that the appropriate velocity scale is given by (STL)-1/2 k^1/2 where TL = k ε is the turbulence (decay) time scale. The …

Elec 2110: Elements Of Electrical Engineering—A Peer Review Of Teaching Project Benchmark Portfolio, Mahmoud Alahmad

UNL Faculty Course Portfolios

I have been teaching this class for the last five years. As an introductory course to electrical engineering, there is a lot of material that needs to be covered. All the material is important and relevant, and I try to go in-depth in each topic area. This approach has resulted in overwhelming the students and made them struggle with the course content, application and utilization. As I consider this course for the peer review, I am evaluating the depth of each topic and the opportunity to adjust the approach and method used to introduce new concepts and at the same …

Appropriate Viscous Damping For Nonlinear Time-History Analysis Of Base-Isolated Reinforced Concrete Buildings, Deepak R. Pant, Anil C. Wijeyewickrema, Mohamed A. Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

SUMMARY: There is no consensus at the present time regarding an appropriate approach to model viscous damping in nonlinear time-history analysis of base-isolated buildings because of uncertainties associated with quantification of energy dissipation. Therefore, in this study, the effects of modeling viscous damping on the response of base-isolated reinforced concrete buildings subjected to earthquake ground motions are investigated. The test results of a reduced-scale three-story building previously tested on a shaking table are compared with three-dimensional finite element simulation results. The study is primarily focused on nonlinear direct-integration time-history analysis, where many different approaches of modeling viscous damping, developed within …

Using Architecture Pedagogy To Enhance Engineering Education, Shannon Chance, Mike Murphy, Gavin Duffy, Brian Bowe

Conference papers

Based on evidence, numerous advisory boards and scholars insist engineering education must change (NSB, 2007; McKenna, Froyd, King, Litzinger, & Seymour, 2011) and that hands-on, inquiry-driven, project-based learning pedagogies can enhance STEM education (Boyer & Mitgang, 1996). These pedagogies have formed the core of architectural education since the Renaissance and have been in continuous use since that time. As such, engineering educators can benefit from observing how architecture students learn and understanding how they are taught. Likewise, architecture can benefit from applying the group-based learning strategies employed by engineering teachers who use studentcentered, project-based pedagogies. Trans-disciplinary approaches hold particular merit.

An Experimental Study On Shear Strength Of Chemically-Based Self-Consolidating Concrete, Mahdi Arezoumandi, Jeffery S. Volz

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

An experimental investigation was conducted to compare the shear strength of full-scale beams constructed with chemically based, self-consolidating concrete (SCC) with conventional concrete (CC). This experimental program consisted of 16 rectangular beams (12 without shear reinforcing and 4 with shear reinforcing in the form of stirrups), 8 beams for each mix design. Additionally, three different longitudinal reinforcement ratios were evaluated within the test matrix. The beam specimens were tested under a simply supported four-point condition. The experimental shear strengths of the beams were compared with both the shear provisions of selected standards (U.S., Australia, Canada, Europe, and Japan) and a …

Probability Of Failure For Slopes With Sensitivity Analysis, Michelle Deng, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The significance of random variables on the probability of failure of slopes is generally evaluated by changing a different set of values for each variable and repeating the approach several times to conclude a trend. This method is very straightforward but requires time and computational resources; and it is inefficient especially when the number of random variables is large. This paper presents an analysis approach in which the sensitivity analysis is introduced to quantify the influence of the random variables on the probability of failure for slopes. In this study, the factor of safety of the slope was determined using …

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 …

Scale Of Fluctuation Of Geotechnical Parameters Estimated From Cptu And Laboratory Test Data, Site Onyejekwe, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For a complete probabilistic characterization of a geotechnical parameter, its mean, variance, and the scale of fluctuation have to be known. While the mean and variance can be easily determined, determination of the scale of fluctuation is a little more complex. Knowledge of the scale of fluctuation is important in reliability-based design as it is used in implementing spatial averaging and computing the variance-reduction factor. Published values of scale of fluctuation of geotechnical parameters are based on widely sourced data and hence may not be most appropriate for local situations. Based on 11 CPTu soundings and laboratory test results of …

Effect Of Fly Ash On The Shear Strength Of Concrete Beams Without Shear Reinforcement, Mahdi Arezoumandi, Jeffery S. Volz, Carlos A. Ortega

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The following paper presents the results of an experimental investigation of the shear strength of full-scale reinforced concrete beams constructed with both high-volume fly ash concrete (HVFAC)-concrete with at least 50% of the cement replaced with fly ash-and conventional concrete (CC). This study includes two HVFAC mixes and one CC mix. The two HVFAC mixes are identical except for the amount of Class C fly ash replacement of cement, with one mix replacing 50% of the cement with fly ash and the other replacing 70 %. The test matrix included 18 beams-six for each concrete type-with three different longitudinal reinforcement …

Effect Of High-Volume Fly Ash On Shear Strength Of Concrete Beams, Mahdi Arezoumandi, Jeffery Volz, John Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Every year concrete production exceeds 6.5 billion tons worldwide, nearly 1 ton for every man, woman, and child on the planet. In fact, concrete is used 10 times more than any other building material in the world, primarily because of its incredible versatility, availability, and relatively low cost. Unfortunately, the production of Portland cement - the key ingredient in concrete - generates approximately a pound of carbon dioxide for every pound of cement produced. One method of reducing concrete's carbon footprint is to replace a significant amount of the cement with fly ash, a by-product of coal-burning thermal power stations. …

Hypervelocity Impact Testing Of Multiwall Targets Using Multiple Simultaneously Launched Projectiles, William P. Schonberg, Steve Evans, Michael D. Bjorkman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Multiwall shield designs for spacecraft have been studied extensively in the last four decades as a means of reducing the perforation threat of the near-Earth particulate environment over equivalent single-wall structures. The performance of an impact shield is typically characterized by its ballistic limit equation, which is obtained through high-speed impact tests that typically use spherical projectiles fired in light gas guns. Traditional firings employ only one projectile per launch package. However, some facilities have taken to launching multiple projectiles of different sizes in a single launch package. In light of the significant role played by a ballistic limit equation …

Effect Of Moist Curing And Use Of Lightweight Sand On Characteristics Of High-Performance Concrete, Soo Duck Hwang, Kamal H. Khayat, Dalia Youssef

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Factorial design approach was undertaken to determine the effect of initial moist-curing duration (0 and 6 days) on properties of high-performance concrete (HPC) made with different water-to-cementitious materials ratios (w/cm) of 0.30 and 0.40 and sand substitution rates with lightweight sand (LWS) of 0 and 30 %, by volume. Mechanical properties of HPC are shown to be mainly affected by w/cm and total shrinkage of concrete by the LWS replacement rate and initial moist-curing period. It should be noted that concrete made with 30 % LWS replacement that did not receive any moist-curing exhibited lower shrinkage than moist-cured concrete prepared …

An Experimental Study On Bond Strength Of Reinforcing Steel In High-Volume Fly-Ash Concrete, Trevor J. Looney, Mahdi Arezoumandi, Jeffery S. Volz, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The production of Portland cement-the key ingredient in concrete-generates a significant amount of carbon dioxide. However, because of its incredible versatility, availability, and relatively low cost, concrete is the most consumed manmade material on the planet. One method of reducing concrete's contribution to greenhouse gas emissions is the use of fly ash to replace a significant amount of the cement. an experimental investigation was conducted to compare the bond strength of reinforcing steel in high-volume fly-ash concrete (HVFAC)-concrete with at least 50 % of the cement replaced with fly ash-with conventional concrete (CC). This study investigated two HVFAC mixes [with …

Influencing Factors On The Dynamic Properties Of Organobentonites, Bate Bate, Susan Burns

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The dynamic responses of soils are important engineering properties, especially for soils with high organic contents, because these soils can underlie critical support structures such as highway bridges or levees. Consequently, the initial tangent shear modulus (Gmax), secant shear modulus ratio (G/Gmax), and damping ratio (D) are important parameters in evaluating the dynamic soil behavior for soils subjected to earthquake, wind, waves, traffic, and equipment vibration. in this study, these dynamic properties of organ bentonites were quantified experimentally using resonant column tests. the results from this study were evaluated in terms of the effect of shear strain, organic content, and …

Quantifying The Effect Of Nanoparticles On As(V) Ecotoxicity Exemplified By Nano-Fe2o3 (Magnetic) And Nano-Al2o3, Ji Hu, Demin Wang, Brett E. Forthaus, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Nano-Fe₂O₃ (magnetic) and nano-Al₂O₃ are increasingly used in biomedical fields for cellular labeling and drug delivery, and in the industry as catalysts. However, they may also serve as carriers of toxic contaminants and negatively impact the environment and human health. in the present study, Ceriodaphnia dubia was used to assess the toxicity of these nanoparticles (NPs) with and without the presence of background arsenic(V) (As[V]). the results showed that although these NPs alone did not exhibit significant toxicity in the experimental concentration range, they could significantly enhance the toxicity of As(V). the accumulation of …

Numerical Simulation Of Particle-Driven Gravity Currents, Sangdo An, Pierre Y. Julien, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Particle-driven gravity currents frequently occur in nature, for instance as turbidity currents in reservoirs. They are produced by the buoyant forces between fluids of different density and can introduce sediments and pollutants into water bodies. In this study, the propagation dynamics of gravity currents is investigated using the FLOW-3D computational fluid dynamics code. The performance of the numerical model using two different turbulence closure schemes namely the renormalization group (RNG) k-ε scheme in a Reynold-averaged Navier-Stokes framework (RANS) and the large-eddy simulation (LES) technique using the Smagorinsky scheme, were compared with laboratory experiments. The numerical simulations focus on two different …

Statistical Modelling Of The Coupled Effect Of Mix Design And Rebar Spacing On Restricted Flow Characteristics Of Scc, Yahia Ammar, Khayat H. Kamal, Sayed Mohammed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Self-consolidating concrete (SCC) is designed to exhibit high deformability and stability to maintain homogenous suspension of coarse aggregate particles in the mortar during flow to ensure adequate passing ability of the concrete through restricted areas and the filling of the formwork without any consolidation. Proper deformability and uniform suspension of coarse aggregate particles in the matrix are key parameters to ensure successful casting and adequate in situ performance. the required flow properties of concrete are affected by the rheological properties of the mixture and the characteristics of the cast element, including the level of reinforcement. the mixture proportioning of SCC …

Effect Of Scc Mixture Composition On Thixotropy And Formwork Pressure, A. F. Omran, Kamal H. Khayat, Y. M. Elaguab

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High lateral pressure exerted on formwork systems by self-consolidating concrete (SCC) is one of the hindrances for using such highly flowable concrete in cast-in-place applications. Self-consolidating concrete is a complex system that can be made using a wide range of mixture proportioning and often incorporated various chemical admixtures and supplementary cementitious materials. the investigation of the effect of each material ingredient independently on lateral pressure of SCC is not a simple task. in this study, thixotropy is rather used to assess the effect of various mixture parameters on formwork pressure. Thixotropy is determined by the evaluation of the structural buildup …

Can We Teach Lean Construction Methods In Schools Of Architecture, Gary Graham

Fall 2012 Faculty Showcase

Traditionally, schools of architecture are not great laboratories to explore the collaborative processes and teamwork that are essential to integrated design and delivery practices as exemplified by Lean Construction. The pre-eminence of the “hero-architect” in the design studio is in direct conflict with methods that can reduce risk and improve the efficiency of the design and construction delivery process. Risk? Efficiency? Delivery Process?... not mention Cost Control, Schedule and Constructability, are foreign concepts to the predominant design studio culture.

Integrated practices and integrated project delivery are clearly “hot” topics in the design and construction industry today. They are a response …

Lifecycle Energy Consumption Prediction Of Residential Buildings By Incorporating Longitudinal Uncertainties, Endong Wang, Zhigang Shen

Durham School of Architectural Engineering and Construction: Faculty Publications

Accurate prediction of buildings’ lifecycle energy consumption is a critical part in lifecycle assessment of residential buildings. Longitudinal variations in building conditions, weather conditions and building’s service life can cause significant deviation of the prediction from the real lifecycle energy consumption. The objective is to improve the accuracy of lifecycle energy consumption prediction by properly modelling the longitudinal variations in residential energy consumption model using Markov chain based stochastic approach. A stochastic Markov model considering longitudinal uncertainties in building condition, degree days, and service life is developed: 1) Building’s service life is estimated through Markov deterioration curve derived from actual …

Survey Of Surface Fault Rupture And Structure Interation, Lucy Redmond

Master's Theses

This report aims to raise awareness of the hazards of surface fault rupture and to identify parameters that influence structural performance during earthquake fault rupture. In researching structures subject to surface rupture, both damaged and sound, guidelines and procedures to evaluate buildings in potential hazard areas are developed herein. Little to no guidance on how to design for surface fault offset exists in current codes and design guides. Thus it is important create tools for designers to appropriately analyze structures by developing guidance and requirements to aid designers in their strength assessment of a structure subject to this particular hazard. …

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

The Bridge Newsletter

-Creating bridge beams that will last 100 years
-Great school, great price
-Recruiting technical minds
-Combatting obesity, diabetes