Architecture Commons^™

Structural Damage Detection Utilizing Experimental Mode Shapes, Evan Jamison Gerbo

Master's Theses

A method of locating structural damage is developed and tested to aid in the evaluation of structural health. This method will help minimize the cost of structural inspection and repair by informing engineers of where damage, due a seismic event, has occurred before the removal of finishes for visual inspection. This thesis begins to answer the question “can structural damage be detected solely through analysis of experimentally measured mode shapes?”

The work encompasses construction of a test structure, with three braces that can be repeatedly engaged or dis-engaged, thus allowing for testing of a variety of braced configurations. For this …

Water Recycling In Green Buildings: Grey Water Treatment And Reuse Benefits In Al-Wagan Residential Neighborhood In Al-Ain City, Al Dehaim Nassib Suhail Yatba Al Ameri

Theses

Water scarcity is a worldwide problem that called for a wiser and more sustainable resources' management. Grey waste water treatment is considered a widely spread technology that dominates water management in order to substitute the potential deficiencies.

Water use in the last three decades in the UAE has witnessed both a great increase and pressure on groundwater and desalinated water. This consequently has called for continuous, serious and diversified efforts to simultaneously improve the supply and sustain the water use by treatment and recycling. Besides UAE's natural population growth, the demand for water is also expected to increase significantly in …

Effects Of Polyethylene Terephthalate Fibers In The Water Resistance Of Compressed Stabilized Earth Blocks., Ebrima Colley

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

This research project focuses on investigating the effects of synthetic fibers (PET) and amount of cement stabilization on the water absorption, water surface erosion, and wet compressive strength of the compressed stabilized earth blocks (CSEB). The use of locally available soils blended with fibers and cement was investigated to obtain a design mix for compressed stabilized earth blocks capable of staying intact in wet and humid regions in the world (i.e. regions with annual rainfall of over 50 in). Blocks with varying cement percentages of 5, 8, 10, and 15% by weight were produced with 3 specimens each, with and …

Energy Benefits Of Different Dedicated Outdoor Air Systems Configurations In Various Climates, Shihan Deng

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

Dedicated Outdoor Air Systems (DOAS) are proven to be beneficial in many practices. However, not all DOAS configurations under different climates provide the same benefits. This study presents a simulation on evaluating various energy saving benefits of different DOAS configurations among diverse climate zones of commercial buildings in the United States.

Three DOAS configurations in a medium office building are simulated in this study: (1) fan-coil units (FCUs) as terminal units with a DOAS unit supplying conditioned outdoor air (OA) to each FCU intake; (2) FCUs with a DOAS unit supplying conditioned OA directly to each occupied space; and (3) …

On A Combined Adaptive Tetrahedral Tracing And Edge Diffraction Model, Carl R. Hart

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

A major challenge in architectural acoustics is the unification of diffraction models and geometric acoustics. For example, geometric acoustics is insufficient to quantify the scattering characteristics of acoustic diffusors. One method of quantifying the scattering characteristics of acoustic diffusers is through computational prediction, typically via the time-independent boundary element method (BEM). In contrast, time-domain computations are of interest for characterizing both the spatial and temporal scattering characteristics of acoustic diffusors. Hence, a method is sought that predicts acoustic scattering in the time-domain. A prediction method, which combines an advanced image source method and an edge diffraction model, is investigated for …

Effects Of Tendon Spacing On In-Plane Behavior Of Posttensioned Masonry Walls, Dongun Ryu, Anil C. Wijeyewickrema, Mohamed A. Elgawady, M. A.K.M. Madurapperuma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In-plane behavior of unbonded posttensioned clay brick masonry walls are investigated using detailed finite-element (FE) models. FE models of three walls having different aspect ratios of 1.50, 1.00, and 0.67 are developed. Effects of tendon spacing on in-plane behavior of these walls are investigated using different tendon spacings ranging from 0.61 m (2 ft) to 3.81 m (12.5 ft). In addition, the effects of having different horizontal reinforcement ratios of 0%, 0.1%, and 0.5% on the in-plane behavior of the walls were investigated. The stresses in the tendons are calculated using different approaches, and then the flexural strength of each …

A Unifying Framework For Parameterizing Stably Stratified Shear-Flow Turbulence, Benjamin D. Mater, Subhas Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

An alternative framework for parameterizing stably stratified shear-flow turbulence is presented. Using dimensional analysis, four non-dimensional parameters of interest are identified that consider the independent effects of stratification, shear, viscosity, and scalar diffusivity. In the interest of geophysical applications, the problem is further simplified by considering only high Reynolds number flow. This leads to a two-dimensional parameter space based on a buoyancy strength parameter (i.e., an inverse Froude number) and a shear strength parameter. Consideration for the gradient Richardson number allows the space to be divided into an unforced regime, a shear dominated regime, and a buoyancy-dominated regime. On this …

Building And Maintaining Plankhouses At Two Villages On The Southern Northwest Coast Of North America, Emily Evelyn Shepard

Dissertations and Theses

Plankhouses were functionally and symbolically integral to Northwest Coast societies, as much of economic and social life was predicated on these dwellings. This thesis investigates both plankhouse architecture and the production of these dwellings. Studying plankhouse construction and maintenance provides information regarding everyday labor, landscape use outside of villages, organization of complex tasks, and resource management.

This thesis investigates three plankhouse structures at two sites, Meier and Cathlapotle, in the Lower Columbia River Region of the southern Northwest Coast of North America. Methods consisted of digitizing over 1,100 architectural features, creating detailed maps of architectural features, and conducting statistical and …

A Comparative Study Of The Mechanical Properties, Fracture Behavior, Creep, And Shrinkage Of Chemically Based Self-Consolidating Concrete, Mahdi Arezoumandi, Mark Ezzell, Jeffery S. Volz

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study presents the results of an experimental investigation that compares the mechanical properties, fracture behavior, creep, and shrinkage of a chemically based self-consolidating concrete (SCC) mix with that of a corresponding conventional concrete (CC) mix. The CC and SCC mix designs followed conventional proportioning in terms of aggregate type and content, cement content, air content, water-cementitious materials (w/cm) ratio, and workability. Then, using only chemical admixtures, the authors converted the CC mix to an SCC mix with all of the necessary passing, filling, flowability, and stability requirements typically found in SCC. The high fluidity was achieved with a polycarboxylate-based …

An Experimental Investigation Of Crumb Rubber Concrete Confined By Fibre Reinforced Polymer Tubes, Osama Youssf, Mohamed Elgawady, Julie E. Mills, Xing Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Due to the known loss of compressive strength experienced by crumb rubber concrete (CRC) compared with conventional concrete, there have been few applications explored to date for the structural use of these materials. This paper describes experimental work conducted to explore the possible future use of CRC for structural columns by evaluating the use of fiber reinforced polymer (FRP) confinement as a means of overcoming the material deficiencies (decreased compressive strength). The results indicated that the use of FRP to confine rubberized concrete effectively negates the decrease in strength and retains the advantages of increased ductility that arise from rubberized …

Plant Translocation Of Organic Compounds: Molecular And Physicochemical Predictors, Matt A. Limmer, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Root-Soil Boundary Represents One of the Largest Global Biotic-Abiotic Mass-Transfer Interfaces and is a Primary Pollutant Entry Point to the Food Chain. This Interface is Also Critically Important in Phytoremediation Efforts and Herbicide Design. Experimental Data and Single-Parameter Models Have Resulted in the Current Understanding that Moderately Hydrophobic Organic Compounds Are Most Likely to Be Translocated by Plants, Although Recent Evidence Indicates Plants Can Also Translocate Some Hydrophilic Compounds. Molecular Descriptors Initially Applied for Drug Discovery and for Transmembrane Migration in Mammalian Systems Were Applied Here to Determine the Physicochemical Domains and Weighted Desirability Functions to Identify Compounds Amenable …

Performance Of No Vibration/No Admixture Masonry Grout Containing High Replacement Of Portland Cement With Fly Ash And Ground Granulated Blast Furnace Slag, Eric Bateman

Master's Theses

When hollow concrete masonry is used for construction in high seismic regions, structural designs typically require fully grouted walls. The grouting process is labor-intensive, time-consuming and has a high energy demand due to requirements of consolidation in each and subsequent grout lifts. Self-consolidating grout with admixtures has been successfully used without segregation in walls of up to 12.67 ft. in height. Investigation of self-consolidating grout mixes without admixtures has potential for sustainability improvement.

This thesis reports on the compression strength and consolidation observations of self-consolidating characteristics of no vibration/no admixture grout made by substituting various proportions of Portland cement with …

The Bridge Newsletter Spring 2014, Missouri University Of Science And Technology

The Bridge Newsletter

-Reusing scrap tires
-Renaissance man
-Energy research published
-Follow your passion

Improving The Hydraulics Of Drinking Water Contact Tanks Using Random Packing Material, Taylor C. Barnett, Justin J. Kattnig, Subhas K. Venayagamoorthy, Gordon Whittaker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the use of industrial packing material for increasing the hydraulic efficiency of small-scale, chlorine contact tanks used in drinking water treatment. The packing material used in the study was spherical, with porosities between 0.9 and 0.95 and a density less than that of water. A total of 67 tracer studies, conducted on laboratory-scale chlorine contact tank systems, investigated three sizes of packing material, two tank sizes, and two flow rates. Sodium chloride solution was injected as a continuous tracer and was monitored in the tank outflow through electrical conductivity. Several studies were validated with the use and …

Method And System For Optimal Coordination Control And Soft Repair Of Multiple Rooftop Heating And Cooling Units, Haorong Li

Durham School of Architectural Engineering and Construction: Faculty Publications

Techniques are described that may be implemented in an adaptive control device to regulate multiple zone environmental units based upon multiple temperature values and multiple airflow values, where each temperature value and each airflow value is related to the temperature and the airflow in a specific zone. In an implementation, the input interface of the adaptive control device is configured to receive multiple temperature values and multiple air flow values from multiple zone sensors. The adaptive control device may calculate multiple operational values based on the multiple temperature values and the multiple air flow values. An operational value indicates a …

2014 Scholarly Productivity Report, Missouri University Of Science And Technology

Civil, Architectural and Environmental Engineering Scholarly Productivity Reports

No abstract provided.

The Steel Yard, Architecture Department, Sculpture Department, Bruner Foundation

Rudy Bruner Award | 30 Years of Urban Excellence

The Steel Yard redeveloped a historic steel fabrication facility into a campus for arts education, job training, and small-scale manufacturing in Providence, Rhode Island. The 3.5-acre property in the city’s Industrial Valley required extensive environmental remediation to meet regulatory requirements while retaining the industrial urban character of the site. The Steel Yard offers classes, workforce training, and fabrication space for local artists, creating an industrial arts incubator where they can share ideas, materials, and space. It has become a center for creative activity, bridging the gap between the traditional arts community on the affluent east side of Providence with manufacturing …

Stock Aggregation Model And Virtual Archetype For Large Scale Retrofit Modelling Of Local Authority Housing In Ireland, James Pittam, Paul D. O’Sullivan, Garrett O’Sullivan

Conference Papers

Developing representative archetypes using a bottom up approach for stock modelling is an excellent tool for evaluating the overall performance of the building stock; however it requires detailed analysis of the various building types. Currently there is no detailed housing data base for Local Authority housing in Cork City, Ireland that catalogues the housing stocks geometric properties and thermal characteristics for each typology. This study details a methodology to catalogue the LAH stock and build a detailed housing data base. The GIS web based mapping application Google Street View is used to identify 20 house typologies across 36 LAH developments; …

The Influence Of National Culture On Effectiveness Of Safety Trainings During Postdisaster Reconstruction, Behzad Esmaeili, Kevin Grosskopf, Amy Javernick-Will

Durham School of Architectural Engineering and Construction: Faculty Publications

Non-English speaking workers constitute a disproportionately high number of workers involved in postdisaster reconstruction. Additionally, the rate of fatality among these workers is higher than the industry average. Research shows this population is more prone to unsafe behaviors in the working environment, conceivably because many of these workers are sent into the field prior to any formalized training. Recent studies show that the native culture of construction workers can impact risk-taking behavior. While numerous researchers have attempted to develop training materials for Hispanic workers, the number of studies that consider the impact of native culture on safety behavior is minimal. …

A Transient Community For A Transient Lifestyle, Sameh Mohamed Ibrahim

Theses and Dissertations

The project suggests an alternative means for living in Qatar. It proposes the development of a transient, floating community a man-made, transitory archipelago of floating housing units located at the ‘soon to be abandoned’ docks a short distance from the Museum of Islamic Art and the Doha Corniche. The design, through a variety of bespoke dwelling options, can provide both more and less nomadic housing to accommodate a variety of dif- ferent lifestyles and social units. Clustered around three permanent islands (containing a cultural/activity center, three adaptable ‘work-unit’ towers, and a park/commercial area), the design provides a wide set of …

Hybrid Of Natural Element Method (Nem) With Genetic Algorithm (Ga) To Find Critical Slip Surface, Shahriar Shahrokhabadi, Vahid Khoshfahm, Hamed Nabizadeh Rafsanjani

Durham School of Architectural Engineering and Construction: Faculty Publications

One of the most important issues in geotechnical engineering is the slope stability analysis for determination of the factor of safety and the probable slip surface. Finite Element Method (FEM) is well suited for numerical study of advanced geotechnical problems. However, mesh requirements of FEM creates some difficulties for solution processing in certain problems. Recently, motivated by these limitations, several new Meshfree methods such as Natural Element Method (NEM) have been used to analyze engineering problems. This paper presents advantages of using NEM in 2D slope stability analysis and Genetic Algorithm (GA) optimization to determine the probable slip surface and …

Development Of A Tribometer To Characterize Lubrication Layer Properties Of Self-Consolidating Concrete, Dimitri Feys, Kamal Khayat, Aurelien Perez-Schell, Rami Khatib

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Last Decade, Significant Advances Have Been Made in Investigating, Understanding and Predicting the Flow Characteristics during Pumping of Concrete. Kaplan Developed Theoretical Equations based on the Rheological and Tribological Properties of Concrete to Predict Pumping Pressures. Several Tribometers Were Developed to Characterize the Flow Properties of Concrete Along a Smooth Wall, But None of Them Allows the Use of Highly Workable Concretes. the Main Reason is that for the Calculation of the Yield Stress and Viscous Constant of the Lubrication Layer, the Concrete is Not Allowed to Be Sheared. in This Paper, a New Design for the Concrete Tribometer …

Shear Strength Of Chemically Based Self-Consolidating Concrete Beams: Fracture Mechanics Approach Versus Modified Compression Field Theory, Mahdi Arezoumandi, Jeffery S. Volz

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

An experimental investigation was conducted to study the shear strength of full-scale beams constructed with both chemically based self-consolidating concrete (SCC) and conventional concrete (CC). This experimental program consisted of 12 beams without stirrups with three different longitudinal reinforcement ratios. The beams were tested under a simply supported four-point loading condition. The experimental shear strengths of the beams were compared with the shear provisions of both U.S. and international design codes. Furthermore, the shear strengths of the beams were evaluated based on fracture mechanics approaches, modified compression field theory (MCFT), and a shear database of CC specimens. Results of this …

Role Of Solids Retention Time On Complete Nitrification: Mechanistic Understanding And Modeling, Guoqiang Liu, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Effects of solids retention time (SRT) on both steps of the nitrification process (e.g., ammonia oxidation and nitrite oxidation) and the nitrifier community in a complete-mix activated sludge process were studied. At a SRT less than or equal to 20 days, the effluent ammonia concentration was lower than the effluent nitrite concentration. At the 40-day SRT, however, the effluent nitrite concentration became equal to or less than the effluent ammonia concentration. Quantitative Polymerase Chain Reaction (QPCR) assays indicated that increasing SRT significantly increased nitrite-oxidizing bacteria/ammonia-oxidizing bacteria (NOB/AOB) ratio. Further investigation indicated that Nitrosomonas europaea/eutropha were the dominant AOB for ammonia …

Full-Scale Field Testing Of Micropiles In Stiff Clay Subjected To Combined Axial And Lateral Loads, Kyle A. Kershaw, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A series of full-scale micro piles was installed at a site in mid-Missouri for a load-test program to study the effect of combined loading. The micro piles were installed with a 178-mm (7-in.) outer diameter steel casing to a depth of 4.6 m (15 ft) and a bond zone length of 3.0 m (10 ft). The surficial soils at the site consisted of stiff-to-hard clay underlain by weathered silty/sandy shale where the bond zone of the micro piles was located. The load-test program included axial, lateral, and combined-load tests. The ultimate axial and lateral capacity of the piles was initially …

Effects Of Mix Design Parameters And Rheological Properties On Dynamic Stability Of Self-Consolidating Concrete, B. Esmaeilkhanian, Kamal Khayat, A. Yahia, D. Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Stability is a crucial property for successful placement and performance of self-consolidating concrete (SCC). Dynamic stability refers to the segregation resistance of concrete during flow and is not thoroughly described in literature to date. In this research, a newly developed dynamic stability test, the Tilting-box test, was employed to evaluate the effect of different mix design parameters on the dynamic segregation of SCC. Paste volume, water-to-binder ratio (w/b), maximum size of aggregate (MSA), aggregate density, and aggregate grain-size distribution were shown to affect the dynamic stability of SCC, while the coarse aggregate shape did not have a significant influence. The …

Virtual Surface Temperature Sensor For Multi-Zone Commercial Buildings, Yuebin Yu, Denchai Woradechjumroen, Daihong Yu

Durham School of Architectural Engineering and Construction: Faculty Publications

Multi-zone structure is commonly used in small commercial office buildings, retail stores and supermarket. While there is no adjacent wall between the zones, the impact of a neighbor zone on the current zone can be approximated and analyzed through the application of virtual walls. It is critical to accurately estimate the virtual wall surface temperature in order to evaluate the model uncertainty and apply improved supervisory control on multiple rooftop air-conditioning units (RTUs). We propose an innovative virtual surface temperature sensor based on system-identification to solve this challenge. The validation of the virtual temperature model is processed by the three …

Shallow Flat Soffit Precast Concrete Floor System, George Morcous, Maher Tadros

Durham School of Architectural Engineering and Construction: Faculty Publications

A precast concrete floor system that eliminates the need for column corbels and beam ledges while being very shallow. The main advantages of the present system include a span to-depth ratio of 30, a flat soffit, economy, consistency with prevailing erection techniques, and fire and corrosion protection. The present system consists of continuous precast columns, prestressed rectangular beams, hollow-core planks, and cast-in-place composite topping. Testing results have indicated that a 12 inch deep flat soffit precast floor system has adequate capacity to carry gravity loads (including 100 psf live load) in a 30 ft x 30 ft bay size. Testing …

Summary Of Large-Scale Nonplanar Reinforced Concrete Wall Tests, Anahid A. Behrouzi, Andrew Mock, Laura Lowes, Dawn Lehman, Daniel Kuchma

Architectural Engineering

Nonplanar wall configurations are prevalent in engineering practice, yet relatively little research has addressed nonplanar walls and the earthquake response of these components remains poorly understood. A recent experimental test program conducted by the authors investigated the earthquake response of modern, ACI Code compliant C‐shaped walls subjected to unidirectional and bidirectional lateral loading. To compare the results of this study with previous experimental investigations conducted by others, this document examines laboratory tests of slender nonplanar walls available in the literature. Response histories, damage patterns, drift capacity and failure mechanisms are used to characterize the behavior of each nonplanar wall test …

Use Of Innovative Techniques To Enhance The Hydraulic Disinfection Efficiency Of Drinking Water Contact Tanks, J. J. Kattnig, S. K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The focus of this study was to understand the complex nature of flow dynamics within water disinfection contact tanks and to use this understanding in the development of beneficial tank modifications. Methods involved in this process included the use of computational fluid dynamics (CFD) and physical conservative tracer studies. Attempted tank alterations included the installation of baffles, inlet modification, and the use of industrial packing material. Tested modifications aimed at altering existing velocity fields to increase the hydraulic disinfection efficiency of a given system. Hydraulic efficiency was measured through the use of residence time distribution (RTD) curves and the well-known …