Architecture Commons^™

Discrete Rigid Block Analysis To Assess Settlement Induced Damage In Unreinforced Masonry Façades, Ryan Ehresman, Nathan Taylor, Bora Pulatsu, Ece Erdogmus

Durham School of Architectural Engineering and Construction: Faculty Publications

In this study, a system of discontinuous rigid blocks is employed to simulate the possible damage mechanisms in unreinforced masonry (URM) façades and load-bearing frame systems subjected to settlement using the discrete element method (DEM). First, the employed modeling strategy is validated utilizing the available experimental results presented in the literature. Once there is a good agreement between the computational models and experimental findings, a sensitivity analysis is performed to quantify the influence of the input parameters defined in the DEM-based numerical model. Finally, the proposed modeling strategy is further utilized to assess the damage pattern that may develop in …

A Comparison Between Ultrasonic Guidedwave Leakage And Half-Cell Potential Methods In Detection Of Corrosion In Reinforced Concrete Decks, Ahmad Shoaib Amiri, Ece Erdogmus, Dana Richter-Egger

Durham School of Architectural Engineering and Construction: Faculty Publications

This article presents the advantages and limitations of a recently developed Ultrasonic Guided Wave Leakage (UGWL) method in comparison to the well-known Half-Cell Potential (HCP) method in their ability to detect corrosion in reinforced concrete (RC) bridge decks. This research also establishes a correlation between UGWL data and chloride content in concrete RC slabs. Concrete slabs submerged in a 10% NaCl solution were monitored using both methods over a period of six months. The chloride content from the three cores (0.84, 0.55, and 0.18%) extracted from the slab after the 6-month long process all exceeded the chloride threshold values suggested …

Facilitating The Industrial Sector's Adoption Of Collaborative Project Delivery Methods, Xavier Wood-Aliberch

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

In an effort to improve outcomes in the civil and healthcare sectors, clients have adopted collaborative project delivery methods for the delivery of their capital projects. The success stories in these sectors have gathered the attention of clients in the industrial sector, where cost and schedule overruns have become the norm. The central objective of this thesis is to help clients make the transition to this new type of project delivery.

This thesis was written in a three-paper format, where each paper addresses a challenge with the adoption of collaborative delivery methods. The first paper investigates what type of industrial …

Underground Construction And Space Utilization: A Bibliometric Analysis, Mugdha Praveen Kshirsagar Mrs, Sanjay Kantrao Kulkarni Dr, Nilesh Vedprakash Arora Mr, Devesh Dinesh Maheshwari Mr, Ankush Kumar Meena Mr

Library Philosophy and Practice (e-journal)

Land use optimization is a major concern as the world's population grows at an exponential rate. Surface land is already being depleted at an alarming pace. As a result, buildings can be constructed safely underground, allowing for more productive land use. The primary goal of this paper is to perform a bibliometric review of the literature related to Underground Construction in order to determine the growth of Underground Construction as a method of energy or land optimization in recent years. Between 1975 and 2020 is the time span considered for this survey. The results of the Scopus database are the …

Exploiting Pull-In/Pull-Out Hysteresis In Electrostatic Mems Sensor Networks To Realize A Novel Sensing Continuous-Time Recurrent Neural Network, Mohammad H. Hasan, Amin Abbasalipour, Hamed Nikfarjam, Siavash Pourkamali, Muhammad Emad-Un-Din, Roozbeh Jafari, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

The goal of this paper is to provide a novel computing approach that can be used to reduce the power consumption, size, and cost of wearable electronics. To achieve this goal, the use of microelectromechanical systems (MEMS) sensors for simultaneous sensing and computing is introduced. Specifically, by enabling sensing and computing locally at the MEMS sensor node and utilizing the usually unwanted pull in/out hysteresis, we may eliminate the need for cloud computing and reduce the use of analog-to-digital converters, sampling circuits, and digital processors. As a proof of concept, we show that a simulation model of a network of …

Quasi-Static Nonlinear Seismic Assessment Of A Fourth Century A.D. Roman Aqueduct In Istanbul, Turkey, Semih Gonen, Ece Erdogmus, Engin Karaesmen, Erhan Karaesmen

Durham School of Architectural Engineering and Construction: Faculty Publications

The majority of architectural heritage consists of load-bearing masonry components made up of stone units and relatively weak mortar joints, yielding potential weak planes for masonry structures where tension and shear failures are expected to occur. Advanced nonlinear analyses are required to simulate these phenomena and predict the corresponding nonlinear structural behavior of historic masonry constructions. In this context, this paper presents a model of a stone masonry Roman aqueduct (the Valens Aqueduct), constructed in the fourth century A.D. in Istanbul, Turkey, to explore the seismic capacity and behavior using the discrete element method (DEM). The employed modeling approach comprises …

Feasibility Of Lora For Smart Home Indoor Localization, Kyungki Kim, Sining Li, Milad Heydariaan, Nour Smaoui, Omprakash Gnawali, Wonho Suh, Min Jae Suh, Jung In Kim

Durham School of Architectural Engineering and Construction: Faculty Publications

With the advancement of low-power and low-cost wireless technologies in the past few years, the Internet of Things (IoT) has been growing rapidly in numerous areas of Industry 4.0 and smart homes. With the development of many applications for the IoT, indoor localization, i.e., the capability to determine the physical location of people or devices, has become an important component of smart homes. Various wireless technologies have been used for indoor localization includingWiFi, ultra-wideband (UWB), Bluetooth low energy (BLE), radio-frequency identification (RFID), and LoRa. The ability of low-cost long range (LoRa) radios for low-power and long-range communication has made this …

Enhancing Bim Implementation In The Ethiopian Public Construction Sector: An Empirical Study, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei3

Durham School of Architectural Engineering and Construction: Faculty Publications

Recently, the popularity of BIM has grown rapidly in the public construction sector. However, only a few studies so far have been seeking to address the BIM adoption benefits and barriers in developmental public projects across the low-income countries. Thus, the study aims to investigate the benefits and barriers of BIM adoption in the context of the Ethiopian infrastructure market. To achieve the objectives, a comprehensive systematic literature review was conducted to identify BIM adoption benefits and barriers in developing countries. Then, a structured questionnaire survey was conducted to collect data from various professionals working in organizations including client, consultant, …

Condition Rating Prediction Using An Interactive Deterioration Model Development Package, Minwoo Chang, Mitchell S. Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents an advanced method to determine explanatory variables required for developing deterioration models without the interference of human bias. Although a stationary set of explanatory variables is ideal for long-term monitoring and asset management, the penalty regression results vary annually due to the innate bias in the inspection data. In this study, weighting factors were introduced to consider the inspection data collected for several years, and the most stationary set was identified. To manage the substantial amount of inspection data effectively, we proposed a software package referred to as the Deterioration Model Development Package (DMDP). The objective of …

Framework For Extracting And Characterizing Load Profile Variability Based On A Comparative Study Of Different Wavelet Functions, Andrew Parker, Kevin James, Dongming Peng, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

The penetration of distributed energy resources (DERs) on the electric power system is changing traditional power flow and analysis studies. DERs may cause the systems' protection and control equipment to operate outside their intended parameters, due to DERs' variability and dispatchability. As this penetration grows, hosting capacity studies as well as protection and control impact mitigation become critical components to advance this penetration. In order to conduct such studies accurately, the electric power system's distribution components should be modeled correctly, and will require realistic time series loads at varying temporal and spatial conditions. The load component consists of the built …

An Iot Framework For Modeling And Controlling Thermal Comfort In Buildings, Fadi Alsaleem, Mehari K. Tesfay, Mostafa Rafaie, Kevin Sinkar, Dhaman Besarla, Parthiban Arunasalam

Durham School of Architectural Engineering and Construction: Faculty Publications

Humans spend more than 90% of their day in buildings, where their health and productivity are demonstrably linked to thermal comfort. Building thermal comfort systems account for the largest share of U.S energy consumption. Despite this high-energy cost, due to building design complexity and the variety of building occupant needs, addressing thermal comfort in buildings remains a difficult problem. To overcome this challenge, this paper presents an Internet of Things (IoT) approach to efficiently model and control comfort in buildings. In the model phase, a method to access and exploit wearable device data to build a personal thermal comfort model …

An Experiential Online Training Approach For Underrepresented Engineering And Technology Students, Arefeh Mohammadi, Kevin Grosskopf, John Killingsworth

Durham School of Architectural Engineering and Construction: Faculty Publications

Workforce pipelines are essential to sustain a productive workforce in an increasingly competitive, high-tech environment. Advanced automation, sensors, materials and data analytics will increase the need for highly skilled workers in the manufacturing (and manufactured construction) sector. Attracting and developing the next-generation workforce is not without its challenges; however, students are often deficient in technical skills and generally have negative perceptions about manufacturing and construction. As a result, new education and training models have been developed to provide instruction at all levels of the educational system, with a focus on both traditional students and non-traditional students, including ethnic minorities, women, …

Investigating Multidimensional Characteristics Of Noise Signals With Tones From Building Mechanical Systems And Their Effects On Annoyance, Joonhee Lee, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper investigates multidimensional characteristics of tonal noise from heating, ventilation, and air-conditioning systems, besides loudness and tonality, to improve prediction of annoyance. Two studies were conducted: multidimensional scaling (MDS) analysis to determine what other perceptual signal characteristics are important and perceptual weight analysis (PWA) to understand the impact of multiple tones in a signal. In the MDS study, paired comparison tasks were conducted to gather similarity and annoyance data. Results show that the latent perceptual dimensions are related to the signal’s tonality, loudness, sharpness, and roughness. Including metrics for these perceptions, except roughness, improves the performance of earlier annoyance …

A Novel Structural Health Monitoring Method For Reinforced Concrete Bridge Decks Using Ultrasonic Guided Waves, Ece Erdogmus, Eric Garcia, Ahmad Shoaib Amiri, Michael Schuller

Durham School of Architectural Engineering and Construction: Faculty Publications

This article presents the latest improvements in a recently developed nondestructive testing (NDT) approach for early detection of various flaws (corrosion, delamination, and concrete cracking) in reinforced concrete (RC) bridge decks. The proposed method involves the use of internal steel reinforcement as a wave guide for transmitting ultrasonic waves through the system and the measurement of leaked energy from the surface of the concrete. This paper builds upon the progress made in the previously published phases of the project and aims to further explore the capabilities and practicality of the proposed NDT method. Specifically, the limits of propagation distance, effect …

Mechanical Connection For Concrete Structures, George Morcous, Raed Tawadrous

Durham School of Architectural Engineering and Construction: Faculty Publications

A system and method for connecting precast concrete structures includes anchoring a sleeve within a pocket formed in one of the concrete structures , and placing the concrete structures in contact with one another such that the pocket is diposed around a protruding end of a shear connector embedded in the other concrete structure . A bridge is inserted around the protruding end of the shear connector and a fastener is installed onto the protruding end of the shear connector to engage the bridge and urge the bridge in abutting relation with a lip of the sleeve . The pocket …

Workforce Development Through Online Experiential Learning For Stem Education, Arefeh Mohammadi, Kevin Grosskopf, John Killingsworth

Durham School of Architectural Engineering and Construction: Faculty Publications

The U.S. workforce is increasingly comprised of older adults, women, and minorities who lack basic skills and are unable to acquire these skills through traditional educational and training programs. New approaches are needed to provide effective training to the adult learner and flexible support for nontraditional students who must balance work-life demands with limited educational opportunities. Contextualized teaching and learning (CTL) is a form of experiential learning that blends both basic skills and occupational training together in environments that allow students to relate subject matter to real-world situations. Virtual CTL environments can be created to better engage students, provide immediate …

Automated Generation Of Daily Evacuation Paths In 4d Bim, Kyungki Kim, Yong-Cheol Lee

Durham School of Architectural Engineering and Construction: Faculty Publications

Spatial movements of workers and equipment should be carefully planned according to project plans. In particular, it is crucial for workers’ safety to prepare emergency evacuation paths according to changing construction site configurations and construction progress. However, creating evacuation paths for all crews for each day can be an extremely labor-intensive task if it is done manually. Consequently, in most construction projects, evacuation plans are not provided to managers and crews throughout the entire construction. Even state-of-the-art technologies do not suggest ways to generate evacuation paths according to changing progresses presented in 4-Dimensional Building Information Model (4D BIM). This research …

Efficient Excitation Of Micro/Nano Resonators And Their Higher Order Modes, N. Jaber, M. A. A. Hafiz, S. N. R. Kazmi, M. H. Hasan, F. Alsaleem, S. Ilyas, M. I. Younis

Durham School of Architectural Engineering and Construction: Faculty Publications

We demonstrate a simple and flexible technique to efficiently activate micro/nano-electromechanical systems (MEMS/NEMS) resonators at their fundamental and higher order vibration modes. The method is based on the utilization of the amplified voltage across an inductor, L, of an LC tank resonant circuit to actuate the MEMS/NEMS resonator. By matching the electrical and mechanical resonances, significant amplitude amplification is reported across the resonators terminals. We show experimentally amplitude amplification up to twelve times, which is demonstrated to efficiently excite several vibration modes of a microplate MEMS resonator and the fundamental mode of a NEMS resonator.

Voltage And Deflection Amplification Via Double Resonance Excitation In A Cantilever Microstructure, Mohammad H. Hasan, Fadi Alsaleem, Abdallah Ramini

Durham School of Architectural Engineering and Construction: Faculty Publications

Cantilever electrostatically-actuated resonators show great promise in sensing and actuating applications. However, the electrostatic actuation suffers from high-voltage actuation requirements and high noise low-amplitude signal-outputs which limit its applications. Here, we introduce a mixed-frequency signal for a cantilever-based resonator that triggers its mechanical and electrical resonances simultaneously, to overcome these limitations. A single linear RLC circuit cannot completely capture the response of the resonator under double resonance excitation. Therefore, we develop a coupled mechanical and electrical mathematical linearized model at different operation frequencies and validate this model experimentally. The double-resonance excitation results in a 21 times amplification of the voltage …

Experiencing Extreme Height For The First Time: The Influence Of Height, Self-Judgment Of Fear And A Moving Structural Beam On The Heart Rate And Postural Sway During The Quiet Stance, Mahmoud Habibnezhad, Jay Puckett, M. S. Fardhosseini, Houtan Jebelli, Terry Stentz, L. A. Pratama

Durham School of Architectural Engineering and Construction: Faculty Publications

Falling from elevated surfaces is the main cause of death and injury at construction sites. Based on the Bureau of Labor Statistics (BLS) reports, an average of nearly three workers per day suffer fatal injuries from falling. Studies show that postural instability is the foremost cause of this disproportional falling rate. To study what affects the postural stability of construction workers, we conducted a series of experiments in the virtual reality (VR). Twelve healthy adults—all students at the University of Nebraska-Lincoln—were recruited for this study. During each trial, participants’ heart rates and postural sways were measured as the dependent factors. …

Skip This Chore: Cleaning Your Air Conditioner Condenser Probably Won't Make It Work Better, David Yuill

Durham School of Architectural Engineering and Construction: Faculty Publications

I asked my neighbor who hoses off his air conditioner condenser every spring why he does it. “Because my dad always told me I had to,” he said.

Conventional wisdom like what my neighbor’s dad imparted may always seem right. But through my HVAC scholarship – the study of heating, ventilation and air-conditioning systems – I’ve learned that this particular presumption is probably wrong.

Prediction Of Stress Increase At Ultimate In Unbonded Tendons Using Sparse Principal Component Analysis, Eric Mckinney, Minwoo Chang, Marc Maguire, Yan Sun

Durham School of Architectural Engineering and Construction: Faculty Publications

While internal and external unbonded tendons are widely utilized in concrete structures, an analytical solution for the increase in unbonded tendon stress at ultimate strength, ∆f_ps, is challenging due to the lack of bond between strand and concrete. Moreover, most analysis methods do not provide high correlation due to the limited available test data. The aim of this paper is to use advanced statistical techniques to develop a solution to the unbonded strand stress increase problem, which phenomenological models by themselves have done poorly. In this paper, Principal Component Analysis (PCA), and Sparse Principal Component Analysis (SPCA) …

Need For Aeromedical Evacuation High-Level Containment Transport Guidelines, Shawn G. Gibbs, Jocelyn J. Herstein, Aurora B. Le, Elizabeth L. Beam, Theodore J. Cieslak, James V. Lawler, Joshua L. Santarpia, Terry L. Stentz, Kelli R. Kopocis-Herstein, Chandran Achutan, Gary W. Carter, John J. Lowe

Durham School of Architectural Engineering and Construction: Faculty Publications

Circumstances exist that call for the aeromedical evacuation high-level containment transport (AE-HLCT) of patients with highly hazardous communicable diseases. A small number of organizations maintain AE-HLCT capabilities, and little is publicly available regarding the practices. The time is ripe for the development of standards and consensus guidelines involving AE-HLCT.

A Practitioner’S Guide To Small Unmanned Aerial Systems For Bridge Inspection, Sattar Dorafshan, Robert J. Thomas, Calvin Coopmans, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Small unmanned aerial system(s) (sUAS) are rapidly emerging as a practical means of performing bridge inspections. Under the right condition, sUAS assisted inspections can be safer, faster, and less costly than manned inspections. Many Departments of Transportation in the United States are in the early stages of adopting this emerging technology. However, definitive guidelines for the selection of equipment for various types of bridge inspections or for the possible challenges during sUAS assisted inspections are absent. Given the large investments of time and capital associated with deploying a sUAS assisted bridge inspection program, a synthesis of authors experiences will be …

Benchmarking Image Processing Algorithms For Unmanned Aerial System-Assisted Crack Detection In Concrete Structures, Sattar Dorafshan, Robert J. Thomas, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper summarizes the results of traditional image processing algorithms for detection of defects in concrete using images taken by Unmanned Aerial Systems (UASs). Such algorithms are useful for improving the accuracy of crack detection during autonomous inspection of bridges and other structures, and they have yet to be compared and evaluated on a dataset of concrete images taken by UAS. The authors created a generic image processing algorithm for crack detection, which included the major steps of filter design, edge detection, image enhancement, and segmentation, designed to uniformly compare dierent edge detectors. Edge detection was carried out by six …

Remotely Testing Whether A Climate Control System Controller Is Correctly Installed, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Disclosed are exemplary embodiments of apparatus and methods for remote testing of controllers such as thermostats, to detect incorrect climate control system configuration parameters . In an exemplary embodiment, a computer wirelessly connects with a remote thermostat and sends signal (s) to the thermostat instructing the thermostat to perform climate control function (s) in predefined sequence (s). The computer receives signal (s) from the thermostat indicating whether the thermostat is performing the climate control function (s) in accordance with the sent signal (s). Based on the signal (s) received from the thermostat, the computer determines whether the thermostat is configured …

Method Of Monitoring Charge Condition Of Heat Pump System, Fadi M. Alsaleem, Gregg M. Hemmelgarn

Durham School of Architectural Engineering and Construction: Faculty Publications

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air down stream of the indoor …

Hvac System Remote Monitoring And Diagnosis, Jeffrey N. Arensmeier, Gregg M. Hemmelgarn, Fadi M. Alsaleem, Priotomo Abiprojo

Durham School of Architectural Engineering and Construction: Faculty Publications

A monitoring system for an HVAC system of a building includes a monitoring server located remotely from the building. The monitoring server receives, from a device installed at the building, (i) time-domain current data based on a measured aggregate current supplied to a plurality of components of the HVAC system, and (ii) data based on frequency-domain current data of the measured aggregate current. Based on the received data, the monitoring server accesses (i) whether a failure has occurred in a first com ponent of the plurality of components and (ii) generates a preliminary advisory in response to determining that the …

Building Envelope And Interior Grading Systems And Methods, Fadi Mohammad Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A difference module determines differences between an outdoor ambient temperature and an indoor temperature, determines a first average of the differences , and determines a second average of the differences. A storing module stores a first data point, the first data point including the first average and a first total run time of a heating, ventilation, and/or air conditioning (HVAC) system, and stores a second data point, the second data point including the second average and a second total run time of the HVAC system. A fitting module fits a line to the first and second data points. An envelope …

Heat Pump And Air Conditioning Grading Systems And Methods, Fadi Mohammad Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

An expectation module determines an expected average power consumption of a heat pump for a predetermined period as a function of indoor and outdoor temperatures of the building during the predetermined period. A difference module determines a power difference between an average power consumption of the heat pump during the predeter mined period and the expected average power consumption of the heat pump for the predetermined period. A grade determination module determines a grade of the heat pump for the predetermined period based on the power difference of the predetermined period. A reporting module generates a displayable report including the …