Construction Engineering Commons^™

Foreign Object Debris Detection For Airport Pavement Images Based On Self-Supervised Localization And Vision Transformer, Travis Munyer, Daniel Brinkman, Xin Zhong, Chenyu Huang, Iason Konstantzos

Durham School of Architectural Engineering and Construction: Faculty Publications

Supervised object detection methods provide subpar performance when applied to Foreign Object Debris (FOD) detection because FOD could be arbitrary objects according to the Federal Aviation Administration (FAA) specification. Current supervised object detection algorithms require datasets that contain annotated examples of every to-be-detected object. While a large and expensive dataset could be developed to include common FOD examples, it is infeasible to collect all possible FOD examples in the dataset representation because of the openended nature of FOD. Limitations of the dataset could cause FOD detection systems driven by those supervised algorithms to miss certain FOD, which can become dangerous …

Zero Net Energy Test House, Timothy Hemsath, James D. Goedert, Avery Don Schwer, Yong Cho

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper describes the first phase of a residential research program to reduce the impact of new construction on the environment through research and education using a Zero Net Energy Test House as a framework. Containing four bedrooms, three and a half baths, the 1,800 square foot house, 1,000 square foot basement, is located in Omaha, Nebraska. It is being used to validate several research projects and provides a platform for applications research of a number of technological advances. Laminated photovoltaic solar panels, a wind turbine, and an occupant monitoring energy control system are some of the sustainable design innovations …

Intelligibility Of Medically Related Sentences In Quiet, Speech-Shaped Noise, And Hospital Noise, Tessa Bent, Melissa Baese-Berk, Erica E. Ryherd, Sidney Perry

Durham School of Architectural Engineering and Construction: Faculty Publications

Noise in healthcare settings, such as hospitals, often exceeds levels recommended by health organizations. Although researchers and medical professionals have raised concerns about the effect of these noise levels on spoken communication, objective measures of behavioral intelligibility in hospital noise are lacking. Further, no studies of intelligibility in hospital noise used medically relevant terminology, which may differentially impact intelligibility compared to standard terminology in speech perception research and is essential for ensuring ecological validity. Here, intelligibility was measured using online testing for 69 young adult listeners in three listening conditions (i.e., quiet, speech-shaped noise, and hospital noise: 23 listeners per …

Neuromorphic Computing Using Electrostatic Mems Devices, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A continuous - time recurrent neural network ( CTRNN ) is described that exploits the nonlinear dynamics of micro electro - mechanical system ( MEMS ) devices to model a neuron in accordance with a neuron rate model that is the basis for dynamic field theory . Each MEMS device in the CTRNN is configured to simulate a neuron population by exploiting the characteristics of bi - stability and hysteresis inherent in certain MEMS device structures . In an embodiment , the MEMS device is a microbeam or cantilevered microbeam device that is excited with an alternating current ( AC …

Reducing Early-Age Shrinkage Cracks Of Bridge Decks And Rails, Soumitra Das, George Morcous, Jiong Hu

UNL Student Research Days Posters, Graduate

Early-age shrinkage cracking of concrete bridge decks and rails accelerates the penetration of water and chemicals which leads to reinforcement corrosion, delamination, and eventually spalling. All this results in shorter service life, road closure, and costly repair. Development of Low-cement concrete(LCC) mix to reduce early age shrinkage crack through aggregate grading optimization was done in this research work. This approach also reduces concrete cost ($15-$20/cyd) (15–25%) and its carbon footprint (≈15%).

Ahp Based Multi Criteria Decision Analysis Of Success Factors To Enhance Decision Making In Infrastructure Construction Projects, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei

Durham School of Architectural Engineering and Construction: Faculty Publications

The study presents analytical data-based multi-criteria approach of critical success factors of infrastructure construction projects analyzed in the Ethiopian construction industry. This multi-criteria technique helps to improve the decision capabilities and ultimate performance of construction processes in various low-income countries of the East African region. The aim of this paper is to establish a logical relationship and interdependencies of success-related factors for enhancing decision making for various project teams and identify priorities while taking into account all known construction organizational constraints. A structured hierarchical matrix was developed based on a pre-identified success-related factors, and initially evaluated by experienced professionals as …

Availability Heuristic In Construction Workforce Decision-Making Amid Covid-19 Pandemic: Empirical Evidence And Mitigation Strategy, Yunping Liang, Anil Baral, Mohsen Shahandashti, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

The decision-making situations of the construction workforce have been drastically altered since the outbreak of the Coronavirus 2019 (COVID-19) pandemic. The new situation, where decision-makers strive to promptly respond to the unprecedented crisis to sustain essential construction operations without compromising the safety and health of workers, implies the presence of an availability heuristic. An availability heuristic has the potential to bring unconscious, systematic errors to the decision-making process. This study creates a decision-making experiment to empirically examine the presence of an availability heuristic and the effectiveness of a corresponding mitigation strategy in construction workforce decision-making under COVID-19 uncertainties. The experiment …

Impact Of Covid-19 On The Diversity Of The Construction Workforce, Anil Baral, Yunping Liang, Mingshu Li, Marilyn Gonzalez, Mohsen Shahandashti, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

Construction industry employment has been severely impacted by the coronavirus (COVID-19) pandemic. This paper examines the impact of the COVID-19 pandemic in the US construction labor market. This study contributes to the state of knowledge by (1) revealing how the COVID-19 pandemic impacted construction employment across different demographic groups and geographic regions in the US, and (2) identifying vulnerable demographic groups (e.g., minorities, women, older workers) in the construction workforce that are disproportionally impacted by the pandemic. Employment data from the Current Population Survey and Current Employment Statistics (CES) programs, which are administered by the Bureau of Labor Statistics, are …

Tilt-Up Partially Composite Insulated Wall Panels, Marc Maguire, Salam Al-Rubaye

Durham School of Architectural Engineering and Construction: Faculty Publications

This research project was initiated to investigate the behavior of load-bearing concrete insulated wall panels for use in tilt-up construction. The primary objective was to understand the inelastic behavior of these panels so that engineers could perform a proper second-order analysis for combined axial and out-of-plane loading. Toward this aim, the Tilt-up Concrete Institute (TCA) and wythe connector suppliers Innstruct, Thermomass, HK Composites, Dayton Superior, and IconX, funded this study.

This report contains information related to testing of solid and partially composite insulated wall panels that integrated proprietary wythe connection systems. Using the information from these tests, a method to …

Challenges And Enabling Features Of Small And Medium Infrastructure Public-Private Partnerships (P3s): A Case Study Of The Us P3 Infrastructure Market, Yunping Liang, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

Purpose: In classical perspective, projects under a certain size are not feasible for P3. However, there is an emerging trend on using P3 to deliver projects that are frequently small to medium sized to meet ever-increasingly complex social needs, including enhancing lifecycle performance of existing facilities, designing and building for resilience and sustainability, ensuring cost effectiveness of public spending, and fostering innovation. In contrast with the increasing implementation, small and medium P3s, especially those in the United States, receive little attention in existing studies. This study aims at answering the question: in the context of the US, what features of …

Higher Sound Levels In K-12 Classrooms Correlate To Lower Math Achievement Scores, Laura Caroline Brill, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Sound levels from occupied classrooms have been gathered from 220 classrooms across four grade levels (3, 5, 8 and 11) over six school days each and processed with k-means clustering into speech and non-speech clusters. Three metrics describing the classroom acoustics, including the average daily A-weighted equivalent level for non-speech, the average daily difference between the A-weighted equivalent levels for speech and nonspeech (a signal to noise ratio), and the mid-frequency averaged reverberation time, were analyzed against classroom-aggregated standardized reading and math achievement test scores, while controlling for classroom demographics including socioeconomic status. Interactions between the metrics and demographics were …

The Effects Of The Visual Environment On K-12 Student Achievement, Michael Kuhlenengel, Iason Konstantzos, Clarence E. Waters

Durham School of Architectural Engineering and Construction: Faculty Publications

The varying indoor environments among educational buildings can have an impact on students’ ability to learn. This study looks at field data from 220 classrooms in the Midwest, United States, over a two-year period, to analyze the effects of the visual environment on student achievement. The visual environmental metrics considered within this scope include the three new view metrics introduced within the EN 17037 “Daylight of Buildings” standard (Horizontal Sight Angle, Outside Distance of View, and Number of View Layers), as well as standard daylight and electric lighting metrics, focusing on light availability and glare. To capture student achievement, math …

Simulation For A Mems-Based Ctrnn Ultra-Low Power Implementation Of Human Activity Recognition, Muhammad Emad-Ud-Din, Mohammad H. Hasan, Roozbeh Jafari, Siavash Pourkamali, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents an energy-efficient classification framework that performs human activity recognition (HAR). Typically, HAR classification tasks require a computational platform that includes a processor and memory along with sensors and their interfaces, all of which consume significant power. The presented framework employs microelectromechanical systems (MEMS) based Continuous Time Recurrent Neural Network (CTRNN) to performHAR tasks very efficiently. In a real physical implementation, we show that the MEMS-CTRNN nodes can perform computing while consuming power on a nano-watts scale compared to the micro-watts state-of-the-art hardware. We also confirm that this huge power reduction doesn’t come at the expense of reduced …

Framework To Develop Time- And Voltage-Dependent Building Load Profiles Using Polynomial Load Models, Andrew Parker, Mhd Anas Alkrch, Kevin James, Ahmad Almaghrebi, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

The power consumption of buildings over the course of each minute, hour, day and season plays a major role in how this load influences the Electric Power System voltage and frequency, and vice versa. This consumption is based on the building's load component types, efficiencies, and how they consume power and react to changes in real time. Due to this complexity, standard full-building load models are typically voltage-invariant. This paper proposes a novel framework to transform these voltage-invariant building load models into fully time- and voltage-dependent load profiles using available data on the voltage sensitivity of individual load components. While …

A Case Study To Quantify Variability In Building Load Profiles, Andrew Parker, Sam Moayedi, Kevin James, Dongming Peng, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

Recent technology development and penetration of advanced metering infrastructure (AMI), advanced building control systems, and the internet-of-things (IoT) in the built environment are providing detailed information on building operation, performance, and user's comfort and behavior. Building owners can obtain a wide range of energy consumption details at various levels of time granularity to augment their decisions as they manage the building operation and interact with the grid. AMI data are providing a new level of detail and visibility that may enhance building services and assets in the smart grid domain and make buildings inch closer to becoming a grid-interactive energy …

Evaluating Prediction Models Of Creep And Drying Shrinkage Of Self-Consolidating Concrete Containing Supplementary Cementitious Materials/Fillers, Micheal Asaad, George Morcous

Durham School of Architectural Engineering and Construction: Faculty Publications

Supplementary cementitious materials (SCMs) and fillers play an important role in enhancing the mechanical properties and durability of concrete. SCMs and fillers are commonly used in self-consolidating concrete (SCC) mixtures to also enhance their rheological properties. However, these additives could have significant effects on the viscoelastic properties of concrete. Existing models for predicting creep and drying shrinkage of concrete do not consider the effect of SCM/filler on the predicted values. This study evaluates existing creep and drying shrinkage models, including AASHTO LRFD, ACI209, CEB-FIP MC90-99, B3, and GL2000, for SCC mixtures with different SCMs/fillers. Forty SCC mixtures were proportioned for …

The Facility Infection Risk Estimator™: A Web Application Tool For Comparing Indoor Risk Mitigation Strategies By Estimating Airborne Transmission Risk, Marcel Harmon, Josephine Lau

Durham School of Architectural Engineering and Construction: Faculty Publications

The COVID-19 pandemic created needs for (a) estimating the existing airborne risk of infection from SARS-CoV-2 in existing facilities and new designs and (b) estimating and comparing the impacts of engineering and behavioural strategies for contextually reducing that risk. This paper presents the development of a web application to meet these needs, the Facility Infection Risk Estimator™, and its underlying Wells–Riley based model. The model specifically estimates (a) the removal efficiencies of various settling, ventilation, filtration and virus inactivation strategies and (b) the associated probability of infection, given the room physical parameters and number of individuals infected present with either …

Designing Gfrp-Reinforced Tilt-Up Wall Panels, Fray F. Pozo-Lora, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Tilt-up construction was effectively enabled on a wide scale in 1979, when the ACI committee 551 report on Tilt-up construction was published, the Recommended Tilt-Up Wall Design, aka, the Yellow Book and the subsequent ACI-SEASC Task, aka the Green Book, and another Tilt-up design and construction manual developed by the ACI in 1988. The Tilt-up Concrete Association was created in 1986 by a group of industry professionals who had the need of an organization dedicated to the industry. ACI 551 maintains a document outlining the standard practice for contemporary Tilt-up design and construction. The ACI 551 document does not consider …

Performance Evaluation Of A Prestressed Belitic Calcium Sulfoaluminate Cement (Bcsa) Concrete Bridge Girder, Nick Markosian, Raed Tawadrous, Mohammad Mastali, Robert J. Thomas, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Belitic calcium sulfoaluminate (BCSA) cement is a sustainable alternative to Portland cement that offers rapid setting characteristics that could accelerate throughput in precast concrete operations. BCSA cements have lower carbon footprint, embodied energy, and natural resource consumption than Portland cement. However, these benefits are not often utilized in structural members due to lack of specifications and perceived logistical challenges. This paper evaluates the performance of a full-scale precast, prestressed voided deck slab bridge girder made with BCSA cement concrete. The rapid-set properties of BCSA cement allowed the initial concrete compressive strength to reach the required 4300 psi release strength at …

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, Theses, 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 …

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 …

Forecasting The Construction Expenditure Cash Flow For Transportation Design-Build Projects With A Case-Based Reasoning Model, Yunping Liang, Baabak Ashuri, Mingshu Li

Durham School of Architectural Engineering and Construction: Faculty Publications

Accurately forecasting the construction expenditure cash flow of transportation projects is critical for state departments of transportation (state DOTs) to secure sufficient funding to cover their fiscal obligations throughout the project development timeline. However, there is no quantitative model to assist state DOTs in accurately forecasting expenditure cash flows for design-build projects. At the outset of awarding a typical design-build contract, the design has not been finalized to enable exact quantities for a detailed cost estimate. This issue represents a big difference between design-build and design-bid-build projects that makes estimating the project payouts more difficult for design-build projects. This research …

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 …