Construction Engineering and Management Commons^™

Construction Project Administration: Course Portfolio, Andre Messner

UNL Faculty Course Portfolios

This portfolio presents a structured framework for the design and implementation of a construction project administration course within a Construction Management program. Emphasis is placed on aligning student learning objectives, instructional strategies, and assessment methods with current industry expectations and professional standards. The course is intentionally designed to bridge the gap between theoretical knowledge and practical application by incorporating real-world scenarios, collaborative learning environments, and experiential activities that mirror industry practices.

In addition to outlining the course structure, this paper examines the pedagogical foundations that support student-centered learning, including constructivism, scaffolding, and project-based learning. These approaches are used to foster …

Exploring Determinants Of Value For Money And Bundling Effects On Public–Private Partnership Projects: A Data-Driven Empirical Study, Gaurav Khadka

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Public–private partnerships (P3s) are widely used to deliver public infrastructure, yet current understanding of what drives variation in Value for Money (VfM) and the effectiveness of project delivery strategies such as bundling remains largely conceptual and grounded in perception-based evidence. Consequently, governments lack empirically validated guidance on which project, financial, and macroeconomic conditions meaningfully influence VfM outcomes and whether bundling improves project performance within the P3 context. This study addresses these gaps through an integrated analysis of 180 Canadian P3 infrastructure projects (1992–2020), one of the most comprehensive datasets of realized VfM internationally, incorporating project characteristics, financial arrangements, and macroeconomic …

Large-Scale Experimental Study On The Impact Of Air Cleaning & Ventilation On Indoor Air Quality And Student Illness-Related Absenteeism, Daud Nosham

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This large-scale randomized experimental field study investigated the effect of portable air purifiers (PAPs) on classroom’s air quality and student’s illness related absenteeism. PAPs were installed in 317 classrooms from various school districts located in Eastern Nebraska. The classrooms were randomly assigned into four conditions: three treatment conditions (T1, T2 & T3) and one control condition (device without any filter). T1 was equipped with HEPA filters, T2 added Activated Carbon (AC) layer to HEPA, and T3 further integrated Germicidal Ultraviolet (GUV) alongside HEPA and AC filters. The measured variables were carbon dioxide (CO2), fine particles (PN2.5) and coarse particles (PNcoarse), …

Development And Implementation Of A Vector-Quantized Transformer Autoencoder For Monitoring Bicycle Road Conditions, Kewei Ren

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Adviser: Chun-Hsing Ho

The long-term, sustainable assessment of bicycle road conditions is essential for ensuring cyclist safety and promoting equitable infrastructure management. While traditional detection methods based on manual thresholds have demonstrated some effectiveness, they carry limitations due to the diversity of pavement materials, cyclist behaviors, and sensor platforms. Although recent advances in deep learning offer promising alternatives, established techniques are primarily applied to highway anomaly detection and are rarely adapted for bicycle roads. Furthermore, most related studies lack clear definitions for anomalies and transparent annotation procedures, resulting in a shortage of effective datasets and detection methods specifically for bicycle …

Feasibility Of Using Recycled Waste Plastic In Concrete Pavements In Nebraska, Amasi Hajahja

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Waste plastic (WP) is a growing environmental concern due to its non-biodegradable nature, large-scale production, and harmful impact on natural resources. With nearly 75% of WP in the United States ending up in landfills, effective recycling strategies are urgently needed. In parallel, the limited availability of natural aggregates highlights the need for alternative materials in concrete construction. This study investigates the feasibility of using recycled waste plastic (RWP) in concrete mixtures, both as aggregates and fibers for rigid pavement applications in Nebraska. Concrete mixtures were prepared by partially replacing natural fine aggregates with recycled plastic aggregates (RPA) at replacement levels …

Robot-Integrated 4d Building Information Modeling (4d Bim): Framework For Planning Safe Autonomous Construction Operations In Dynamic Environments, Hafiz Oyedimeji Oyediran

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In the construction industry, the use of autonomous robots is considered a solution to overcome the heavy reliance on human workers to perform repetitive, strenuous, and hazardous tasks. While these robots offer the advantage of autonomous operation, ensuring their safe and efficient integration within construction sites requires precise planning. Such planning must account for the varying project complexities such as scope, site layout, tasks, timelines, existence of human workers, and other spatiotemporal conditions of the construction site. Currently, there are no methods to safely plan autonomous robot operations considering these factors within the overarching construction planning process. Thus, autonomous robots …

Framework For Integrating Industry Knowledge Into A Large Language Model To Assist Construction Cost Estimation, Prashnna Ghimire

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The construction industry generates a large amount of data across projects produced by digital devices, tools, and methods, and this volume is rapidly increasing. However, the industry lags behind in adopting data-driven technologies. On the other hand, the rapid advancement of generative AI (GenAI) in recent years, especially state-of-the-art large language models (LLMs), shows great potential and has been increasingly adopted in many industries; however, the construction industry is behind in adoption. While academic studies have proposed various machine learning applications for construction, industry implementation has lagged due to a disconnect between these proof-of-concept developments and practical industry needs. Also, …

Analyzing Reciprocating Piston Expander Performance In Small-Scale Caes Considering Expansion Mismatch And Residual Mass Losses, Mehrdad Poursadegh

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Energy storage (ES) has become an essential element of modern energy systems, particularly with the rapid growth of renewable energy sources. While these sources are central to global decarbonization efforts, their intermittent nature creates significant challenges for both grid operators and end users. To address these challenges, a wide range of storage technologies have been developed ranging from large utility-scale to small behind-the-meter units. Among these, Compressed Air Energy Storage (CAES) stands out for its long lifespan, low storage cost per unit of energy, and ability to provide both electricity and thermal energy. However, small- and micro-scale CAES systems, unlike …

Investigation Of Faults In Air-Conditioning Systems In Commercial Buildings: Occurrence, Diagnostic Validation, And Energy Impacts, Yuxuan Chen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In commercial buildings, fault detection and diagnosis (FDD) tools have been developed for detecting and diagnosing faults in building systems, which can provide useful information regarding fault locations and potential causes of faults, so that building operators and facility staff can be notified in time and quickly respond as problems arise. Nowadays, there are many commercial FDD tools available in the market, and these tools have been widely adopted in large- and medium-scale commercial buildings in the United States. Several studies have demonstrated the energy saving potential with the use of FDD in commercial HVAC systems, and one critical aspect …

Development Of A Rule-Based Monitoring System For Autonomous Heavy Equipment Safety, Amirpooya Shirazi

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Roadway construction work zones are constantly exposed to interactions among construction equipment, workers, and vehicles. Furthermore, ensuring safety in these areas is considered a challenging task due to the complexity of the environment. As shown in the rising trend of fatal accidents in roadway work zones, current OSHA regulations in construction safety are insufficient in effectively detecting unsafe situations and mitigating the risks. Furthermore, best practices, such as internal traffic control planning (ITCP), exhibit critical limitations requiring continuous monitoring of active work zones as well as adjustments to the site coordination plans due to the dynamic nature of work zone …

Meta-Analysis Of Insulated Concrete Wall Panel Design Methods For Shear And Flexure Behavior, Maryam Al-Bayati

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

Insulated Concrete wall panels have been designed and constructed since the early 1950s with various shear ties, dimensions, and methods; nonetheless, thermal bridging and rational design are still a concern. Many companies have recently developed plastic connectors that have gradually replaced solid concrete sections and steel connectors due to their superior thermal efficiency and strength. However, there is no generally accepted method for predicting the behavior of sandwich wall panels in structural engineering practice or codes, but many methods have been used since the early 1920. This study aims to evaluate the accuracy of current methods for predicting the flexural …

Development Of Reduced Cementitious Materials Concrete (Rcmc) Mixtures For Bridge Decks And Rails, Soumitra Das

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Right after construction, drying shrinkage of restrained concrete bridge decks and rails causes early-age cracking that eventually leads to delamination and spalling of concrete due to insertion of water and chemicals, and corrosion of reinforcing steel. The main objective of this research is to control early-age shrinkage cracking by reducing cementitious material content in the bridge deck and rail concrete mixtures. Several reduced cementitious materials concrete (RCMC) mixtures were developed by optimizing aggregate particle packing and conducting overall performance evaluation. This evaluation was carried out in three phases: The first phase investigated the feasibility of new RCMC mixtures by testing …

Toward Low Carbon Footprint And Lightweight Masonry Alkali-Activated Material, Zina Ebrahim, Mohammad Mastali, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

The portland cement concrete industry and the masonry industry are undergoing changes in response to skilled labor shortages and concerns over climate and pollution. There may be interest from parts of the industry in lower carbon footprint and lightweight masonry products. Toward this aim, the use of hemp shiv--the woody core of the hemp plant--in alkali-activated concrete was investigated herein and shown to have a wide range of impacts on the hardened state characteristics of a material suitable for structural concrete masonry units (CMUs) in accordance with ASTM C90 requirements. Hemp shiv is well known for its use in hempcrete, …

Single-Pass Inline Pipeline 3d Reconstruction Using Depth Camera Array, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

A novel inline inspection (ILI) approach using depth cameras array (DCA) is introduced to create high-fidelity, dense 3D pipeline models. A new camera calibration method is introduced to register the color and the depth information of the cameras into a unified pipe model. By incorporating the calibration outcomes into a robust camera motion estimation approach, dense and complete 3D pipe surface reconstruction is achieved by using only the inline image data collected by a self-powered ILI rover in a single pass through a straight pipeline. The outcomes of the laboratory experiments demonstrate one-millimeter geometrical accuracy and 0.1-pixel photometric accuracy. …

Repair And Strengthening Of Concrete Bridges Using Ultra-High-Performance Concrete (Uhpc), Antony Kodsy

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Reinforced/Prestressed concrete bridges are subjected to environmental effects that cause premature deterioration and require structural repair and strengthening during their service life. Currently 42% of bridges in the United States are at least 50 years old, and 7.5% of them are structurally deficient and need to be repaired/strengthened. Recently, new repair and strengthening techniques using Ultra-High-Performance concrete (UHPC) have shown a great potential with respect to performance, economy, and speed. UHPC is a new class of concrete that has mechanical and durability properties that are far superior to those of conventional concrete (CC). In addition, UHPC offers several advantages compared …

Using Cost Simulation And Computer Vision To Inform Probabilistic Cost Estimates, Shu Jing Ding

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Cost estimating is a critical task in the construction process. Building cost estimates using historical data from previously performed projects have long been recognized as one of the better methods to generate precise construction bids. However, the cost and productivity data are typically gathered at the summary level for cost-control purposes. The possible ranges of production rates and costs associated with the construction activities lack accuracy and comprehensiveness. In turn, the robustness of cost estimates is minimal. Thus, this study proposes exploring a range of cost and productivity data to better inform potential outcomes of cost estimates by using probabilistic …

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%).

Semi Real-Time Detection Of Subsurface Consolidation Defects During Concrete Curing Stage, Chongsheng Cheng, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Subsurface consolidation defect is a common issue in concrete pavement construction, and the hidden defects often require costly repairs after project delivery. Therefore, being able to identify this type of defect during construction will enable contractor to conduct quick repairs to avoid costly post-construction rework. In this paper a semi real-time detection approach using infrared thermography is introduced. The developed approach utilizes the hydration heat during curing time to identify the subsurface voids based on the regional temperature contrast. Experimental studies were conducted using artificial void-defect in different sizes and depths. The thermographic analysis is employed to locate the void-defects …

Exploration Of The Sludge Biodiesel Pathway, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wastewater sludge is an overlooked source of fat, oil, and grease (FOG) that could be converted into biodiesel. The United States produces about 8 million tons of sludge per year. The disposal cost for this amount of sludge is about 2 billion US dollars. The widespread availability and low cost of sludge compared to other biodiesel raw materials make it an economical choice for a renewable fuel. Using sludge as a raw material can produce 25 to 30 mg per gram of fatty acid methyl ester (FAME); the main component of biodiesel. Sludge biodiesel has the potential of transforming a …

Ultra-High Performance Concrete (Uhpc) Deck-To-Girder Connection For Accelerated Bridge Construction, Mostafa Abo El-Khier

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Precast concrete deck systems have been successfully used for Accelerated Bridge Construction. In most systems, special deck-to-girder connections are designed to achieve structurally composite sections. These connections require tight production/erection tolerances that complicate deck and girder fabrication and compromise the economics of these systems. This study presents a new precast concrete deck-to-girder connection that takes advantage of the excellent mechanical, workability, and durability properties of ultra-high performance concrete (UHPC) to simplify precast concrete deck and girder fabrication and erection. Typical girder shear reinforcement is terminated below the soffit of deck panels to eliminate any conflicts with deck reinforcement and relax …

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 …

Quality Control In Concrete Pavement: Early Detection Of Near-Surface Honeycombing With Gpr, Theresa Mccabe

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

This thesis presents utilization of Ground Penetrating Radar (GPR) for the assessment of highway pavements to gain a better understanding of this NDE method’s capabilities in terms of early detection of consolidation-caused air voids in brittle materials. The objectives are to first, determine the earliest time during the dormant, setting, and early hardening periods of concrete’s set that GPR can be used to detect shallow air voids. Secondly, the change in dielectric constant will be tracked over the first 24 hours of concrete setting in order to quantify the impact of the dielectric constant assumptions in early detection. Two different …

Automatic Delamination Segmentation For Bridge Deck Based On Encoder-Decoder Deep Learning Through Uav-Based Thermography, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Concrete deck delamination often demonstrates strong variations in size, shape, and temperature distribution under the influences of outdoor weather conditions. The strong variations create challenges for pure analytical solutions in infrared image segmentation of delaminated areas. The recently developed supervised deep learning approach demonstrated the potentials in achieving automatic segmentation of RGB images. However, its effectiveness in segmenting thermal images remains under-explored. The main challenge lies in the development of specific models and the generation of a large range of labeled infrared images for training. To address this challenge, a customized deep learning model based on encoder-decoder architecture is proposed …

Evaluation Of The Dynamic Behavior Of Steel Staircases With Concrete Filled Pan Treads, Tyler Sondag

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

Vibration serviceability of staircases has been a growing challenge for structural engineers due to changing materials and structural forms. In order to prevent or correct serviceability problems due to structural vibrations, structural engineers should be able to predict the dynamic performance of a staircase structure. However, there are few technical guides available for designing steel staircases, and the ones that do exist are often limited in their applications. Currently, there is a lack of research on staircases that are less prone to vibrations, such as staircases with concrete filled pans that are composed of face and wall stringers. Therefore, the …

Evaluation Of An Interview-Based Internship Class In The Construction Management Curriculum: A Case Study Of The University Of Nebraska-Lincoln, Ali Karji, Stuart Bernstein, Mohammadsoroush Tafazzoli, Arash Arash Taghinezhad, Arefeh Mohammadi

Department of Construction Engineering and Management: Faculty Publications

Internships have been shown to be impactful tools to connect students’ learning in academia with real-world industrial needs. To help the students to get more out of their internship experience, some universities provide a summer internship class in which students do class assignments based on their experiences during their internship. There have been numerous studies on the benefits of internships. However, the benefits of a potential internship class for students in construction management (CM) programs at universities have not yet been investigated. This paper demonstrates the structure of an interview-based internship class and investigates its effectiveness. We have focused on …

The Application Of Gray-Scale Level-Set Method In Segmentation Of Concrete Deck Delamination Using Infrared Images, Chongsheng Cheng, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Conventional nondestructive delamination detection of concrete pavements through thermography is often based on temperature contrasts between delaminated and sound areas. Non-uniform backgrounds caused by the environmental conditions are often challenging for contrast-based methods to robustly differentiate the delaminated areas from the sound areas. Instead of focusing on the temperature contrast, this study proposes a temperature gradient-based level set method (LSM) to detect boundaries for delamination segmentations. A modified edge indicator function is developed to represent the normalized temperature gradient of a thermal image. The experimental study was conducted to evaluate its applicability and stability for boundary detection in terms of …

A Co-Optimal Coverage Path Planning Method For Aerial Scanning Of Complex Structures, Zhexiong Shang, Justin Bradley, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

The utilization of unmanned aerial vehicles (UAVs) in survey and inspection of civil infrastructure has been growing rapidly. However, computationally efficient solvers that find optimal flight paths while ensuring high-quality data acquisition of the complete 3D structure remains a difficult problem. Existing solvers typically prioritize efficient flight paths, or coverage, or reducing computational complexity of the algorithm – but these objectives are not co-optimized holistically. In this work we introduce a co-optimal coverage path planning (CCPP) method that simultaneously co-optimizes the UAV path, the quality of the captured images, and reducing computational complexity of the solver all while adhering to …

Bridge Deck Delamination Segmentation Based On Aerial Thermography Through Regularized Grayscale Morphological Reconstruction And Gradient Statistics, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Environmental and surface texture-induced temperature variation across the bridge deck is a major source of errors in delamination detection through thermography. This type of external noise poises a significant challenge for conventional quantitative methods such as global thresholding and k-means clustering. An iterative top-down approach is proposed for delamination segmentation based on grayscale morphological reconstruction. A weight-decay function was used to regularize the reconstruction for regional maxima extraction. The mean and coefficient of variation of temperature gradient estimated from delamination boundaries were used for discrimination. The proposed approach was tested on a lab experiment and an in-service bridge deck. The …

Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure, Chongsheng Cheng, Ri Na, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Despite decades of efforts using thermography to detect delamination in concrete decks, challenges still exist in removing environmental noise from thermal images. The performance of conventional temperature-contrast approaches can be significantly limited by environment-induced non-uniform temperature distribution across imaging spaces. Time-series based methodologies were found robust to spatial temperature non-uniformity but requires extended period to collect data. A new empirical image filtering method is introduced in this paper to enhance the delamination detection using blob detection method that originated from computer vison. The proposed method employs a Laplacian of Gaussian filter to achieve multi-scale detection of abnormal thermal patterns by …

The Impact Of Extreme Virtual Elevation Above Grade On Construction Workers' Physiological Responses, Physical Responses, And Task Performance, Mahmoud Habibnezhad

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

On average, in every two work hours, one person dies from work-related injuries at construction sites. Most incidents are due to falling from elevated surfaces. Slips, trips, and loss of balance are the main causes. Studies suggest that instigating visual mismatch and physiological changes are among the most important reasons behind falling from narrow elevated surfaces. By using advanced virtual reality models, this dissertation aims to highlight some of the possible effects of a destabilizing environment (i.e., elevation above grade) on workers’ physiological responses and task performance. More specifically, this dissertation strives to find potential effects of elevation above grade …