Engineering Commons^™

A Systematic Unified Approach For Addressing Temporal Instability In Road Safety Analysis, Kazi Redwan Shabab, Tanmoy Bhowmik, Mohamed H. Zaki, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

Multivariate models are widely employed for crash frequency analysis in traffic safety literature. In the context of analyzing data for multiple instances (such as years), it becomes essential to evaluate the stability of parameters over time. The current research proposes a novel approach, labelled the mixed spline indicator pooled model, that offers significant enhancement relative to current approaches employed for capturing temporal instability. The proposed approach entails carefully creating independent variables that allow us to measure parameter slope changes over time and can be easily integrated into existing methodological frameworks. The current research effort compares four multivariate model systems: year …

Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy

Civil and Environmental Engineering Faculty Publications and Presentations

Evacuation behavior models estimated using post-disaster surveys are not adequate to predict real-time dynamic population response as a hurricane unfolds. With the emergence of ubiquitous technology and devices in recent times, social media data with its higher spatio-temporal coverage has become a potential alternative for understanding evacuation behaviour during hurricanes. However, these data are often associated with selection bias and population representativeness issues. To that extent, the current study proposes a novel data fusion algorithm to combine heterogeneous data sources from transportation systems and social media, in a unified framework to understand and predict real-time population response during hurricanes. Specifically, …

Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot

Civil and Environmental Engineering Faculty Publications and Presentations

Our purpose was to test the hypothesis that ultrasonic cigarettes (u-cigarettes), which operate at relatively low temperatures, produce aerosols that are less harmful than heated-coil pod-style electronic cigarettes (e-cigarettes). The major chemicals in SURGE u-cigarette fluids and aerosols were quantified, their cytotoxicity and cellular effects were assessed, and a Margin of Exposure risk assessment was performed on chemicals in SURGE fluids. Four SURGE u-cigarette flavor variants ("Blueberry Ice," "Watermelon Ice," "Green Mint," and "Polar Mint") were evaluated. Flavor chemicals were quantified in fluids and aerosols using gas chromatography/mass spectrometry. Cytotoxicity and cell dynamics were assessed using the MTT assay, live-cell …

Early Detection Of Structural Damage In Uhpfrc Structures Through The Combination Of Acoustic Emission And Ultrasonic Stress Wave Monitoring, Numa Bertola, Thomas Schumacher, Ernst Niederleithinger, Eugen Brühwiler

Civil and Environmental Engineering Faculty Publications and Presentations

Ultra-High-Performance Fiber-Reinforced Cementitious Composite (UHPFRC) offers several advantages compared to concrete, notably due to the strain hardening behavior under tensile actions. Structures made of this composite material are lightweight and highly durable, thanks to the UHPFRC waterproofing quality. Nonetheless, the tensile behavior leads to a different cracking pattern than conventional concrete and is not fully understood yet. This paper presents a combined approach using both passive ultrasonic (US) stress wave (or acoustic emission) and active US stress wave monitoring to localize and quantify damage progression in a full-scale UHPFRC beam during experimental load testing. The proposed monitoring approach involves 24 …

Advanced Acoustic Emission-Based Shm For Concrete Structures: Real-Time, High-Precision Imaging Of Crack Geometry And Damage Sourcetype Using Moment Tensor Inversion, Seyyedmaalek Momeni, Thomas Schumacher, Lindsay Linzer, Brice Lecampion

Civil and Environmental Engineering Faculty Publications and Presentations

In this paper, we introduce a novel automated and high-precision acoustic emission (AE) monitoring algorithm and the software SIMORGH, which is suitable for structural health monitoring (SHM) of civil structures. Initially developed for laboratory-scale hydraulic fracture monitoring, this core software has been effectively scaled up to meter-level applications and is compatible with heterogeneous media such as concrete. It is designed to work with various standard data formats and is handles both trigger-based and continuous data. We present initial results from implementing this software in the AE monitoring of two 4.88-meter-long concrete beams in a laboratory setting, comparing it with manually …

Combined Passive And Active Ultrasonic Stress Wave Monitoring Of Concrete Structures: An Overview Of Data Analysis Techniques And Their Applications And Limitations, Thomas Schumacher, Numa Bertola, Niklas Epple, Eugen Bruehwiler, Ernst Niederleithinger

Civil and Environmental Engineering Faculty Publications and Presentations

Combined passive ultrasonic (US) stress wave [better known as acoustic emission (AE)] and active US stress wave monitoring has been shown to provide a more holistic picture of ongoing fracture processes, damage progression, as well as slowly occurring aging and degradation mechanisms in concrete structures. Traditionally, different data analysis techniques have been used to analyze the data generated from these two monitoring techniques. For passive US stress wave monitoring, waveform amplitudes, hit rates, source localization, and b-value analysis, among others, have been used to detect and locate cracking. On the other hand, amplitude tracking, magnitude squared coherence (MSC), and coda …

Processes For Depositing Functionalized Nanoparticles Upon A Substrate, Erik T. Thostenson, Thomas Schumacher

Civil and Environmental Engineering Faculty Publications and Presentations

Processes for depositing functionalized nanoparticles upon a non-conductive substrate are disclosed herein. The processes may include the step of aerosolizing one or more particles into suspension within a gas, each of the one or more particles comprising functionalized nanoparticles having an electric charge. The processes may include the step the step of attracting the one or more particles onto a non-conductive substrate by a static electric charge opposite of the electric charge, wherein at least portions of the non-conductive substrate are having the static electric charge. The processes may include the step of depositing the functionalized nanoparticles onto the non-conductive …

Investigation Of Piezocone Dissipation Test Interpretation In Clay Accounting For Vertical And Horizontal Porewater Pressure Dissipation With A Large Deformation Axisymmetric Penetration Model, Diane Moug, Andrew Huffman, Jason T. Dejong

Civil and Environmental Engineering Faculty Publications and Presentations

The piezocone (CPTu) dissipation test is used to characterize how the applied load from the penetrating cone is distributed between the soil and pore fluid during both penetrometer advancement and when penetration is paused. The coefficient of consolidation is often estimated from CPTu dissipation tests by interpreting the rate of excess porewater pressure (∆u) decay to static conditions during a pause in cone penetration. Most CPTu dissipation test interpretation methods are based on Terzaghi consolidation theory for ∆u dissipation at the cone shoulder (u₂ position) or cone face (u₁ position) and assume that radial ∆u dissipation dominates the …

Imaging Of Structural Timber Based On In Situ Radar And Ultrasonic Wave Measurements: A Review Of The State-Of-The-Art, Narges Pahnabi, Thomas Schumacher, Arijit Sinha

Civil and Environmental Engineering Faculty Publications and Presentations

With the rapidly growing interest in using structural timber, a need exists to inspect and assess these structures using non-destructive testing (NDT). This review article summarizes NDT methods for wood inspection. After an overview of the most important NDT methods currently used, a detailed review of Ground Penetrating Radar (GPR) and Ultrasonic Testing (UST) is presented. These two techniques can be applied in situ and produce useful visual representations for quantitative assessments and damage detection. With its commercial availability and portability, GPR can help rapidly identify critical features such as moisture, voids, and metal connectors in wood structures. UST, which …

An Adaptive Large Neighborhood Search For The Multi-Vehicle Profitable Tour Problem With Flexible Compartments And Mandatory Customers, Vincent F. Yu, Nabila Yuraisyah Salsabila, Aldy Gunawan, Anggun Nurfitriani Handoko

Civil and Environmental Engineering Faculty Publications and Presentations

The home-refill delivery system is a business model that addresses the concerns of plastic waste and its impact on the environment. It allows customers to pick up their household goods at their doorsteps and refill them into their own containers. However, the difficulty in accessing customers’ locations and product consolidations are undeniable challenges. To overcome these issues, we introduce a new variant of the Profitable Tour Problem, named the multi-vehicle profitable tour problem with flexible compartments and mandatory customers (MVPTPFC-MC). The objective is to maximize the difference between the total collected profit and the traveling cost. We model the proposed …

On The Feasibility Of Ultrasonic Full Waveform Evaluation With Changing Testing Conditions For The Quality Control Of Manufacturing Parts, Simon Schmid, Thomas Schumacher, Christian U. Grosse

Civil and Environmental Engineering Faculty Publications and Presentations

Fast volumetric non-destructive testing methods are needed, especially for quality control in manufacturing lines. Ultrasonic testing with full waveform evaluation is a promising method for this. However, changes in coupling conditions or environmental factors can significantly alter the ultrasound signal, sometimes more than actual defects. This study investigates the effect of various factors on the ultrasound signal based on a Monte Carlo study with wavefield simulations. The test specimens comprise aluminium plates with holes of varying sizes and positions. Using both experimental as well as simulated data, the performance of two commonly used comparison metrics, namely the R2 score and …

Implementation Of A Realistic Artificial Data Generator For Crash Data Generation, Lauren Hoover, Md. Istiak Jahan, Tanmoy Bhowmik, Sudipta Dey Tirtha, Karthik C. Konduri, John Ivan, Kai Wang, Shanshan Zhao, Joshua Auld, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

In this paper, a framework is outlined to generate realistic artificial data (RAD) as a tool for comparing different models developed for safety analysis. The primary focus of transportation safety analysis is on identifying and quantifying the influence of factors contributing to traffic crash occurrence and its consequences. The current framework of comparing model structures using only observed data has limitations. With observed data, it is not possible to know how well the models mimic the true relationship between the dependent and independent variables. Further, real datasets do not allow researchers to evaluate the model performance for different levels of …

Accommodating Spatio-Temporal Dependency In Airline Demand Modeling, Sudipta Dey Tirtha, Tanmoy Bhowmik, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

The objective of the current study is to examine monthly air passenger departures at the airport level considering spatial interactions between airports. In this study, we develop a novel spatial grouped generalized ordered probit (SGGOP) model system of monthly air passenger departures at the airport level. Specifically, we estimate two variants of spatial models including spatial lag model and spatial error model. In the presence of repeated demand measures for the airports, we also consider temporal variations of spatial correlation effects among proximally located airports by employing space and time-based weight matrix. The proposed model is estimated using monthly air …

Contributing Factors To Right-Turn Crash Severity At Signalized Intersections: An Application Of Econometric Modeling, Hisham Jashami, Jason C. Anderson, Hameed Mohammed, Douglas P. Cobb, David Hurwitz

Civil and Environmental Engineering Faculty Publications and Presentations

Motorists are required to interact with both roadway infrastructure and various users. The complexity of the driving task in certain scenarios can influence the frequency and severity of crashes. Turning vehicles at intersections, for example, pose a collision risk for both motorized and non-motorized road users. The primary goal of this paper is to investigate the underlying factors which contribute to right-turn crashes at signalized intersections. Five years of crash data across Oregon were collected. A random parameters binary logit model was developed to predict the likelihood of whether a crash resulted in an injury or fatality. It was found …

Nonlinear Interactions Of Sea‐Level Rise And Storm Tide Alter Extreme Coastal Water Levels: How And Why?, H. Moftakhari, D. F. Muñoz, A. Akbari Asanjan, A. Aghakouchak, Hamid Moradkhani, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Sea-level rise (SLR) increasingly threatens coastal communities around the world. However, not all coastal communities are equally threatened, and realistic estimation of hazard is difficult. Understanding SLR impacts on extreme sea level is challenging due to interactions between multiple tidal and non-tidal flood drivers. We here use global hourly tidal data to show how and why tides and surges interact with mean sea level (MSL) fluctuations. At most locations around the world, the amplitude of at least one tidal constituent and/or amplitude of non-tidal residual have changed in response to MSL variation over the past few decades. In 37% of …

Sea Level Rise And The Drivers Of Daily Water Levels In The Sacramento-San Joaquin Delta, H. Baranes, Steven Dykstra, D. A. Jay, S. A. Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Water levels in deltas and estuaries vary on multiple timescales due to coastal, hydrologic, meteorologic, geologic, and anthropogenic factors. These diverse factors increase the uncertainty of, and may bias, relative sea level rise (RSLR) estimates. Here, we evaluate RSLR in San Francisco Bay and the Sacramento-San Joaquin Delta, USA by applying a physics-based, nonlinear regression to 50 tide gauges that determines the spatially varying controls on daily mean water level for water years 2004–2022. Results show that elevated river flow and pumping (99th percentile) raise water level up to 6 m and lower it up to 0.35 m, respectively, and …

Shallow‑Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David A. Jay, Heida Diefenderfer, Stefan Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Decreases in shallow-water habitat area (SWHA) in the Lower Columbia River and Estuary (LCRE) have adversely affected salmonid populations. We investigate the causes by hindcasting SWHA from 1928 to 2004, system-wide, based on daily higher high water (HHW) and system hypsometry. Physics-based regression models are used to represent HHW along the system as a function of river inflow, tides, and coastal processes, and hypsometry is used to estimate the associated SWHA. Scenario modeling is employed to attribute SWHA losses to levees, flow regulation, diversion, navigational development, and climate-induced hydrologic change, for subsidence scenarios of up to 2 m, and for …

Localization And Shape Determination Of A Hidden Corridor In The Great Pyramid Of Giza Using Non-Destructive Testing, Mohamed Elkarmoty, Johannes Rupfle, Khalid Helal, Mohamed Sholqamy, Mohamed Fath-Elbab, Jochen Kollofrath, Thomas Schumacher, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

Built over 4500 years ago, the Great Pyramid of Giza, Egypt, is the only remaining structure of the Wonders of the Ancient World as described by the ancient Greek historian Herodotus. Despite this long existence, only recently has modern science and technology been employed to study this massive stone structure. Cosmic-ray muon radiography throughout the ScanPyramids project has detected a large void above the Grand Gallery of the Great Pyramid and a smaller unidentified void behind the so-called Chevron. The Chevron is an assembly of four large limestone blocks arranged in the shape of two inverted downward open angles. Guided …

Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel, Alistair Leverett, Anne Borland, Emma Inge, Samantha Hartzell

Civil and Environmental Engineering Faculty Publications and Presentations

Crassulacean Acid Metabolism (CAM) is a photosynthetic adaptation found in at least 38 plant families. Typically, the anatomy of CAM plants is characterised by large photosynthetic cells and a low percentage of leaf volume comprised of internal air space (% IAS). It has been suggested that reduced mesophyll conductance (g_m) arising from low % IAS benefits CAM plants by preventing the movement of CO₂ out of cells and ultimately minimising leakage of CO₂ from leaves into the atmosphere during day-time decarboxylation. Here, we propose that low % IAS does not provide any adaptive benefit to …

Modeling Cyanotoxin Production, Fate, And Transport In Surface Water Bodies Using Ce-Qual-W2, Bernadel Rose Hintz Garstecki, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Cyanobacteria are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change are expected to increase the occurrence of cyanobacteria, and it is vital that we protect our drinking water supplies and natural water resources. Modeling the production, fate, and transport of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. The research provided here offers an overview of some of the main cyanotoxins of concern and presents preliminary models for the transport and …

Impacts Of A Cascadia Subduction Zone Earthquake On Water Levels And Wetlands Of The Lower Columbia River And Estuary, M. W. Brand, Heida Diefenderfer, J. E. O’Connor, Amy B. Borde, D. A. Jay, Aqeel Al-Bahadily, M. Mckeon, S. A. Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Subsidence after a subduction zone earthquake can cause major changes in estuarine bathymetry. Here, we quantify the impacts of earthquake-induced subsidence on hydrodynamics and habitat distributions in a major system, the lower Columbia River Estuary, using a hydrodynamic and habitat model. Model results indicate that coseismic subsidence increases tidal range, with the smallest changes at the coast and a maximum increase of ∼10% in a region of topographic convergence. All modeled scenarios reduce intertidal habitat by 24%–25% and shifts ∼93% of estuarine wetlands to lower-elevation habitat bands. Incorporating dynamic effects of tidal change from subsidence yields higher estimates of remaining …

Damage Tracking In Laboratory Reinforced Concrete Bridge Columns Under Reverse-Cyclic Loading Using Fusion-Based Imaging, Sina Mehdinia, A K M Golam Murtuz, Thomas Schumacher, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

Fusion-based imaging using ground-penetrating radar (GPR) and ultrasonic echo array (UEA) was employed to track damage progression in the columns of two full-scale reinforced concrete (RC) bridge column-footing subassembly laboratory specimens. The specimens had different lap-splice detailing and were subjected to reverse-cyclic lateral loading simulating a subduction zone earthquake. GPR and UEA scans were performed on the east and west faces of the columns at select ductility levels. Reconstructed images were obtained using the extended total focusing method (XTFM) and fused using a wavelet-based technique. Composite images of each column's interior were created by merging the images from both sides. …

Global Water Level Variability Observed After The Hunga Tonga-Hunga Ha’Apai Volcanic Tsunami Of 2022, Adam Thomas Devlin, David A. Jay, Stefan Talke, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

The eruption of the Hunga Tonga-Hunga Ha'apai volcano on 15 January 2022 provided a rare opportunity to understand global tsunami impacts of explosive volcanism and to evaluate future hazards, including dangers from “volcanic meteotsunamis” (VMTs) induced by the atmospheric shock waves that followed the eruption. The propagation of the volcanic and marine tsunamis was analyzed using globally distributed 1 min measurements of air pressure and water level (WL) (from both tide gauges and deep-water buoys). The marine tsunami propagated primarily throughout the Pacific, reaching nearly 2 m at some locations, though most Pacific locations recorded maximums lower than 1 m. …

Warming Of The Columbia River, 1853 To 2018, Malia Hanae Scott, Stefan Talke, David Jay, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Water temperature is a critical ecological indicator; however, few studies have statistically modeled century-scale trends in riverine or estuarine water temperature, or their cause. Here, we recover, digitize, and analyze archival temperature measurements from the 1850s onward to investigate how and why water temperatures in the lower Columbia River are changing. To infill data gaps and explore changes, we develop regression models of daily historical Columbia River water temperature using time-lagged river flow and air temperature as the independent variables. Models were developed for 3 time periods (mid-19 th , mid-20 th , and early 21 st century), using archival …

Numerical Modeling Of A Pile-Supported Wharf Subjected To Liquefaction-Induced Lateral Ground Deformations, Milad Souri, Arash Khosravifar, Stephen Dickenson, Nason Mccullough, Scott Schlechter

Civil and Environmental Engineering Faculty Publications and Presentations

Fully-coupled nonlinear dynamic analysis is increasingly used for assessing the seismic performance of pile-supported wharf structures subjected to liquefaction-induced lateral ground deformations. Several numerical challenges exist for analysis of this highly nonlinear soil-structure interaction, which require robust, yet practical, solutions that are validated with experimental data. This study presents a numerical model of a pile-supported wharf and evaluates the applicability of a soil constitutive model, and modeling assumptions and methods by using recorded data from a well-instrumented, large-scale centrifuge test. The objectives of this study include: (a) evaluating the performance of a recently developed pressure-dependent multi-yield surface constitutive soil model …

Driver And Bicyclist Comprehension Of Blue Light Detection Confirmation Systems, Douglas P. Cobb, Hisham Jashami, Christopher Monsere, Sirisha Kothuri, David S. Hurwitz

Civil and Environmental Engineering Faculty Publications and Presentations

This study analyzed motorist and bicyclist understanding and preference of positive confirmation of detection of a bicycle by the traffic signal infrastructure using a blue light detection confirmation (BLDC). The research analyzed results of an online survey of 1,123 respondents and intercept survey of 337 respondents. The study initially found that participants of the survey did not understand the meaning of the blue light itself, but comprehension of the system rose from 40% to 50% when supplemental signs were used. Respondents overwhelmingly indicated that they preferred the sign option that included symbols, text, and a representation of the blue light, …

Dissecting Succulence: Crassulacean Acid Metabolism And Hydraulic Capacitance Are Independent Adaptations In Clusia Leaves, Alistair Leverett, Samantha Hartzell, Klaus Winter, Milton Garcia, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

Succulence is found across the world as an adaptation to water-limited niches. The fleshy organs of succulent plants develop via enlarged photosynthetic chlorenchyma and/or achlorophyllous water storage hydrenchyma cells. The precise mechanism by which anatomical traits contribute to drought tolerance is unclear, as the effect of succulence is multifaceted. Large cells are believed to provide space for nocturnal storage of malic acid fixed by crassulacean acid metabolism (CAM), whilst also buffering water potentials by elevating hydraulic capacitance (CFT). The effect of CAM and elevated CFT on growth and water conservation have not been compared, despite the assumption that these adaptations …

Damage Detection In Reinforced Concrete Member Using Local Time-Frequency Transform Applied To Vibration Measurements, Ning Liu, Thomas Schumacher, Yan Li, Lina Xu, Bo Wang

Civil and Environmental Engineering Faculty Publications and Presentations

Signal processing and analysis of structural vibration measurements are key components of structural damage detection (SDD) in structural health monitoring (SHM). The goal of signal processing is to extract subtle changes in the measured signals, which can be used to infer changes in structural parameters and damage. Time-frequency analysis is one of the most popular characterization methods for studying non-stationary vibration signals. In this article, the local time-frequency transform (LTFT) is applied and evaluated to calculate the time-domain signals because of its excellent time-frequency energy distribution properties. The LTFT matches the input data by the Fourier basis in an inverse …

Exploratory Analysis Of Factors Affecting Home Delivery Returns, Michael Bronson, Miguel Figliozzi, Ali Riahi Samani, Sabya Mishra

Civil and Environmental Engineering Faculty Publications and Presentations

E-commerce and house deliveries have experienced a rapid growth in the last two decades. The return of online shopping products is an undesirable side effect of online shopping that has not been properly studied in the transportation literature. Utilizing binary logit models, this research answers two novel research questions focusing on the online shopping channel: (i) What household characteristics are associated with a higher or lower propensity to return online purchases? and (ii) What type of products contribute to positive return delivery rates? To answer these questions models are developed using data collected from a household online survey of e-commerce …

Eugenol, Menthol And Other Flavour Chemicals In Kreteks And ‘White’ Cigarettes Purchased In Indonesia, Joanna Cohen, Beladenta Amalia, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow

Civil and Environmental Engineering Faculty Publications and Presentations

Background Flavoured tobacco products are not restricted in Indonesia, a country with about 68 million adults who smoke. Most use clove-mixed tobacco cigarettes (‘kreteks’); non-clove (‘white’) cigarettes are also available. Although the use of flavour chemicals has been identified by WHO as promoting tobacco use, little has been reported for Indonesia about the levels of flavourants in either kreteks or ‘white cigarettes’.

Methods 22 kretek brand variants and nine ‘white’ cigarette brand variants were purchased in Indonesia during 2021/2022; one of the kretek packs contained three colour-coded variants, giving a total sample number of 24 for the kreteks. Chemical analyses …