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Full-Text Articles in Engineering

Processes For Depositing Functionalized Nanoparticles Upon A Substrate, Erik T. Thostenson, Thomas Schumacher Jun 2024

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 …


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 Jun 2024

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 …


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 Jun 2024

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 …


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 Jun 2024

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 …


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 May 2024

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 May 2024

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 May 2024

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 Apr 2024

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 …


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 Mar 2024

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 …


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 Mar 2024

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 …