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Articles 1921 - 1950 of 11222

Full-Text Articles in Engineering

Nebraska Summary: S1160 John Deere 6195m, Nebraska Tractor Test Lab Jan 2019

Nebraska Summary: S1160 John Deere 6195m, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Wearable Devices For Single Cell Sensing And Transfection, Lingqian Chang, Yu-Chieh Wang, Faheem Ershad, Ruiguo Yang, Cunjiang Yu, Yubo Fan Jan 2019

Wearable Devices For Single Cell Sensing And Transfection, Lingqian Chang, Yu-Chieh Wang, Faheem Ershad, Ruiguo Yang, Cunjiang Yu, Yubo Fan

Department of Mechanical and Materials Engineering: Faculty Publications

Transdermal drug delivery systems have been successful for decades. Now these devices can be further scaled down, and their applications have been extended to wide selections of cargo, ranging from natural molecules (e.g., insulin and glucose) to bioengineered molecules (e.g., nanoparticles and vaccines). Some emerging nanopatches show promise for precise single-cell gene transfection in vivo and have advantages over conventional tools in terms of delivery efficiency, safety, and controllability of delivered dose. In this review, we discuss recent technical advances in wearable micro/nano devices with unique capabilities or potential for single-cell biosensing and transfection in the skin or other organs, …


Segregation Of Mo Atoms Into Stacking Faults In Crfeconimo Alloy, Kaisheng Ming, Xiaofang Bi, Jian Wang Jan 2019

Segregation Of Mo Atoms Into Stacking Faults In Crfeconimo Alloy, Kaisheng Ming, Xiaofang Bi, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

Solute segregation at dislocations can impede the motion of dislocations, strengthening materials. Here, we study the formation and role of solute segregation at dislocations in CrFeCoNiMo high-entropy alloys (HEAs) by high-angle annular dark-field scanning transmission electron microscopy imaging and mechanical testing both deformed and annealed samples. Mo atoms exhibit pronounced segregation into the planar-extended core of dislocations, i.e. stacking faults, causing the increase in the yield strength while the loss of the ductility. This work suggests that mechanical properties of HEAs can be tailored by alloying additional elements that are in favor of segregation into dislocations.


Optimization Of Protein-Protein Interaction Measurements For Drug Discovery Using Afm Force Spectroscopy, Yongliang Yang, Bixi Zeng, Zhiyong Sun, Amir Monemianesfahani, Jing Hou, Nian-Dong Jiao, Lianqing Liu, Liangliang Chen, Marc D. Basson, Lixin Dong, Ruiguo Yang, Ning Xi Jan 2019

Optimization Of Protein-Protein Interaction Measurements For Drug Discovery Using Afm Force Spectroscopy, Yongliang Yang, Bixi Zeng, Zhiyong Sun, Amir Monemianesfahani, Jing Hou, Nian-Dong Jiao, Lianqing Liu, Liangliang Chen, Marc D. Basson, Lixin Dong, Ruiguo Yang, Ning Xi

Department of Mechanical and Materials Engineering: Faculty Publications

Increasingly targeted in drug discovery, protein-protein interactions challenge current high throughput screening technologies in the pharmaceutical industry. Developing an effective and efficient method for screening small molecules or compounds is critical to accelerate the discovery of ligands for enzymes, receptors and other pharmaceutical targets. Here, we report developments of methods to increase the signal-to-noise ratio (SNR) for screening protein-protein interactions using atomic force microscopy (AFM) force spectroscopy. We have demonstrated the effectiveness of these developments on detecting the binding process between focal adhesion kinases (FAK) with protein kinase B (Akt1), which is a target for potential cancer drugs. These developments …


Local Control Robotic Surgical Devices And Related Methods, Eric Markvicka, Tom Frederick, Jack Mondry, Joe Bartels, Shane Michael Farritor Jan 2019

Local Control Robotic Surgical Devices And Related Methods, Eric Markvicka, Tom Frederick, Jack Mondry, Joe Bartels, Shane Michael Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

The various robotic medical devices include robotic devices that are disposed within a body cavity and positioned using a support component disposed through an orifice or opening in the body cavity. Additional embodiments relate to devices having arms coupled to a device body wherein the device has a minimal profile such that the device can be easily inserted through smaller incisions in comparison to other devices without such a small profile. Further embodiments relate to methods of operating the above devices.


Medical Inflation, Attachment And Delivery Devices And Related Methods, Mark Rentschler, Shane Michael Farritor Jan 2019

Medical Inflation, Attachment And Delivery Devices And Related Methods, Mark Rentschler, Shane Michael Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

The various embodiments disclosed herein relate to procedural space maintenance devices, medical device positioning devices, and devices that provide both procedural space maintenance and device positioning. Further embodiments relate to medical device insertion and/or retraction devices.


Test 2209a: New Holland Wormaster 70, Nebraska Tractor Test Lab Jan 2019

Test 2209a: New Holland Wormaster 70, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Validation Of The Highway Capacity Manual Urban Street Travel Time Reliability Methodology Using Empirical Data, Ernest Tufuor, Laurence Rilett Jan 2019

Validation Of The Highway Capacity Manual Urban Street Travel Time Reliability Methodology Using Empirical Data, Ernest Tufuor, Laurence Rilett

Mid-America Transportation Center: Final Reports and Technical Briefs

The 6th edition of the Highway Capacity Manual (HCM-6) includes the concept of travel time reliability (TTR), which attempts to determine the distribution of average trip travel times over an extended period. TTR is an inherent part of travelers’ route choice decisions and is used by traffic managers to better quantify operations rather than simply using average travel times. The focus of this paper is on the HCM-6 urban street TTR methodology contained in Chapter 17. The approach uses historical data (e.g., weather and volume fluctuations) and simple empirical data (e.g., 1-day volume count) to provide the user with average …


Mechanical Response Of He- Implanted Amorphous Sioc/ Crystalline Fe Nanolaminates, A. Zare, Q. Su, J. Gigax, T. A. Harriman, M. Nastasi, L. Shao, D. A. Lucca Jan 2019

Mechanical Response Of He- Implanted Amorphous Sioc/ Crystalline Fe Nanolaminates, A. Zare, Q. Su, J. Gigax, T. A. Harriman, M. Nastasi, L. Shao, D. A. Lucca

Nebraska Center for Energy Sciences Research: Publications

This study investigates the microstructural evolution and mechanical response of sputter-deposited amorphous silicon oxycarbide (SiOC)/crystalline Fe nanolaminates, a single layer SiOC film, and a single layer Fe film subjected to ion implantation at room temperature to obtain a maximum He concentration of 5 at. %. X-ray diffraction and transmission electron microscopy indicated no evidence of implantation-induced phase transformation or layer breakdown in the nanolaminates. Implantation resulted in the formation of He bubbles and an increase in the average size of the Fe grains in the individual Fe layers of the nanolaminates and the single layer Fe film, but the bubble …


Pawnee Dam Inflow Design Flood (Idf) Update And Stage-Frequency Curve Development Using Rmcrfa, Jennifer P. Christensen, Joshua J. Melliger Jan 2019

Pawnee Dam Inflow Design Flood (Idf) Update And Stage-Frequency Curve Development Using Rmcrfa, Jennifer P. Christensen, Joshua J. Melliger

United States Geological Survey: Water Reports and Publications

Pawnee Dam is one of the ten Salt Creek Dams designed and built in the 1960s to mitigate flooding in Lincoln, Nebraska. This short paper illustrates the update of the Pawnee Dam inflow design flood (IDF) through calibration to recent high flow events and the development of its stage-frequency or hydrologic loading curve with the U.S. Army Corps of Engineers’ Risk Management Center Reservoir Frequency Analysis (RMC-RFA) model. The IDF update follows Engineering Regulation 1110-8-2, Inflow Design Flood for Dams and Reservoirs, including unit hydrograph peaking and two antecedent pool elevations. Background information on the original design of the dam …


Test 2216: Kubota M7-172, Nebraska Tractor Test Lab Jan 2019

Test 2216: Kubota M7-172, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 2214: Kubota M7-132, Nebraska Tractor Test Lab Jan 2019

Test 2214: Kubota M7-132, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Effect Of Moisture Condition On Concrete Core Strengths, Wally Heyen, Lieska Halsey Jan 2019

Effect Of Moisture Condition On Concrete Core Strengths, Wally Heyen, Lieska Halsey

Nebraska Department of Transportation: Research Reports

The main purpose of this study was to determine if there would be any major differences between curing methods of cores taken for acceptance testing from a highway slab on a project. The comparison provided data to determine the effect of the moisture gradients created by these different curing treatments on core strength and core permeability. The strengths were measured of moist cured cores and sealed plastic bag cured cores from the day cores were obtained (14, 21 and 26 days) until they reached 28 days. Permeability was also measured at 26, 28 and 32 days. According to ASTM C42, …


Investigating The Interaction Of Ndot Hot-Pour Pcc Joint Sealant And Penetrating Concrete Sealers, Bruce Barrett, Dale Byre, Wally Heyen, Lieska Halsey, David Hansen Jan 2019

Investigating The Interaction Of Ndot Hot-Pour Pcc Joint Sealant And Penetrating Concrete Sealers, Bruce Barrett, Dale Byre, Wally Heyen, Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

Based on the field observations on NE-83, PCS potentially impacts the bond between the concrete and hot-pour sealant after application. If penetrating sealers break the interfacial bond after application, concrete pavements could become compromised and subject to freeze-thaw damage, chloride attack, and other deleterious effects.

The results show that discoloration occurred when applying the five PCS products to the NE-3405 hot-pour sealed testing blocks. All three test methods of application; spraying, 1-min, and 5-min soaks, caused discoloration. The level of discoloration increased with the duration of contact with the PCS. Despite discoloration, none of the five PCS products caused de-bonding …


Research On High-Rap Asphalt Mixtures With Rejuvenators - Phase Ii, Hamzeh Haghshenas, Gabriel Nsengiyumva, Yong-Rak Kim, Kommidi Santosh, Soroosh Amelian Jan 2019

Research On High-Rap Asphalt Mixtures With Rejuvenators - Phase Ii, Hamzeh Haghshenas, Gabriel Nsengiyumva, Yong-Rak Kim, Kommidi Santosh, Soroosh Amelian

Nebraska Department of Transportation: Research Reports

A previous study by the authors have demonstrated effectiveness of three rejuvenators: R1 (triglyceride/fatty acid: agriculture-tech based), R2 (aromatic extract: petroleum-tech based), and R3 (tall oil: green-tech based) on rejuvenating properties of the aged binder. In that study, it was observed that the rejuvenators made high-RAP mixtures softer and more compliant, which may increase the rutting potential, while they simultaneously improve cracking resistance of the high-RAP materials. Research outcomes and findings from the previous study resulted in consequential research needs for more specific investigation of high-RAP mixtures with rejuvenators in order to achieve realistic implementation into future high-RAP paving projects …


Validation Of The Mechanical Rocker Test Method For Ice Melting Capacity (Mrt-Imc), Lieska Halsey, David Hansen Jan 2019

Validation Of The Mechanical Rocker Test Method For Ice Melting Capacity (Mrt-Imc), Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

The anti-icing and deicing industry has interest in the development of an objective, repeatable test procedure for the evaluation and comparison of anti-icing and deicing products. Pursuant to this goal, the Nebraska Department of Transportation (NDOT) funded research at the University of Nebraska-Lincoln (UNL) to investigate methods for evaluating deicing products, beginning in 2011[1]. Researchers at UNL developed the procedure for the Mechanical Rocker Test for Ice Melting Capacity (MRT or MRT-IMC) in 2014[2].

From 2017-2019, NDOT evaluated the MRT-IMC procedure for validity and suitability as a standard test procedure for assessing deicer performance. NDOT also explored opportunities to improve …


Cpt-Based Pile Design, Chung R. Song, Seunghee Kim, Binyam Bekele, Jingtao Zhang, Alex Silvey Jan 2019

Cpt-Based Pile Design, Chung R. Song, Seunghee Kim, Binyam Bekele, Jingtao Zhang, Alex Silvey

Nebraska Department of Transportation: Research Reports

The geotechnical design of a pile foundation is concerned with the determination of the safe magnitude of an external load that the foundation can carry without jeopardizing the stability of the supported structure. In recent years, in-situ sounding tests are becoming a more attractive method to predict pile capacity due to the rapid development of testing instruments, improved understanding of their mechanics and interpretation, and cost efficiency. The cone penetration test (CPT) and its upgraded version, the piezocone penetration test (PCPT), are the most widely used in situ sounding tests to predict pile capacity. This research report compared eight CPT-based …


Need For Aeromedical Evacuation High-Level Containment Transport Guidelines, Shawn G. Gibbs, Jocelyn J. Herstein, Aurora B. Le, Elizabeth L. Beam, Theodore J. Cieslak, James V. Lawler, Joshua L. Santarpia, Terry L. Stentz, Kelli R. Kopocis-Herstein, Chandran Achutan, Gary W. Carter, John J. Lowe Jan 2019

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

Durham School of Architectural Engineering and Construction: Faculty Publications

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


Hvac System Remote Monitoring And Diagnosis, Jeffrey N. Arensmeier, Gregg M. Hemmelgarn, Fadi M. Alsaleem, Priotomo Abiprojo Jan 2019

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

Durham School of Architectural Engineering and Construction: Faculty Publications

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


Strategies And Resources For Government Agencies To Utilize Disadvantaged Business Enterprises In Transportation Design-Build Projects, Baabak Ashuri, Adjo Amekudzi-Kennedy, Stephanie Amoaning-Yankson, Yunping Liang, Yang Cao Jan 2019

Strategies And Resources For Government Agencies To Utilize Disadvantaged Business Enterprises In Transportation Design-Build Projects, Baabak Ashuri, Adjo Amekudzi-Kennedy, Stephanie Amoaning-Yankson, Yunping Liang, Yang Cao

Durham School of Architectural Engineering and Construction: Faculty Publications

The Disadvantaged Business Enterprise (DBE) Program was established to provide opportunities for businesses owned and controlled by socially and economically disadvantaged individuals, such as minority-owned and women-owned businesses, to participate in federally funded transportation-related projects. Such DBE participation has increasingly been achieved over the years with the appropriate guidance for traditional project delivery: design-bid-build. However, in recent times the onset of alternative project delivery methods, such as design-build (DB), has introduced challenges for state DOTs trying to implement the DBE program using traditional approaches. This paper presents a synthesis of strategies and resources being used in state DOTs to achieve …


Effects Of Correlation Of Channel Gains On The Secrecy Capacity In The Gaussian Wiretap Channel, Abhishek Lokur Jan 2019

Effects Of Correlation Of Channel Gains On The Secrecy Capacity In The Gaussian Wiretap Channel, Abhishek Lokur

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Secrecy capacity is one of the most important characteristic of a wireless communication channel. Therefore, the study of this characteristic wherein the system has correlated channel gains and study them for different line-of-sight (LOS) propagation scenarios is of ultimate importance.

The primary objective of this thesis from the mathematical side is to determine the secrecy capacity (SC) for correlated channel gains for the main and eavesdropper channels in a Gaussian Wiretap channel as a function from main parameters (μ, Σ, ρ). f(h1, h2) is the joint distribution of the two channel gains at channel use (h …


Actual Evapotranspiration And Crop Coefficients Of Irrigated Lowland Rice (Oryza Sativa L.) Under Semiarid Climate, Koffi Djaman, Daran R. Rudnick, Yonnelle D. Moukoumbi, Abdoulaye Sow, Suat Irmak Jan 2019

Actual Evapotranspiration And Crop Coefficients Of Irrigated Lowland Rice (Oryza Sativa L.) Under Semiarid Climate, Koffi Djaman, Daran R. Rudnick, Yonnelle D. Moukoumbi, Abdoulaye Sow, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Lowland irrigated rice is the predominant crop produced in the Senegal River Valley characterized by very low annual rainfall, high temperatures, and low relative humidity. The Senegal River is shared by Senegal, Mali, Mauritania, and Guinea, and serves as the main source of irrigation water for the adopted double rice cropping system. Developing appropriate resource management strategies might be the key factor for the sustainability of rice production in the region. This study aims to estimate rice seasonal evapotranspiration (ETa), irrigation water requirement, and to develop rice growth stage specific crop coefficients (Kc) to improve rice water productivity. Field experiments …


Metabolic Compounds Within The Porcine Uterine Environment Are Unique To The Type Of Conceptus Present During The Early Stages Of Blastocyst Elongation, Sophie C. Walsh, Jeremy R. Miles, Linxing Yao, Corey D. Broeckling, Lea A. Rempel, Elane C. Wright-Johnson, Angela K. Pannier Jan 2019

Metabolic Compounds Within The Porcine Uterine Environment Are Unique To The Type Of Conceptus Present During The Early Stages Of Blastocyst Elongation, Sophie C. Walsh, Jeremy R. Miles, Linxing Yao, Corey D. Broeckling, Lea A. Rempel, Elane C. Wright-Johnson, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The objective of this study was to identify metabolites within the porcine uterine milieu during the early stages of blastocyst elongation. At Days 9, 10, or 11 of gestation, reproductive tracts of White cross‐bred gilts (n = 38) were collected immediately following harvest and flushed with Roswell Park Memorial Institute‐1640 medium. Conceptus morphologies were assessed from each pregnancy and corresponding uterine flushings were assigned to one of five treatment groups based on these morphologies: (a) uniform spherical (n = 8); (b) heterogeneous spherical and ovoid (n = 8); (c) uniform ovoid (n = 8); (d) heterogeneous …


Skip This Chore: Cleaning Your Air Conditioner Condenser Probably Won't Make It Work Better, David Yuill Jan 2019

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

Durham School of Architectural Engineering and Construction: Faculty Publications

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

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


Heat Pump And Air Conditioning Grading Systems And Methods, Fadi Mohammad Alsaleem Jan 2019

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

Durham School of Architectural Engineering and Construction: Faculty Publications

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


Building Envelope And Interior Grading Systems And Methods, Fadi Mohammad Alsaleem Jan 2019

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

Durham School of Architectural Engineering and Construction: Faculty Publications

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


Nebraska Summary: S1178 Fendt 933, Nebraska Tractor Test Lab Jan 2019

Nebraska Summary: S1178 Fendt 933, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


The Impact Of Extreme Virtual Elevation Above Grade On Construction Workers' Physiological Responses, Physical Responses, And Task Performance, Mahmoud Habibnezhad Jan 2019

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 …


Post-Earthquake Assessment And Numerical Modeling Of Freestanding Heritage Structures, M. Khalid Saifullah, Christine E. Wittich Jan 2019

Post-Earthquake Assessment And Numerical Modeling Of Freestanding Heritage Structures, M. Khalid Saifullah, Christine E. Wittich

Department of Civil and Environmental Engineering: Faculty Publications

Historic and heritage structures are particularly vulnerable to earthquakes, where damage or collapse can not only lead to loss of a structure but also the loss of irreplaceable heritage. Many heritage structures can be classified as freestanding (detached) structures, including unreinforced masonry walls, classical multi-drum columns, and statue-pedestal systems. However, the seismic response of freestanding structures (sliding, rocking, rock-slide, overturning) is poorly predicted by existing methods due to geometric non-linearities as well as sensitivity to interface conditions and modeling parameters. Previous studies have focused on analytical modeling of simplified systems and/or experimentation under controlled laboratory conditions. In contrast, this paper …


Post-Fire Damage Geospatial Assessment Via Point Clouds Of A Highway Bridge Structure, Yijun Liao, M Ebrahim Mohammadi, Richard L. Wood, Christine E. Wittich Jan 2019

Post-Fire Damage Geospatial Assessment Via Point Clouds Of A Highway Bridge Structure, Yijun Liao, M Ebrahim Mohammadi, Richard L. Wood, Christine E. Wittich

Department of Civil and Environmental Engineering: Faculty Publications

This paper discusses the quantitative post-fire damage assessment of a steel girder bridge via point clouds. In this case study, the point cloud was collected using light detection and ranging (lidar) for a detailed geometric and shape analysis. The out-of-plane deformation was analyzed to locate and quantify buckling across the length of the steel girders.