Engineering Commons^™

Head Impact Effects In Small Remotely Piloted Aircraft System (Srpas) Collisions: Gender Specific Risks And Vulnerable Population Protection, Md Farhan Hoque Sagar

Electronic Thesis and Dissertation Repository

This study focuses on supporting the development of safety regulations for vulnerable populations during drone to head impacts. First, the small female head and neck model was compared to cadaveric data. Then, combined with lab’s previous work, gender-based disparities in head impact responses were highlighted, with small females experiencing higher injury risk metrics, despite lower skull von Mises stress. Beyond small females, children of various ages and their head responses during impacts were also analyzed. In addition to the previously developed quadcopter drone model, a new Mavic Pro drone model was developed, and this model was integrated with human head …

Parametric Analysis And Enhancement Of The Burst Capacity Model For Composite-Repaired Corroded Pipelines, Rodrigo Silva Silva-Santisteban

Electronic Thesis and Dissertation Repository

One of the main causes of pipeline failures is corrosion, which leads to a localized loss of the pipe wall thickness and hence compromises the capacity of the pipeline. Composite repair is a method to rehabilitate corroded pipelines. Design codes such as ASME PCC-2 are commonly used to design the repair thickness. As the predictive accuracy to determine the burst capacity of a composite repaired pipeline with existing models is generally poor, the main objective of the present thesis is to provide insights on the parameters that affect the burst capacity and propose improvements to the prediction of burst capacity …

Guidelines For Designing The Overhead Transmission Tower Foundations Adjacent To Cohesionless Slopes, Meshel Q. Alkahtani

Electronic Thesis and Dissertation Repository

Foundations supporting electrical transmission line towers are subjected to oblique loading due to tower own weight along with wind loading. Due to land limitation and linear alignment of transmission lines, many power transmission towers are situated in sand near sloping grounds and proper evaluation of their foundation performance is essential for the safety and reliability of the critical power transmission lines. There is currently no guidance available on the behaviour of transmission towers foundations constructed near slopes. Thus, the primary objectives of this study are to evaluate the response of transmission tower foundations in cohesionless sloping grounds and investigate the …

Investigation Of Small Remotely Piloted Aircraft System (Srpas) To Human Head Impact, Yuhu Weng

Electronic Thesis and Dissertation Repository

Small remotely piloted aircraft system (sRPAS) to ground human head impact could cause injuries to the public. Skull fractures and brain injuries have been observed in sRPAS-related impacts, which varied in angles, locations and velocities. This study developed a representative quadcopter sRPAS finite element model and incorporated it with THUMS ver 4.02 50^th percentile male and 5^th percentile small female models to simulate sRPAS to human head impacts. The simulations were validated with cadaver experiments. The common injury metrics such as head injury criteria (HIC) and brain injury criterion (BrIC) were correlated with head injury-related responses such as …

Developing Multi-Species Brain-Strain-Based Scaling Law Using Finite Element Analysis., Xingyu Liu

Electronic Thesis and Dissertation Repository

To better understand traumatic brain injury (TBI), various laboratory animal experiments have been developed. However, there lacks an effective scaling to connect animal TBI models with human brain injuries. With the help of the finite element (FE) model, brain mechanical responses such as strains can be predicted, and hence can serve as a parameter to facilitate animal to human scaling, as these tissue-level strains directly link to neuronal damage. In this thesis, first, a comprehensive comparison of brain strains between animal TBI models and human TBI cases was conducted. Then, a brain-strain-based scaling law between mouse and human was developed, …

Biomechanical Analysis Of Commotio Cordis In Children's Baseball - A Computational Approach, Grant J. Dickey

Electronic Thesis and Dissertation Repository

Commotio cordis is the second leading cause of cardiac death in young athletes. This rare sudden-death mechanism most commonly affects young children playing baseball. It is caused by impacts to the chest during the repolarization phase of the cardiac cycle, which causes the heart to go into ventricular fibrillation, often leading to death. This study adopted the detailed and validated CHARM-10 child finite element model to replicate commotio cordis instances by simulating baseball impacts to the chest. New commotio cordis injury metrics were developed to create a more accurate prediction for chest protector effectiveness. The conventionally used injury metrics for …

Finite Element Analysis Of Buckling Capacity Of Conical Steel Tanks Considering Field-Measured Initiation Imperfections – A Case Study, Haoyi Zhang

Electronic Thesis and Dissertation Repository

The geometric imperfection in elevated steel conical water tanks is a key factor that influences the buckling capacity of the tank. Current considerations of imperfections in the design of conical tanks are based on theoretical analysis, whereby the imperfection shapes and locations are assumed to have the most critical impact on the capacity. This thesis investigates the initial imperfections of an actual stiffened liquid-filled steel conical tank (LFCT) based on high-resolution laser scan measurement data of the tank geometry.

In the first part of this study, detailed analyses of the laser scan data were carried out to extract the global …

Finite Element Analyses And Random Field Modeling Of Naturally Corroded Underground Energy Pipelines, Ji Bao

Electronic Thesis and Dissertation Repository

Metal-loss corrosion is one of the major threats to the integrity of oil and natural gas pipelines. The Fitness-For-Service (FFS) assessment is commonly carried out to demonstrate the integrity of the corroded pipelines. The naturally occurring corrosions on the external surfaces are irregularly shaped three-dimensional features. Due to the geometric complexity of the natural corrosion features, the research of FFS assessment in the previous studies always employed the pipe segments containing artificially induced corrosion features. However, since artificial features are in general regular-shaped, e.g. cubic or semi-ellipsoidal, they do not capture geometric characteristics of naturally occurring corrosions. The thesis develops …

Ultimate And Serviceability Limit States Of Large Shallow Foundations Under Combined Loading, Pengpeng He

Electronic Thesis and Dissertation Repository

Estimation of the bearing capacity and deformations of large shallow foundations under combined loadings can be of great significance. Some geotechnical design guidelines recommend the failure load envelope method for ultimate limit state analysis. Since many investigations of this method focus primarily on undrained failure envelopes using unlimited-tension interfaces, zero-tension interfaces have not been well investigated. In addition, less work is available on drained failure envelopes. For serviceability limit states, the majority of approaches used are based on uncoupled, isotropic assumptions. Further work needs to be done on more appropriate elastic solutions for combined loadings.

General VHMT failure envelopes for …

Computational Modeling Of The Human Brain For Mtbi Prediction And Diagnosis, Yanir Levy

Electronic Thesis and Dissertation Repository

Sports related concussions and mild traumatic brain injuries have seen an increase in frequency over the past decade. The creation of highly biofidelic computational head models is an important step in understanding the mechanisms of these mild brain injuries and preventing them. Hence, the purpose of this research is to combine state-of-the-art computational models, brain imaging modalities and traditional head injury assessment protocols to simulate and predict the brains responses during traumatic head impacts. A novel, atlas-based, parcellated axon fiber embedded head model was developed which allows for in-depth analysis of the brain’s structural connectome tracts for injury diagnosis and …

A Computational Investigation Into Acromial Fractures After Reverse Total Shoulder Arthroplasty, Jason Lockhart

Electronic Thesis and Dissertation Repository

Acromial fractures are a debilitating complication following reverse total shoulder arthroplasty (RTSA). The purpose of this work is to (1) improve the current state of FE bone stress estimates after RTSA and to investigate the effects of (2) plane of elevation, (3) hand loads, and (4) baseplate screw position on scapular spine stress. The FE method used was validated against an in-vitro strain gauge based experiment and found to be accurate in the prediction of stress increases and decreases after RTSA. The coronal plane of elevation was found to increase scapular spine stress compared to more central planes of elevation. …

Analysis Of Roofs Of Wooden Houses Under Uplift Wind Loads- Analytical Solution, Retrofit, And Reliability Analysis, Adnan Farouk Enajar

Electronic Thesis and Dissertation Repository

Observations of post-hurricane events indicate that light-frame wood houses are vulnerable to failure

Observations of post-hurricane events indicate that light-frame wood houses are vulnerable to failure due to the inability of their connections to provide sufficient transfer of uplift wind loads from the roof of the house to the foundation. One of these connections is the roof-to-wall connection (RTWC), which connects roof trusses to the top plate members of the walls. This issue has been investigated through full-scale testing at the Insurance Research Lab for Better Homes. This thesis describes the detailed finite element modelling performed for this full-scale testing …

Finite Element Analysis Of Hollow-Stemmed Shoulder Implants In Different Bone Qualities Derived From A Statistical Shape And Density Model, Pendar Soltanmohammadi

Electronic Thesis and Dissertation Repository

The incidence of total shoulder arthroplasty procedures (TSA) to treat osteoarthritis has experienced the most rapid growth among all human joint replacements. However, stress shielding of proximal bone following its reconstruction is a complication of TSA triggering unfavorable adaptive bone remodeling, especially for osteoporotic patients.

A better understanding of how the shape and density of the shoulder vary among members of a population can help design more effective population-based orthopedic implants. Therefore, finite element models representing healthy, osteopenic, and osteoporotic bone qualities in a population were developed using our statistical shape and density model. Bones were reconstructed with hollow- and …

Investigation Of Ductile Crack Growth And Normalization Method For Se(T) Specimen Using Finite Element Analyses, Cheng Qian

Electronic Thesis and Dissertation Repository

The fracture toughness resistance curve (e.g. J-R curve) is widely used in integrity assessment and strain-based design of oil and gas pipelines with respect to planar defects (i.e. cracks). This thesis includes two-dimensional (2D) and three-dimensional (3D) finite element analyses (FEA) of ductile crack growth of X80-grade pipeline steel based on the Gurson-Tvergaard-Needleman (GTN) constitutive model, and investigation of the normalization (NM) method to generate the J-R curve for the single-edge tension (SE(T)) specimen.

First, the GTN model implemented in the computational cell is adopted in the commercial software ABAQUS to calibrate the micromechanical parameters for the pipeline steel. Subsequently, …

Osteoarthritis Induced Glenoid Morphology And Bone Quality: An Evaluation Of Augmented Glenoid Components, Nikolas K. Knowles

Electronic Thesis and Dissertation Repository

Osteoarthritis of the glenoid results in regional bone density variations and bone loss that may compromise early component fixation and support. The two common morphologies, symmetric and asymmetric erosion, were characterized by bone density and morphology, and assessed on the basis of bone removal and bone quality in the context of augmented glenoid components. The bone strain field was also compared when different augmented glenoid components underwent simulated joint loading using finite element analysis.

Asymmetrically eroded glenoids were found to have denser bone (p

On The Application Of Mechanical Vibration In Robotics-Assisted Soft Tissue Intervention, Iman Khalaji

Electronic Thesis and Dissertation Repository

Mechanical vibration as a way of transmitting energy has been an interesting subject to study. While cyclic oscillation is usually associated with fatigue effect, and hence a detrimental factor in failure of structures and machineries, by controlled transmission of vibration, energy can be transferred from the source to the target. In this thesis, the application of such mechanical vibration in a few surgical procedures is demonstrated.

Three challenges associated with lung cancer diagnosis and treatment are chosen for this purpose, namely, Motion Compensation, tumor targeting in lung Needle Insertion and Soft Tissue Dissection:

1. A robotic solution is proposed …

Performance Of Hollow Bar Micropiles Under Axial And Lateral Loads In Cohesive Soils, Ahmed Yehia Abd El-Aziz

Electronic Thesis and Dissertation Repository

The use of hollow core bars in micropiles has greatly increased over the past ten years. Hollow core construction, also known as “self drilled”, is becoming a popular option because it allows a faster installation processes and ground improvement at the same time. Despite the growing demand for hollow bar micropiles, little work has been devoted to evaluating the nominal bond strength between the micropile grout and the surrounding soil, especially in clayey soils. Moreover, the performance of such micropiles under different kinds of loading is still largely unknown and needs to be investigated.

In this study, a research methodology …

Thermal And Mechanical Studies Of Thin Spray-On Liner (Tsl) For Concrete Tunnel Linings, Taesang Ahn

Electronic Thesis and Dissertation Repository

The thesis presents a summary of Thin Spray-On Liner (TSL) effects on concrete. Three aspects, fire insulation, adhesion strength on concrete surface and load carrying capacity (i.e. flexural strength) on segmental concrete liners, are presented. Small-scale to full-scale laboratory tests were conducted using ASTM standards or devised methods. The TSL effects on three aspects were then compared with the results for uncoated concrete specimens. Numerical analyses using TEMP/W for the thermal response of TSL and a FE program, ABAQUS for the mechanical response of TSL were respectively carried out and compared with the measured results. Additionally, numerical analyses in respect …