Seismic Performance of Steel Pipe Pile to Cap Beam Moment Resisting Connections

INE/AUTC 13.0

Imaging of a fluid injection process using geophysical data - A didactic example

In many subsurface industrial applications, fluids are injected into or withdrawn from a geologic formation. It is of practical interest to quantify precisely where, when, and by how much the injected fluid alters the state of the subsurface. Routine geophysical monitoring of such processes attempts to image the way that geophysical properties, such as seismic velocities or electrical conductivity, change through time and space and to then make qualitative inferences as to where the injected fluid has migrated. The more rigorous formulation of the time-lapse geophysical inverse problem forecasts how the subsurface evolves during the course of a fluid-injection application. Using time-lapse geophysical signals as the data to be matched, the model unknowns to be estimated are the multiphysics forward-modeling parameters controlling the fluid-injection process. Properly reproducing the geophysical signature of the flow process, subsequent simulations can predict the fluid migration and alteration in the subsurface. The dynamic nature of fluid-injection processes renders imaging problems more complex than conventional geophysical imaging for static targets. This work intents to clarify the related hydrogeophysical parameter estimation concepts

Comparison of Acute Cardiometabolic Responses in a 7-Minute Body Weight Circuit to 7-Minute HIIT Training Protocol

International Journal of Exercise Science 13(2): 395-409, 2020. To investigate the acute cardiometabolic responses of a 7-minute bodyweight resistance exercise circuit (HICE) compared to a 7-minute high intensity interval training cycle protocol (HIIE). Methods: Twelve apparently healthy and active young adults were enrolled in a randomized crossover study (HICE vsHIIE). The 12 HICE exercises used a 30:5 second exercise to rest ratio, followed by a 3-minute cool-down and was replicated in the HIIE cycle protocol. Following each protocol, subjects were seated for the next hour. Measurements included blood pressure (BP) heart rate, blood glucose and triglycerides, taken prior to exercise, immediately after, 15, 30, 45, and 60-minutes post-exercise. Blood glucose and triglycerides were only taken, immediately after and at 60-minutes. General mixed linear modeling was used to analyze the data and Cohen’s dwas calculated for effect size. Post hocanalysis of individual time points used Bonferroni adjustment. Results: There was no significant difference in overall systolic BP between HIIE and HICE (p = 0.168). However, there was a significant difference in overall diastolic BP resulting a higher response in HIIE (p = 0.002). Immediately after exercise exhibited significant (p = 0.001) and trending, respectfully, higher values in diastolic BP for HIIE. The overall post-exercise heart rate was lower for HIIE vsHICE (p \u3c 0.001). Blood glucose and Triglycerides had no overall difference between the two protocols (p = 0.104). Conclusion: The HICE protocol had a similar cardiometabolic response post-exercise to HIIE but did have a reduction in diastolic BP post-exercise. However, post-exercise heart rate was higher

Blood Lactate Response to Active Recovery in Athletes vs. Non-Athletes

Previous research has indicated an optimal intensity for active recovery following a bout of exercise for the removal of blood lactate to be at 80% of the individual’s lactate threshold. However, these previous research studies have relied primarily on highly trained athletes. Therefore, the 80% of lactate threshold might not be the optimal intensity for non-athlete populations attempting to recover from lactate producing exercise. Purpose: To investigate the acute blood lactate response during active recovery at 80% of lactate threshold for athletes vs. non-athletes following a vigorous bout of activity. Methods: Apparently healthy and active young adults (N=16, 56% male, 21±1 yr, BMI: 26.5±3.6 kg/m2, SBP: 122±13 mmHg, DBP: 71±8 mmHg) were enrolled in a cohort study design that separates subjects into highly trained collegiate athletes (participating in a NCAA sport) and non-athletes. Each subject had two study visits. Visit one included collection of subject characteristics including baseline values of blood pressure and heart rate via an automated device, and blood lactate via finger stick. Additionally, subjects underwent a Bruce Protocol on a treadmill to determine lactate threshold as well as VO2max. Visit two consisted of a treadmill warm up at 5 mph and 0% incline followed by a brief running protocol at 90% of their VO2max for 5 minutes. Immediately following the 5 minutes, subjects engaged in active recovery at 80% of the subject’s lactate threshold until baseline lactate levels were reached or until 32 minutes of active recovery was completed. Measurements of heart rate and blood lactate were taken at rest, post-warm up, post-exercise bout, and every four minutes during active recovery for day two. Area under the curve (AUC) was calculated for blood lactate and general mixed linear modeling was used to compare AUC for athletes vs. non-athletes while Cohen’s d was calculated to determine effect size. Post hoc analysis of individual time points used Bonferroni adjustment. Alpha level was set at p\u3c0.05. Results: There was a significant difference in overall lactate (b= -109.8 mmol/L, p\u3c0.001, d= 2.32) as well as at each time point during the active recovery (all p\u3c0.005). There was also a significant difference in overall heart rate in favor of athletes having lower heart rate response throughout (b= -14 bpm, p=0.003, d= 0.164). When individual time points were analyzed, there was a significant difference in heart rate at time point 7 (b=-20 bpm, p\u3c0.005, d= 2.243), time point 8 (b=-21 bpm, p\u3c0.005, d= 2.305), and at time point 10 (b=-18.533 bpm, p\u3c0.005, d= 2.080) in favor of lower heart rate for athletes. Conclusion: Active Recovery at 80% of lactate threshold demonstrated a significant difference in the removal of lactate for athletes compared to non-athletes. Future research should investigate the most efficient workload for the removal of blood lactate in non-athletes, potentially an intensity that lowers non-athletes heart rates more than the intensity used in this study

The Effects of Music on Muscle Fatigue and Strength in Individuals with Previous Knee Injuries

Music can be used during physical activity for a variety of ergogenic, psychological, and psychophysical benefits. Listening to one’s preferred genre of music has been found to optimize arousal and increase motivation during an exercise bout that can lead to performance improvements. Rehabilitation patients often struggle to adhere to their rehabilitation for a variety of reasons, including lack of enjoyment, lack of progress, or even increased pain or fatigue. Therefore, incorporating music into a rehabilitation setting could help patients improve their strength and reduce fatigue, thus improving rehabilitation adherence. PURPOSE: To examine the effects of music preference on muscle fatigue and strength in individuals who suffered a previous knee injury. METHODS: Males (n = 14) and females (n = 10) between the ages of 18 and 55 (M = 23.21, SD = 6.77) who previously had an ACL, meniscus, PCL, MCL, or LCL injury (with or without surgical intervention) between one but no more than 13 years ago participated in this study. A randomized crossover design was used with each participant completing three days of testing (no music, preferred music, and non-preferred music as determined via a questionnaire at initial visit) with each session occurring at least 48 hours apart. During every session, participants first warmed up on a cycle ergometer at 50 watts for five minutes before undergoing a Thortensson fatigue test via the Biodex dynamometer. Measures of quadriceps strength and quadriceps fatigue were collected. During the two music conditions, music was played via a speaker throughout both the warm-up and Thortensson fatigue test. RESULTS: One-way repeated measures ANOVAs were conducted to assess for differences in quadriceps fatigue and strength across all three conditions. No significant differences were found across conditions in quadriceps fatigue (F(2,46) = 0.682, p = 0.510, ηp2 = 0.029) or quadriceps strength (F(2,46) = 1.447, p = 0.246, ηp2 = 0.059). CONCLUSION: There was no difference in muscular fatigue or strength between the three conditions. Therefore, listening to one’s preferred music may not improve strength or reduce fatigue in a rehabilitation setting. Rehabilitation practitioners should consider that music may not be the most effective strategy to increase muscular strength or reduce fatigue in a rehabilitation setting and should explore other techniques that could help address these variables and improve rehabilitation adherence

A Comparison of Resistance Exercise to Aerobic Exercise on Cognitive Processing Speed in Young Adults

Processing speed is the progression by which an individual receives information, begins to understand it, and then responds to it. Processing speed affects academic performance and research has established a positive relationship between exercise and processing speed. While the majority of research on cognition has focused on aerobic exercise, several studies have still demonstrated resistance exercise can improve cognitive abilities, including processing speed. However, these studies have relied primarily on a more tradition approach with free weights and machines. Additionally, there are a lack of studies directly comparing these modes of exercise (aerobic vs. resistance) and the appropriate duration of exercise to improve processing speed is not fully understood. PURPOSE: To explore if an acute 10-minute bout of resistance exercise, using body weight and resistance bands, compares to aerobic exercise on cognitive processing speed in young adults. METHODS: Healthy young adults (N = 29; male = 15, female = 14) underwent a repeated measures design with one control and two experimental conditions (aerobic, resistance). Visits took place at least 48 hours, but no more than 72 hours apart. During the control visit, participants completed the Symbol Search Subtest from the Wechsler Adult Intelligence Scale (WAIS-IV) via Inquisit computer software, a validated measure of processing speed. During the two experimental conditions, participants completed a 10-minute bout of moderate intensity aerobic or resistance exercise, determined by heart rate reserve response (40-59% of HRR). Following the brief exercise bout, the Symbol Search subtest was administered 11 minutes post-activity during the optimal window of assessment, as previously determined. RESULTS: A one-way repeated measures ANOVA was conducted to assess differences in processing speed across the conditions (control, aerobic, and resistance). The results revealed an overall significant effect (F(2,56) = 28.18, p \u3c 0.001, ηp2= 0.502) between the three conditions. Follow-up pairwise comparisons revealed participants performed better on processing speed following aerobic exercise compared to the control condition (p \u3c 0.001), and performed better following resistance exercise compared to the control condition (p \u3c 0.001). However, no statistically significant difference was found on processing speed between the aerobic exercise and resistance exercise conditions (p = 0.300). CONCLUSION: Our study compared a brief bout of aerobic and resistance exercise and determined that both resistance and aerobic exercise produced improvements in processing speed compared to the control condition, but no difference was found between the two exercise conditions. This suggests that a brief 10-minute bout of moderate intensity aerobic or resistance exercise can be utilized to improve processing speed in healthy college-aged students. Given the large number (40-50%) of college students in the U.S. who are inactive and report time as a barrier to exercise, either 10-minute bout of exercise used in the current study may be feasible for healthy young adults to engage in prior to performing tasks in which processing speed is essential, for example, timed examinations

The Effects of Load History and Design Variables on Performance Limit States of Circular Bridge Columns

This report discusses a research program aimed at defining accurate limit state displacements which relate to specific levels of damage in reinforced concrete bridge columns subjected to seismic hazards. Bridge columns are designed as ductile elements which form plastic hinges to dissipate energy in a seismic event. To satisfy the aims of performance based design, levels of damage which interrupt the serviceability of the structure or require more invasive repair techniques must be related to engineering criteria. For reinforced concrete flexural members such as bridge columns, concrete compressive and steel tensile strain limits are very good indicators of damage. Serviceability limit states such as concrete cover crushing or residual crack widths exceeding 1mm may occur during smaller, more frequent earthquakes. While the serviceability limit states do not pose a safety concern, the hinge regions must be repaired to prevent corrosion of internal reinforcing steel. At higher ductility demands produced by larger less frequent earthquakes, reinforcing bar buckling may lead to permanent elongation in the transverse steel, which diminishes its effectiveness in confining the concrete core. Bar buckling and significant damage to the core concrete represent the damage control limit states, which when exceeded lead to significant repair costs. Furthermore, rupture of previously buckled bars during subsequent cycles of loading leads to rapid strength loss. The life safety or collapse prevention limit state is characterized by fracture of previously buckled bars. The goal of the experimental program is to investigate the impact of load history and other design variables on the relationship between strain and displacement, performance strain limits, and the spread of plasticity. The main variables for the thirty circular bridge column tests included: lateral displacement history, axial load, longitudinal steel content, aspect ratio, and transverse steel detailing. A key feature of the experiments is the high fidelity strain data obtained through the use of an optical 3D position measurement system.Column curvature distributions and fixed-end rotations attributable to strain penetration of reinforcement into the footing were quantified. The following sequence of damage was observed in all of the cyclically loaded experiments: concrete cracking, longitudinal steel yielding, cover concrete crushing, confinement steel yielding, longitudinal bar buckling, and fracture of previously buckled reinforcement. The first significant loss in strength occurred when previously buckled reinforcement fractured. The measured data was used to refine strain limit recommendations. Particular attention was paid to the limit state of longitudinal bar buckling, since it limited the deformation capacity of all of the cyclically loaded specimens. Empirical expression were developed to predict the compressive strain at cover crushing, the compressive strain at spiral yielding, and the peak tensile strain prior to visible buckling after reversal of loading. In design, limit state curvatures are converted to target displacements using an equivalent curvature distribution. The Modified Plastic Hinge Method was developed to improve the accuracy of strain-displacement predictions. Key aspects of the proposed model which differentiate it from the current method include: (1) a decoupling of column flexure and strain penetration deformation components, (2) a linear plastic curvature distribution which emulates the measured curvature profiles, and (3) separate plastic hinge lengths for tensile and compressive strain-displacement predictions. In the experiments, the measured extent of plasticity was found to increase due to the combined effects of moment gradient and tension shift. The proposed tension hinge length was calibrated to match the upper bound of the measured spread of palsticity. The proposed compressive hinge length only contains a term related to the moment gradient effect. Expressions which describe the additional column deformation due to strain penetration of reinforcement into the adjoining member were developed. When compared to the current technique, the Modified Plastic Hinge Method improved the accuracy of both tensile and compressive strain-displacement predictions. Abstract for Volume 3: This report presents the numerical portion of the research project on the impacts of loading history on the behavior of reinforced concrete bridge columns. In well-detailed reinforced concrete structures, reinforcing bar buckling and subsequent bar rupture serve as common failure mechanisms under extreme seismic events. Engineers often use a strain limit state which is associated with bar buckling as the ultimate limit state, but the relationship between the strain demand and resultant bar buckling is not well understood. Past research has indicated large impact of the cyclic loading history on the strain demand to achieve reinforcing bar buckling. On the other hand, sectional analysis is widely implemented by engineers to relate strain to displacement. However, the cyclic load history also has potential impact on the relationship between strain limits and displacement limits. As a result, it is important to study the seismic load history effect on the strain limit state of reinforcing bar buckling and on the relationship between local strain and structural displacement. In addition, Performance-Based Earthquake Engineering (PBEE) strongly depends on an accurate strain limit definition, so a design methodology needs to be developed to identify the strain limit for reinforcing bar buckling including the seismic load history effect. Two independent finite element methods were utilized to accomplish the goal of this research work. First, fiber-based analysis was utilized which employed the Open System for Earthquake Engineering Simulation (OpenSees). The fiber-based method was selected because of its accuracy in predicting strains and its computational efficiency in performing nonlinear time history analysis (NTHA). The uniaxial material models in fiber-based sections were calibrated with data from material tests. In addition, strain data and force-deformation response from large scale testing assists selection of element types and integration schemes to ensure accuracy. The advanced beam-column elements and material models in OpenSees resulted in a very accurate prediction of strain at local sections as well as global dynamic response of structures. A number of nonlinear time history analyses with 40 earthquake ground motions were conducted to investigate the effect of seismic load history on relationship between structural displacement and strain of extreme fiber bars at the critical section. The second finite element model was established with solid elements to predict bar buckling. The model included a segment of reinforcing bar and its surrounding elements, such as spiral turns and concrete. This model separates itself from previous bar buckling research by utilizing actual sectional detailing boundary conditions and plastic material models instead of the simplified bar-spring model. The strain history is considered as the demand on this model. A series of strain histories from the experimental tests and fiber-based analyses were applied to the finite element model to study their impacts on the strain limit for reinforcing bar buckling. Initial analytical investigations have shown significant impact of load history on the strain demand to lead to reinforcing bar buckling in the plastic hinge region. This is also confirmed in the experimental observation which only included a limited number of load histories. The parametric study extended the range of load history types and also studied the effect of reinforcement detailing on bar buckling. On the other hand, analyses with fiber-based models showed that the load history rarely impacts the relationship between local strain and structural displacement. A design approach was developed to include the load history effect on the strain limit state of bar buckling.Volume I: LIST OF TABLES __________________________________________________ xv LIST OF SELECTED NOTATIONS _________________________________ xxxii Chapter 1: Introduction _______________________________________________ 1 1.1 Background – Performance Limit States ______________________ 1 1.2 The Need for Research ___________________________________ 3 1.3 Research Goals and Scope _________________________________ 5 Chapter 2: Test Setup, Instrumentation, Construction, and Text Matrix ______ 6 2.1 Test Setup _____________________________________________ 6 2.2 Test Matrix ____________________________________________ 13 2.3 Instrumentation ________________________________________ 16 2.4 Construction Process ____________________________________ 22 2.4.1 Construction Sequence ______________________________________ 23 2.4.2 Optotrak Target Marker Application Method _____________________ 39 Chapter 3: Experimental Observations _________________________________ 41 3.1 Contents of Report Volume 2 _____________________________ 41 Chapter 4: The Effect of Load History on Column Performance ____________ 43 4.1 Introduction ___________________________________________ 43 4.1.1 Test Setup ________________________________________________ 46 4.1.2 Instrumentation ____________________________________________ 50 4.1.3 Loading Protocol ___________________________________________ 51 4.2 Experimental Results ____________________________________ 55 4.2.1 Damage Observations _______________________________________ 55 4.2.2 Test 11 – Response to the Kobe 1995 Earthquake _________________ 55 4.2.3 The Effect of Load History on Reinforcement Bar Buckling _________ 58 4.3 Spread of Plasticity _____________________________________ 63 4.3.1 Test 16 – Deformation Components Three Cycle Set Load History with #3 Spiral at 1.5” (38mm) _______________________________________ 63 4.3.2 Measured Spread of Plasticity _________________________________ 69 4.4 Conclusions ___________________________________________ 70 Chapter 5: Impact of Steel Content, Aspect Ratio, and Axial Load Ratio on Column Performance ________________________________________________ 72 5.1 Test Setup and Instrumentation ____________________________ 73 5.2 Symmetric Three-Cycle-Set Loading Protocol ________________ 75 5.3 Gradual Bar Buckling Mechanism with Inelastic Transverse Steel Restraint ______________________________________________ 78 5.3.1 North Reinforcement ________________________________________ 79 5.3.2 South Reinforcement ________________________________________ 81 5.4 Transverse Steel Detailing Variable Experiments ______________ 85 5.5 Aspect Ratio Variable Experiments _________________________ 90 5.6 Longitudinal Steel Content Variable Experiments _____________ 92 5.7 Axial Load Ratio Variable Experiments _____________________ 95 5.8 Equivalent Viscous Damping _____________________________ 98 5.9 Conclusions __________________________________________ 102 Chapter 6: Bridge Column Response Prediction Techniques ______________ 104 6.1 Background and Motivation _____________________________ 104 6.1.1 Experimental Program ______________________________________ 104 6.2 Measured Deformation Components _______________________ 107 6.3 Response Prediction Methods ____________________________ 111 6.3.1 Sectional Response Prediction _______________________________ 112 6.3.2 Member Response Prediction ________________________________ 113 6.3.3 Motivation for a New Equivalent Curvature Distribution ___________ 116 Chapter 7: Modified Plastic Hinge Method _____________________________ 118 7.1 Goals for the Modified Plastic Hinge Method ________________ 118 7.2 Deformation due to Strain Penetration of Reinforcement into Adjoining Members ____________________________________ 120 7.3 Tensile and Compressive Plastic Hinge Lengths _____________ 128 7.4 Tensile Strain-Displacement Predictions using the Modified Plastic Hinge Method ________________________________________ 149 7.5 Compressive Strain-Displacement Predictions using the Modified Plastic Hinge Method __________________________________ 152 7.6 Elastic Force-Deformation Predictions using the Modified Plastic Hinge Method ________________________________________ 157 7.7 Conclusion ___________________________________________ 160 Chapter 8: Performance Strain Limits for Circular Bridge Columns _______ 183 8.1 Background __________________________________________ 183 8.2 Experimental Program __________________________________ 186 8.2.1 Loading Protocol __________________________________________ 188 8.3 Observed Damage Sequence _____________________________ 189 8.4 Equation to Predict Peak Tension Strain Prior to Bar Buckling Upon Reversal of Load ______________________________________ 193 8.5 Column Deformation at Peak Tensile Strain Prior to Bar Buckling ____________________________________________________ 197 8.6 Berry (2006) Statistical Drift-Based Bar Buckling Model for Circular Bridge Columns _______________________________________ 200 8.7 Berry (2006) Bar Buckling Model Applied to the Goodnight et al. Dataset ______________________________________________ 202 8.8 Evaluation of Strain Based Bar Buckling Predictions for the Berry (2006) Dataset ________________________________________ 204 8.9 Drift Based Approach Considering Combined Berry (2006) and Goodnight et al. Datasets ________________________________ 208 8.10 Feng (2013) Bar Buckling Strain Limit Expressions from Finite Element Analysis ______________________________________ 211 8.11 Bar Buckling Predictions for the Combined Berry (2006) and Goodnight et al. Dataset ________________________________ 221 8.12 Evaluation for Full Scale Column Experiments by Cheok and Stone (1989) _______________________________________________ 223 8.13 Compressive Strain at Cover Concrete Crushing _____________ 226 8.14 Compressive Strain at Spiral Yielding in Confinement Regions of the Column ______________________________________________ 227 8.15 Residual Crack Widths _________________________________ 232 8.16 Conclusion ___________________________________________ 234 Chapter 9: Design Recommendations for Limit State Displacements ________ 238 9.1 Performance Strain Limits _______________________________ 238 9.1.1 Serviceability Limit States __________________________________ 239 9.1.2 Intermediate Compressive Limit State _________________________ 239 9.1.3 Damage Control Limit States ________________________________ 240 9.2 Modified Plastic Hinge Method ___________________________ 244 9.2.1 Strain Penetration Length and Tension/Comp. Plastic Hinge Lengths _ 248 9.2.2 Elastic Displacements for a Column in Single Bending ____________ 249 9.2.3 Elastic Displacements for a Column in Double Bending ___________ 249 9.2.4 Inelastic Displacements for a Column in Single Bending ___________ 250 9.2.5 Inelastic Displacements for a Column in Double Bending __________ 250 Chapter 10: Future Research on the Effects of Seismic Load Path __________ 251 10.1 Problem Statement _____________________________________ 251 10.2 Background __________________________________________ 251 10.3 Brief Load Path Literature Review ________________________ 260 10.3.1 Yuk-Lung Wong, T. Paulay, and M. J. Nigel Priestley (1993). “Response of Circular Reinforced Concrete Columns to Multi-Directional Seismic Attack” __________________________________________________ 260 10.3.2 E. Osorio, J.M. Bairán, and A.R. Marí (2012). “Effects of Biaxial Shear Loading on the Seismic Response of RC Columns” _______________ 261 10.3.3 Kazuhiro Tsuno and Robert Park (2004). “Experimental Study of Reinforced Concrete Bridge Piers Subjected to Bi-Directional Quasi-Static Loading” ________________________________________________ 263 10.3.4 Stathis N. Bousias, Guido Verzeletti, Michael N. Fardis, Eugenio Gutierrez (1995). “Load Path Effects in Column Biaxial Bending with Axial Force” 266 10.4 Study Objectives ______________________________________ 268 10.5 Research Plan _________________________________________ 268 10.5.1 Task One: Detailed Literature Review _________________________ 268 10.5.2 Task Two: Load Path Analysis _______________________________ 269 10.5.3 Task Three: Experimental Studies on Columns __________________ 269 10.5.4 Task Four: Analysis of Data and Model Calibration _______________ 274 10.5.5 Task Five: Recommendations ________________________________ 274 REFERENCES ____________________________________________________ 275 Volume 2: LIST OF TABLES ___________________________________________________ x LIST OF SELECTED NOTATIONS __________________________________ xiv Chapter 1: Experimental Observations __________________________________ 1 1.1 Load History Variable Tests 8-12 ___________________________ 1 1.1.1 Test 9 – Symmetric Three Cycle Set Load History __________________ 6 1.1.2 Tests 8 and 8b – Chile 2010 Earthquake and Cyclic Aftershock LH ___ 35 1.1.3 Tests 10 and 10b – Chichi Earthquake and Cyclic Aftershock LH _____ 61 1.1.4 Test 11 – Kobe 1995 Earthquake Load History ___________________ 89 1.1.5 Test 12 – Japan 2011 Earthquake Load History __________________ 108 1.2 Load History and Transverse Steel Variable Tests 13-18 _______ 131 1.2.1 Test 13 –Three Cycle Set Load History with #4 Spiral at 2.75” (1.3%) 135 1.2.2 Test 14 –Three Cycle Set Load History with #3 Spiral at 4” (0.5%) __ 160 1.2.3 Test 15 – Three Cycle Set Load History with #3 Spiral at 2.75” (0.7%) 187 1.2.4 Test 16 – Three Cycle Set Load History with #3 Spiral at 1.5” (1.3%) 215 1.2.5 Test 17 – Chile 1985 Earthquake LH with #3 Spiral at 1.5” (1.3%) ___ 241 1.2.6 Test 18 – Darfield NZ 2010 EQ LH with #3 Spiral at 1.5” (1.3%) ____ 274 1.3 Aspect Ratio and Axial Load Variable Tests 19-24 ___________ 304 1.3.1 Test 19 – Aspect Ratio of 5.33 and 10% Axial Load ______________ 308 1.3.2 Test 20 – Aspect Ratio of 5.33 and 5% Axial Load _______________ 336 1.3.3 Test 21 – Aspect Ratio of 7.33 and 5% Axial Load _______________ 365 1.3.4 Test 22 – Aspect Ratio of 7.33 and 10% Axial Load ______________ 395 1.3.5 Test 23 – Aspect Ratio of 8.67 and 5% Axial Load _______________ 425 1.3.6 Test 24 – Aspect Ratio of 8.67 and 10% Axial Load ______________ 455 1.4 Steel Content and Axial Load Variable Tests 25-30 ___________ 488 1.4.1 Test 25 – 24” Dia. Column with 2.1% Long. Steel and 5% Axial Load 492 1.4.2 Test 26 – 24” Dia. Column with 2.1% Long. Steel and 10% Axial Load 525 1.4.3 Test 27 – 24” Dia. Column with 1.6% Long. Steel and 10% Axial Load 561 1.4.4 Test 28 – 18” Dia. Column with 1.7% Long. Steel and 15% Axial Load 598 1.4.5 Test 29 – 18” Dia. Column with 1.7% Long. Steel and 20% Axial Load 635 1.4.6 Test 30 – 18” Dia. Column with 3.1% Long. Steel and 15% Axial Load 671 Chapter 2: Weldability of A706 Reinforcing Steel _______________________ 707 2.1 Test 7 and Weldability of A706 Reinforcing Steel ____________ 707 2.2 A706 Steel Properties and Weldability for Tests 1-6 and 7-12 ___ 712 2.3 Conclusion ___________________________________________ 713 Chapter 3: Summary of Column Tests 1-6 ______________________________ 717 3.1 Test Setup and Instrumentation for Specimens 1-6 ____________ 717 3.2 Test 1: Pushover Load History ___________________________ 720 3.3 Test 2: Three-Cycle-Set with Full Cover Concrete ____________ 722 3.4 Test 3: Three-Cycle-Set with Cover Blockouts _______________ 727 3.5 Test 4: 1940 El Centro Earthquake Load History _____________ 731 3.6 Test 5: 1978 Tabas Earthquake Load History ________________ 737 3.7 Test 6: 1978 Tabas Earthquake Load History ________________ 744 REFERENCES ____________________________________________________ 748 Volume 3: Chapter 1: Introduction ____________________________________________________ 1 1.1 Background and Scope ___________________________________________ 1 1.2 Layout of Report ________________________________________________ 2 Chapter 2: Literature Review _______________________________________________ 3 2.1 General Discussion ______________________________________________ 3 2.2 Relevant Articles on Numerical Simulation ___________________________ 3 2.2.1 Fiber-Based Modeling of Reinforced Concrete Members ____________ 3 2.2.2 Finite Element Method for Reinforcing Bar Buckling _______________ 8 2.3 Chapter Summery _______________________________________________ 9 Chapter 3: Fiber-Based Modeling of Circular Reinforced Concrete Bridge Columns 10 3.1 Introduction and Background _____________________________________ 10 3.2 Theory of Fiber-Based Modeling __________________________________ 12 3.3 Proposed methods for simulating RC bridge columns __________________ 18 3.3.1 Experimental Observation ____________________________________ 18 3.3.2 Proposed Method to Predict Strain Gradient ______________________ 22 3.3.3 Method to Include Strain Penetration ___________________________ 26 3.3.4 Benchmark Method to Capture Nonlinearity in RC Member with Fiber-Based Model 29 3.4 Calibration and Application of the Fiber Model _______________________ 30 3.4.1 Calibration on Material Constitutive Models _____________________ 31 3.4.2 Prediction on Force and Strain from Static Tests __________________ 32 3.4.3 Prediction on Response of Shake Table Tests _____________________ 42 3.5 Chapter Conclusions ____________________________________________ 44 Chapter 4: Load History Effect on Relationship between Strain and Displacement __ 45 4.1 General Discussion _____________________________________________ 45 4.2 Ground

Initial validation of a virtual blood draw exposure paradigm for fear of blood and needles

Fear of blood, injections, and needles commonly prevents or delays individuals' receipt of health care, such as vaccines or blood draws. Innovative methods are needed to overcome these fears and reduce anxiety related to activities of this nature. The present study describes initial testing of an arm illusion paradigm that may prove useful during early phases of graded exposure for people with blood and needle fear. Seventy-four undergraduate students aged 18-29 years were tested. In line with study aims, results indicated that the virtual blood draw paradigm promoted strong perceptions of arm ownership and elicited significant changes in physiological indices (blood pressure, heart rate, electrodermal activity, respiratory rate) in response to key procedure elements (e.g., needle insertion). Further, bivariate correlations indicated that individual differences in self-reported blood and needle fear collected prior to the illusion paradigm were significantly associated with presyncopal symptoms reported following the procedure. In regression analyses, self-reported measures of blood and needle fear explained unique variance in presyncopal symptoms even after controlling for general state anxiety. These findings provide initial support for the virtual blood draw paradigm as a promising tool to help provide graded exposure to medical procedures involving needles and blood draw

Acute vs. Chronic Citrulline Malate Supplementation on Muscle Fatigue

Citrulline malate has been proposed to aid in reducing fatigue by increasing blood flow through promoting an increase in the nitric oxide synthase pathway along with the ability to remove ammonia and lactate accumulations. Results on the effectiveness of an acute supplementation are mixed, but it is proposed that regular consumption may help to attenuate the onset of fatigue during exercise. PURPOSE: To investigate the effects of acute and chronic citrulline malate supplementation on fatigue rate of the quadriceps. METHODS: Recreationally trained males (n=18, 24±5 yr, 83±14 kg, 174±6 cm) participated in seven testing sessions. The familiarization session consisted of participants performing a graded exercise test to determine max power output. In a randomized, counterbalanced order, participants consumed a placebo (PL) and citrulline malate (CM) treatment for two separate dosing periods. For each dosing period, participants reported on three separate days with seven days between each visit. The first experimental testing session for each dosing period was considered the baseline day (BL), the second session the acute day (D1), and the third session the chronic day (D2). For chronic supplementation, all participants consumed each treatment for seven consecutive days. The exercise protocol all testing sessions and the four supplemental testing sessions included exercising on a cycle ergometer at 50-60% of their max power output for 30 min. Following the bout, all participants performed the Thorstensson test on an isokinetic dynamometer for torque, power, and fatigue rate of the dominate leg quadriceps. RESULTS: The acute supplement x time interactions were not significant (p\u3e0.05) for peak power (PL BL 469+81 W, PL D1 490+97 W vs. CM BL 465+85 W, CM D1 480+103 W), peak torque (PL BL 150+26 Nm, PL D1 157+32 Nm vs. CM BL 149+26 Nm, CM D1 156+33 Nm), fatigue rate (PL BL 57+9%, PL D1 57+10% vs. CM BL 57+10%, CM D1 56+9%), and heart rate (PL BL 156+17 bpm, PL D1 146+13 bpm vs. CM BL 155+11 bpm, CM D1 146+11 bpm). The chronic supplement x time interactions were not significant (p\u3e0.05) for peak power (PL BL 469+81 W, PL D2 501+99 W vs. CM BL 464+85 W, CM D2 501+81 W), peak torque (PL BL 150+26 Nm, PL D2 161+31 Nm vs. CM BL 149+27 Nm, CM D2 161+26 Nm), fatigue rate (PL BL 57+9%, PL D2 58+9% vs. CM BL 57+10%, CM D2 58+9%), and heart rate (PL BL 156+17 bpm, PL D2 146+9 bpm vs. CM BL 155+11 bpm, CM D2 146+9 bpm). CONCLUSION: The results of this study suggest that neither acute or chronic supplementation of CM had an effect on recovery or fatigue rate of the quadriceps. Based on the data collected there were no significant differences between the recorded values for torque and power for each participant

Cognitive chicken or the emotional egg? How reconceptualizing decision-making by integrating cognition and emotion can improve task psychometrics and clinical utility

Decision-making is an executive function, tapping into cognitive, emotional, and personality-based components. This complexity, and the varying operational definitions of the construct, is reflected in the rich array of behavioral decision-making tasks available for use in research and clinical settings. In many cases, these tasks are “subfield-specific,” with tasks developed by cognitive psychologists focusing on cognitive aspects of decision-making and tasks developed by clinical psychologists focusing on interactions between emotional and cognitive aspects. Critically, performance across different tasks does not consistently correlate, obfuscating the ability to compare scores between measures and detect changes over time. Differing theories as to what cognitive and/or emotional aspects affect decision-making likely contribute to this lack of consistency across measures. The low criterion-related validity among decision-making tasks and lack of consistent measurement of the construct presents challenges for emotion and decision-making scholars. In this perspective, we provide several recommendations for the field: (a) assess decision-making as a specific cognitive ability versus a taxonomy of cognitive abilities; (b) a renewed focus on convergent validity across tasks; (c) further assessment of test–retest reliability versus practice effects on tasks; and (d) reimagine future decision-making research to consider the research versus clinical implications. We discuss one example of decision-making research applied to clinical settings, acquired brain injury recovery, to demonstrate how some of these concerns and recommendations can affect the ability to track changes in decision-making across time