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Verification of the Correlation Between Peak Particle Velocity (PPV) and the Response of a Structure

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Verification of the Correlation Between Peak Particle Velocity (PPV) and the Response of a Structure University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 8-2004 Verification of the Correlation between Peak Particle Velocity (PPV) and the Response of a Structure Sagar Ramesh Kulkarni University of Tennessee, Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Civil and Environmental Engineering Commons Recommended Citation Kulkarni, Sagar Ramesh, "Verification of the Correlation between Peak Particle Velocity (PPV) and the Response of a Structure. " Master's Thesis, University of Tennessee, 2004. https://trace.tennessee.edu/utk_gradthes/4629 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Sagar Ramesh Kulkarni entitled "Verification of the Correlation between Peak Particle Velocity (PPV) and the Response of a Structure." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Civil Engineering. Earl E. Ingram, Major Professor We have read this thesis and recommend its acceptance: Harold Deatherage, Edwin G. Burdette, David W. Goodpasture Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I amsubmitting herewith a thesis written by Sagar RameshKulkarni entitled "Verificationof the Correlationbetween Peak ParticleVelocity (PPV) andthe Response of a Structure." I have examinedthe finalpaper copy of this thesis for formand content and recommend that it be accepted in partial fulfillmentof the requireme r the degree of Master of Science, with a major in Civil Engineering. Dr. Earl E. Ingram,Major Professor Vice Chancell� Graduate Studies VERIFICATION OF THE CORRELATION BETWEEN PEAK PARTICLE VELOCITY (PPV) AND THE RESPONSE OF A STRUCTURE A Thesis Presented forthe Master of Science Degree The University of Tennessee, Knoxville SagarRamesh Kulkarni August 2004 This thesis is dedicated to my mother Smt. Smita Ramesh Kulkarni 111 Acknowledgements I shall takethe opportunity to express my gratitudeto the members of my committee fortheir support during this endeavor. I amespecially thankfulto my major professor,Dr. Earl E. Ingram,for his guidance,constructive criticism with a superb rapport all the way. I would also like to thank Dr. Edwin G. Burdette whose guidance, financialsupport and confidencein me made everything work out. I am certainly grateful to Dr. David. W. Goodpasture, Dr. Richard M. Bennett, Dr. Eric C. Drumm and Dr. J Harold Deatherage forthe knowledge I gathered fromthem inside, as well as outside, the classroom. Thanksto all formaking my learningprocess a pleasure. This Master's Degreewould not have been possible without the endless prayers andblessings, forme, ofmy uncles Prakash Gupte, Kiran Gupte, my aunt Rajani·Gupte, my beloved grandmotherMalati Gupte andrest of my family. My special thanksto Potdar and Parulekar familyfor turning the partingsinto a cheerfulencouragement. Finally, I would like to share my success with my friend Dr. Milind Gharpure; with whom I could always take things forgranted. His calm, thoughtfuland continuous encouragement throughout my highs andlows nourished me until I got here. Thankseverybody forbeing there. Cheers!!! V Abstract The purposeof this study is to verifythe relation between the peakparticle velocity (PPV) andthe dynamicresponse of the structure. Based on the study of blast vibrations, the U.S Bureau of Mines correlatedthe PPV as the reliable parameter for gauging the strength of a blast wave. The prevalent practice of quantifyingthe ground wave motion is in termsof PPV. The bureau haspublished the threshold value of PPV=l/2 in/sec as the maximum safevalue for a blast wave. This study simulates two structures having two differentnatural periods resembling the period of shortbuildings andmedium heightbuildings. The simulation is done using finite element models in ADINAto study the response of the two structures for various ground accelerations while keeping the value of PPV constant.The process is repeated fora constant acceleration while varyingthe magnitudeof PPV. Based on the results of these finiteelement models it is observedthat the response is closely proportional to the PPV rather thanthe ground acceleration. Hence PPV appearsto be the correctterm to represent the strength of ground motion. vu TABLE OF CONTENTS CHAPTER 1. INTRODUCTION AND OVERVIEW OF SOLUTION 1 Introduction 1 Overview of solution 2 2. REVIEW OF LITERATURE 5 History 5 Evolution of PPV 7 Monitoring of PPV 8 Currentlyused safe values of PPV 11 Frequency influence andresponse spectra 13 Response spectraanalysis 14 3. LABORATORY TEST 17 Determination of dampingratio 17 Conclusion 19 4. FINITE ELEMENT MODEL 23 Introduction 23 Model specifics 23 Model cases generated 28 5. RESULTS AND CONCLUSION 31 Discussion on results 31 Conclusion 38 Potential furtherresearch 38 WORKCONSULTED 41 APPENDIX A FINITE ELEMENT SIMULATION MODEL 47 APPENDIX B PERMIT FROM 'PEARSON EDUCATION' 67 Vita 71 lX LIST OF TABLES TABLE-2-1 Typeof structure andits empirical natural frequency 13 XI LIST OF FIGURES FIGURE-2-1 Comparison Between Ground Velocity 15 And Struc.Velocity FIGURE-2-2 Comparison Between Ground Acceleration 16 And Struc. Acceleration FIGURE-3-1 Assembly For DeterminingCoefficient For Damping 18 FIGURE-3-2 Details Of Specimen Structure 18 FIGURE-3-3 Strain Vs. Time (For½" Plate At Top) 20 FIGURE-3-4 Strain Vs Time (For 2" Plate At Top) 21 FIGURE- 4-1 Typical Adina Model 24 FIGURE- 4-2 Calculations Of DynamicProperties For 25 ½" Thick Plate Structure FIGURE- 4-3 Calculations Of DynamicProperties For 26 2" Thick Plate Structure FIGURE-4-4 Permutation Combination Models Generated In FEA 28 FIGURE-4-5 Schematic PlanFor TypeOf Models Generated 29 In Adina FIGURE-5-1 Model-1, Model-2, Model-3 32 FIGURE-5-2 Model-4, Model-5, Model-6 33 FIGURE-5-3 Model-7, Model-8, Model-9 34 FIGURE-5-4 Model-10, Model-11, Model-12 35 FIGURE-5-5 Model-13, Model-14, Model-15 36 xm FIGURE-5-6 Model-16, Model-17, Model-18 37 FIGURE-5-7 ½" Plate At Top - Ground Acceleration And 39 Struct. Response For VariousPPV FIGURE-5-8 2" Plate At Top - Ground Acceleration And 40 Struct. Response For VariousPPV FIGURE-A-I Model-I 49 FIGURE-A-2 Model-2 50 FIGURE-A-3 Model-3 51 FIGURE-A-4 Model-4 52 FIGURE-A-5 Model-5 53 FIGURE-A-6 Model-6 54 FIGURE-A-7 Model-7 55 FIGURE-A-8 Model-8 56 FIGURE-A-9 Model-9 57 FIGURE-A-IO Model-IO 58 FIGURE-A-11 Model-11 59 FIGURE-A-12 Model-12 60 FIGURE-A-13 Model-13 61 FIGURE-A-14 Model-14 62 FIGURE-A-15 Model-15 63 FIGURE- A-16 Model-16 64 FIGURE-A-17 Model-17 65 FIGURE-A-18 Model-18 66 XIV CHAPTERl INTRODUCTION AND OVERVIEW OF SOLUTION Introduction The repeated explosions that occur in quarries andmines have historically been a nuisance forpeople residing in the vicinity. The nuisanceis in the formof vibrations that potentially cause structuraldamage. In 1930, the U.S Bureau of Mines initiated an extensive study to determinethe variousparameters influencing structural damage from blasting. There were two majortypes of damagingsources associated with the blasts; one was throughthe groundvibrations andanother was the air blast. This thesis discusses damagedue to the groundvibrations anddoes not address the air blast or any other source of structuraldamage. In this study by the Bureau, structural damagethreshold values were identifiedwhich would be irrespectiveof anyblast. Structural damagesover andabove thesethreshold values were inspected andwere correlatedwith the "strength" of the blast. The Bureau reports introduced a concept called "Peak ParticleVeloci ty'' (PPV) to quantifythe "strength"of a blast. The magnitudeof structural damagewas then correlatedto the PPV of the groundexcitation. Guidelines were then developed to regulate blast strengthssuch that a PPV threshold is not exceeded. Regulating blast strength based solely on PPV does not takeinto consideration the peak particle acceleration of the motion wave. It may happen that the peak particlevelocity regulated by the miners is well within the safepermissible limit but the peak particle acceleration may cause a response of the structureabove the safetylimits. Hence the 1 question arisesas to whether the response is related to the peakparticle velocity or peak particleacceleration. The finiteelement simulation research conducted at the University of Tennessee using the permissiblevalue ofPPV investigates the validity of the popular correlation between the response andpeak particlevelocity . Overview of solution In order to understandthe exact correlation between the PPV andthe response of the structure, it is importantto develop andanswer a set of questions which would act as the road map forthis thesis. A key question is; forvarying groundaccelerations, do both structures react the same way to a given PPV. Keeping all the other parametersconstant, the correlation between the PPV and response can be determined.The correlation can be easily represented by plotting the response vs. ground acceleration under the constant PPV. According to the currenttheory,
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