Foundations Subjected to Vibration Loads
|
|
- Edgar Howard Hill
- 5 years ago
- Views:
Transcription
1 Foundations Subjected to Vibration Loads A practical design tool for sizing equipment mats By Leonel I. Almanzar Micheli and halid Motiwala The structural design of a foundation system supporting dynamic equipment is complicated by the need to model the periodic load, foundation, and soil conditions; calculate the structural response of the system; and interpret the resulting displacements. Designers therefore may follow historical rules of thumb for example, ensuring that the total weight of the mat foundation (slab) is three times the weight of a rotating machine or five times the weight of a reciprocating machine 1 but these rules may lead to oversized foundations. To obtain an optimum slab size while avoiding resonance with the supported machine and ensuring minimal human perception of vibrations, it s important to track a slab s natural frequency and its displacement amplitudes. In this article, we present practical guidelines and recommendations for design of slabs subject to induced vibration forces from steady-state frequency equipment without vibration isolators. Using graphs and tables, we also show the effects of changes in dimensions of the foundation, operational speed of the equipment, and modulus of subgrade reaction on a slab s natural frequency and peak displacement. FOUNDATION MODEL A finite element model incorporating 4-node plate elements with linear spring supports located at each node was used to find the natural frequencies and vibration amplitudes for slabs (Fig. 1). Slab thickness, corrected modulus of subgrade reaction, and distributed equipment weight values were varied to develop parametric curves. Thickness values were varied from 6 to 48 in. (150 to 100 mm), modulus values were varied from 5 to 00 kip/ft 3 (3.93 to 31.5 MPa/m), and distributed equipment weight values were varied from 0 to 500 lb/ft (0 to 4 kpa). In addition to equipment weight, models included induced vibration forces uniformly distributed over the slab area. MODEL PARAMETERS Slab and subgrade The slab was modeled as an isotropic material with gross section properties. The modulus of elasticity was assumed to be 3605 ksi (4,900 MPa). Elements sizes were constant at 1 x 1 ft (0.3 x 0.3 m) except when varied to verify convergence of the results. The modulus of subgrade reaction from a 1 x 1 ft (0.3 x 0.3 m) reaction plate test, 1, must be corrected for the size and configuration of the actual foundation. First, the corrected subgrade modulus for a B x B foundation, where B is the smaller of the actual foundation plan dimensions in ft (m), is determined using one of the following two equations. For sandy soils: B + 1 ft B B m For clays: 1 1 B B 1 3.8B (1) (1) () () 4 July 009 / Concrete international
2 Fig. 1: Finite element model used for dynamic analysis of a mat foundation s response to a vibrating load The corrected subgrade modulus for a B x L foundation, where L is the larger of the actual foundation plan dimensions in ft (m), is then determined from the following equation Fig. : Example of natural frequency results from finite element analysis of a 10 x ft (3 x 6.7 m) mat foundation with varying slab thickness and subgrade modulus (1 in. 5.4 mm; 1 kip/ft MPa/m) B L 1.5 The spring stiffness in the model was equal to the tributary area of a node multiplied by. Dynamic load and damping The system was subjected to a vibrating load F that followed the function 3 (3) F F sin (ω t) (4) o where F o is the amplitude of the vibrating force in lb (kn), ω is the operating speed of the equipment in rad/s, and t is time in seconds. To compute the amplitude of the vibrating force to be transmitted to the foundation, the following equation can be used 4 F W g r o eω (5) where W r is the weight of equipment engine in lb (N), g is the acceleration due to gravity taken as in./s (9.81 m/s ), ω is the operating speed of the equipment in rad/s, and e is the eccentricity of unbalanced mass in inches (m). When e is not known and the operating speed of the equipment is less than 5,000 rpm (60 rad/s), e can be approximated by 0.5/ω in inches ( /ω in meters). The internal damping of the soil was approximated using a conservative value of % of critical damping. 5 NATURAL FREQUENCY Only the first three mode shapes and frequencies were evaluated for the slab models. The lowest frequency value is taken as the natural frequency of the foundation. Fig. 3: Natural frequency results for a subgrade modulus of 50 kip/ft 3 (7.85 MPa/m) as a function of foundation pressure and slab thickness h (1 in. 5.4 mm; 1 lb/ft kn/m ) As shown by the natural frequency results from the model presented in Fig., the natural frequency of the system increases as the modulus of subgrade reaction increases and as the thickness of the slab decreases. Other parameters also affect the natural frequency of the system, such as the slab dimensions and the equipment weight. Therefore, two graphs have been developed to approximate the natural frequency of the actual system. For a modulus of subgrade reaction of 50 kip/ft 3 (7.85 MPa/m), Fig. 3 gives the natural frequency for a specific foundation pressure. This value is then corrected for the actual -value using the factor obtained from Fig. 4. The natural frequency of the foundation-soil system should be either less than half or at least two times the operating frequency of the equipment. 6 Concrete international / July
3 Fig. 4: Natural frequency correction factor for mat foundations when subgrade modulus is different than 50 kip/ft 3 (7.85 MPa/m) (1 kip/ft MPa/m) Fig. 5: Example of vertical displacement time history results (1 in. 5.4 mm) DYNAMIC RESPONSE The displacement time history was obtained from the finite element model. An example is shown in Fig. 5. The initial amplitude, as well as the steady-state amplitude during operation, should be recorded or observed, although the initial amplitude was always found to be larger in our results. From these values, a set of curves was developed by changing the operational speed of the equipment and the ratio of equipment weight to foundation area. Each curve represents a different slab thickness. It should be noted that the vibrating force amplitude also changes with equipment type, weight, and operating speed. Therefore, to set up typical curves, the vibrating force amplitude was fixed at 5% of the total equipment weight for the development of the curves. Figure 6 shows initial amplitude curves for a modulus of subgrade reaction of 50 kip/ft 3 (7.85 MPa/m) and an equipment operating speed of 1800 rpm. The displacement amplitude from Fig. 6 is corrected for the actual operating speed, force amplitude, and subgrade modulus using the following equation CIRCLE READER CARD #1 A f A C C C (6) o July 009 / Concrete international
4 Fig. 6: Initial vertical displacement amplitude for a 50 kip/ft 3 (7.85 MPa/m) subgrade modulus and an 1800 rpm equipment operating speed for various slab thicknesses h (1 in. 5.4 mm; 1 lb/ft kn/m ) 1/3 Vert. where A f is the corrected amplitude in inches (m), A o is the amplitude obtained from Fig. 6 in inches (m), C 1 is the operating speed correction factor from Fig. 7, C is the force amplitude correction factor from Fig. 8, and C 3 is the modulus of subgrade reaction correction factor from Fig. 9. EXAMPLE The following example demonstrates the use of the method and figures presented in this article for the design of a 000 kw generator foundation. The following equipment and soil data are known: Total generator weight W 38,155 lb (169.7 kn); Engine weight W r 17,885 lb (79.6 kn); Operating frequency 1800 rpm 30 Hz rad/s; Foundation rests on sandy soil with 1x1 5 kip/ft 3 (35.3 MPa/m); Eccentricity e in. ( m); Total generator length 1 ft (6.4 m); and Generator width 7.75 ft (.36 m); Based on the generator dimensions, the foundation is initially estimated to be x 11 ft (6.7 x 3.35 m). Using Eq. (1) and (3), the modulus of subgrade reaction is corrected for the actual foundation size: 3 3 B + 1 ft 11 ft + 1 ft 5 kip/ft kip/ft B (11 ft) B m 3.35 m m 35.3 MPa/m MPa/m B (3.35 m) B 11 ft L kip/ft ft kip/ft B 3.35 m L MPa/m 6.7 m 8.73 MPa/m CIRCLE READER CARD #13 Concrete international / July
5 Fig. 7: Displacement amplitude correction factor C 1 for operating speeds other than 1800 rpm Next, the natural frequency is found from Fig. 3. The foundation area is 11 ft ft 4 ft (3.35 m 6.7 m.45 m ), and the total equipment weight/foundation area is 38,155 lb/4 ft lb/ft (169.7 kn/.45 m 7.56 kn/m ). The authors recommend that the initial trial analysis foundation weight be at least 1.3 to 1.5 times the total equipment weight. Therefore, an initial thickness of 30 in. (0.76 m) is used. From Fig. 3, the natural frequency for 50 kip/ft 3 (7.85 MPa/m) is 8.8 Hz. The natural frequency from Fig. 3 must be corrected using the factor from Fig. 4, which is 1.04 for an actual of kip/ft 3 (8.73 MPa/m). Therefore, the natural frequency for the system is Hz 9.15 Hz. As mentioned, it s recommended that the natural frequency be less than half or more than twice the equipment operating frequency. For this example, the ratio of natural to operating frequency is 9.15 Hz/30 Hz Therefore, the selected foundation size meets the criteria. Now, the displacement amplitude can be determined. Using Fig. 6, the initial displacement amplitude A o is in. ( m) for an equipment weight/foundation area of lb/ft (7.56 kn/m ). This amplitude must be corrected using Fig. 7, 8, and 9. For an operating speed of 1800 rpm, Fig. 7 gives a correction factor C To find correction factor C, the force amplitude F o must be calculated using Eq. (5) ω Fig. 8: Displacement amplitude correction factor C for force amplitudes other than 5% of the total equipment weight ω Fig. 9: Displacement amplitude correction factor C 3 for subgrade moduli other than 50 kip/ft 3 (7.85 MPa/m) (1 kip/ft MPa/m) From Fig. 8, the force amplitude correction factor C From Fig. 9, the modulus of subgrade reaction factor C for kip/ft 3 (8.73 MPa/m). The corrected initial displacement amplitude A f A o C 1 C C in in. ( m m). This vibration amplitude is compared to the allowable vibration amplitudes shown in Fig to determine the adequacy of the foundation in terms of vibration perception. The initial vibrating amplitude of the generator foundation will be noticeable to people. This occurs, however, only for a short time, and it s not considered to be transmitted to nearby structures. The operating amplitude depends 46 July 009 / Concrete international
6 References 1. ACI Committee 351, Foundations for Dynamic Equipment (ACI 351.3R-04), American Concrete Institute, Farmington Hills, MI, 004, 63 pp.. Das, B.M., Principles of Foundation Engineering, fifth edition, Thomson/Brooks/Cole, Pacific Grove, CA, 004, pp Wolf, J.P., Foundation Vibration Analysis Using Simple Physical Models, PTR Prentice Hall, Englewood Cliffs, NJ, 1994, 43 pp. 4. Arya, S.C.; O Neill, M.W.; and Pincus, G., Design of Structures and Foundations for Vibrating Machines, Gulf Publishing Co., Houston, TX, 1979, 191 pp. 5. Whitman, R.V., and Richart, F.E. Jr., Design Procedures for Dynamically Loaded Foundations, University of Michigan, Ann Arbor, MI, 1967, 53 pp. 6. Das, B.M., Principles of Soil Dynamics, PWS-ent Publishing Co., Boston, 1993, pp Selected for reader interest by the editors after independent expert evaluation and recommendation. Fig. 10: Suggested allowable combinations of foundation vibration amplitude and vibration frequency (after Reference 5) (1 in. 5.4 mm) on the damping of the system, but can be estimated to be about 1/5 to 1/3 the initial amplitude when % of critical damping is used. Suggestions During design of mat foundations subjected to vibrating load, the following recommendations should be taken into consideration: To avoid resonance in vibrating machinery with low operating speed, the natural frequency should be at least two times the operating frequency; To avoid resonance in vibrating machinery with high operating speed, the natural frequency be no more than half the operating frequency; When vibrating force amplitude cannot be obtained, at least 10% of the weight of the rotating machine should be considered 5 ; When data are not available, the internal damping of soil can be approximated using % of critical damping; and The system should be designed to have a maximum displacement amplitude response in the range of barely to easily noticeable to people to avoid human discomfort. Leonel I. Almanzar Micheli is a Senior Structural Engineer in AECOM s Orlando, FL, office. He received a BS in civil engineering from Technological Institute of Santo Domingo and an MS in structural engineering and a PhD in structural engineering from the University of Puerto Rico. He is a member of the ASCE-7 Main Committee and Special Project Chair of the SEI-Central Florida Chapter. He has experience in analysis, design, and preparation of preliminary plans and final contract plans, and the management of construction services for water and wastewater treatment facilities, dams, and transportation structures. ACI member halid Motiwala is a Principal Structural Engineer in AECOM s Orlando, FL, office. He received a BS in civil engineering from the University of Central Florida. He has served as a professional engineer in the areas of structural design of water and wastewater treatment facilities, pump stations, box culverts, retaining walls, industrial, and manufacturing facilities, as well as assessment of existing infrastructure and facility engineering. He is a member of ACI Committee 350, Environmental Engineering Concrete Structures, and subcommittees 350A, General and Concrete, and 350D, Structural. In addition, he is the current President of the ACI Central Florida Chapter. Concrete international / July
Dowels for the 21st Century
Dowels for the 21st Century by Wayne W. Walker and Jerry A. Holland sing plate dowels in slabs on ground for shear load transfer at the joints offer many advantages over the traditional round dowels. By
More informationINFLUENCE OF PILES ON LOAD- SETTLEMENT BEHAVIOUR OF RAFT FOUNDATION
INFLUENCE OF PILES ON LOAD- SETTLEMENT BEHAVIOUR OF RAFT FOUNDATION BALESHWAR SINGH Department of Civil Engineering Indian Institute of Technology Guwahati Guwahati 78139, India NINGOMBAM THOIBA SINGH
More informationEffect of Braces on Framed Machine Foundation for Turbo Generator
nternational Journal of Current Engineering and Technology E-SSN 2277 4106, P-SSN 2347 5161 2017 NPRESSCO, All Rights Reserved Available at http://inpressco.com/category/ijcet Research Article S.A. Halkude
More informationPREDICTION OF RAILWAY INDUCED GROUND VIBRATION
inter.noise 2000 The 29th International Congress and Exhibition on Noise Control Engineering 27-30 August 2000, Nice, FRANCE Paper IN2000/467 http://confs.loa.espci.fr/in2000/000467/000467.pdf PREDICTION
More informationFB-PIER VALIDATION SET
FB-PIER VALIDATION SET Dynamics February 2004 FB-Pier Dynamics Validation Manual 1 Example 1 Single Pile Subject to a Pulse Load at the Pile Head Problem: The single 24 square prestressed concrete pile
More informationElastic Support of Machinery and Equipment
Elastic Support of Machinery and Equipment Elastic Support of Machinery and Equipment Typical Spring Unit (Load Capacity 2 to 48 kn) Principle of Vibration Isolation The transmission of periodic or shocktype
More informationMODELLING OF CONCRETE PAVEMENT DOWEL-SLAB INTERACTION
4 e Conférence spécialisée en génie des transports de la Société canadienne de génie civil 4 th Transportation Specialty Conference of the Canadian Society for Civil Engineering Montréal, Québec, Canada
More informationPreliminary study of the vibration displacement measurement by using strain gauge
Songklanakarin J. Sci. Technol. 32 (5), 453-459, Sep. - Oct. 2010 Original Article Preliminary study of the vibration displacement measurement by using strain gauge Siripong Eamchaimongkol* Department
More informationINFLUENCE OF TIE BEAMS ON THE SHALLOW ISOLATED ECCENTRIC FOOTING SYSTEM INTRODUCTION
Journal of Engineering Sciences, Assiut University, Vol. 37, No. 1, pp.51-61, January 2009 INFLUENCE OF TIE BEAMS ON THE SHALLOW ISOLATED ECCENTRIC FOOTING SYSTEM Associate Prof., Engineering & Islamic
More informationTechnical Note: Analysis of Offshore Pipeline Allowable Free Span Length. Introduction
Technical Note: Analysis of Offshore Pipeline Allowable Free Span ength Downloaded from ijce.iust.ac.ir at :3 IRST on Sunday January 3th 9 Abbas Yeganeh Bakhtiary, Abbas Ghaheri and Reza Valipour 3 Assitant
More informationA study of Vibration Analysis for Gearbox Casing Using Finite Element Analysis
A study of Vibration Analysis for Gearbox Casing Using Finite Element Analysis M. Sofian D. Hazry K. Saifullah M. Tasyrif K.Salleh I.Ishak Autonomous System and Machine Vision Laboratory, School of Mechatronic,
More informationSettlement Analysis of Piled Raft System in Soft Stratified Soils
Settlement Analysis of Piled Raft System in Soft Stratified Soils Srinivasa Reddy Ayuluri 1, Dr. M. Kameswara Rao 2 1 (PG Scholar, Civil Engineering Department, Malla Reddy Engineering College, Hyderabad,
More informationCHAPTER 5 FAULT DIAGNOSIS OF ROTATING SHAFT WITH SHAFT MISALIGNMENT
66 CHAPTER 5 FAULT DIAGNOSIS OF ROTATING SHAFT WITH SHAFT MISALIGNMENT 5.1 INTRODUCTION The problem of misalignment encountered in rotating machinery is of great concern to designers and maintenance engineers.
More informationCALIBRATION OF COMPUTER PROGRAM SASSI FOR VIBRATION TRANSMISSIBILITY ANALYSIS IN UNDERGROUND STRUCTURES USING FIELD MEASURED DATA
CALIBRATION OF COMPUTER PROGRAM SASSI FOR VIBRATION TRANSMISSIBILITY ANALYSIS IN UNDERGROUND STRUCTURES USING FIELD MEASURED DATA Frederick Tajirian Mansour Tabatabaie Fred Asiri and Andrei Seryi Chevron
More informationFATIGUE CRACK CHARACTERIZATION IN CONDUCTING SHEETS BY NON
FATIGUE CRACK CHARACTERIZATION IN CONDUCTING SHEETS BY NON CONTACT STIMULATION OF RESONANT MODES Buzz Wincheski, J.P. Fulton, and R. Todhunter Analytical Services and Materials 107 Research Drive Hampton,
More informationEarthquake response analysis of Ankara high speed train station by finite element modeling
Earthquake response analysis of Ankara high speed train station by finite element modeling Burak Nebil BARUTÇU 1 ; Salih ALAN 2 ; Mehmet ÇALIŞKAN 3 Department of Mechanical Engineering Middle East Technical
More informationVIBRATIONAL TESTING OF A FULL-SCALE PILE GROUP IN SOFT CLAY
VIBRATIONAL TESTING OF A FULL-SCALE PILE GROUP IN SOFT CLAY Marvin W HALLING 1, Kevin C WOMACK 2, Ikhsan MUHAMMAD 3 And Kyle M ROLLINS 4 SUMMARY A 3 x 3 pile group and pile cap were constructed in a soft
More informationDynamic Vibration Absorber
Part 1B Experimental Engineering Integrated Coursework Location: DPO Experiment A1 (Short) Dynamic Vibration Absorber Please bring your mechanics data book and your results from first year experiment 7
More informationVibratory Feeder Bowl Analysis
The Journal of Undergraduate Research Volume 7 Journal of Undergraduate Research, Volume 7: 2009 Article 7 2009 Vibratory Feeder Bowl Analysis Chris Green South Dakota State University Jeff Kreul South
More informationFinite Element Study of Using Concrete Tie Beams to Reduce Differential Settlement Between Footings
Finite Element Study of Using Concrete Tie Beams to Reduce Differential Settlement Between Footings AMIN H. ALMASRI* AND ZIAD N. TAQIEDDIN** *Assistant Professor, Department of Civil Engineering, Jordan
More informationNumerical Analysis of Piled Raft Foundation using Fem with Interaction Effects
International Journal of TechnoChem Research ISSN:2395-4248 www.technochemsai.com Vol.01, No.03, pp 126-134, 2015 Numerical Analysis of Piled Raft Foundation using Fem with Interaction Effects Naveen kumar.d
More informationEvaluation of Drywall Resilient Sound Isolation Clips. Dr. Peter D Antonio RPG Diffusor Systems, Inc. January 2010
Evaluation of Drywall Resilient Sound Isolation Clips by Dr. Peter D Antonio RPG Diffusor Systems, Inc. January 2010 TABLE OF CONTENTS 0 INTRODUCTION 1. THEORY 1.1 TRANSMISSIBILITY 1.2 Static stiffness
More informationFINITE ELEMENT ANALYSIS OF ACTIVE VIBRATION ISOLATION
FIFTH INTERNATIONAL w CONGRESS ON SOUND AND VIBRATION DECEMBER 15-18, 1997 ADELAIDE, SOUTH AUSTRALIA Invited Paper FINITE ELEMENT ANALYSIS OF ACTIVE VIBRATION ISOLATION Carl Q. Howard and Colin H. Hansen
More informationANALYSIS OF LATERALLY LOADED PILE GROUPS
IOSR Journal of Civil Engineering (IOSR-JMCE) ISSN: 2278-0661, ISBN: 2278-8727, PP: 60-64 www.iosrjournals.org ANALYSIS OF LATERALLY LOADED PILE GROUPS B. Manjula Devi 1, Chore H.S 1, V.A.Sawant 2 1, Department
More informationDynamic Analysis of Infills on R.C Framed Structures
Dynamic Analysis of Infills on R.C Framed Structures Manju G 1 P.G. Student, Department of Civil Engineering, Sahyadri College of Engineering and Management, Mangalore, Karnataka, India 1 ABSTRACT: While
More informationSolution of Pipeline Vibration Problems By New Field-Measurement Technique
Purdue University Purdue e-pubs International Compressor Engineering Conference School of Mechanical Engineering 1974 Solution of Pipeline Vibration Problems By New Field-Measurement Technique Michael
More informationD102. Damped Mechanical Oscillator
D10. Damped Mechanical Oscillator Aim: design and writing an application for investigation of a damped mechanical oscillator Measurements of free oscillations of a damped oscillator Measurements of forced
More informationMonitoring The Machine Elements In Lathe Using Vibration Signals
Monitoring The Machine Elements In Lathe Using Vibration Signals Jagadish. M. S. and H. V. Ravindra Dept. of Mech. Engg. P.E.S.C.E. Mandya 571 401. ABSTRACT: In any manufacturing industry, machine tools
More informationEffect of Pile Bending Stiffness on Static Lateral Behavior of a Short Monopile in Dry Sand
INTERNATIONAL JOURNAL OF COASTAL & OFFSHORE ENGINEERING JCOE No. 5/ Winter 217 (25-32) Effect of Pile Bending Stiffness on Static Lateral Behavior of a Short Monopile in Dry Sand Saeed Darvishi Alamouti
More informationB. Gurudatt, S. Seetharamu, P. S. Sampathkumaran and Vikram Krishna
, June 30 - July 2, 2010, London, U.K. Implementation of Ansys Parametric Design Language for the Determination of Critical Speeds of a Fluid Film Bearing-Supported Multi-Sectioned Rotor with Residual
More informationActive Vibration Isolation of an Unbalanced Machine Tool Spindle
Active Vibration Isolation of an Unbalanced Machine Tool Spindle David. J. Hopkins, Paul Geraghty Lawrence Livermore National Laboratory 7000 East Ave, MS/L-792, Livermore, CA. 94550 Abstract Proper configurations
More informationEffect of Infill Walls on RC Framed Structure
Effect of Infill Walls on RC Framed Structure Akshay Grover 1, Dr. S.K. Verma 2 P.G. Student, Department of Civil Engineering (Structures), PEC University of Technology, Chandigarh, India 1 Associate Professor,
More informationCalibration of Hollow Operating Shaft Natural Frequency by Non-Contact Impulse Method
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-issn: 2278-1684,p-ISSN: 2320-334X, Volume 13, Issue 2 Ver. I (Mar. - Apr. 2016), PP 54-60 www.iosrjournals.org Calibration of Hollow Operating
More informationModule 7 : Design of Machine Foundations. Lecture 31 : Basics of soil dynamics [ Section 31.1: Introduction ]
Lecture 31 : Basics of soil dynamics [ Section 31.1: Introduction ] Objectives In this section you will learn the following Dynamic loads Degrees of freedom Lecture 31 : Basics of soil dynamics [ Section
More informationStudies on free vibration of FRP aircraft Instruments panel boards
89 Studies on free vibration of FRP aircraft Instruments panel boards E. Chandrasekaran Professor in Dept. of Civil Engineering, Crescent Engineering College 648 India. e-mail: sekharan@vsnl.net and K.
More informationRevised zone method R-value calculation for precast concrete. sandwich panels containing metal wythe connectors. Byoung-Jun Lee and Stephen Pessiki
Revised zone method R calculation for precast concrete sandwich panels containing metal wythe connectors Byoung-Jun Lee and Stephen Pessiki Editor s quick points n Metal wythe connectors are used in a
More informationGround motion and structural vibration reduction using periodic wave bamer as a passive isolation
Ground motion and structural vibration reduction using periodic wave bamer as a passive isolation A. Niousha, M. Motosaka Disaster Control Research Center, Graduate School of Engineering, Tolzoku University,
More informationLIQUID SLOSHING IN FLEXIBLE CONTAINERS, PART 1: TUNING CONTAINER FLEXIBILITY FOR SLOSHING CONTROL
Fifth International Conference on CFD in the Process Industries CSIRO, Melbourne, Australia 13-15 December 26 LIQUID SLOSHING IN FLEXIBLE CONTAINERS, PART 1: TUNING CONTAINER FLEXIBILITY FOR SLOSHING CONTROL
More informationDowel. Design. Performance-Based World of Concrete Official Show Issue. Lift-truck design changes require a new look at joint durability
2007 World of Concrete Official Show Issue January 2007 Performance-Based Dowel Lift-truck design changes require a new look at joint durability Design By Wayne W. Walker and Jerry A. Holland S erviceability
More informationKeywords: Bracing bracket connection, local deformation, selective pallet racks, shear stiffness, spine bracings.
Send Orders for Reprints to reprints@benthamscience.ae The Open Construction and Building Technology Journal, 2015, 9, 1-6 1 Open Access Investigation of Shear Stiffness of Spine Bracing Systems in Selective
More informationA Full 3-D Finite Element Analysis of Group Interaction Effect on Laterally Loaded Piles
Modern Applied Science; Vol. 12, No. 5; 2018 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education A Full 3-D Finite Element Analysis of Group Interaction Effect on Laterally
More informationTIE BEAMS RESTING ON REPLACED SOIL. 1 and 2 Civil Engineering department Faculty of Engineering, Al Azhar University Cairo, Egypt IJSER
1 STRAINING ACTIONS OF FOOTINGS CONNECTED WITH TIE BEAMS RESTING ON REPLACED SOIL Elbatal, S.A.1 & Abo-Alanwar, M.M.2 1 and 2 Civil Engineering department Faculty of Engineering, Al Azhar University Cairo,
More informationCREATING FREE SURFACES ON HARD ROCKS USING ABRASIVE SUSPENSION WATER JET MANIPULATORS
2009 American WJTA Conference and Expo August 18-20, 2009 Houston, Texas Paper CREATING FREE SURFACES ON HARD ROCKS USING ABRASIVE SUSPENSION WATER JET MANIPULATORS Song S. Han Institute of Construction
More informationMaterials Design: Understanding Vibration Isolation Efficiency Curves
Materials Design: Understanding Vibration Isolation Efficiency Curves Understanding how to compare the overabundance of materials designed for vibration management in today s marketplace is challenging.
More informationUniversity Physics (Prof. David Flory) Chapt_17 Monday, November 26, 2007 Page 1
University Physics (Prof. David Flory) Chapt_17 Monday, November 26, 2007 Page 1 Name: Date: 1. A 40-cm long string, with one end clamped and the other free to move transversely, is vibrating in its fundamental
More informationHeat-Mechanics Interaction Behavior of Laminated Rubber Bearings under Large and Cyclic Lateral Deformation
October 2-7, 28, Beijing, China Heat-Mechanics Interaction Behavior of Laminated Rubber Bearings under Large and Cyclic Lateral Deformation E. Takaoka, Y. Takenaka 2, A. Kondo 3, M. Hikita 4 H. Kitamura
More informationGeopier Foundation Company, Inc.
Geopier Foundation Company, Inc. 800.371.7470 www.geopier.com 4_2006 g e o p i e r f o u n d a t i o n c o i n c t e c h n i c a l b u l l e t i n N o. 9 v i b r a t i o n a n d n o i s e l e v e l s Construction
More informationnot to be republished NCERT ALTERNATING CURRENT Chapter Seven MCQ 1
hapter Seven ALTERNATING URRENT MQ 1 7.1 If the rms current in a 50 Hz ac circuit is 5 A, the value of the current 1/300 seconds after its value becomes zero is (a) 5 2 A (b) 5 3/2 A (c) 5/6 A (d) 5/ 2
More informationK L Rakshith, Smitha, International Journal of Advance Research, Ideas and Innovations in Technology.
ISSN: 2454-132X Impact factor: 4.295 (Volume3, Issue4) Available online at www.ijariit.com Effect of Bracings on Multistored RCC Frame Structure under Dynamic Loading Rakshith K L Department of Civil Engineering
More informationComparison of Transmissibility of Non-Metallic Materials For Vibration Isolation
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-issn: 2278-1684,p-ISSN: 2320-334X PP. 57-61 www.iosrjournals.org Comparison of Transmissibility of Non-Metallic Materials For Vibration A.
More informationEFFECT OF SETBACK RATIO ON SEISMIC PERFORMANCE OF RC STRUCTURES
International Research Journal of Engineering and Technology (IRJET) e-issn: - EFFECT OF SETBACK RATIO ON SEISMIC PERFORMANCE OF RC STRUCTURES Shambhavi B. Hiremath, M.E. Raghu and Dr. G. Chidananda Student,
More informationREDUCING THE VIBRATIONS OF AN UNBALANCED ROTARY ENGINE BY ACTIVE FORCE CONTROL. M. Mohebbi 1*, M. Hashemi 1
International Journal of Technology (2016) 1: 141-148 ISSN 2086-9614 IJTech 2016 REDUCING THE VIBRATIONS OF AN UNBALANCED ROTARY ENGINE BY ACTIVE FORCE CONTROL M. Mohebbi 1*, M. Hashemi 1 1 Faculty of
More informationONE-POINT METHOD FOR DETERMINING MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE FOP FOR AASHTO T 272
ONE-POINT METHOD FOR DETERMINING MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE FOP FOR AASHTO T 272 Scope This procedure provides for a rapid determination of the maimum dry density and optimum moisture content
More informationPHYS102 Previous Exam Problems. Sound Waves. If the speed of sound in air is not given in the problem, take it as 343 m/s.
PHYS102 Previous Exam Problems CHAPTER 17 Sound Waves Sound waves Interference of sound waves Intensity & level Resonance in tubes Doppler effect If the speed of sound in air is not given in the problem,
More informationWaves Q1. MockTime.com. (c) speed of propagation = 5 (d) period π/15 Ans: (c)
Waves Q1. (a) v = 5 cm (b) λ = 18 cm (c) a = 0.04 cm (d) f = 50 Hz Q2. The velocity of sound in any gas depends upon [1988] (a) wavelength of sound only (b) density and elasticity of gas (c) intensity
More informationRESEARCH PAPERS FACULTY OF MATERIALS SCIENCE AND TECHNOLOGY IN TRNAVA, SLOVAK UNIVERSITY OF TECHNOLOGY IN BRATISLAVA, 2016 Volume 24, Number 39
RESEARCH PAPERS FACULTY OF MATERIALS SCIENCE AND TECHNOLOGY IN TRNAVA SLOVAK UNIVERSITY OF TECHNOLOGY IN BRATISLAVA 2016 Volume 24, Number 39 APPLICATION OF NUMERICAL SIMULATION FOR THE ANALYSIS OF THE
More informationVibration Monitoring for University Of Louisville Belknap Campus Master Plan Seven Locations
REPORT TO: Mr. Kenneth Dietz University Architect & Director Planning Design & Construction University of Louisville 421 West Cardinal Blvd. Louisville, KY 40208-5456 SUBJECT: Vibration Monitoring For
More informationStandingWaves_P2 [41 marks]
StandingWaves_P2 [41 marks] A loudspeaker emits sound towards the open end of a pipe. The other end is closed. A standing wave is formed in the pipe. The diagram represents the displacement of molecules
More informationPh.D. Preliminary Qualifying Examination. Cover Page. Thermodynamic. January 17, 2013 (Thursday) 9:30 am 12:30 noon Room 2145 Engineering Building
GENERAL INSTRUCTIONS: COLLEGE OF ENGINEERING MECHANICAL ENGINEERING Ph.D. Preliminary Qualifying Examination Cover Page Thermodynamic January 17, 2013 (Thursday) 9:30 am 12:30 noon Room 2145 Engineering
More information22.19 To determine the wavelength, use the fact that the speed of a wave is equal to its wavelength times its frequency
hhh.schaums.22.19_22.28 22.19 To determine the wavelength, use the fact that the speed of a wave is equal to its wavelength times its frequency or speed = waveln gth frequency speed is in m/s, wavelength
More informationOptimizing the Natural Frequencies of Beams via Notch Stamping
Research Journal of Applied Sciences, Engineering and Technology 4(14): 2030-2035, 2012 ISSN: 2040-7467 Maxwell Scientific Organization, 2012 Submitted: December 02, 2011 Accepted: December 26, 2011 Published:
More informationModal Parameter Identification of A Continuous Beam Bridge by Using Grouped Response Measurements
Modal Parameter Identification of A Continuous Beam Bridge by Using Grouped Response Measurements Hasan CEYLAN and Gürsoy TURAN 2 Research and Teaching Assistant, Izmir Institute of Technology, Izmir,
More informationForming and Shoring Product Selector
Forming and Shoring Product Selector Including RedForm LVL and RedForm-I65, I90, and I90H s Lightweight for Fast Installation Resists Bowing, Twisting, and Shrinking Available in Long Lengths Uniform and
More informationIJSRD - International Journal for Scientific Research & Development Vol. 4, Issue 05, 2016 ISSN (online):
IJSRD - International Journal for Scientific Research & Development Vol. 4, Issue 05, 2016 ISSN (online): 2321-0613 Static Analysis of VMC Spindle for Maximum Cutting Force Mahesh M. Ghadage 1 Prof. Anurag
More informationCharacterization and Validation of Acoustic Cavities of Automotive Vehicles
Characterization and Validation of Acoustic Cavities of Automotive Vehicles John G. Cherng and Gang Yin R. B. Bonhard Mark French Mechanical Engineering Department Ford Motor Company Robert Bosch Corporation
More informationDynamic Modeling of Air Cushion Vehicles
Proceedings of IMECE 27 27 ASME International Mechanical Engineering Congress Seattle, Washington, November -5, 27 IMECE 27-4 Dynamic Modeling of Air Cushion Vehicles M Pollack / Applied Physical Sciences
More informationdescribe sound as the transmission of energy via longitudinal pressure waves;
1 Sound-Detailed Study Study Design 2009 2012 Unit 4 Detailed Study: Sound describe sound as the transmission of energy via longitudinal pressure waves; analyse sound using wavelength, frequency and speed
More informationEffect of Tie Beam Dimensions on Vertical and Horizontal Displacement of Isolated Footing
http:// Effect of Tie Beam Dimensions on Vertical and Horizontal Displacement of Isolated Footing El-samny, M.K. (1), Ezz-Eldeen, H.A. (1), Elbatal, S.A. (1) and Kamar,A.M. (2) (1) Al-Azhar University,
More informationBearing Capacity of Strip Footings on Two-layer Clay Soil by Finite Element Method
Bearing Capacity of Strip Footings on Two-layer Clay Soil by Finite Element Method Ming Zhu Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor Abstract: Parametric study
More informationEPS Allowable Stress Calculations (Rev. 2)
EPS - LDS Calculations - Brigham City Page 1 EPS Allowable Stress Calculations (Rev. 2) 8:11 AM Required Calculate the vertical stress in the top of the EPS block from the live loads (traffic load) for
More informationMODEL MODIFICATION OF WIRA CENTER MEMBER BAR
MODEL MODIFICATION OF WIRA CENTER MEMBER BAR F.R.M. Romlay & M.S.M. Sani Faculty of Mechanical Engineering Kolej Universiti Kejuruteraan & Teknologi Malaysia (KUKTEM), Karung Berkunci 12 25000 Kuantan
More informationHelical Pier Frequently Asked Questions
Helical Pier Basics Q: What is a Helical Pier? A: A helical pier or pile is an extendable deep foundation system with helical bearing plates welded to a central steel shaft. Load is transferred from the
More informationEffect of Masonry Infills on Seismic Performance of RC Frame Buildings
Effect of Masonry Infills on Seismic Performance of RC Frame Buildings Dev Raj Paudel 1, Santosh Kumar Adhikari 2 P.G. Student, Department of Civil Engineering, Andhra University, Visakhapatnam, Andhra
More informationPractical Machinery Vibration Analysis and Predictive Maintenance
Practical Machinery Vibration Analysis and Predictive Maintenance By Steve Mackay Dean of Engineering Engineering Institute of Technology EIT Micro-Course Series Every two weeks we present a 35 to 45 minute
More informationAnalytical and Experimental Investigation of a Tuned Undamped Dynamic Vibration Absorber in Torsion
, June 30 - July 2, 200, London, U.K. Analytical and Experimental Investigation of a Tuned Undamped Dynamic Vibration Absorber in Torsion Prof. H.D. Desai, Prof. Nikunj Patel Abstract subject of mechanical
More informationMode-based Frequency Response Function and Steady State Dynamics in LS-DYNA
11 th International LS-DYNA Users Conference Simulation (3) Mode-based Frequency Response Function and Steady State Dynamics in LS-DYNA Yun Huang 1, Bor-Tsuen Wang 2 1 Livermore Software Technology Corporation
More informationAdvanced Ground Investigation Techniques to Help Limit Risk or Examine Failure. Advanced Subsurface Investigations
Advanced Ground Investigation Techniques to Help Limit Risk or Examine Failure Overview Introduction What is geophysics? Why use it? Common Methods Seismic Ground Radar Electrical Case Studies Conclusion
More informationEffect of temperature on modal characteristics of steel-concrete composite bridges: Field testing
4th International Conference on Structural Health Monitoring on Intelligent Infrastructure (SHMII-4) 2009 Abstract of Paper No: XXX Effect of temperature on modal characteristics of steel-concrete composite
More informationNALYSIS OF STABILIZING SLOPES USING VERTICAL PILES
NALYSIS OF STABILIZING SLOPES USING VERTICAL PILES Mahmoud S. Abdelbaki: Lecturer, Gehan E. Abdelrahman: Lecturer, Youssef G. Youssef :Assis.Lecturer, Civil Eng. Dep., Faculty of Eng., Cairo University,
More informationSVENSK STANDARD SS :2014
SVENSK STANDARD SS 728000-1:2014 Fastställd/Approved: 2014-06-30 Publicerad/Published: 2014-07-01 Utgåva/Edition: 1 Språk/Language: engelska/english ICS: 25.040.20 Spindlar för verktygsmaskiner Utvärdering
More informationElectromagnetic Induction - A
Electromagnetic Induction - A APPARATUS 1. Two 225-turn coils 2. Table Galvanometer 3. Rheostat 4. Iron and aluminum rods 5. Large circular loop mounted on board 6. AC ammeter 7. Variac 8. Search coil
More informationPressure Response of a Pneumatic System
Pressure Response of a Pneumatic System by Richard A., PhD rick.beier@okstate.edu Mechanical Engineering Technology Department Oklahoma State University, Stillwater Abstract This paper describes an instructive
More informationAvailable online at ScienceDirect. Procedia Engineering 125 (2015 )
Available online at www.sciencedirect.com ScienceDirect Procedia Engineering 125 (2015 ) 363 367 The 5th International Conference of Euro Asia Civil Engineering Forum (EACEF-5) Analysis of piled raft foundation
More informationThe Role of Buildings and Slabs-on-Grade in the Suppression of Low-Amplitude Ambient Ground Vibrations
The Role of Buildings and Slabs-on-Grade in the Suppression of Low-Amplitude Ambient Ground Vibrations Hal Amick, Tao Xu, and Michael Gendreau Colin Gordon & Associates, San Bruno, California USA of 5
More informationCHAPTER 11 TEST REVIEW -- MARKSCHEME
AP PHYSICS Name: Period: Date: 50 Multiple Choice 45 Single Response 5 Multi-Response Free Response 3 Short Free Response 2 Long Free Response MULTIPLE CHOICE DEVIL PHYSICS BADDEST CLASS ON CAMPUS AP EXAM
More informationDepartment of Physics United States Naval Academy. Lecture 39: Sound Waves
Department of Physics United States Naval Academy Lecture 39: Sound Waves Sound Waves: Sound waves are longitudinal mechanical waves that can travel through solids, liquids, or gases. The speed v of a
More informationSloshing of Liquid in Partially Filled Container An Experimental Study
Sloshing of Liquid in Partially Filled Container An Experimental Study P. Pal Department of Civil Engineering, MNNIT Allahabad, India. E-mail: prpal2k@gmail.com Abstract This paper deals with the experimental
More informationVibration Analysis on Rotating Shaft using MATLAB
IJSTE - International Journal of Science Technology & Engineering Volume 3 Issue 06 December 2016 ISSN (online): 2349-784X Vibration Analysis on Rotating Shaft using MATLAB K. Gopinath S. Periyasamy PG
More informationResonance and damping characteristics of cryogenic fusion targets
Resonance and damping characteristics of cryogenic fusion targets Harvest Zhang Brighton High School Rochester, NY Advisor: Mr. L. D. Lund Laboratory for Laser Energetics University of Rochester Rochester,
More informationReview of Foundation Vibrations
Review of Foundation Vibrations Philosophy Recall that our objective is to determine the characteristics (i.e. displacement, natural frequency, etc.) of the machine-foundation system shown below. There
More informationNatural Frequencies and Resonance
Natural Frequencies and Resonance A description and applications of natural frequencies and resonance commonly found in industrial applications Beaumont Vibration Institute Annual Seminar Beaumont, TX
More informationTECH SHEET PEM - REF / TESTING CLINCH PERFORMANCE. SUBJECT: Testing clinch performance of self-clinching fasteners.
PEM - REF / TESTING CLINCH PERFORMANCE SUBJECT: Testing clinch performance of self-clinching fasteners. A self-clinching fastener s performance can be divided into two major types. The first is self-clinching
More informationNonlinear behavior of Reinforced Concrete Infilled Frames using ATENA 2D
Available online at www.ijacskros.com Indian Journal of Advances in Chemical Science S1 (2016) 173-178 Nonlinear behavior of Reinforced Concrete Infilled Frames using ATENA 2D M. D. Raghavendra Prasad,
More informationINTERNATIONAL STANDARD
INTERNATIONAL STANDARD ISO 2954 Second edition 2012-04-01 Mechanical vibration of rotating and reciprocating machinery Requirements for instruments for measuring vibration severity Vibrations mécaniques
More informationSHAKER TABLE SEISMIC TESTING OF EQUIPMENT USING HISTORICAL STRONG MOTION DATA SCALED TO SATISFY A SHOCK RESPONSE SPECTRUM
SHAKER TABLE SEISMIC TESTING OF EQUIPMENT USING HISTORICAL STRONG MOTION DATA SCALED TO SATISFY A SHOCK RESPONSE SPECTRUM By Tom Irvine Email: tomirvine@aol.com May 6, 29. The purpose of this paper is
More informationTrigonometric Equations
Chapter Three Trigonometric Equations Solving Simple Trigonometric Equations Algebraically Solving Complicated Trigonometric Equations Algebraically Graphs of Sine and Cosine Functions Solving Trigonometric
More informationSTABILITY. SECURITY. INTEGRITY.
MODEL 150 HELICAL ANCHOR SYSTEM PN #MBHAT STABILITY. SECURITY. INTEGRITY. 150 Helical Anchor System About Foundation Supportworks is a network of the most experienced and knowledgeable foundation repair
More informationMaterial Parameter Measurement (MPM)
Material Parameter Measurement (MPM) C4 Software Module and Accessory of the KLIPPEL ANALYZER SYSTEM (Document Revision 1.3) FEATURES Measure E modulus and damping Evaluate raw materials Specify loudspeaker
More informationV8 Vibration Test Systems
V8 V8 Vibration Test Systems V8-440 Shaker system: configuration and performance parameters V8-440 Metric American Armature diameter 440 mm 17.3 in Sine force peak (stabilised) 57,827 N 13,000 lbf Sine
More informationVIBRATION ANALYSIS AND MODAL IDENTIFICATION OF A CIRCULAR CABLE-STAYED FOOTBRIDGE
VIBRATION ANALYSIS AND MODAL IDENTIFICATION OF A CIRCULAR CABLE-STAYED FOOTBRIDGE Carlos Rebelo, Dep. of Civil Engineering, University of Coimbra Portugal Eduardo Júlio Dep. of Civil Engineering, University
More information