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D-CAD Technologies Development Centre forApplied Dynamics |
Machine Foundation Design Competency Centre for Frame and Block Foundation Rotary, Reciprocating, Impact Machines and Vibration Isolation |
About the Handbook
Table of Contents
Foreword
Preface
Acknowledgement
CONTENTS
Highlights of 2nd edition ix
About the Handbook xi
Acknowledgement xxv
Foreword xxvii
Preface to 2nd edition xxix
Preface xxxi
Symbols and notations xxxiii
PART - I
THEORY OF VIBRATION
BASIC UNDERSTANDING WITH SPECIFIC APPLICATION
TO
MACHINE FOUNDATION DESIGN
1 UNDERSTANDING DYNAMICS OF MACHINE FOUNDATIONS 1-1 1.1 Industrial Machines 1-4 1.2 Design Philosophy 1-5 1.3 Dynamics of Machine Foundation System 1-9 1.3.1 Natural Frequency 1-10 1.3.2 Excitation Frequency 1-11 1.3.3 Dynamic Force 1-11 1.3.4 Resonance: 1-11 1.4 Tuning of the Foundation 1-13 1.4.1 Frequency Margin 1-13 1.5 Support System 1-14 1.6 Design Parameters 1-15 1.7 Vibration Isolation 1-16 1.8 Field Performance and Feedback 1-16 EXAMPLE PROBLEMS 1-18 [Top]
2 SINGLE DEGREE OF FREEDOM SYSTEM 2-1 2.1 Free Vibration 2-4 2.1.1 Undamped SDOF System 2-4 2.1.2 Damped SDOF System 2-17 2.2 Forced Vibration 2-21 2.2.1 Un-Damped System - Dynamic Force Applied Externally 2-21 2.2.2 Damped System 2-27 2.2.3 Un-Damped System Subjected To Impact Loads 2-34 2.2.4 Un-Damped System Subjected To Impulsive Loads 2-36 EXAMPLE PROBLEMS 2-40 [Top] 3 MULTI- DEGREE OF FREEDOM SYSTEMS 3-1 3.1 Two Degrees of Freedom System - Free Vibration 3-5 3.1.1 Two Spring Mass System- Linear Springs 3-5 3.1.2 A Rigid Block Supported By Vertical and Translational Springs 3-7 3.1.3 A Rigid Block Supported By Vertical and Rotational Springs 3-8 3.1.4 A Rigid Block Supported By Translational and Rotational Springs 3-10 3.1.5 Multiple Spring Mass Systems Connected By a Massless Rigid Bar 3-14 3.1.6 A Portal Frame Supporting Mass at Beam Center 3-17 3.2 Two Degrees of Freedom System - Forced Vibration 3-19 3.2.1 Un-Damped System Subjected To Harmonic Loads 3-19 3.2.2 Un-Damped Two Spring Mass System- Subjected To Impact Load 3-33 3.3 Three Degrees of Freedom System - Free Vibration 3-35 3.3.1 Three Spring Mass System 3-35 3.3.2 A Rigid Block Supported By Vertical, Translational & Rotational Springs 3-36 3.4 Three DOF System - Forced Vibration 3-39 3.4.1 Three Spring Mass System Subjected To Harmonic Excitation 3-39 3.4.2 A Rigid Block Supported By Vertical, Translational & Rotational Springs Subjected To Harmonic Excitation 3-41 3.5 Amplitude at Resonance 3-44 3.5.1 Amplitude at Resonance- Frame Foundations (2 & 3 Spring Mass Systems) 3-44 3.5.2 Amplitude at Resonance for Block Foundation 3-44 EXAMPLE PROBLEMS 3-47 [Top] 4 VIBRATION ISOLATION 4-1 4.1 Principle of Isolation 4-3 4.2 Transmissibility Ratio 4-3 4.3 Isolation Efficiency 4-6 4.4 Isolation Requirements 4-7 4.5 Selection of Isolators 4-9 EXAMPLE PROBLEMS 4-11 [Top]
PART - II
DESIGN PARAMETERS
5 DESIGN SUBGRADE PARAMETERS 5-1 5.1 Introduction 5-3 5.2 Soil Aspects Influencing Soil Structure Interaction 5-3 5.2.1 Energy Transfer Mechanism 5-4 5.2.2 Soil Mass Participation in Vibration of Foundations 5-6 5.2.3 Effect of Embedment of Foundation 5-7 5.2.4 Applicability of Hook's Law to Soil 5-7 5.2.5 Reduction in Permissible Soil Stress 5-8 5.2.6 Damping in Soil 5-8 5.3 Dynamic Soil Parameters 5-9 5.3.1 Dynamic Soil Modulus 5-9 5.3.2 Coefficients of Subgrade Reaction 5-10 5.4 Design Soil Parameters 5-19 5.4.1 Variation With Respect to Static Stress or Overburden Pressure 5-21 5.4.2 Variation With Respect to Base Contact Area of Foundation 5-21 5.5 Equivalent Springs 5-22 5.5.1 Foundation Supported Directly Over Soil 5-22 5.5.2 Foundation Supported Over an Elastic Pad 5-29 5.5.3 Foundation Supported Over a Set of Springs 5-33 5.5.4 Foundation Supported Over Piles 5-36 EXAMPLE PROBLEMS 5-41 [Top] 6 DESIGN MACHINE PARAMETERS 6-1 6.1 Parameters For Rotary Machines 6-4 6.1.1 Dynamic Forces 6-4 6.1.2 Critical Speeds of Rotors 6-11 6.1.3 Aero-Dynamic / Hydro-Dynamic/ Electro-Dynamic Excitations 6-11 6.1.4 Transient Resonance 6-12 6.1.5 Rotor Bearing Supports 6-14 6.1.6 Forces Due To Emergency and Faulted Conditions 6-14 6.1.7 Coupling of Machines 6-15 6.2 Parameters for Reciprocating Machines 6-16 6.2.1 Dynamic Forces for Single Cylinder Machine 6-16 6.2.2 Dynamic Forces for Multi-Cylinder Machine 6-20 6.2.3 Transient Resonance 6-22 6.2.4 Forces Due to Emergency and Faulted Conditions 6-22 6.2.5 Coupling of Machines 6-22 6.3 Parameters for Impact Machines 6-23 6.3.1 Machines Producing Repeated Impacts- Forge Hammers 6-23 6.3.2 Machines Producing Impulse/Pulse Loading 6-28 6.4 Amplitudes of Vibration 6-31 EXAMPLE PROBLEMS 6-32 [Top] 7 DESIGN FOUNDATION PARAMETERS 7-1 7.1 Foundation Type 7-3 7.2 Foundation Material 7-5 7.2.1 Concrete 7-5 7.2.2 Reinforcement 7-7 7.3 Foundation Eccentricity 7-8 7.3.1 Foundation Eccentricity For Block Foundation 7-8 7.3.2 Foundation Eccentricity For Frame Foundation 7-8 7.4 Foundation Tuning 7-9 7.4.1 Under-Tuned Foundation 7-11 7.4.2 Over-Tuned Foundation 7-12 7.5 Other Miscellaneous Effects 7-12 7.6 Vibration Limits In Machine Foundation Design 7-13 7.7 Block Foundation 7-14 7.7.1 Foundation Sizing 7-14 7.7.2 Foundation Stiffness 7-15 7.7.3 Strength Design 7-16 7.7.4 Minimum Reinforcement 7-16 7.8 Frame Foundation 7-17 7.8.1 Foundation Sizing 7-18 7.8.2 Stiffness Parameters For Frame Foundation 7-20 7.8.3 Strength Design 7-23 7.8.4 Minimum Reinforcement 7-23 [Top]
PART - III
FOUNDATIONS FOR REAL LIFE MACHINES
8 MODELING AND ANALYSIS 8-1
8.1 Classical Method (Manual Computational Method) 8-5
8.1.1 Block Foundations 8-5
8.1.2 Frame Foundations 8-6
8.2 Using Commercially Available Analysis Packages 8-7
8.2.1 Computational Packages Based on Structural Analysis Methods 8-7
8.2.2 Computational Packages Using Finite Element Method 8-9
8.2.3 Mathematical Modeling 8-9
8.2.4 Machine 8-9
8.2.5 Foundation 8-10
8.2.6 Soil 8-13
8.2.7 Dynamic Forces 8-20
8.2.8 Boundary Conditions 8-20
8.2.9 Material Data 8-21
8.2.10 Degree of Freedom - Incompatibility: 8-22
8.3 Dynamic Analysis 8-22
8.3.1 Free Vibration Response 8-22
8.3.2 Forced Vibration Response 8-25
8.4 Strength Analysis & Design 8-26
8.4.1 Block Foundations 8-27
8.4.2 Frame Foundations 8-27
EXAMPLE PROBLEMS 8-28
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9 BLOCK FOUNDATIONS FOR ROTARY & RECIPROCATING MACHINES 9-1
9.1 Design of Block Foundation 9-3
9.1.1 Required Input Data 9-3
9.1.2 Loads on Machine Foundation 9-4
9.2 Classical Method (Manual Method of Analysis) 9-5
9.2.1 Sizing of Foundation 9-5
9.2.2 Dynamic Analysis 9-5
9.2.3 Mathematical Representation 9-5
9.2.4 Free Vibration 9-7
9.2.5 Forced Vibration 9-9
9.3 Finite Element Method 9-18
9.3.1 Modeling 9-19
9.3.2 Sizing of Foundation 9-19
9.3.3 Dynamic Analysis 9-20
9.3.4 Strength Analysis and Design 9-20
FOUNDATIONS FOR REAL LIFE MACHINES 9-21
Foundation for Low Speed Machine 9-22
Foundation for a vertical pump motor unit 9-51
Foundation for a Reciprocating Engine 9-76
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10 FRAME FOUNDATIONS FOR ROTARY & RECIPROCATING MACHINES 10-1
10.1 Design of Frame Foundation 10-4
10.1.1 Required Input Data 10-5
10.1.2 Loads on Machine Foundation 10-6
10.2 Classical Method (Manual Method of Analysis) 10-6
10.2.1 Sizing of Foundation 10-6
10.2.2 Dynamic Analysis 10-6
10.2.3 Lateral Vibrations of Frames 10-12
10.2.4 Vertical Mode of Vibration 10-13
10.2.5 Lateral Vibrations Coupled With Torsional Vibrations 10-19
10.2.6 Strength Analysis and Design 10-24
10.3 Finite Element Method of Analysis 10-25
10.3.1 Modeling 10-25
10.3.2 Sizing of Foundation 10-26
10.3.3 Dynamic Analysis 10-27
10.3.4 Strength Analysis and Design 10-28
FOUNDATIONS FOR REAL LIFE MACHINES 10-28
Foundation for Rotary Machine - Turbo Generator Unit 10-29
Foundation for Reciprocating Compressor 10-60
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11 FOUNDATIONS FOR IMPACT & IMPULSIVE LOAD MACHINES 11-1
11.1 Hammer Foundations 11-3
11.1.1 Foundation Sizing 11-5
11.1.2 Dynamic Analysis 11-6
11.2 Foundations for Machines Producing Impulsive Loads 11-11
11.2.1 Foundation Sizing 11-13
11.2.2 Dynamic Analysis 11-13
FOUNDATIONS FOR REAL LIFE MACHINES 11-16
Foundation for Drop Hammer 11-16
Foundations for Machines Producing Impulsive Loads 11-25
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PART - IV
VIBRATION ISOLATION SYSTEM
For REAL LIFE MACHINES
12 VIBRATION ISOLATION SYSTEM 12-1
12.1 Vibration Isolation Design 12-3
12.1.1 Sizing of Inertia Block 12-4
12.1.2 Selection of Isolators 12-4
12.1.3 Location of Isolators 12-4
12.1.4 Dynamic Analysis 12-4
FOUNDATIONS FOR REAL LIFE MACHINES 12-6
Vibration Isolation for a Fan Foundation 12-7
Vibration Isolation of a Crusher Foundation 12-17
Vibration Isolation of Test Bed for Automotive Engines 12-30
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PART - V
FOUNDATIONS FOR R & M PROJECTS
13 R & M PROJECTS (RENOVATION & MODERNIZATION PROJECTS) 13-1
13.1 Evaluation of Dynamic Soil Parameters 13-5
13.1.1 FFT analysis of Vibration Measurements records 13-5
13.2 Isolated Foundations 13-9
13.2.1 Block Foundations 13-9
13.2.2 Frame Foundations 13-9
13.2 Common Foundation Shared By Other Dynamic Machines 13-10
FOUNDATIONS FOR REAL LIFE MACHINES 13-11
Foundation for a Motor Fan Unit of a Captive Power Plant 13-12
Foundation for a Motor-Fan Unit on a Common Raft 13-26
PART - VI
CONSTRUCTION ASPECTS & CASE STUDIES
14 CONSTRUCTION ASPECTS 14-1 14.1 Construction Joints 14-5 14.2 Embedded Parts 14-5 14.3 Placing / Laying of Concrete 14-6 14.4 Grouting 14-7 14.5 Anchor Bolts 14-7 [Top]
15 CASE STUDIES 15-1 15.1 Introduction 15-3 15.2 Case Studies (Field Examples) 15-6 15.2.1 High Vibrations of a Motor Compressor Unit 15-6 15.2.2 210 Mw Turbo-Generator Unit - High Vibration Problems 15-7 15.2.3 Reciprocating Compressor on Isolation Pads 15-11 15.2.4 Vibration Isolation of FD Fan Foundation 15-12 15.2.5 Tilting of Anchor Bolts of a Frame Foundation 15-13 [Top]