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Titan II Missile Silo, Launch Control Room The control room is mounted underground via huge isolation springs. A typical spring is shown in the background. The purpose is to isolate the control room from mechanical shock and vibration in the event of a nuclear strike above the launch site. The springs allow 18 inches of relative displacement. The control room could thus carry out a retaliatory strike, as order by the U.S. president. This site is located south of Tucson, Arizona. It has been decommissioned and is now a museum.

Tutorials  Damping Damping Properties of Materials: damping.pdf This tutorial gives the loss factors for aluminum, steel, copper, and other engineering materials. Damping Cross-Reference: dcross.pdf Recommendations for Revision of Seismic Damping Values in Regulatory Guide 1.61: seismic_damping.pdf Damping Mechanisms for Microgravity Vibration Isolation: mvi.pdf The Half Power Bandwidth Method for Damping Calculation: half_power_bandwidth.pdf Damping Loss Factors for Damping Materials for Continuous Structures: DampLF.pdf By P. H. Mathuria and U.P. Kulkarni Kijewski and Kareem, Analysis of full-scale data from a tall building in Boston: damping estimates: boston.pdf NASA, Measurement of Damping of Composite Materials for Turbomachinery Applications: tm207685.pdf Free Vibration with Coloumb Damping (Dry Friction Damping) : coloumb.pdf H. Cole, On-Line Failure Detection and Damping Measurement of Aerospace Structures by Random Decrement Signatures, NASA CR-2205 nasa_cr2205_1.doc nasa_cr2205_2.doc nasa_cr2205_3.doc Alternate: cr2205.pdf C. Johnson, Design and Application of Vibration Suppression: vibration_suppression_banner.pdf Hubert & Swanson, Surface Tension Lockup in the IMAGE Nutation Damper - Anomaly and Recovery: 2001_hubert_swanson.pdf Tuned Mass & Liquid Dampers Structures Incorporating Tuned Mass Dampers: TMD_Table.pdf Tuned Liquid Damper: TLD_chapter1.pdf TLD_chapter5.pdf TLD_chapter2.pdf TLD_chapter6.pdf TLD_chapter3.pdf TLD_chapter7.pdf TLD_chapter4.pdf TLD_chapter8.pdf Isolation Avionics Isolation Design Guidelines: avionics_iso.pdf Vibration Analysis of an Isolated Mass with Six-degrees-of-freedom: six_dof_isolated.p Vibration Analysis of an Isolated Mass with Three-degrees-of-freedom. This includes a method for vertically offset isolators: isolators_threedof.pdf Notes on Shock Testing of Isolated Avionics Components: isolator_test_notes.pdf Notes on Finite Element Modeling of Isolated Components: FE_isolated.pdf Two-Stage Isolation for Harmonic Base Excitation: two_stage_isolation.pdf Matlab script: two_dof_frf.m Machine Mounting for Vibrattion Attenuation:  machine.pdf J.S. Lamancusa, Vibration Isolation: vibiso12.pdf P. Masterson, The Basics of Vibration Isolation Using Elastomeric Materials: vib_iso.pdf Vibration Absorbers Livanos, Raffan, and Coltrona, Active Control of Vibration in Tall Buildings VibrationTallBuildings.pdf Wheel and Rail Vibration Absorber Testing and Demonstration: wheel.pdf Software Description Executable Source Damping value cross-reference includes loss factor, reverberation time, and other parameters. damping.exe - EAR Grommets, B-434/R-444, B-435/R-445 EAR.exe EAR.cpp  This program performs a curve-fit on an acceleration spectral function resulting from an applied force. The main purpose is to determine the damping ratio. The spectral function may be: 1. acceleration PSD 2. acceleration Fourier magnitude 3. transfer function magnitude (accel/force)    bandwidth_damp.exe   bandwidth_damp.cpp Calculate relative displacement from absolute acceleration and vice versa. relative_displacement.exe relative_displacement.cpp Calculate isolator static deflection or quasi-static deflection due to rigid-body acceleration. isolator_static_deflection.exe isolator_static_deflection.cpp