A function for calculating the natural frequencies and mode shapes for an elastic beam supported by end springs is included in: Matlab script: Vibrationdata Signal Analysis Package The function can be accessed via: >> vibrationdata > Miscellaneous > Structural Dynamics > Beam Bending > Beam… Read more
I have added a function for calculating the free vibration response of an SDOF system to initial conditions to the Vibrationdata GUI package. Matlab script: Vibrationdata Signal Analysis Package >> vibrationdata > Miscellaneous > Structural Dynamics > Spring-Mass Systems > SDOF Free Vibration Response to… Read more
A function for calculating cylindrical shell natural frequencies via the wave method is now included in the Vibrationdata GUI package. Matlab script: Vibrationdata Signal Analysis Package This function may be accessed via: vibrationdata > Structural Dynamics > Rings & Cylinders > Cylinder, Wave Model Reference… Read more
I have added a feature for rectangular plate bending modes to the Matlab GUI package. Matlab script: Vibrationdata Signal Analysis Package The script allows for the addition of point masses and point constraints. This is a work-in-progress. The next step will be to add base… Read more
I have added a feature for a two-degree-of-freedom system subjected to an applied force to the Matlab GUI package. The applied force options are steady-state sine, arbitrary time history and PSD. Matlab script: Vibrationdata Signal Analysis Package The new feature can be accessed via: Vibrationdata… Read more
PowerPoint Slides: Webinar_30_rectangular_plates.pptx Audio Visual File: NESC Academy Rectangular Plate Shock & Vibration – Recommend viewing in Firefox with Sliverlight Plugin * * * References: Leissa, Vibration of Plates Plate Base Excitation: plate_base_excitation.pdf The Natural Frequency of a Rectangular Plate Point-Supported at Each Corner: plate_point_corner.pdf * *… Read more
PowerPoint Slides: Webinar_29_stress_velocity.pptx Audio Visual Files: Recommend viewing in Firefox with Sliverlight Plugin NESC Academy Stress-Velocity Relationship Part I NESC Academy Stress-Velocity Relationship Part II * * * Acceleration Time History: Time (sec) & Accel (G) srs1000G_accel.txt * * * References: Stress-Velocity Relationship: sv_velocity.pdf Bending Frequencies of… Read more
PowerPoint Slides: Webinar_28_mdof_SRS.pptx Audio/Visual Files: Recommend viewing in Firefox with Sliverlight Plugin NESC Academy Multi-degree-of-freedom SRS Part I NESC Academy Multi-degree-of-freedom SRS Part II Three-dof System Example: three_dof_srs_revC.pptx * * * Acceleration Time History: Time (sec) & Accel (G) srs2000G_accel.txt * * * References:… Read more
The original Tacoma Narrows Bridge was opened to traffic on July 1, 1940. It was located in Washington State, near Puget Sound. Strong winds caused the bridge to collapse on November 7, 1940. Initially, 35 mile per hour winds excited the bridge’s transverse vibration mode,… Read more
Method 1 Secondary & Component loads can be specified in the form of a Mass-Acceleration curve as described in: NASA-STD-5002, Paragraphs 4.2.1.2, 5.3.2, 5.4. The Mass-Acceleration curve can be derived from measured flight or test data, or analytical loads. Care must be taken to avoid… Read more