Title page for ETD etd-11242009-020021

Type of Document Master's Thesis
Author Andruet, Raul Horacio
URN etd-11242009-020021
Title Behavior of a cracked shaft during passage through a critical speed
Degree Master of Science
Department Civil Engineering
Advisory Committee
Advisor Name Title
Plaut, Raymond H. Committee Chair
Holzer, Siegfried M. Committee Member
Rojiani, Kamal B. Committee Member
  • Cranks and crankshafts
Date of Defense 1991-08-15
Availability restricted

The detection of cracks in structural components and the evaluation of their sizes without the need of removing them from the machine in which they are placed is very important for preventing failures. The objective of this thesis is to study the effects of cracks on the dynamic behavior of shafts under acceleration or deceleration, in order to find methods or procedures capable of detecting the presence of cracks prior to failure.

The equations of motion for a simply supported Bernoulli-Euler shaft are developed following Wauer's formulation. Galerkin's Method is used to obtain five-term approximate solutions. The first two natural frequencies are found for both the uncracked and cracked shaft. A computer program is written to perform the numerical integration of the equations. The shaft is subjected to several constant accelerations and decelerations. Tables and figures showing the results are presented along with discussions and comments related to the different runs made and the results obtained. The effect of the initial position angle of the eccentricity is studied to find the influence of this parameter. The effects of crack position and crack depth on the dynamic behavior of the shaft are also included in this work. Time histories and summary graphs are presented to make easier the interpretation of the results.

Final conclusions and future research proposals complete the work done in this thesis.

  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
[VT] LD5655.V855_1991.A647.pdf 2.70 Mb 00:12:30 00:06:26 00:05:37 00:02:48 00:00:14
[BTD] next to an author's name indicates that all files or directories associated with their ETD are accessible from the Virginia Tech campus network only.

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.