Berkeley Engineering And Research, Inc.
Plures Intelligens Modicum Machinatorem
Telephone: 510-549-3300 
Fax: 510-962-8230 

BEAR Project Receives Award


BEAR wins Best Paper of the Year

BEAR paper on preventing gasoline can explosions wins Best Paper of the Year


Alcohol Containers Explode Too!



Failure Analysis  

  Theater Seats  |  Aircraft Engine Components  

Theater Seats


Failure analysis of theater seats (shown above left) is typical of the wide variety of assessments performed by BEAR. Each seat back was held in place by two bolts, one on each side, through a small metal tab (shown above right). To determine the loads on the tab when a seat was used by various persons, strain gauges were installed on an actual seat (lower left) and peak loads recorded. Field measured loads were also applied to a computer model of the tab (lower right) to examine peak stresses in the corner of the tab and the fatigue life of the seat. As expected, the tab dimensions were found to be inadequate.


Aircraft Engine Components


The connecting rod shown here was analyzed for stress concentrations in the connecting rod itself and the bolts used to hold it together. BEAR performed a parametric study of bolt pre-loads using finite element analysis to determine the necessary bolt pre-load to reduce stress below critical levels. Our results determined the cause of failure and new pre-load specifications to prevent future failures.