1-26.  A cantilever is subject to a vertical random force  as shown in the figure. If the allowable shear strain at point C is , determine the probability of failure. Given that the cantilever has a Shear modulus of  .  and  are independent.

 

 

Solution:

Section Properties

                                                                                                                                                        

                                                                                                                                                                                       

Shear Stress

                                                                                                                      

Shear Strain

                                                                                                                             

Since , we have

                                                                                                                                     

                                                                                                                                      

Set , then , where

     

Thus, the probability of failure of the cantilever could be obtained by

              Ans.