Example 4.3.1

Given: Consider the double shear bolted connection at right. The upper and lower plates have thickness of a = 10 mm. The middle plate has thickness b = 15 mm. The bolt has diameter d = 10 mm. The system is subjected to a load of P = 5.0 kN as shown at right.

Req'd:
(a) The Maximum Average Bearing Stress in the bolt.
(b) The Average Shear Stress in the bolt.

Sol'n: In order to determine the Average Bearing Stress in the bolt, treat the bolt as a Free-Body Diagram. From the FBD, the Average Bearing Stresses on the top and bottom surfaces of the bolt are:

sB,top =

P/2 ad

=

2.5 kN (10 mm)(10 mm)

= 25 MPa

Similarly, the Average Bearing Stresses on the middle surface of the bolt is:

sB,mid =

P bd

=

5.0 kN (15 mm)(10 mm)

= 33 MPa

Therefore, the Maximum Average Bearing Stress in the bolt is:

In order to determine the Average Shear Stress in the bolt, again treat the bolt as a Free-Body Diagram. Due to the symmetry of the connection, only the top (or bottom) section of the bolt need be analyzed. From the FBD, the Average Shear Stresses in the bolt is:

tS =

P/2 pd2/4

=

2.5 kN p(10 mm)2/4