Problem $4.$

The $162225-mm$ rubber blocks shown are used in a

double$-$U shear mount to isolate the vibration of a machine

from its supports. An applied load of $P=690N$ causes the

upper frame to be deflected downward by $7$ mm $.$

a$.$ Determine the shear modulus, $G,$ of the rubber

blocks.

b$.$ Calculate shear strain in each corner of the front face

of the block $($dimensions $16mm22mm).$

c$.$ Draw a $3$D stress element showing all normal and

shear stresses.

d$.$ Write out two $33$ matrixes, one for stress and the

other for strain, in the rubber blocks after load $P$ is

applied.

Shear deformation

of blocks