RELATION BETWEEN MODULUS OF ELASTICITY AND BULK MODULUS

Suppose a block is subjected by three-dimensional forces P as shown in Figure 12.23.

Figure 12.23 Fluid Pressure and Volumetric Strain of a Cube

Bulk modulus is a ratio of fluid pressure and volumetric strain. It is denoted by K.

Here –ve sign is used for reduction in volume.

Let us consider a cube of unit length is subjected to fluid pressure P. It is clear that the principal stresses are P, − P, and −P and linear strain in each direction is