Cordinate System

( x , y , z ) or

----right hand tria

Displacement (u , v , w ) or

Stress = Linear , stress vector (force / area)

T Stress vector = Force / Area with outward drawn normal

Similarly for other plane

Infinite plane exist at a point P Infinite vectors

Plane/ Area is defined by outward drawn normal.
Infinite planes 3 – mutually outward drawn planes at point P

(x1, x2 , x3,) Planes at P

Stress vector

State of stress at a point

State of stress at a point =


Body is continuous and remain continuous under the action of external forces -

(H1) Elastic Continuum Neighbor remain neighbor under external force No cracks /gaps or voids
(H2) There exists a unique unstressed state of the solid body to which the body returns whenever all the external forces are removed.
(H3) Principle of super position holds good