8 10-1 The Specific Energy of Deformation and Strain Energy of Elastic Body I. The specific energy of deformation Under the complex stress conditions. suppose that the elastic body is imposed all the six components of stress ax,O, O,,Ty,Tzx,Exy According to the principle of conservation of energy, e value of the strain energy has no relation to the sequence of the forces imposed on the elastic body, but is completely decided by the final value of the stress and strain Thus we obtain the strain energy density or specific energy of the elastic body U1=1(0+0,,+0+17+27n+) The specific energy expressed by the components of stress 1(++0)1201+0+0)++=++ 2E 77 §10-1 The Specific Energy of Deformation and Strain Energy of Elastic Body ( ) ( ) ( )( ) 2 2 2 2 2 2 1 2 2 1 2 1 x y z y z z x x y yz z x xy E U =  + + −    +  +  + +   + + The specific energy expressed by the components of stress I. The specific energy of deformation ( ) U x x y y z z yz yz z x z x xy xy =   +  +  +  +  +  2 1 1 Under the complex stress conditions, suppose that the elastic body is imposed all the six components of stress . According to the principle of conservation of energy, the value of the strain energy has no relation to the sequence of the forces imposed on the elastic body,but is completely decided by the final value of the stress and strain. Thus we obtain the strain energy density or specific energy of the elastic body: x y z yz zx xy  ,  , , ,