Basic Assumptions 4.Constitutive laws f o。=f1-(1-6)] 0 o。=fc 80≤8≤Em 0 O=E,88≤8y 0=f)8>6,y o,=E,6 土水工程学院 得 1010 10 4. Constitutive laws c c cu n c c f f  e e e e e e e  =   = − −  0 0 0 [1 (1 ) ] σ ε0 εu fc y y s y f E  e e  e e e =  =  s es s=Eses e y esu fy Basic Assumptions