3Duncan, J.M. and Chang, C.Y. Nonlinear analysis of stress and strain in soils[J]. Journal of the Soil Mechanics and Foundations Division, ASCE, 1970, 96( SM5 ) : 1629 - 1654.
4Duncan, J. M., Byrne, P., Wong, K. S., and Mabry, P.Strength. Stress -Strain and Bulk Modulus Parameters for Finite Element Analyses of Stresses and Movements in Soil Masses[R].Report No. UBC/GT/80 -01. Department of Civil Engineering,University of California, Berkeley, California, 1980.
