Studies on stress-strain equation of noncohesive soils obtained from oedometer tests based on hypoplastic constitutive model

According to the hypoplastic constitutive model,the stress-strain equation of granular materials could be obtained from oedometer test.The determination of granulate hardness hs and exponent n in a hypoplastic constitutive model was investigated,and a hypoplastic constitutive model was presented based on hypoplasticity.According to hypoplasticity and optimization,the authors put forward an improved method to determine the parameters of n and hs using iterative operation.The further investigation of the equation showed that it could be used to determine stress-strain relation in oedometer test.