请问邓肯张模型初使模量

ansys2007

请问邓肯张模型初使模量的取值一般是怎么样确定的呢？？？？比如说分层加高土石坝，那么每个加高层的肯张模型初使模量E0该怎么取啊？？谢谢大家了


还有就是公式中的西格马3是指围压还是指最小主应力呢？

geo2007

The initial modulus E_0 can be calculated through the formula E_0 = 2*G_0*(1+mu), where mu is the Poisson's ratio, the initial shear modulus G_0 can be determined by in-situ tests, laboratory tests, and empirical relations. In-situ tests include the cross-hole test, the seismic cone penetration test, and the surface wave test, etc. In laboratory, the resonant column test and bender element test are commonly used. In most tests, shear wave velocity needs to be measured to find the G_0 value by using the formula, G_0 = ρ * v_s, where ρ is the mass density and v_s is the measured shear wave velocity.

There are many empirical relations for determining the initial shear modulus. The general expression is given as G_0 = c_g * F(e) * p^n_g * pa^(1-n_g), where c_g and n_g are material constants, e is the void ratio reflecting the compactness of soil, F is a function of void ratio, p is the mean stress, and pa is the atmospheric pressure for normalization. The formula proposed by Hardin and Black (1968) is one of the widely used empirical relations given by G_0 = c_g * (e_g - e)^2/(1+e) * p^n_g * pa^(1-n_g), where e_g is also material constant.

sigma_3 is the minor principal principal stress.