1.本程序为平面变形问题非线性有限元程序,可用于计算土坝、地基、挡土墙或地下结构的应力和变形。

2.土的非线性应力--应变关系采用邓肯双曲线模式

另一个弹性常数可有两种选择:

(a)切线泊松比:

(b)切线体积模量:

3.解题方法为中点增量法,考虑到每级加荷的两次计算所得的弹性常数对某些单元可能相差较大,而实际可能处于这两者之间,因此取两者的某种加权平均值作为修正的计算弹性常数,其中初始弹性常数取权为1/4,中点弹性常数取权为3/4,以反映平均结果接近中点弹性常数。

4.网格为任意四边形等参数单元。

5.程序中包含了一维的Goodman接触单元。

6.蓄水引起的湿化,由干、湿两种状态下不同的非线性参数进行计算。

7.可模拟施工过程逐级加荷。

8.坐标方向:y坐标以向上为正,x坐标以向下游为正。

-1. This procedure for the plane deformation of non-linear finite element program can be used to calculate the earth dam, foundation, retaining walls or underground structure, stress and deformation.

2. Soil non-linear stress- strain relationship with Duncan hyperbolic model

The other elastic constants have two options:

(a) tangent Poisson s ratio:

(b) tangent bulk modulus:

3. Problem-solving approach the midpoint of incremental method, taking into account each of the two-stage loading calculated elastic constants for some units may vary widely, but the actual may be in between, so take two a weighted average calculation of elastic constants, as amended, including the right to take the initial elastic constants of 1/4, the midpoint of the right of elastic constants obtained for the 3/4, to reflect the average of the results of close to the midpoint of elastic constants.

4. Quadrilateral grid parameters such as arbitrary units.

5. The program contains one-dimensional contact eleme