3dec软件介绍.doc

2.7 Sign Conventions

The following sign conventions are used in 3DEC and must be kept in mind when entering input

or evaluating results.

BLOCK MOTION — Positive motion is in the positive coordinate axes directions.

DIRECT STRESS— Positive stresses indicate tension; negative stresses indicate compression.

SHEAR STRESS — With reference to Figure 2.17, a positive shear stress points in the positive

direction of the coordinate axis of the second subscript if it acts on a surface with an outward

normal in the positive direction. Conversely, if the outward normal of the surface is in the

negative direction, then the positive shear stress points in the negative direction of the coordinate

示例：施加边界条件、初始条件

应力边界 ：