### 3.11.1. Draping Shear

Ply draping on arbitrarily shaped surfaces leads to local shearing of the plies. This manufacturing-induced artifact can lead to significant deviation between the assumed and effective mechanical properties. This is because the shearing can be in the order of several degrees before ply wrinkling becomes an issue. Thus, the configuration of the composite can vary considerably from point to point, as can the mechanical properties.

In order to reflect the mechanical properties’ dependence upon draping shear, ACP-Pre provides a draping simulation tool. Upon specifying shear-dependent material properties in Engineering Data and enabling draping in ACP-Pre for individual plies or Oriented Selection Sets, downstream analysis systems take this effect into account.

The draping shear angle is defined as:

Thus, a shear angle of 0 degrees indicates that the ply at the corresponding location is unsheared. According to the definition, negative shear angles are not possible.

Release 18.2 - © ANSYS, Inc. All rights reserved.