PARAM, SHL2MEM

Bulk Data Entry A shell property (defined by the PSHELL Bulk Data Entry) is automatically converted into a membrane property if the membrane thickness (field T) of the PSHELL Bulk Data Entry is less than the value specified using PARAM, SHL2MEM.

Parameter Values Description
SHL2MEM <Real Number > 0.0>

No default (See Comment 6)

 A shell property (defined by the PSHELL Bulk Data Entry) is automatically converted into a membrane property if the membrane thickness (field T) of the PSHELL Bulk Data Entry is less than or equal to the value specified using PARAM, SHL2MEM. This is done by setting MID2 and MID3 to blank for the PSHELL.

Comments

  1. With regard to determining the conversion from a PSHELL shell to membrane property, the nodal thicknesses defined using the Ti fields of the CTRIA3/CTRIA6 or the CQUAD4/CQUAD8 Bulk Data Entries are ignored.
  2. If the value of the field T in the referenced PSHELL entry is less than or equal to the value of PARAM, SHL2MEM then the shell property is converted to a membrane property regardless of the Ti field values.
  3. PARAM, SHL2MEM should be used with caution in optimization runs, as this parameter will also apply to design properties. If the shell thickness on such design properties (in PSHELL) is lower than the value specified with PARAM, SHL2MEM, they will automatically be converted to membrane properties (regardless of the value of their corresponding design variables).
  4. If PARAM, SHL2MEM is used in optimization runs where the shell thickness (T) field of the PSHELL entry is blank, then the SHL2MEM parameter is ignored and it has no effect.
  5. PARAM, SHL2MEM is intended for use with 'skin' elements, which are useful for stress calculation on the surface of solid (3D) elements.
  6. Defaults:
    • If PARAM, SHL2MEM is input without specifying a value, the code will error out (no default).
    • If PARAM, SHL2MEM is not used, the conversion from shell property to a membrane property will not occur.
  7. Plasticity is supported with membrane elements (first and second order) for small and large displacement nonlinear static analysis. Among the available hardening rules in the MATS1 entry, isotropic, kinematic and mixed hardening types are supported with membrane elements.