Hello everyone,

When I output the integration point coordinates of C3D20 element in Abaqus to the .rpt file(Step Time=0, Increment=0), I found that the values of coord.coord1, coord.coord2, and coord.coord3 are not exactly the same as the usual 27 integration point scheme, and there are some accuracy errors.

For example, the coordinates of the first integration point of the abaqus C3D20 element are (-774.596691E-3, -774.596691E-3, -774.596691E-3). However, typically, the integration point coordinates of the 27 integration point scheme are sqrt(0.6), which is approximately equal to 774.5966692E-3(refer to Zienkicwics's book). Can anyone explain the source of this error.