## 1. Non-Structural Mass Test

The test checks the non-structural mass feature of B2000++. Free vibration modes of a simply supported plate 1.5 by 1 m and with a thickness of 0.01 m are computed with a given density only or with a part of the mass due to the density moved to the non-structural mass. Both cases must be exactly equal. Values can be consulted in the test file __init__.py.