ABSTRACT
When speaking about spatial structure geometry, it is common to suggest a surface that passes through the middle of any section of the shell (Figure 2.1.1a). Let’s defi ne specifi c features of a spatial structure. To obtain spatial behavior of a structure, subjected to external loads (the present book is focused on vertical loads), the structure should satisfy the following special requirements:
a) The structure should be continuous to allow the internal forces stream without disturbance from point to point in all directions, not just in that of external loads. The structure can have openings, in this case there are certain constructive requirements (see Section 2.1.3). Ribs or local increase in the structure’s thickness do not break the structure’s continuity, in spite that they lead to local stresses in connections between the structure and the ribs or/and in the zones with varied thicknesses, because the local stresses decrease very fast.
