ABSTRACT
This chapter distinguishes internally geometrically stable, unstable, and instantaneously unstable systems by number and placement of connection. Attached systems are distinguished as externally geometrically stable, unstable, and instantaneously unstable systems. Stable systems are separated into statically determinate – systems with required constraints only, and statically indeterminate – systems with redundant constraints. Geometrically stable attached bar systems are termed as framed structures. Framed structures are separated into thrusted and thrustless by the direction of their support reactions to vertical loading. In thrustless structures, vertical loading produces vertical support reactions only, whereas in thrusted structures vertical loading produces oblique reactions. Bar systems can be completed by cables and cable subsystems. The designing of complicated technical objects includes two stages: the stage of developing the object’s structure and preliminary evaluation of its technical characteristics, and the stage of verification and adjustment of original engineering solutions.
