The Offered Directions in Development and Perfection of Protective Structures and Buildings

The Welded All-Metal "Sandwich Plates" as Elements of Protection Structures By Valeriy S. Kogan, Ph .D. (Eng.) Below are offered for elaboration and introduction the welded all-metal "sandwich plates" as enclosure elements of protection structures subjected to action of concentrated and distributed shock loads. The patentable idea of such structural elements proposed by Valeriy S. Kogan has no analogs in world practice. 1. The "sandwich plates" consist of two "facings" – flat metal sheets (outer and inner), and of joining them shear- stiff "core" – a regular cellular structure of various configuration made of special roll-formed thin-walled metal profiles produced in a waste-free technology. There is possible, to damp out a share of dynamic loads by means of including discrete absorbing parts into the "core" system. 2. The elements of plates (sheets and profiles) are manufactured from special high-strength and heat-proof steels or titanium alloys. The "facings" and the "core" are joined together by the electric or laser spot welding, in necessary cases – in combination with heat-resistant glues. 3. The "sandwich panels" offered may be conditionally divided into following three groups depending on expected (design) shock loads and on spaces between main load-bearing elements of the protection structure. The plates of these three groups differ by the "core" structure, manufacturing technology and economic effectiveness. 4. Group 1 – the plates of 1 15/16" - 3 7/8" (50 100 mm) overall thickness, acting under load as flexible plates or plates of finite stiffness. Their load bearing capacity is limited by their spaces and by using in the "core" structure only limited (small height) range of roll-formed profiles. 5. Group 2 – the plates of 3 7/8" - 9 11/16" (100 250 mm) overall thickness, acting under load as plates of finite stiffness, or as stiff plates. Their load bearing capacity may be sufficiently increased in comparison with the group 1, when using an extended range of roll-formed profiles for the "core" structure ensuring the increased security of their connections. 6. Group 3 – the plates of 9 11/16" - 19 5/8" (250 500 mm) and more overall thickness, acting under load as stiff plates. Under condition of using the special roll-formed profiles for the "core" structure, the stiffness and load capacity of this plates may be increased practically without limitations. It’s especially necessary to note, that groups 2 and 3 cover also a special kind of designs under the conditional name "trampoline". These plates, due to elasticity of a "core" as though "spring" under shock loads, extinguishing thus a significant part of dynamic loadings and raising thus reliability of offered protection.