12-02-2016, 04:33 PM
Introduction
Limitations of elastic analysis of slab.Slab panels are square or rectangular.One-way slab panels must be supported along two opposite sides only , the other two edges remain unsupported.Two-way slab panel must be supported along two pairs of opposite sides , supports remaining unyielding.Apply loads must be uniformly distributed.Slab panels must not have large openings.
History
Yield Line Theory as we know it today was pioneered in the 1940s by the Danish engineer and researcher K W Johansen.As early as 1922, the Russian, A Ingerslev presented a paper to the Institution of Structural Engineers in London on the collapse modes of rectangular slabs.Authors such as R H Wood, L L Jones, A Sawczuk and T Jaeger, R Park, K O Kemp, C T Morley, M Kwiecinski and many others, consolidated and extended Johansen’s original work so that now the validity of the theory is well established making Yield Line Theory a formidable international design tool. In the 1960s 70s and 80s a significant amount of theoretical work on the application of Yield Line Theory to slabs and slab-beam structures was carried out around the world and was widely reported.