Analysis and design two way slabs supported on four sides with openings

Abstract

Sometimes it is necessary to provide openings in slabs so that service lines like electrical fittings, water pipes, air conditioning conduits etc. can be taken through them. Slabs with openings are very common in industrial structures such as Mill buildings.It can be stated that Solid slab is one of the most important structural newlinecomponent of a building. Johansen3 has taken up the limit analysis of solid slab using yield line method. Johansen3 has analysed most of the isotropic slabs and presented a simple affinity theorem to solve orthogonal slabs. Subsequently many researchers 1,4,5,6,7,11,18,19,21,22,23 have used the stepped yield line criteria proposed by Johansen to solve different orthogonal solid slabs. Analysis of simply supported isotropic slab with central opening is presented first time by Zaslavsky5. He has presented some design charts also. Later, Islam. S. and Park, R8., have presented orthogonal as well as isotropic slabs supported on simple and continuous edges with different openings at different positions. They8 too have presented some design charts. However, experimental work on slabs with openings is scant. Basing on Zaslavsky s5 work, M. Barik20 has conducted tests on twelve scale models of simply supported isotropic slabs and reported the ultimate load comparisons (with respect to predicted theoretical loads) and governing failure mode. Study of orthogonal slabs with corner opening has not been paid much attention in the earlier days. Harinatha B. Goli and K.Rambabu25 had given the simplified approach to design the orthotropic slabs. Sudhakar K.J. and H.B.Goli27,28 newlineearlier had presented a paper on limit state coefficients for trapezoidal shaped slabs supported on four sides and three sides. K. Rambabu and H.B.Goli29 had given the simplified approach to design orthogonal slabs using affine theorem. ii Available literature so far on the theoretical and experimental work on this area is limited. Hence, A study on orthogonal slabs with corner opening has been chosen in this thesis work.