Abstract
The influence of re-entrant corners on the distribution of bending moments in a flat slab structure is the subject matter of this thesis. Two groups of problems have been investigated. Typical of the first group being a slab supported on columns placed at the intersections of two regular grids and incorporating in the central panel a rectangular hole which varied in size. The second group being that of slabs of rectangular configurations although not quite so regularly supported and each having a rectangular cut-out in one of the peripheral panels. The method of Finite Element has been employed to obtain the theoretical results. A method has been presented which enables one to modify the basis element stiffness matrix such that multi-valued stresses at a re-entrant corner can be faithfully represented. A series of tests on models has been carried out on the Moire Apparatus to determine the bending moments. Although various loading conditions have been tested, it has not been possible due to the volume of work to reduce the results but for the uniformly loaded cases. Good agreement between the experimental and the theoretical results indicates that the analysis yields realistic results. The results are not directly comparable with the Code of Practice C.P.114 values, however, on the basis of the code's recommendation for the values in a slab disturbed by the presence of a halo, a set of values has been calculated and compare with the experimental and the theoretical values. Conclusions have been drawn regarding the overall behaviour of the slabs and the importance of the position of the re-entrant corner on the distribution of the bending moments.