# Yield-line Analysis of Two Way Reinforced Concrete Slabs with Openings

*The paper uses yield-line theory to derive equations and charts suitable for the limit design of uniformly loaded rectangular reinforced concrete slabs with rectangular openings. Four positions of openings are considered: the slab centre, the slab corner, the centre of a short side, and the centre of a long side. The ratios of the corresponding lengths of the sides of the opening and the slab are kept the same and sizes of opening of up fo 0.6 of the length of the slab sides are considered. The edges of the slab are assumed to be either all fixed or all simply supported. Design charts are plotted for various values of the ratio of negative to positive yield moments and for the ratio of the yield moments in the two directions.
S. Islam and R. Park
Two-way reinforced concrete slabs often contain*