LAUSR

Frequently, construction requirements demand to provide service pipelines passing laterally within slab thickness near the slab-column connections of flat slabs. The flat slabs including such conducted pipelines are expected to undergo a significant reduction in the punching shear capacity. For this purpose, experimental program was conducted in this study incorporating 10 specimens of reinforced concrete flat slab. One slab specimen was solid slab with no pipeline as a reference specimen and the other nine slab specimens were fabricated with either single or double pipelines passing through the slab thickness at different locations. Test results indicated that including pipelines within the slab thickness at a horizontal distance equal to or less than one-half of the slab thickness from the face of the column led to a substantial reduction in the ultimate load and the stiffness of the flat slabs. It was also found that the structural performance of a flat slab with double small pipelines horizontally aligned near tension face was more desirable than that of a flat slab with a single large pipeline. Furthermore, a modification is suggested to be introduced to the punching shear equation of Eurocode 2 to include the effect of the embedded pipelines in flat slabs.