Punching Shear in Reinforced Concrete Flat Slabs in Multi-Storey Car Park Building Structure

Punching shear failure had been the cause of some fatal accidents that had occurred in the past in flat slabs of car park structure. A number of such failure reports had identified the underlying reasons being in the use of outdated or obsolete standards which have been phased out. Therefore, the design and analysis of punching shear strength in reinforced concrete flat slab is a key procedure that requires precision and accuracy. Over the years, although researchers had done a lot of experimental studies on the behaviour of flat slab structures, but the punching shear failures still happened despite many precautions being taken when designing for the car park structure. In this paper, some data that had been presented by previous researchers are used to identify the few design criteria for multi storey car park structure, and these results will also be compared with Eurocode 2 and two other standards, namely the phased out BS8110 and ACI318. From there the analysis for punching shear in multi storey car park structure is carried out using the Eurocode 2 approach considering the varying design parameters such as the sizes of column, slab thickness, span between columns and shapes of column. These parameters played a major role in assessing the punching shear strength in multi storey car park structure. In the model simulation, it was found that among the four selected parameters for study, the thickness of slab and the column size adopted are key factors that can enhance the punching shear strength capacity. On the other hand, the use of square column was proven to have an average of 27% higher punching shear strength than circular column. Besides that, the span between columns in two plane directions are best to range around 6m and 7m but due to car park functional expectations, a flat slab bay area of 8m × 6m and 9m × 6m can be recommended for the purposes of accommodating more car park spaces.