Analysis of resistance to punching shear of beamless reinforced concrete floor slabs

The analysis of analytical calculation methods provided in various design codes shows that the main factors influencing the punching shear strength of the column-floor slab's combination are estimated differently. Therefore, various calculation methodologies present different empirical coefficients. Calculation methodologies propose different methods for the estimation of the bending moment. Some methodologies estimate the bending moment only partly, whereas others do not estimate it at all. Due to the number of factors, the difference between various calculation methodologies may differ up to 1,59 times, whereas the difference between the results of theoretical calculations and test research, may vary from 1,19 to 2,06 times. Moreover, none of the calculation methodologies completely estimates the singularities of the shear reinforcement, as well as its allocation character and type. Besides, different types of concrete have different resistance to shear. The article explains the main factors that have the greatest influence on the punching shear strength.