What is the equation for calculating punching shear in a square concrete footing?

The equation for calculating punching shear in a square concrete footing is derived from considerations of shear forces acting on the critical section around the column. The correct formula incorporates parameters such as the strength of the concrete, the dimensions of the footing, and factors related to punching shear resistance.

In this context, the equation V = Φ * 4 * λ * SQRT(F'c) * b0 / d accurately captures these relationships:

• The variable V represents the shear force at the critical section.
• Φ is a strength reduction factor that accounts for variability in material properties and loading conditions.
• λ is a factor that adjusts for the effect of the column dimensions and loading conditions on shear capacity.
• SQRT(F'c) reflects the square root of the concrete compressive strength, which is a crucial factor in determining the shear capacity.
• b0 refers to the perimeter of the critical section around the column, while d represents the effective depth of the footing.

This formula effectively combines all these elements to yield a reliable measure of punching shear capacity. The inclusion of the factor 4 in the equation accounts for the geometry of the critical section, making it specific to square footings. Overall, the equation allows for the assessment of the adequacy of a