Approximation for Terzaghi's Bearing Capacity

Using the general shear failure criterion, the ultimate bearing capacity of a shallow footing was expressed by Terzaghi in terms of bearing capacity factors N c N q , N y . These factors depend only on the soil friction angle, ∖a/, and are usually presented in graphical form. By means of an empirical approximation for each of these factors, a relatively simple equation is developed whereby the ultimate bearing capacity of a shallow footing can be determined directly without recourse to supplementary graphs.