ULTIMATE BEARING CAPACITY SUPERVISION

Menu qult allows the verification of the ultimate bearing capacity of a rectangular base according to the equations that have been given by Terzaghi, Meyerhof in Hansen (Cernica; 1995), and Vesic (Bowles; 1996). Verification according to all the authors is predefined, but each method can also be switched off (Figure 1).

The package yields six values for the ultimate bearing capacity - Terzaghi has namely given two solutions and there are two slightly different solutions also for the Hansen's theory. The first Terzaghi solution covers square bases and the second one strip bases. As both extreme cases are not very frequent in the engineering practice it can be considered that the actual solution lies between both boundary values. For the Hansen theory for rectangular base also two theories can be found (Šuklje, 1984 and Cernica, 1995). The two theories yield practically identical results except if the terrain around the base is sloped.

The package compares the load of the given base with all six computed values and in case that a computed value is smaller than the load of the base the computed value becomes a red background.

The module further performs the slip control of the base if the transverse load (concentrated load with eccentricity and uniform load) and inplane concentrated load are given.

Figure 1: The input data form for the ultimate bearing capacity computation

The module also allows analysis on a multilayered soil. The form requires the data about all layers (thickness, unit weight, cohesion and internal friction angle for each layer). The module afterwards calculates the average values of the cohesion and the angle of internal friction and implements these values in the analysis with a single layer (Figure 2).

Figure 2: The input data form for the ultimate bearing capacity computation on a multilayered soil

In the report of the ultimate bearing capacity analysis that is created with the WinWord text editor a figure (legend) which allows the graphical representation of the input data is included. In the report, besides results also all equations can be included.

Sample report of the ultimate bearing capacity computation (in Slovene)