Foundation footings: a) types of concrete benches, b) types of reinforced concrete benches, c) asymmetrical bench used by the neighbor's building, d) symmetrical reinforced concrete bench.
Concrete footings are made with the cross-sections shown in the drawing. The width of the bench b = a + 2s should be taken as such, that in the concrete of the footing at its bottom no tensile stresses greater than the allowable stresses Rbz for the adopted concrete class. The haunched sections are used instead of the rectangular section, mainly for savings reasons. The height of the bench at the ends of the haunch should not be less than 15 cm.
The width of the bench at the base of the basement wall should be greater than the wall thickness by two offsets. This facilitates the correct location of the wall in the plan in the case of, if there were some deviations in dimensions when making the benches. The width of the shoulder is assumed to be within 5-10 cm.
Reinforced concrete benches can be made of much larger widths, in order to transfer high loads to soil with low bearing capacity. Dimensions of reinforced concrete benches (width and height) is adopted according to the rules for dimensioning reinforced concrete and the conditions of load-bearing capacity and use, i.e.. bearing capacity of the foundation structure, soil bearing capacity, foundation subsidence, the inclination of the building in the event of uneven settlement.