Besides compressive strength, other important stresses are also used in designing concrete structure. The stresses, of which we can have an idea from Modified Goodman diagram, are:
In reinforced concrete beam
-flexural compressive strength
-flexural tensile stress
In case unreinforced concrete-flexural tension stress
In case of stated above, the fatigue limit is also 55% of respective strength in static loading. Modified Goodman diagrams are only a general guidance. There have other factors which also influence fatigue strength of concrete like loading rate, age, and moisture condition. The explanation of this diagram with the description of symbols will be published later.