Coefficient of Calculation of Inflection Point
When the classical methods are used the input coefficient kinf allows the determination of the inflection point location based on Linf = L/kinf. In this case, the coefficient kinf represents a very important input parameter strongly influencing the shape and slope of subsidence trough. Its value depends on the average soil or rock, respectively, in overburden - literature offers the values of kinf in the range 2.1 - 4.0.
Based on a series of FEM calculations the following values are recommended:
gravel soil G1-G3
kinf = 3.5
sand and gravel soil S1-S5, G4, G5, rocks R5-R6
kinf = 3.0
fine-grained soil F1-F4
kinf = 2.5
fine-grained soil F5-F8
kinf = 2.1
The coefficient for calculation of inflection point is input in the frame "Settings".