Meyerhof Method (SPT)
This solution for cohesive and cohesionless soils use a Meyerhof theory, where the bearing capacity of foundation soil is given by a formula:
It is recommended to use a safety factor FS = 3 when calculating the bearing capacity using this method.
bearing capacity of foundation soil
average value of SPT blow counts measured at depths from footing base to 1.5*bef bellow the footing base
effective footing width
GWT influence factors
depth of footing bottom
load inclination factor
The formula is derived for imperial units [tsf, ft] - the program calculates automatically in the units used in the program.
In saturated very fine or silty sands, the measured SPT blow count for Ni > 15 should be corrected as follows:
This corellation can be performed automatically in the frame "".
GWT influence factors Cw1 and Cw2 are determined as follows:
hGWT = 0 (water in the terrain level) -> Cw1 = Cw2 = 0.5
hGWT = d (water in the depth of footing bottom) -> Cw1 = 0.5; Cw2 = 1
hGWT > d + 1,5*bef -> Cw1 = Cw2 = 1
depth of ground water table from the terrain
Intermediate values Cw1 and Cw2 are interpolated.
Load inclination factor Ri is interpolated according to the following table:
horizontal component of resultant load
vertical component of resultant load
This method should not be used for ratio H/V > 0.6.
The influence of inclined terrain and inclined footing bottom is considered same way as in.
Bridge Engineering Handbook (Wai-Fah Chen, Lian Duan, 1999)