Does Caesar predict soil failure (exceedance of soil bearing resistance) at buried bends or are additional calculations required? From what I can tell, it calculates the yield load (fy) from the input soil properties and if it is exceeded the stiffness goes from the high K1 value to the very low K2 value (i.e. soil fails). Does Caesar use the Rankin Passive Pressure equation to calculate this yield load? If not, how is fy calculated