ABSTRACT
The mechanism of resistance of the mobilized ultimate resistance of a pile is complex. We know that the resistance of a pile can reach its ultimate value with the displacement of 10% of the pile diameter, and that the side and base resistances do not increase in proportion to the load at the pile top up to the ultimate value. Side resistance reaches its ultimate value at a displacement of just under 5% of the pile diameter whereas the base resistance continues to increase at more than 10%. Taking account of this behavior, there may be a relationship between the peak of the side resistance and yield point of a load Po-displacement So curve at the pile top. The relationship has not been well understood because there have been few in situ loading tests with fully mobilized side resistance and indefinite yield point of the curve, so we tried to quantify the relationship by using reliability theory.
