| This paper estimates the reliability of the ultimate bearing capacity of shallow foundations and grouped-pile foundations. First, model uncertainty in the estimation for the bearing capacity of shallow foundations is evaluated using small and large-scale plate-load test results and design formulas. A similar evaluation is then conducted for single piles using in-situ load test results, and furthermore, the reliability of a pile group as a system is estimated considering the increase in the reliability with increase in the number of piles, because most pile foundations in Japan are grouped-pile foundations with more than 5 piles. Finally, this paper shows that the reliability indices for shallow foundations and grouped-pile foundations with more than 4 piles that are designed following current design specifications are equivalent. |
