Vertical capacity of piles using fuzzy sets

Because prediction of the load-carrying capacity of piles continues to chal lenge geotechnical engineers, new solutions are needed. The problem is aggr avated by the lack of understanding of the phenomena of soil-pile interacti on, and the limited quantity and inexact quality of subsurface soil informa tion that can be provided for analysis. The use of fuzzy set theory improve s the engineer's ability to handle the uncertainty in the soil parameters a nd the prediction methods and thus improves the reliability of the predicte d capacity. A methodology for predicting pile capacity based on fuzzy set t heory is developed and implemented in a computer program. The validity of t he program results is evaluated using a US Federal Highway Administration ( FHWA) pile load test database. The comparison between predicted and measure d ultimate capacities of piles in sand, clay and mixed soils shows that the predictive capability of the developed program is very good.