Database-Based Analysis of Various Interpretation Criteria for Barrette Piles in Drained Soils

An evaluation of various compression interpretation criteria for barrette piles under drained soil conditions was done in this study, together with the comparison of the results with previous researches. In order to achieve the objectives, a total of 18 load test results of barrette piles under drained soil conditions were collected and stored in a database for keen evaluation. These interpreted capacities were analysed by comparing each of the criterion with a set specific interpretation method, thus shedding light on the interrelationships of each interpretation criteria to the set standard. Upon normalizing the interpreted capacities with that of the results of the L₂ method, it was found out that the interpreted values of L₁ is at 48% of the L₂ interpretation and can be utilized for serviceability design with displacements under 7 mm. DeBeer, Terzaghi and Peck, van der Veen, and slope tangent interpretations are all in the transition region of the normalized load-displacement curve with displacements ranging from 17 to 31 mm. Davisson method yielded almost the same mean normalized value as the L₂ interpretation with mean displacements at 43.4 mm. DIN 4026 is recommended for designs under 47 mm mean displacement while Fuller and Hoy and Chin methods are un-conservative methods which always over-estimate the capacity with displacements exceeding 104.8 mm. Finally, specific recommendations to guide the design of barrette piles under drained conditions are provided.

Keywords: Barrette Piles, Foundations, Drained Soils, Interpretation Criteria.