Three h piles were impact driven in a medium dense sand deposit, load tested in compression, and then extracted. The same three piles were then vibro-driven at a different location and load tested in compression. The top load-top movement curves show that the vibro-driven piles have, on the average, the same ultimate capacity as the hammer-driven piles. These curves also show that at half the ultimateload, the movement of the vibro-driven piles is 2.5 Times larger than the movement of the hammer-driven piles, on average. At half the ultimate load, however, the movement of the vibro-driven piles was only 0.25 In. Some of the piles were instrumented; this allowed researchers to obtain the load transfer curves. These curves showed that the vibro-driven piles carry much more load in friction and much less load in point resistance than the hammer-driven piles. This paper appears in transportation research record no. 1277, Modern geotechnical methods: instrumentation and vibratory hammers 1990.
Abstract