H-Pile Heave: A Field Test

A field test was conducted to investigate the possibility of reduction in pile capacity and the potential for excessive settlements resulting from the heave of H-piles. The piles were driven through relatively softer strata to be seated into an interbedded very dense/hard deposit. A group of 38 pi(es, arranged in an 8x5 cluster, were driven as part of this test. Six previously driven piles, located outside the cluster at distances of 17 ft to 37 ft (5.2 m to 11.3 m), and two previously driven piles located within the cluster were also monitored for heave. The maximum pile heave within the cluster was 1.04 in. (26.4 mm), while 75% of the piles experienced heave between 0.4 and 0.7 in. (10.2 mm and 17.8 mm). Incremental pile heave decreases exponentially with increasing distance from the driven piles. The radius of influence of pile heave was estimated to be approximately 50 ft (15.2 m). Pile load tests showed that pile heave up to 1.04 in. (26.4 mm) had no effect on pile load capacity or on pile load deflection characteristics. Pile tip heave was only slightly less than pile butt heave.