Hurricane hugo made landfall in 1989 near charleston, south carolina, causing extensive damage. A pleasure boat marina was exposed to the full force of the storm. The marina consisted of concrete floating docks held in place by 14-in.-Square prestressed concrete piles. The 42-ft-long piles had been driven 2 years before, and installation records were not available at the time of the testing (1990). The water depth was between 2 and 10 ft, and the soil conditions consisted of approximately 10 ft of soft mud overlying the cooper marl. During the storm, the surge floated the docks to nearly the pile topsand the extraordinary winds and waves pushed the large pleasure boats against the piles. After the storm, it was observed that some piles could be moved several inches laterally simply by pushing on themwhile standing on the docks, thereby causing the pile integrity to be questioned. Short on time for the new season, the owner was facedwith a serious problem with potentially expensive remedies. Low-strain integrity testing performed on each of the 78 piles provided a timely and cost-effective solution for pile structural integrity assessment. Testing was performed in 2 days at an average cost of less than $100 per pile. Testing indicated that none of the piles were structurally damaged, although some records showed evidence of tensile cracking and an absence of soil resistance. The pile testing program, as well as the theoretical background and field testing proceduresare discussed. This paper appears in transportation research recordno. 1331, Integrity testing of foundations 1991
Samenvatting