00771072

Component

https://doi.org/10.3141/1663-03

http://scholar.google.com...rmar&publication_year=1999

The Cooper Marl is a massive geological group, consisting of stiff, cohesive calcareous soils, which serves as the bearing stratum for the large majority of deep foundations in the Charleston, South Carolina, area. It has long been recognized that piles driven into the material experience tremendous setup, or capacity gain with time. Numerous driven piles that bear within the Cooper Marl have been statically or dynamically tested at various times after installation. This pile-testing database has been used to backcalculate the coefficients of a logarithmic expression (Q/Q sub 0 - 1 = Alogt/t sub 0) that predicts pile capacity gain with time. For the largest data set, composed of 305-mm (12-in.) prestressed concrete (PSC) piles, the calculated coefficients are fairly similar, which seems to support the viability of the method and use of the equation. By using the calculated coefficients, long-term pile capacity of 305-mm (12-in.) PSC piles driven into the Cooper Marl should be able to be predicted based on the results of short-term restrike or load test data. The data also indicate that the coefficients of the expression are dependent on the pile size and that the rate of the capacity gain with time generally decreases as the pile size increases.

This paper appears in Transportation Research Record No. 1663, Pile Setup, Pile Load Tests, and Sheet Piles.

English

p. 16-24

1999

Transportation Research Record

0309070597

Figures (7) ; References (9) ; Tables (2)

Backcalculation; Bearing capacity; Calcareous soils; Coefficients; Databases; Load tests; Marl; Mathematical prediction; Pile foundations; Prestressed concrete; Time

Pile setup

Charleston (South Carolina)

Data and Information Technology; Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB

Oct 1 1999 12:00AM

• FINITE ELEMENT-BASED SEEPAGE DESIGN CHARTS FOR SHEET PILES PENETRATING HETEROGENEOUS MEDIA
• MEASURED PILE SETUP DURING LOAD TESTING AND PRODUCTION PILING: I-15 CORRIDOR RECONSTRUCTION PROJECT IN SALT LAKE CITY, UTAH
• MEASURED TIME EFFECTS FOR AXIAL CAPACITY OF DRIVEN PILING
• NORTH CAROLINA DEPARTMENT OF TRANSPORTATION EXPERIENCE WITH PREDESIGN LOAD TESTING
• NUMERICAL PROCEDURE FOR PREDICTING PILE CAPACITY--SETUP/FREEZE
• PREDICTION OF PILE SETUP IN CLAY
• TENSION PILES IN SAND: A METHOD INCLUDING DEGRADATION OF SHAFT FRICTION DURING PILE DRIVING
• VALUE OF METHODS FOR PREDICTING AXIAL PILE CAPACITY