Consulting engineer, Bethlehem Steel Corporation, Bethlehem, Pa.
Pages: 18 Published: Jan 1979
Field conditions to which steel piles are exposed during installation and service, along with strain measurements made during driving, are presented. The mechanical properties of the steel in the pile butt after driving were determined to see if impact of the ram affected the steel. A review of existing data on the strength of mild steels subjected to high strain rates showed that, in the range of strain rates imposed by impact drivers, the steel yield strength varies from 1.4 to 1.7 times the specification yield strength. The relationship between the specified steel strength and that of a fullsize specimen was reviewed. It is concluded that (a) the driving stress may vary from 1.4 times the yield strength to the ultimate strength of the steel, (b) creep phenomena do not affect mild steels at ground temperatures, and (c) the strength of rolled specimens may be determined using specification strength.
steel piles, driving stress, mill acceptance tests, creep, corrosion
Paper ID: STP33734S