Geotech Info for Helical Piles 1

[Geotech1986]

What "other" information should the geotech engr. of record provide other than ult. / allowable bearing capacity and skin friction values when preparing a geotech report for a Helcial Pier contractor? By the way, the 30-ft. boring info. is summarized as follow:
0 to o.5': Topsoil
.5' to 4.5': Highly Plastic Clay (CH); SPT values ranged from 11 to 27; MC's are within PL.
5' to 18': Moderately Plastic Clay (CL); SPT's ranged from 15 to 30; MC's are within PL.
19' to 30': Moderately Plastic Clay (CL); SPT's ranged from 20 to 32; MC's were generally within PL.

Also, the Active Depth is generally about 15 to 16 feet in this area.

Your assistance is greatly appreciated.
Respectfully,
Geotech1986

 

[PEinc]

You should talk to a A. B. Chance Anchor representative and check out their web site and Helicap program. With the program, you enter the soil layers and sol properties (gamma, phi, cohesion, blow counts) to calculate the ultimate pier or anchor capacity. The Helicap program calculates the bearing at each helix. I had written my own program to calculate the ultimate geotechnical capacity but Helicap also considers the structural capacity of the pier or anchor. To answer your question, all geotech reports should at least give actual tested gamma, phi, and c values for the various soil strata.

http://www.PeirceEngineering.com