Soma Grand is a 22-Story condominium project on 1160 Mission Street in San Francisco, California with 246 units. We installed 489 Torque Down^® Piles ranging between 55 and 75 feet in length.

Project Conditions

Subsurface conditions varied across the site. The site is generally underlain by fill, Dune sand, peat deposits, and alluvial deposits which vary between stiff clay and dense sand. Piles were extended into the dense sand alluvial deposits to gain support in both friction and end bearing.

Test Pile Program

Ten pile load tests were performed at the site. The plot presented at the right is of two tests performed on the same pile approximately one month apart. An increase of about 200 kips in ultimate capacity was observed following pile set-up.

Production Piles

489 production piles were installed to a depth of between 55 and 75 feet below existing grades. Pile length was determined based on observations made during installation. The length of the Torque Down 1275 pile can be modified in the field by either splicing on additional length or cutting piles which meet early refusal.