1810.7.3 Bracing at tops of deep foundations.
BC § 1810.7.3
Deep foundations shall be braced to provide lateral stability and resist eccentric loads and moments in all directions. Three or more deep foundations connected by a rigid cap shall be considered braced, provided that the deep foundations are located in radial directions from the centroid of the group not less than 60 degrees (1 rad) apart. A group of two deep foundation elements in a rigid cap shall be considered to be braced along the axis connecting the two deep foundations. Methods used to brace deep foundations shall be subject to the approval of the commissioner. Deep foundations supporting walls shall be driven alternately in lines spaced at least 1 foot (304.8 mm) apart and located symmetrically under the center of gravity of the wall load carried, unless effective measures are taken to provide for eccentricity and moments due to lateral forces, or the deep foundations supporting the wall are adequately braced. A single row of deep foundations without bracing is permitted for one and two-family dwellings and lightweight construction not exceeding two stories or 35 feet (10 668 mm) in height, provided the centers of the deep foundations are located within the width of the wall.
