The depth of the rock socket in Class 1c rock or better shall be sufficient to develop the full load-bearing capacity of the caisson pile based upon the sum of the allowable bearing pressure on the bottom of the socket in accordance with Table 1804.1 plus an allowable bond stress of 200 psi on the sides of the socket. The depth of the socket in Class 1c rock or better below the bottom of the pipe shall not be less than 3 feet (914 mm) of the outside diameter of the pipe.
Load tests, with instrumentation in the rock socket to demonstrate the transfer of force to the rock, shall be performed to justify the use of bond stresses above 200 psi (1379 kPa). The number of load tests shall be in accordance with the requirements of Section 1808.4.1.1. A report summarizing the methods and results of the load test shall be submitted to the commissioner for approval.