// CODE SNIPPET
1810.7 Caisson Piles
JUMP TO FULL CODE CHAPTER
Caisson piles shall consist of a shaft section of concrete or grout-filled pipe, extending to bedrock, with an uncased socket drilled into bedrock of Class 1c or better and filled with concrete or grout. The caisson pile shall have a full-length structural steel core, full length steel reinforcing, or a stub core or steel reinforcing installed in the rock socket and extending into the pipe portion a distance equal to the socket depth. The minimum outside diameter of the caisson pile shall be 7 inches (194 mm), and the diameter of the rock socket shall be approximately equal to the inside diameter of the pile.
Pipe and steel cores shall conform to the material requirements in Section 1809.3. Pipes shall have a minimum wall thickness of 3/8 inch (9.5 mm) and shall be fitted with a suitable steel-driving shoe or cutting teeth welded to the bottom of the pipe. Concrete or grout shall have a 28-day specified compressive strength (f'c) of not less than 4,000 psi (27.58 MPa).
For the purposes of Section 1810.7, threaded bars conforming to ASTM A 615 and ASTM A 722 shall be considered the same as deformed reinforcing bars.
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.
The gross cross-sectional area of the structural steel core or bundled center reinforcing shall not exceed 30 percent of the gross area of the caisson. For reinforcing placed at the perimeter of the caisson, the area of the reinforcing shall not exceed 8 percent of the area inside the casing. Minimum concrete cover shall be in accordance with Table 1808.2.13.
Steel reinforcing shall be spliced in accordance with the requirements of ACI 318.
The rock socket and pile shall be thoroughly cleaned of foreign materials before filling with concrete or grout. Steel cores shall be set within 6 inches (125 mm) above the base of the rock socket. Concrete shall not be placed through water except where a tremie or other method approved by the commissioner is used.
Caisson rock sockets shall be subject to special inspection in accordance with Section 1704.9. All caisson rock sockets shall be inspected to verify rock quality. Inspection may be accomplished by direct observation, by video methods or by a core boring performed prior to the drilling of the socket.
Related Code Sections
1810.7 Soils and Foundations, Caisson Piles
Caisson piles shall conform to the requirements of Sections 1810.7.1 through 1810.7.7 ...
NYC Building Code 2014 > 18 Soils and Foundations > 1810 Cast-In-Place Concrete Piles > 1810.7 Caisson Piles
1810.7 Soils and Foundations, Caisson Piles
Caisson piles shall conform to the requirements of Sections 1810.7.1 through 1810.7.9 ...
NYC Building Code 2008 > 18 Soils and Foundations > 1810 Cast-In-Place Concrete Pile Foundations > 1810.7 Caisson Piles
§27-713 Foundations, Caisson Piles
(a) Description. Caisson piles shall denote concrete filled pipe piles that are socketed into bedrocks of class 1-65, 2-65 or 3-65 and constructed ...
NYC 1968 Code (Vol I) > 11 Foundations > 10 Pile Types--Specific Requirements > §27-713 Caisson Piles
1808.1 Soils and Foundations, Scope
Deep foundation elements, including but not limited to piles, caisson piles, and helical piles, shall comply with Section 1808. In addition, driven ...
1810.7.7 Soils and Foundations, Rock Socket Inspection
Caisson rock sockets shall be subject to special inspection in accordance with Section 1704.9. All caisson rock sockets shall be inspected to verify ...
NYC Building Code 2014 > 18 Soils and Foundations > 1810 Cast-In-Place Concrete Piles > 1810.7 Caisson Piles > 1810.7.7 Rock Socket Inspection