Pile Foundation Engineering involves the design, installation, and load-bearing assessment of piles used to support structures on unstable soil or water. The 1935-miami-dade-building-code provides detailed specifications for various pile types, ensuring structural integrity through specific material standards and load testing protocols.
Wood Piles
Wood piles must be Dade County pine or approved wood, free from decay and driven green. Specific dimensional requirements include a minimum diameter of 6 inches at the point and 10–12 inches at the butt, depending on length (p. 220). Creosoted piles (Douglas fir or Southern pine) may be used above ground water level if treated to specific retention standards and capped with concrete (p. 220-221). The allowable load for wood piles is determined by formulas involving hammer weight and penetration, capped at 20 tons for untreated and 15 tons for creosoted piles (p. 221).
Concrete Piles
Concrete piles must comply with material standards for Portland cement and reinforcement. Allowable working stress is limited to 12% of the ultimate compressive strength, except for piles cast in steel tubes, which allow higher stresses (p. 221-222). Pre-cast piles require specific longitudinal reinforcing and hooping, with length limitations based on diameter (p. 222).
Steel Piles
Rolled structural steel piles must meet structural steel quality requirements and have a minimum metal thickness of 3/8 inch. Allowable loads are determined by similar formulas as wood piles or via load tests (p. 222).
Load Testing
The Building Inspector may require load tests to determine safe bearing power. Test piles must sustain twice the design load for 48 hours with minimal settlement (p. 222). This process is critical for validating structural-load-calculations and ensuring the safety of foundations in variable soil conditions.