Practical field methods of pile installation: Which of the following are commonly used to drive piles on site?

Introduction / Context:
Pile foundations transfer loads to deeper strata where surface soils are weak. Installing piles requires imparting energy to overcome soil resistance and achieve required set or depth. Multiple hammer types are used depending on site conditions and pile type.

Given Data / Assumptions:

• Common pile materials: timber, steel, concrete.
• Objective: penetrate soil to design depth with acceptable driving resistance and minimal damage.
• Driving equipment must match pile and soil.

Concept / Approach:
Drop hammers are simple gravity hammers; diesel hammers are self-contained combustion devices providing high blows per minute; single-acting steam (or air) hammers use pressurized working fluid to lift the ram and let it fall under gravity. All are established methods for driving displacement piles.

Step-by-Step Solution:
Select hammer type based on pile capacity, soil resistance, and noise/vibration limits.Monitor set per blow and ensure integrity (e.g., through PDA or dynamic formula checks).Stop when criteria (depth, set, or capacity) are met.

Verification / Alternative check:
Dynamic formulae or wave equation analyses relate hammer energy and set to capacity; load tests confirm capacity post-installation.

Why Other Options Are Wrong:
Each single hammer listed is a valid method; hence the composite choice “All the above” is the correct answer.

Common Pitfalls:
Using an overly aggressive hammer causing pile damage; inadequate cushioning; not accounting for setup/relaxation effects in certain soils.

Final Answer:
All the above.