Civil Engineering Reference
In-Depth Information
Figure 3.13
A Junttan hydraulic hammer driving steel piles. (Photograph courtesy of Junttan Oy.)
Approximate drop hammer and single-acting hammer sizes to drive various sizes
of piles based on the design load of the pile are listed in Table 3.6 with the typical
characteristics of selected BSP hydraulic hammers given in Table 3.7.
3.3.2 Pile driving by diesel hammer
Early experiments in driving by the explosive energy of gunpowder are related in
Chapter 1. The modern equivalent is the use of the diesel hammer to produce rapid,
controlled explosions. In operation, the diesel hammer employs a ram that is raised
by explosion at the base of a closed cylinder. Alternatively, in double-acting diesel
hammer, a vacuum is created in a separate annular chamber as the rammoves upward.
This assists in the return of the ram, almost doubling the output rate of the hammer
over the single-acting type. The ram weight is less than that of a drop hammer, but
