Hydraulically jacked-in pile system is a method of installing pile foundation by means of pushing a pile into the ground.
The penetration pressure required to install a pile into lower layer (stiff clay) can be predicted as 65% of the average of penetration pressure calculated from CPT (Figure 4b)
It can be observed from Figure 5a that the penetration pressure recorded from the jacked-in machine to install 500 mm diameter pile into 5 m thick of expansive clay is larger than that calculated from CPT.
- The penetration pressure required to install the pile into very soft clay layer is independent of pile diameter since the displaced volume of clay 'flows' outward, which does not form unstable mud layer around the pile.
- The penetration pressure required to install the pile into soft to stiff clay layers depends on the pile diameter.
To solve the abovementioned problems, the PC pile with improved soil surrounds, produced by inserting a PC pile into
a DCM column before the initial setting of cement-improved soil (Figure 1), has recently been proposed [1, 2].
It divides the foundation pile into
several elastic units.
It takes nine times to press the whole 170 mm long model pile into
This model takes the heat capacity of the pile into account, and it has made clear progress from the classical line source or "hollow" cylindrical source models.
As shown in Figure 3, the spiral heat source model is further developed here with increasing accuracy and sophistication to take the three-dimensional geometrical characteristic of the spiral pile into account and to describe the actual heat transfer process of the novel pile GHE.
In order to take the effects of heat flow through the top and bottom ends of the pile into account and investigate the long-term operation performance of the pile GHE, a finite spiral heat source model is also established.
As time goes on, a remarkable discrepancy of the finite model from the infinite one appears, since the former takes the heat transfer through the top and bottom ends of the pile into account.
In the lab, and later in field tests, Roy Butterfield and his graduate students demonstrated that by making a metal pile into
a cathode, they could cut by two-thirds the effort needed to drive the pile into
Subdividing the pile into
N sections, the length of each section is h = l/N, as shown in Figure 4.