The main concrete pressure is perpendicular to the sealing surface. We split that main vector into two vectors – one vertical and one horizontal. The vertical component is the MALI Effect. We call the horizontal vector – AYA Load.

The AYA Load is a massive force with huge effect on the pile and the ground.

If the offset of the sealing surface is 100 mm.
And if the pile diameter is 600 mm.
And if the concrete pressure is 1 bar Than the AYA Load will be 0.5 ton!!!

In most cases the offset is greater then 100 mm. so the AYA Load is even higher.

The AYA Load pushes the auger toward the wall of the pile. When the operator lifts the auger, because of the AYA Load, the auger scratches and scrapes the wall of the pile. That scratch damages the ground, reduces the corrugated effect and dramatically increases the tension in the lifting cable.

The magnitude of the AYA Load depends on four parameters:
    1. The shape of the auger
    2. The characteristics of the ground
    3. The concrete’s pressure at the bottom of the auger
    4. The rotation of the auger

There is limited knowledge regarding the influence of the shape of the auger on the AYA Load. For the time being, the design of the auger is done according to structural and functional aspects only.

The characteristics of the ground can not be change. We have to adapt our self. As previously said – for the time being we do not know how to do it.
As the concrete’s pressure at the bottom of the auger is lower, the AYA Load is reduced. That is one more reason for keeping the pressure at the bottom of the auger as low as possible.

We can reduce the AYA Load dramatically by rotating the auger during the casting phase. The rotary motion, first of all, rotates the AYA Load among the horizontal plane and spreads the scratches radiantly.

Most of the times, the rotation movement leads to lateral pressure compensation that reduces the asymmetric which creates the AYA Load. The sealing surface becomes closer to horizontal.

Every one can easily see how the rotation of the auger, while casting, reduces the AYA Load.
Try to follow the load in the main lifting cable (simply by tracing the hydraulic pressure at the main dram’s motor) while casting with out auger rotation.
After a while, start to rotate the auger. You will see a dramatic reduction in the hydraulic pressure. The load becomes smaller as the AYA Load is reduced by the rotary movement.

AYA Load is a new insight regarding the mutual relationships between the auger and the ground during the casting phase. For the time being, the best way to reduce the AYA Load is by slowly rotating the auger (drilling wise) while casting.