METHOD STATEMENT FOR PILE BREAKING

METHOD STATEMENT FOR PILE BREAKING

1. Mark the correct cutting level using survey instrument and cut along the marking with cutting dish at least 4 centimeter into the core.

                         FIGURE 1. The pile is cut around it's perimeter by dish grinder with a cutting blade.

(Photo taken from Jizan University Project, Jizan, Kingdom of Saudi Arabia)

Remarks:
Notice that the blinding was casted first before cutting the piles. This method is not advisable because the surface of blinding gets damaged during pile breaking. After breaking the piles, the damaged surface of the blinding has to be rectified before placing waterproofing which is a clear case of double work.



2.   Break the pile using large jackhammers up to thirty centimeters above the marked level.

FIGURE 2. About 80% of the length of the pile head is cut down using compressor driven jackhammers.

(Photo taken from Al Rayyan Complex Project, Sharjah, United Arab Emirates, October 2008)

Remarks:
An alternative way of pile breaking is to use the Pile Breaker Machine supplied by Piling Contractors. However, some machine can cut the pile reinforcement during the breaking process that leads to additional work of splicing the reinforcement with couplers.



3.  Break the remaining thirty to forty centimeters of pile head by small electric jackhammers and flatten it to
     the correct level. Chipping of small loose concrete to be done manually by hammer and chisel.

FIGURE 3. Electric powered light jackhammer is used to achieved the proper level and even surface.

(Photo taken from Al Rayyan Complex Project, Sharjah, United Arab Emirates, October 2008)

Remarks:
A heavy jackhammer cannot be used to leveling the final surface because it breaks the pile head in large chunks. Notice from the picture that the surveyor's rod man is checking the level of the inner side. The outer perimeter of the pile is already in the required level which was previously cut by cutting dish.



4.  Finally all pile reinforcement shall be cut to the required development length and all reinforcement with
     insufficient development length shall be spliced with couplers.

FIGURE 4. All completed pile heads are marked with masking tape and the pile number is written on the masking tape for reporting purpose.

(Photo taken from Al Rayyan Complex Project, Sharjah, United Arab Emirates, October 2008)

Remarks:
The soil surface is leveled and compacted after completion of pile cutting in preparation for blinding. Casting the blinding after completion of pile breaking is the more advisable sequence of work as this avoids damage to the surface of blinding.


Prepared by : Engineer Raul C. Yalung
Civil & Construction Engineer

E-mail : raulyalung@yahoo.com