Installation of steel H- piles

Installation of Steel H-piles
Step 1 --- Installation Procedures
a-Set out the steel pile location correctly on site.
b-Excavate about 3-4 m at pile location to remove shallow obstruction and then backfill, whenever necessary.
c-Set up the diesel hammer/drop hammer in conjunction with a pile driver.
d-Erect and install the bottom section of steel pile required size into the ground by driving with the diesel hammer/drop hammer.
e-Extend the pile by welding on additional section during driving.
f-Verticality of the pile section will be monitored by means of spirit level from time to time.
g-Continue the above procedure until the pile has been driven to final set according to the Final h-Set Table in the piling plans.
A follower will be used, when necessary, to drive the pile into the ground for final set where the cut-off level is deep.
i-At a particular pile position, where deep boulder obstructions are encountered during pile driving, extract the steel pile and drive a steel tubular pile down to punch through obstructions or use a 'Down-The-Hole' hammer to predrill through the boulder layer before the reinstallation of steel H-pile.
Step 2 --- Relationship Between H-pile & Concrete Pile
In order to ascertain the adequacy of the driven concrete pile, a dynamic formula, Hiley's Formula, will be applied to access the safe loading capacity of the pile.

Step 3 --- Monitoring Proposal
In order to ensure no adverse effects imposed on the adjoining buildings and structure during construction, the following precautionary measures and limiting criteria, to be monitored throughout the construction period, are recommended :
a-Settlement checkpoints and other monitoring devices are to be installed prior to the commencement of construction works.
b-Initial monitoring results should be submitted to the Governmental Department prior to the commencement of works.
c-The checkpoints and standpipe piezometers shall be monitored regularly during the construction period and duplicate copies of the monitoring results should be submitted to the Governmental Department on a regular basis and be kept available on site for inspection at all times.
d-Should the settlement at those checkpoints be found excessive during the course of works, the works should be suspended and the A.P., the Governmental Department should be notified immediately. Remedial proposal to safeguard the affected structure shall be submitted to the Engineer for approval.
e-Drawdown of water table in standpipes should not be greater than the specific value during the course of work.
f-All Monitoring devices should be maintained in good order during the works.
Step 4 --- Method Statement for Passing through Bouldery Obstructions During Pile Driving
a-In order to ensure no adverse effects imposed on the adjoining buildings and structure during construction, the following precautionary measures and limiting criteria, to be monitored throughout the construction period, are recommoned :
b-Where shallow boulder obstructions are expected or encountered during pile driving, a backhoe excavator will be used initially to excavate to remove bouldery obstructions about 6-7 m beneath ground surface.
c-At a particular pile position, where bouldery obstructions are encountered during pile driving at a depth beyond the reach of the arm of the backhoe excavator, extract the H-piles and a steel tubular pile ( or a heavier steel H-section ) will be driven down as to punch through the bouldery obstructions before re-installation of the H-pile.
d-Where the punching method cannot practically penetrate through the boulders, withdraw the pile and break the boulder obstructions with 470 dia. 'Down-the-hole' hammer to predrill through the boulder layer before re-installation of the H-piles and backfilled the hole with soil for pile driving.
e-The pile is then pitched and driven to final set according to the final set tables.