Piling
 

Introduction:

The uses of piling in sites having poor access or low headroom or on soft ground requires innovative solutions.  Coffey has the technology, the capability, the experience and the know how to deal with these issues.  The technology is the combination vibrator and hammer piling system that permits the driving of sheet piles, H piles and circular piles together with an excavator capability. Throughout Ireland, on bridges and other structures the results of this technology are evident.

Technical Information:

Excavator mounted vibrators are changing the way in which sheet piles have been traditionally driven. Side grip vibrators enable sheet piles to be lifted from the ground, pitched and driven without the need for a crane, piling gates or in some cases a banksman, making this piling system far more cost effective than the traditional method.  The vibrators are powered by the excavators on board hydraulics.  The unique automatic steering system ensures precise pile alignment with the cab mounted display keeping the operator continually informed pile verticality.  The side grip is ideal for low headroom situations.  It is also an excellent pile excavator.  When the quick hitch is used it is possible to change from sheet piler to bucket in just a few minutes.

Plant Description:

The Piling unit is mounted onto the excavator unit and the unit is attached to the machines hydraulic unit which power the vibrators hammers in the unit. The unit is unique in that it can side grip to lift and carry the pile. Once the sheet pile is in the correct position the movax unit can vibrate the pile into the ground using the side grip. Once the pile is driven so far the movax side grip lets go and the movax unit now moves to the top of the pile and drives it to set. The operator carries out the functions from within the cab of the excavator.


Movax Unit & 35 ton Excavator

The advantage of the Movax units is

  • Longer piles Movax can drive longer piles than any other excavator mountable piles  up to 12 - 13 meters.
  • Ability to work under obstacles SP 20-80 can drive 2,5 - 3,5 m longer piles under any obstacles, i.e. bridges, cables on the railway, inside factories, etc.
  • Excellent performance A good operator can in suitable ground conditions:
    • Drive 80-100 piles a day or
    • Extract > 200 piles a day.

The excavator mountable Side-Grip Sheet Piler has the following technical qualities:

  • 30° hydraulic tilting.
  •  ± 360° hydraulic swinging.
  • 3 pairs of jaw (chuck) arms (our patented side-grip) Angle-meter inside the cabin.
  • Full automatic steering.
  • 20-80 ton vibration force.

Coffeys Experience:

Level Crossing Replacement Project OB221F Fanning’s, Templemore - As part of this project steel bearing H piles were required as part of the bridge foundation construction. Initially it was envisaged that a piling rig with drop hammer would be mobilised to site to carryout the piling works under a T3 night possession. This however was not to be the case as an internal strike in Irish Rail between lookouts and management put a halt to the works.
Coffey Construction Ltd proposed to the project team leaders an alternative method of piling which could be carried out by CCL’s specialist plant consisting of the Movax vibratory hammer which could be done without lookout supervision. The reason that CCL’s proposed method could be carried out during the day without lookout supervision was that unlike a piling rig the movax is not top heavy and there is no risk of it toppling over onto the live railway line. The Movax also has powerful gripping jaws, which clamp the pile tightly when working which also reduces the risk of piles toppling out on the railway line. Coffey’s 385 Hitachi with 80 ton Movax was mobilised to site and commenced the piling works.

After all the pile driving was completed CCL employed Lloyd acoustics who carried out all the Dynamic and Static Load testing of the piles (See pictures and test results in the Appendices). The results obtained on these piles met with the specified requirements set out in the contract documents.

Attymon Station Platform Extension (Athenry to Dublin Main Line) - Geotech Specialists Ltd were employed by CCL to undertake a ground investigation at Attymon. The ground investigation confirmed the presence of 3 - 4.5m of peat overlying limestone rock.
CCL submitted a method statement for the proposed method of piling which Iarnrod Eireann accepted. The work had to take place at night due to the frequency of trains passing the station during the day. 5 Nr tower lights were used to provide adequate lighting for the works. A 385 Hitachi with 80 ton Movax was used to drive the H piles. The Movax grabbed the H piles with the gripping jaws and drove the piles as far as possible into the ground. The piles were kept plumb by stopping the Movax at regular intervals and checking the plumbness of the pile with a spirit level. If the piles were not plumb the movax would adjust them to the correct position before commencing the commencing driving again.
CCL took records of all the piling activities. After the piling was complete CCL employed Lloyd Acoustics who carried out the Dynamic pile tests. The results obtained from theses tests met with the requirements for the contract.

Watergate Bridge, Trim – the movax unit was used to drive the piles for the abutment base and temporary sheet piles for the new steel bridge in Trim. A 35 ton excavator with a 80 ton movax drove the pile for the bridge on both sides of the river.

Wicklow Port Access Road, Wicklow – the movax unit was used to drive the piles for the abutment base and temporary sheet piles for the new steel bridge in Trim. A 35 ton excavator with a 80 ton movax drove the pile for the bridge on both sides of the river.

  • The Movax has carried out various Temporary Piling jobs around the country


 

Coffey Group, Athenry, Co. Galway, Ireland Tel: +353 91 844356 Fax: +353 91 844519 Email: info@coffeygroup.com