Prescription Techniques

ROADBUILDING – Hydraulic Rock Breaker

“Hydraulic Hammer Handles Buttle Bluffs Job”

by

Eric L Kay, Forest Road Consultant

Truck Logger Magazine, January issue, 1999

Case study – Cost-effective low-impact coastal Forest Road construction

Construction of the Buttle Bluffs main in the fall/winter of 1999, located in the Mount Adrian area of central Vancouver Island required a narrow footprint with a minimum of environmental and visual impact. Road running width was kept at a minimum (yet ensuring user safety). To reduce the amount of disturbed ground absolute control of the cut and fill slope angles were desired and these were kept to a minimum as was the variable width right of way clearing.

Conventional drilling and blasting would have required controlled blasting to control fly rock and to control overbreak. Techniques such as pre-shear holes, special explosives and the use of blasting mats would have been needed to ensure control in the blasting process.

End-haul disposal sites were non-existent on the portion of the road constructed thru Strathcona Park and would have involved high trucking costs as the nearest disposal sites were some distance away.

TimberWest chose the use of the hydraulic hammer instead of conventional drilling and blasting for the Hammers ability to break rock without environmental impact.

The 11,000 foot/lb G100 Rammer from Thiessen Equipment was mounted with a quick-change on a Hitachi EX300LC excavator owned by Greg Bergeron of Eureka Excavating Ltd. The Excavator was equipped with the standard Wajax “Roadbuilder full bush guarding package”. Wayne Cooledge of Wajax Equipment of Campbell River says “It was also equipped with an extra 2000lb counterweight to counterbalance the hammer and was especially plumbed to supply a balanced large hydraulic flow to the hammer by our shop crew here in Campbell River” He also stresses that the Wajax quick change (15-20min to change from the hammer to either the dig or clean-up bucket) leaves the excavator truly versatile.

Hydraulic hammer owner Greg Bergeron of Eureka Excavating Ltd states “I really believe in them (the hammer) or I wouldn’t be in the business” and I also comments “(that) the hammer is the way its going to be in the future”. He also feels that “In the future there will be more manufacturers and suppliers of hammers.”

Paul Berg, Superintendent of TimberWest comments “We were looking to save the costs associated with endhauling”. “(The) breaking up of the material to use as ballast and capping and (also) not wasting time going back and drilling rock in the ditchlines was a money saver”

“The road was engineered to use the cut material as balanced cuts and fills, (thereby) reducing lateral movement of material” says Gary Veitch, RPF, Operations Engineer for TimberWest. “The rock was weathered granitic material that stands up well when in place” “The hammer gave us more usable material for ballast and on this particular job gave us better material”. “Personally I like the hammer for the ditchline” says Gary. “The width and shape can be exactly what you want without the possibility of fractured rock from overblasting and the chance of mis-directed water” He also comments, “The hammer gives a nice controlled cutslope without any excess material to be handled and eliminates the problem of disposing (end-hauling) excess material from blasting overbreak”.

“The other hoe (TimberWest’s) with the dig bucket was going ahead and cold-decking logs and pioneering where he could while I was doing ditchline” says Hydraulic Hammer operator, Dave McVey of Campbell River. “When he came to an outcropping of rock and was rocked out we would change places, and he would come back and excavate the material I had broken up in the ditches and he used it to construct finished grade”

Dave took care to make material selectively, larger material for subgrade and fines for capping. The rock “broke well” says Dave. Larger rock was especially made for armouring culvert outlets.

“Up in that particular area it (the hammer) worked out exceptionally well” “It was the size of the hammer as well”, “(it is) very effective”, “the G100 is a very good breaker”

“I was pretty well impressed with it” says TimberWest hoe operator Rob Hobenshield who was working in tandem with the breaker. Rob is also a blaster and comments “There were also lots of large boulders and the breaker dealt quicker with them than by drilling each one and blasting it” He also notes that “we had fallers working close by and blasting would have been limited to twice a day”

“We also did not require a ballast crew”, notes Rob, which would have involved a gravel pit or quarry with excavator for loading, trucks for hauling and a cat for spreading.

TimberWest Bullbucker Steve Telosky notes that the grade was steep in places (27%) with some pretty generous cuts and that there was no rock wasted over the bank and neither was any material trucked in either for ballast or capping eliminating those potential costs.

It has long been known that the hammer has had a place in the past in sensitive or high-risk areas such as under powerlines, near highways, railways, creeks or lakes, or where vibration from blasting would be considered a hazard. TimberWest has not crunched the final numbers yet, but from indications given to this reporter, they appear pleasantly surprised by the apparent economy of the construction and the short construction time of this piece of road.

An added advantage was the cost savings associated with allowing the falling and road construction phases to continue uninterrupted while the hammer was working. In a conventional situation, the road building equipment along with the fallers would have to be moved out for each blast.

Given the apparent success, both environmentally and economically and of the short project completion time, it would be easy to contemplate possible future projects for the Hydraulic Hammer in Coastal Logging Road Construction.

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ADDITIONAL DOCUMENT and CONTACT INFORMATION:

LICENSEE

Paul Berg, Operations Superintendent

Gary Veitch, R.P.F. Operations Engineer

TimberWest, Oyster River Division - 250-287-8161

Road - Buttle Bluffs Main (BB Main)

Area – Mount Adrian/Buttle Lake, Vancouver Island

EQUIPMENT OWNER

Greg Bergeron

Eureka Excavating Ltd.

Box 277, Campbell River, BC - 250 334 3755 or cel 250 203-1177

HAMMER OPERATOR

David McVey – 250 287-9930

Address – Campbell River

HAMMER SUPPLIER

Thiessen Equipment Limited, Noel McAuley - 604 514-8326

Website: www.thiessenteam.com

Email: thiessen@direct.ca

HAMMER MANUFACTURER

Make : Rammer

Model: G100

Breaking force: 11,000 pounds

Working weight, kg 3800

Impact energy according to CIMA method, J 5218

Impact rate, bmp(beats per minute) 350-550

Acceptable oil flow, l/min 220-350

Carrier minimum pressure, bar 205

Hammer operating pressure, bar 155-165

85 dB (A) level distance, m 30-42

Carrier weight limits, tons 40-70

Website: www.rammer.com

EXCAVATOR SUPPLIER

Wajax, Campbell River, Wayne Cooledge - 250 287-7177

Hitachi EX 300 LC – Operating weight 77,000 lb.

Added counterweight – 2,000lb

Full bush guarding, Hydraulic thumb, 2 buckets (Change from hammer to bucket in 15 minutes) High volume flow plumbing for hammer. Tracks cut down to 26” width.

Website: www.wajax.com