tunnels and a ten years

7/29/2019 tunnels and a ten years

1/6

4

MINING &CONSTRUCTION

TUNNELSAND A TEN-YEAR

The Atlas Copco Rocket Boomer WL3 C drill

rig (above and top right) at work on the Torres

Finale road scheme in Sicily.

SPO

TLIGHT

ON ITALY

M&C


2/6


, TALCWAITAs Italy goes ahead with nationwide construction and

mining projects, a number of worksites have one

important similarity the same project partner.

M&C reports fromthree of the most interesting loca-

tions. First, a series of tunnels to complete a major

motorway scheme in Sicily. Second, an unusual exam-

ple of small-scale mining in the Alps. And last, a long-

awaited road bypass to skirt the countrys largest lake.

5

All systems go in Italy: Excellent results are being achieved at these

three worksites just a few examples of many around the country.

PalermoPalermo

Brusada-Ponticelli mineBrusada-Ponticelli mine

MessinaMessina

Mori bypassMori bypass

Lake GardaLake Garda


3/6

6

TThe words Torre Finale, Piano Par-

adiso and Cozzo Mineria have an

exotic ring. Something to do with

Italian opera, perhaps? Not quite. They

are the elegant names of tunnels being

constructed along the Sicilian coastline.

The 250 km coastline motorway

between Palermo and the city of Messina

has been under construction from bothends for the past 10 years.

For most of the way, the sea is in sight

and the views are stunning. And where

the motorway is forced inland to avoid

coastal towns, the elevation increases dra-

matically and the highway becomes a

series of tunnels and spectacular viaducts.

Italian tunnelling contractors excel in

this kind of situation and those working

for Consorzio per le Autostrade Siciliane

(CAS), the consortium of contractors at

work here, are no exception. Some 26

km of twin tunnels are complete, exceptthe last missing link a 10.7 km tunnel

which is now being constructed.

Access to the two Torre Finale tun-

nels (1.02 km and1.07 km long) is via a

steep, unpaved construction road. The

portals have been established with a 12

m width and 40 m separation, and the

hillside around them is secured using

grouted cable bolts at 2 m intervals.

The first 54 m in each drive required

umbrella drilling, where inserted steel

pipes were pressure-grouted in position.

The fullface section is 98 sqm and this

achieved by driving a top heading in

advance and following on with bench or

trench, according to rock conditions. The

geology consists mainly of flysch.

Advanced drill rig

An advanced drill rig, an Atlas Copco

Rocket Boomer WL3 C three-boom unit,

is being used by contractor C.E.C Gitto,

to handle all the drilling. During M&Cs

visit, the rig was drilling 4.5 m-long

blast holes, but is equipped for up to

5.9m. The face is lightly shotcreted

before drilling, and only gelatine explo-

sives are used. The advance rate is some

50-60m per week.

In addition to Atlas Copcos Rig Con-

trol System (RCS), the rig features inter-


Torre Finale

Building t he missinglink on Sicily s

beaut if ul coast l ine

Site Manager Monaco Sebastiano (right) with

Atlas Copco Italias Ivan Sinibaldi: We

dont expect problems and we dont get them.

Francesco Ranazzo, Site Man-

ager: The WL3 C rig has ex-

ceeded our expectations.

Operator Filippo Parisi: The WL3 C seemed

an amazing machine, but after only a week, I

found it pretty simple to drive.

Making headway:

The Rocket Boomer

WL3 C drills 50, 70

or 90 holes in the top

heading depending

on the friability of

the rock.

SPO

TLIGHT

ON ITALY

M&C


4/6

7

OOne of the worlds most interesting

small mines lies at an altitude of

between 1,165 and 1,500 m in the

Italian Alps, north of Sondrio and just

five km from the Swiss border.

The Brusada-Ponticelli mine is

owned by IMI-Fabi, which owns the

rights to a 2,400 hectare sub-vertical de-posit of industrial talc. With a mining

width of 1565 m and an average of 25

m, the mineralised section at the mine is

1.2 km long over a vertical distance of

335 m and with an 800-metre cover.

IMI-Fabi, which recently achieved an

ISO 14000 rating, produces 150,000

tonnes per year of which some 40,000 is

waste and reserves are plentiful.

Extension drilling

The mine operates a room and pillar sys-

tem with 12 m-wide pillars and 6 m widerooms. After driving two 30 sqm access

drifts at top and bottom of the future

room, excavation starts with 25 m-high x

2 m-wide slots from the far end of the

top heading down to the lower level. Talc

is blasted in 22.8 m retreats.

An Atlas Copco Diamec 252 drill rig

is used for exploration drilling while an

Atlas Copco Boomer H 251 mounted

with a single COP 1238 drifter has been

working on development. These have

been joined by a Rocket Boomer M2 Ctwin-boom drill rig equipped with the

COP 1838 rock drill. The rig uses


Ioris Manfroi, MD of IMI-Fabi:Every

aspect of our operation will improve.

Brusada-Ponticelli

Winning

t alc f romt he A lps

w

active operator control panels, full

colour display of the computer-based

drilling system, auto-collaring and anti-

jamming protection.

The rock drills, COP 1838ME, have

an impact power of 20 kW and an impact

rate of 60 Hz with double reflex dampen-

ing. The advanced boom control system

(ABC Total) supports and guides the

operator in drill hole positioning and

alignment to reduce costly overbreak.The rig uses Secoroc Speedrods, T38-

R32, Hex35, length 5530mm.

Before the rig was started up, there

was some concern about it being located

far from the Atlas Copco Service Centre.

But a combination of the well-trained rig

operators, the customers efficient ser-

vice team and the rigs reliability re-

duced problems to a minimum most of

which were easily solved over the phone.

Poor rock

At the Piano Paradiso tunnels (2 x 2.88

km) the twin tubes are being umbrella

drilled throughout their entire length.

This is due to extremely poor ground

conditions in the area. Each 12 m-deep x

34-hole umbrella is reinforced with ce-

ment pressure-grouted steel tubes and,

due to the plasticity of the strata, it is

necessary to arch the invert and install a

reinforced concrete lining.

Access at the Messina end of the tun-

nels is so difficult that the portals have to

be established at different elevations. A

large flood culvert is being installed

across the front of the portals to provideadequate access for tunnelling.

The mudstone and soil strata has poor

strength characteristics and tunnelling

will most likely be as difficult as it is

proving to be from the Palermo end.

The two top headings at the Cozzo

Mineria tunnel site (2 x 2.48 km) are being

developed with steel arch and concrete

support throughout. The softer rock in one

heading is being broken using a hydraulic

hammer while a Boomer H174 drill rig is

at work in the other heading drilling blast

holes and bolting holes when needed.

There are multiple faults and disloca-

tions in the strata at the face, and

advance is proving a difficult task.

Dramatic and

difficult ter-

rain:The tow-

ering road

bridge and

Castelbuono

tunnels.


5/6

8

The Mori Bypass

All syst emsgo af t er adecade ofdelay

AAslowdown in the Italian construc-

tion industry in the early 1990s

was followed by a lack of funding

and resulted in long delays for the

Brenner Autostrada project.

So long in fact that the planned MoriBypass at the northern end of Garda,

Italys largest lake, has had to wait 10

years before a start could be made on re-

placing a part of the SS 240 motorway.

The project involves an intersection

with the motorway, a bridge which cross-

es it, a river and a railway, and twin tun-

nels 2.2 km-long with 90 m2 tubes to be

equipped with two lanes each.

Eighty per cent of the tunnels is being

driven in sedimentary rock and 20% in

volcanic rock. The contractor, Cari-

boniStrade e Gallerie, started construc-

tion work in October, 1999 and is using

two Atlas Copco drill rigs a Robot

Boomer 353E unit and a recently deliv-


Spreading its wings: The new Rocket Boomer WL3 C drilling rig at the mouth of the

twin-tunnel Mori bypass project, fully-computerised for contractor Cariboni.

ered Rocket Boomer WL3 C, fully com-

puterised and equipped with advanced

boom control (ABC Total). Secoroc

Speedrods T38-R32, Hex 35, length

6,100mm are also used.

High pressure

Before the portals could be established,

vertical micropiles were constructed

across the entrances and tied back with

25 metre, 60 tonnes ground anchors and

beams. The anchors were grouted under

high pressure with a cement mix, which

hardened for 10 days before being

attached to steel cross beams and pre-

stressed in sections.

ate support and safety and some 25,000

bolts have been installed so far.

A mixed fleet of loaders, including an

Atlas Copco Wagner ST 3.5 Scooptram,

has been strengthened by a new ST 1010with a 10-ton bucket. A Wagner MT 413

14-ton dump truck complements the

Penetration rate has been increased

from 1.20 m/min to 1.70m /min and pro-

duction increased from 80 dm/hour to 175

dm/hour. Standard Swellex 2.7 and 3.2 m

rockbolts are in widespread use and themine was one of the first in Italy to adopt

Swellex for its quick installation, immedi-

Secoroc Speedrods, T38-R32, Hex 35,

length 4,300 mm. Scaling is carried out

by an excavator equipped with an Atlas

Copco SBC 255 hydraulic hammer.

Ioris Manfroi, Managing Director of

the mine says: We decided to go for this

new type of rig and it has been a great

success. I am more than satisfied. In the

M2 C we have purchased capability thatwe now have to adapt to. Every aspect of

our operation will improve.

w

Caribonis Renato Lusi, Tunnel Manager

(left) and Luigi Cimenti, Drillmaster:

We are very satisfied with the new rig.

SPO

TLIGHT

ON ITALY

M&C


6/6

M & C 3 q0 1

Horizontal holes were then drilled

around the arches, into which steel tubes

were placed and pressure-grouted into

position to form micropile umbrellas.

Four umbrellas were needed in each tube

to reach stable ground. When the groundbecame rock, blastholes and minimum

explosive shook it up enough for hy-

draulic breaker excavation. The WL3 C is

equipped with the Atlas Copco rig con-trol system (RCS) and features operator

control panels with full colour display of

the computer-based drilling system.

Automatic functions provide highspeed drilling and outstanding drill steel

economy with the COP 1838 rock drill,

which achieves the maximum penetration

possible in any rock and maintains a high

hole quality with negligible deviation,

allowing easy insertion of explosives.

There is immediate identification of

faulty components and transfer of data

between office and drill rig by PC card.

Control system

ABC, the advanced boom control sys-

tem, guides the operator in drill holepositioning and alignment, helping to

reduce overbreak to a minimum.

The rig has also been used in semi-

automatic mode for face drilling while

its centre boom has been involved in

rockbolt drilling. Radial boltholes are

drilled at 1.5 m separation for 4 m-long

anchored and grouted bolts, followed by

steel arches at 1 m intervals with mesh

steel-fibre reinforced shotcrete.

loader fleet on long hauls. Virtually all the

mines loading machines are remote con-

trolled and can work in open stopes with-

out risk to drivers.

A tight team consisting of a director,

shift boss, maintenance fitter and 15miners work in shifts from 6am-10pm.

And a planned maintenance contract will

cover both the Rocket Boomer M2 C rig

and the Wagner ST1010 loader the firstcontract of its kind in an Italian mine.

Scooptram in thesnow: The ST 1010

comes to the surface

of the talc mine for a

change of shift. In the

foreground, visiting

the site is Antonio

Belcastro, General

Manager, Atlas

Copco Italy.

tunnels and a ten years

Documents