Case Studies

Project Type
WATER MANAGEMENT
Location
BANFF NATIONAL PARK, ALBERTA, CANADA
Length / Hole Diameter
20 m (65 ft); 3.4 m (11 ft) diameter Steel Casing
Divisions
The Tunneling Company

BANFF RAIL LINE

DRAINAGE/ MIGRATION CULVERT

Project Summary

In 2013, a “100-year flood” overwhelmed infrastructure in Calgary and surrounding regions. This included a section of rail line between Banff and Canmore. When a bridge along the line collapsed, it was determined the existing culvert system needed to be relocated and expanded if it was to protect the tracks against future flooding. The plan called for the installation of a large 3.4 m (11.2 ft) diameter culvert under the rail line, which would not only handle runoff – but also serve as a crossing corridor to keep wildlife off the tracks.

The railway was to remain operation during installation. As a shallow cover installation, a miscalculation could damage the tracks.

Key Challenges

Settling can be an issue when installing pipe of this size using traditional tunneling techniques. The Tunneling Company recommended using its proprietary Hydrohammer™: a pneumatic pipe ramming system engineered for the safe installation of large diameter steel pipe. The Hydrohammer had not been used on pipe of quite this diameter, but The Tunneling Company had complete confidence it was up to the job. There was some urgency to complete the installation in advance of the upcoming flood season, so it was scheduled in January. The installation was successfully completed in one week, with an additional week required for preparation and backfill.

Services Provided

PIPE RAMMING (HYDROHAMMER™)

TUNNEL BORING / PIPE JACKING

Tunnel Boring and Pipe Jacking Systems are used to hydraulically install underground pipelines up to 4.2 m (168 in) in OD range within strict alignment and grade tolerances. The likelihood of settling or sloughing is very low. Wheel machines are equipped with various cutter heads and sand shelves. A closed-face attachment is available for boring in unstable ground conditions. This versatile system can be easily adapted to work with any jacking pipe, in any pipe joint length. It can accommodate a wide range of pipe diameters.

Tunnel Boring Machines are used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through hard rock, sand, and almost anything in between. Tunnel diameters can range from 1 m and exceed 15 m (3 ft to 49 ft).

The Crossing Group - The Tunneling Company - Tunnel Boring - Pipe Jacking - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

SLIP BORING

A boring technique commonly used for installing oil & gas pipelines ranging from 51 mm to 1067 mm (2 in to 42 in) in diameter without leaving casing in the ground. Product pipe is welded to steel casings and either pushed or pulled through the ground in sections. The casing is cut off and removed, leaving just the product pipe. Maximum installation length is 150 m (492 ft).

The Crossing Group - The Tunneling Company - Slip Boring - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

DOWN THE HOLE HAMMER

A pneumatic hammer is attached to the inside edge of the casing. The front of the DTH breaks cobles, boulders and even solid rock into small pebbles or dust. The spoil makes its way through the hammer and into the casing, where it is removed by airway augers.

The Crossing Group - The Tunneling Company - Down The Hole Hammer - DTH - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

GUIDED BORING

A Guided Boring Machine (GBM) is used to install 305 mm to 3.6 m diameter pipe (12 in to 144 in) with grade and alignment precision. It is commonly used for installations 50 m to 150 m in length (164 ft to 492 ft) or when line and grade accuracy is critical in displaceable soil. Our GBM is extremely versatile and our customers continually approach us with new applications.

The pipe installation involves a two-step process where launch and reception shafts are strategically located to minimize surface disruption. A pilot tube with a theodolite guidance system is then pushed through the ground at the precise grade and alignment specified in the design into the reception shaft. A reaming head is welded to the pilot tube and the casing and the pilot tube is used as a guide to install casing. The GBM can be used in conjunction with auger boring or pipe ramming methodologies.

The Crossing Group - The Tunneling Company - Guided Boring - Trenchless Construction - Tunneling - Augering, Boring & Pipe Ramming

PNEUMATIC PIPE RAMMING

Pipe Ramming is used in a wide variety of soil types including gravel, cobble or sand. A pneumatic hammer is attached to the back of the casing pipe and driven through the material at any angle: from horizontal to vertical. The material is cleaned out of the pipe using an auger boring machine. Pipe Ramming methods are used for pipe diameters of 305 mm to 3.6 m (12 in to 144 in).

The Crossing Group - The Tunneling Company - Pneumatic Pipe Ramming - Tunneling - Augering, Boring & Pipe Ramming