Trenchless

TRENCHLESS TECHNOLOGY

Pipe bursting yields the highest increase in hydraulic capacity of any trenchless sewer construction method. In keeping with this wave of modern technology, D’Allessandro Corp. prides itself on the usage of these methods. The video on the right features a trenchless pipe bursting method similar to that which we utilize.

Trenchless Technology Methods

In keeping with modern technologies, D’Allessandro Corp. specializes in trenchless technology, a less invasive alternative than traditional techniques.

Pipe Bursting
Pipe Ramming
Pipe Jacking
Auger Boring
Cast in Place Pipe Lining
Slip Lining

Pipe Bursting

Why Choose Pipe Bursting

When considering methods for pipe replacement or excavation jobs, several factors, such as project size, difficulty, risk level, and market conditions, need to be considered when evaluating solutions. Generally, pipe bursting proves more economical and less difficult than traditional methods. This is especially true with jobs where service connections are fewer, surface areas are paved or improved, obstacles like water bodies or roadways exist, or environmentally sensitive areas like wetlands are present. Other factors include conflicts with utilities, soil contamination, or the need to minimize site disruption.

INCREASES FLOW CAPACITY:

Pipe bursting offers the key advantage of increasing flow capacity by installing pipes of the same size or larger. In comparison to traditional upsizing pipe replacement, bursting achieves this goal with reduced risk, lower costs, and shorter timeframes.

ACCESS ISSUES:

Traditional excavation can present costly conflicts with underground access and existing utilities. Delays are common due to permitting requirements and technical obstacles. Employing pipe bursting to traverse these surface obstacles reduces time, expenses, and disruption to the public.

REDUCED TRENCH SETTLEMENT:

Excavation projects, even well-executed ones, carry the risk of subsequent trench subsidence and pavement settlement. As trenches settle, nearby utilities can also suffer damage as fill and surrounding soils shift. This damage to other utilities may become apparent shortly after trench settlement or even long after. Pipe bursting eliminates most of these issues.

AVOIDANCE OF HAZARDOUS MATERIALS:

If surrounding soil is contaminated, bursting through the pipe circumvents the need for testing and disposal of soil-related issues. In cases of extensive contamination, strategically placed access pits for pipe bursting minimizes the amount of contaminated soil requiring disposal.

WHERE REHAB ISN’T THE SOLUTION:

When rehabilitation is not feasible, the owner/engineer turns to replacement and pipe bursting is often the preferred solution. Here are a few examples:

Where an existing pipe is severely “squatted” (i.e., excessive ovality), beyond the amount that can be addressed by cured-in-place pipe (CIPP)
When there is uneven deterioration of concrete pipe where a “shelf” is created above the flow line of the pipe

ADVANTAGES OF PIPE BURSTING:

The pipe bursting method of replacement is a safer, more cost-effective, faster, less disruptive, and lower-risk alternative to traditional pipe replacement methods.

Specifications

To guarantee a quality pipe bursting project, several factors specific to the site and interrelated variables must be taken into account when creating a specification and plan These factors include:

Existing pipe material and condition
Geometry of the host pipe (diameter, bends, etc.)
Access to the site
Flow capacity and up-sizing requirements
Location and type of pavement, other utilities, and structures
Original trench geometry (width and depth)
Desired replacement pipe material
Other site conditions

We suggest that engineers customize variations of base specifications to suit the requirements of each project.
For specification drafts, please contact us.

Installation Methods

Our goal is to provide cutting-edge technology, tools, and procedures. We thoroughly assess each job to determine the most suitable method. We utilize two types of pipe installation: pneumatic and static.

PNEUMATIC PIPE BURSTING

In pneumatic pipe bursting, a steel cable is placed in the existing pipe, connecting the receiving manhole/pit to the insertion pit. The pneumatic tool, expander, and new pipe are then placed into the insertion pit and attached to the cable. As the assembly is guided and pulled back through the pipe, the pneumatic tool’s percussion fractures the host pipe into the surrounding soil, while simultaneously pulling the new pipe into position.

Above and below: Breaking and expanding old pipe as new pipe is inserted.

Reversible pneumatic tool methods eliminate one pit.

STATIC PIPE BURSTING

In the static method of pipe bursting, segmented steel rods are inserted into the existing pipe, connecting the receiving manhole/pit to the insertion pit. The end of the rod is attached to bladed cutting rollers, an expander, and the new pipe. As the assembly is pulled back through the pipe, the roller blades split the pipe, and the expander displaces the host pipe into the surrounding soil, while the new pipe is simultaneously pulled into position.

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