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environmental intrusion. Pipe bursting creates minimal interfer-
ence with other utilities and less safety hazards (for both operators
and the public) due to reduced open excavation.

6.7 Pipe Bursting Project Classification
The ASCE Pipe Bursting Manual of Practice (ASCE, 2007) classifies
bursting projects into three categories, in terms of difficulty: Class
A—routine, Class B—moderately, difficult to challenging, and Class
C—challenging to extremely challenging. The characteristics defin-
ing the appropriate classification are provided in Table 6.1, based on
these criteria. Note that the degree of difficulty increases as more than
one of the above criteria applies (ASCE, 2007).

6.7.1 Pipe Bursting Applicability and Limitations
Pipe bursting is used to replace waterlines, gas lines, and sewer
mains, as well as sewer lateral connections. Typical replacement
length is between 300 ft and 500 ft; however, in favorable conditions,
longer drives have been completed successfully. The size of pipes
being burst typically ranges from 2 to 30 in., although larger size

A B C
Criteria Routine Moderately Challenging
Depth Less than 12 ft 12 ft–18 ft More than 18 ft
Existing 4 in.–12 in. 12 in.–20 in. 20 in.–36 in.
pipe
New pipe Same size or one Two diameter upsize Three or more
diameter diameter upsize diameter upsize
Burst Less than 350 ft 350 ft–450 ft More than 450 ft
length
Trench Relatively wide trench Trench width less Incompressible
width compared to upsized than 4 in. wider than soils (very dense
diameter upsize diameter sand, hard clay
or rock) outside
trench
Soil Compressible soils Moderately Constricted trench
outside trench (soft compressible soils geometry (width
clay, loose sand) outside trench less than or
(medium dense to equal to upsize
dense sand, medium diameter)
to stiff clay)
TABLE 6.1 Pipe Bursting Classification (ASCE, 2007)