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Construction and Inspection for Cur ed-in-Place Pipe 297
7.7 Quality Assurance and Testing
7.7.1 CIPP Inspection and Acceptance
The CIPP installation may be inspected visually if appropriate. Addi-
tionally, CCTV is commonly used for pre- and postinstallation inspec-
tion purposes. Variations from true line and grade may be inherent
with CIPP because of the conditions of the existing pipe. However,
certain conditions must be met, such as the new CIPP should not
show any infiltration of groundwater. At the conclusion of the instal-
lation, all service connections must be accounted for and reconnected.
Table 7.8 presents sample defect codes for CIPP lining evaluation.
7.7.2 Workmanship
The CIPP should be continuous over the entire length of an installa-
tion and be free of dry spots, lifts, and delaminations. If these condi-
tions are present, the CIPP will be evaluated for its functionality to
meet the applicable requirements of the contract documents. If the
CIPP does not meet the requirements of the contract documents or the
functions expected based on the technical specifications, the affected
portions of CIPP may have to be repaired according to the contract
provisions. Some project owners may apply a penalty in addition to
the CIPP repair and/or replacement requirements (see following sec-
tions). See Sec. 2.8 for sample CIPP technical specifications.
7.7.3 Quality Control Issues
Design Issues
The key design consideration in CIPP liner installation is the ability of
the cured-in-place pipe to withstand buckling due to ground water
Defects Codes Defects Codes
Lining shrinkage LS Lining bubbles LB
Lining wrinkles LW Lining fins or folds LF
Foreign inclusions FI Lining delamination LD
Lining cracks LC Hot dogs HD
Dry spots DS Mis-cuts MC
Lining wrinkles LW Annular space AS
Lining elongation LE Lining thickness LT
Lining dimples LD Lining lumps LL
Under-cuts UC Overcuts OC
TABLE 7.8 Sample Defect Codes for Pipeline Lining Evaluation