Page 98 - Trenchless Technology Piping Installation and Inspection

Existing Pipeline Renewal and Replacement Methods 65

Start

Pressure pipe
Solution to problem Renewal methods
Yes
Structural Flow capacity Pipe Yes Replace with Pipe bursting
problems? evaluation undersized? larger size pipe open-cut method
No

Holes or No Semi-structural Class III linings
cracks? liner
No
Yes Structural liner Class IV linings
Pipe bursting
Replace pipe
open-cut method
Hydraulic Yes Flow capacity Pipe Yes Replace with Pipe bursting
problems? evaluation undersized? larger size pipe open-cut method
No Semi-structural Class III linings
No
Structural liner Class IV linings
Joint Yes Point source
leaks? Repair joints repairs
Nonstructural Class I & II
No liner linings
Semi-structural Class III linings
liner
Water quality Yes
problems?
Structural Class IV linings
liner
No
Pipe bursting
Replace pipe
No action open-cut method
necessary*
Class I & II methods Class III methods Class IV Point source
lining lining methods lining repairs
End 1. Cement-mortar 1. Cured-in-place pipe 1. Close-fit pipe 1. Chemical gel grouts,
lining 2. Polyurea lining 2. Cured-in-place pipe cement-based grouts
2. Epoxy lining 3. Polyurethane lining 3. Sliplining 2. Epoxy resins, cement
*Continue to monitor based on 4. Thermoformed pipe mortar
your asset management plan 3. Internal seal
and pipe material and condition 4. Point CIPP
requirements.
FIGURE 2.14 Decision support system for pressure pipe renewal methods.
recommendation for specific conditions and requirements of a proj-
ect, so it is recommended that consulting and design engineers work
with project owners to rank and weigh project priorities and then
make recommendations for specific methods. The selected methods
can then be advertised for bids.