External post tensioning repair strengthened one 18-foot length, 108-inch diameter PCCP. Fifty three separate strands stressed to 47 kips each where used. Shotcrete replacement of original concrete shell was completed after installation of strand. Internal strengthening of three additional lengths of pipe using carbon fiber polymer materials was included.
1. High risk safety requirements in industrial power plant. Zero reported incidents.
2. Work completed on schedule and on-time during 10 calendar day shutdown.
3. Definition of work scope completed during construction phase of project.
Field Problems Encountered:
1. High ground water table at soil excavation for external pipe strengthening.
2. Determination of actual project scope delayed until completion of investigation completed at the outset of 10 calendar shutdown.
3. Discovery of cracking arrested by steel liner hindered repair process.