78" & 84" Cast-in-Place Reinforced Concrete Pipe

Project Location
Sims Bayou area - Houston, Texas
Construction cost
$5,056,311 - $7.80/ID in-ft
Construction Start/End
08/1998 - 06/1999

Details

When was it constructed and how long has it been in service:
Unknown age, but severely corroded in upper 1/2 of pipe.
Dimensions:

Diameter of line, sewer pipe material (RCP, MCIP, brick, etc.), length of rehab portion:78"/84”, Cast-in-place reinforced concrete pipe, 8164/279 linear feet.

Depth of pipe:
13 - 15 feet to crown.
Depth of ground water:
Ground water 1.0 – 5.0 feet above pipe crown.
Health and safety:
Used conventional confined space entry program.
Has any re-inspection been performed? What was the condition of the pipe?
No
References

Ken Korb, P.E.
Pate Engineers
Telephone: 713-462-3178
Project: GFS #R-2002-01-3, File No. 4707-1

Methodology

Ventilation and odor control used:
Fresh air pumped into pipe at upstream manhole, and suction fan at downstream manhole to provide adequate ventilation during the work periods.
Rehab method used:
Danby Panel Lok with full annulus grouting with cementitious grout with minimum compressive strength of 5000 psi.
Cleaning method used (if required) and who cleaned the line:
High pressure (10,000 psi) water blasting performed by the Danby licensee (Kinsel Industries, Inc.).
Method of flow bypass or diversion, if used:
Flows 100% pumped bypass.

Hurdles

Problems encountered during construction:
Due to construction method used in building this pipe, variations in alignments (both horizontal and vertical) and in wall thickness were severe. The Danby liner installed was 72”-75" ID with alignment adjustments at discrete location as required. Due to high flows from side sewers in the downstream portion of this line, the 84” section was sliplined with Hobas FRP pipe.
Problems encountered after construction:
None