docFirst PVC Spiral Wound Liner Installation in Hawaii
download 
Report Transcription
First PVC Spiral Wound Liner Installation in Hawaii
Lining the Slippery Slopes of Wilhelmina Rise Honolulu’s First Installation of PVC Spiral Wound Liner and Lateral Part-Liner 32nd Annual HWEA Conference Presented by: Shannon Holman, PE, URS List of Credits • Owner: City and County of Honolulu – Project Design Engineer: Lynn Kurashima – Construction Engineer: Ted Saito • Design Consultant: URS Corporation • Contractor: Parsons • Construction Manager: Yogi Kwong Engineers Presentation outline • Project background • Condition assessment • Rehabilitation methods evaluated and design approach • Construction – Installation challenges – Observations – Lessons learned Project located along Wilhelmina Rise Project consists of ~ 40,000 LF of gravity sewer and over 500 laterals Kaimuki Community Park Sierra Dr Maunalani Park Wilhelmina Rise Waialae Ave 16th Ave • • • • 6-, 8-, 10-, and 12-inch pipe Minor and major root intrusion Legend Cured-in-Place Pipe Structural damage Joint offsets Open Cut Pipe Replacement Condition assessment identified various defects: collapsed pipe, fractures …..pipe cracking….. …..and minor and major root intrusion Various rehabilitations methods evaluated for project • Cured-in-place pipe (CIPP) • PVC spiral wound pipe (Rib Loc) • Service connection lateral liners – Top-hat liner – Lateral part liner (T-Liner) Difficult access along East and West lines results in Rib Loc being the selected method Kaimuki Community Park Sierra Dr Maunalani Park Wilhelmina Rise Waialae Ave 16th Ave Legend Cured-in-Place Pipe (CIPP) Rib Loc or CIPP Open Cut Pipe Replacement Description of Rib Loc installation 1) Pre-cleaning 2) Lateral logging 5) Lateral reconnection PVC liner spool 3) Winding process Cutting wire 4) Expansion Process Description of T-liner installation 1 Clean and inspect lateral to main connection 2 T-liner inspected, coated w/ resin, & loaded into t-loader device Description of T-liner installation 3 T-Liner loader inserted through mainline pipe 4 T-liner loader is aligned with lateral connection opening Description of T-liner installation 5 T-liner is inverted into lateral Construction overview • Schedule duration – 12 weeks for Rib-loc installation – 4 months to date (300 out of 500 T-Liner installations) • Training requirements • Remote location, steep terrain and limited access Rib Loc equipment Silicone Generator Wire puller Hydraulic power pack Rib Loc profile on spool Control panel Rib-loc equipment set-up Rib Loc installation Rib Loc installation Rib Loc installation – lateral cutout Remote cutter machine T-liner wet-out procedure T-liner (wetted out) Inflatable bladder T-liner tube T-liner installation at manholes T-loader positioner T-Liner Installed T-liner O-ring gasket Smooth transition from liner to host pipe Lateral portion of T-liner Challenges and lessons-learned for Rib-loc installation • • • • • Mobilization plan Rapid root re-growth Modification to manholes Measure twice, cut once (laterals) Flow bypassing not required for low flow conditions • Air testing constraints Manhole modification required to install Rib Loc in steep grades Mobilization plan in tight quarters Observations and challenges for T-Liner installation • • • • • Cleanout requirement for 3rd access point Double wye lateral connections Occasional o-ring gasket detachment Excess resin, resin bumps Occasional failures during initial installations Double wye lateral connection O-ring detachment Exposed o-ring gasket on lateral portion of T-Liner Second o-ring gasket Exposed o-ring gasket on mainline portion of T-Liner Excess resin Rib Loc Conclusions • Appropriate for this application • Equipment was portable and easily transported • Immediate confirmation on installation allowing for removal if necessary • No curing process • Can improve hydraulic capacity • Uses existing MH’s for access • No sewer bypass for low flow conditions T-Liner Conclusions • Allowed for less disruption to property owners • Full circumferential seal – awaiting air test results • Uses existing MH’s for access • Hydrophilic gaskets on mainline and lateral provides better seal Questions ??
