The effect of installation procedures on the field performance of existing high-density polyethylene (HDPE) pipe used for drainage applications on highway projects was investigated. A total of 45 HDPE pipes were inspected at sites in South Carolina that were statistically selected based on geographical location, pipe diameter, use, and age. The condition of each pipe was not known prior to selection for inspection. Both the external and internal conditions of the pipe were evaluated with respect to AASHTO and ASTM specifications, measurements of pipe deflection with a mandrel set to 5% deflection, and visual inspections of the pipe interior using a video camera. The video camera inspections revealed circumferential cracks in 18% of the pipes, localized bulges in 20% of the pipes, and tears or punctures in 7% of the pipes. Deflections greater than 5% were observed in 20% of the pipes. Installation problems such as poor preparation of bedding soils, inappropriate backfill material, and inadequate backfill cover contributed to the excessive deflection and observed internal cracking in pipes with observed damage. Appropriate construction procedures are essential in achieving a proper installation.
• Gas Gathering
• Crude Oil Flow
• Water Flood
• Saltwater Disposal
• Supply Water
• Fuel Transfer
• Main Lines
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