This report documents the installation of the Hydraway edge drain (version two) on 1-64 in Franklin·Woodford-Scott and Fayette Counties. The edge drain was placed on the back side of the trench against the shoulder and backfilled with a sand/slurry.
From observations on this project and several previous projects, the sand/slurry backfill helps to insure the integrity of the drainage system during initial backfilling. It is apparent that the sand slurry backfill provides a better installation in comparison to previous methods using excavated trench material. Notable trench settlement did occur on this project. It is apparent that insufficient water was used to properly densify the sand. From observations on other projects, it appears that approximately one gallon per linear foot is required to achieve proper density. It appears that the method of flushing the sand, the speed of the construction, and the amount of water needed to achieve proper density will vary on the contractors equipment and methods. The net result is to achieve proper density with out damaging the edge drain. It also appears that the initial asphalt plug is not being properly compacted.
The Hydraway panel was reversed to minimize fabric intrusion into the core of the drain. Fabric intrusion into the inner core of the Hydraway drain appeared to be eliminated when the panel was reversed. When the panel was reversed and trench settlement occurred, the rigid back of the panel was forced to bend in the opposite direction it was designed. The net result was cracking occurring in the rigid backing.
Information reported in Research Report KTC-91-10 "Evaluation of Headwalls and Outlets for Geocomposite Edge Drains on 1-75 and l-71" indicates that 48 percent of the flexible outlet pipes that were inspected were less than 60 percent open. Approximately 10 percent of the rigid outlets inspected during this study were less than 60 percent open, thus showing a substantial increase in performance. A large amount of distress noted on 1-64 was observed in the flexible 4-inch pigtail. If rigid pipe is used throughout the outlet pipe system, performance should increase.
Digital Object Identifier
Fleckenstein, L. John and Allen, David L., "Construction Evaluation of Hydraway Edge Drains and Outlet Pipes on Interstate 64" (1991). Kentucky Transportation Center Research Report. 664.