Effect of Using Postmanufacturer HDPE Compounds on the Behavior of Landfill Leachate Collection Pipes

In recent years, HDPE plastic pipe producers have begun to recycle waste generated from their own production. However, there are some concerns with regard to the effects of using postmanufacturer recyclable HDPE compounds (RCs) on the long-term performance of pressure pipes. Because the failure phenomena of landfill leachate collection pipes are fundamentally different from those affecting pressure pipes, it is possible that these RC materials can instead be used in the production of landfill leachate collection pipes. In order to develop a better understanding of the effects produced by using RCs on the performance of leachate collection pipes, a series of different laboratory experiments is performed. The pipe deflection ratio (DR) and settlement of the soil surface (SSS) are used to define the consequences. According to these results, although the maximum DR and SSS of the pipe samples slightly increase with the addition of RCs, the results are almost the same. Hence, the addition of RCs has no significant effect on the behavior of these gravity pipes. In addition, this research investigates the effects produced by perforations, magnitude of construction loads, and buried embedded depth of pipes ($\mathit{H}/\mathit{D}$).