Numerical modeling of buried pipes with flowable fill as a backfill material

The objective of this research work was to perform a numerical analysis of pipe deformations when flowable fill is used as a backfill material around buried plastic corrugated pipes. The flowable fill materials used in this study contained varying proportions of fly ash, bottom ash, river sand, and cement. The stiffness properties of CLSM backfill materials were back calculated from experimental data obtained under various trench width ratios. The stiffness properties of HDPE pipes were calculated based on the data provided by the pipe manufacturer. Finite element models of HDPE pipes with varying trench widths were developed for laboratory conditions. The experimental variables included: trench width, pipe diameter, in-situ soil strength, backfill strength, and external loading. The numerical results were compared with that of the experimental data. In addition to modeling laboratory conditions, finite element models for 18-inch (45.7 cm) and 24-inch (61 cm) diameter pipes were developed for field conditions. (Abstract shortened by UMI.)...