Mid-Halton Outfall Tunnel Overbreak Evaluation

摘要

As part of recent wastewater facility upgrades for Halton Region, Ontario Canada, an outfallrnsewer tunnel will be constructed to convey treated effluent from the treatment plant to discharge into LakernOntario. The 3.6-meter diameter, 6,255 m long tunnel will be mined through Georgian Bay shale that isrninterbedded with limestone and siltstone.rnThis paper presents the design methodology used to predict overbreak risk using two-dimensional finiternelement modeling. Overbreak is evaluated by coupling the material behavior with three Tunnel Boring Machinern(TBM) shield and support configurations: main beam with actively-propped support, main beam with fingerrnshield, and single shield.