PMH1 - Cape Horn CP Extension and Relocation
Location: Coquitlam, BC
Client: H5M Joint Venture
The scope of work included relocation of a main sewer line, track bed design for CP mainline and yard tracks, ground improvement generally through surcharging to mitigate settlement issues, rail embankment design for soft subgrade, foundation design for a railway bridge, utility protection, construction impact assessment, and seismic evaluation.The total value for the onshore works at the Cape Horn interchange was estimated to be about $700 million.
M+EG was responsible for the following activities:
- Site investigation (mud rotary drilling, CPT and shear wave velocity measurements).
- Definition of engineering parameters to define ground improvement and track bed requirements.
- Construction impact assessment for existing tracks and utilities.
- Pile foundation design for railway bridge structure.
- Foundation design for protection structures at King Edward and Kinder Morgan pipeline.
- The presence of peat and organic materials was critical in the assessment of the foundation bearing capacity and stability of the track bed structure, as well as potential foundation settlement. A detailed testing program was defined to evaluate the strength of the critical layer.
- The rail relocation was on the critical path of the highway expansion project in Cape Horn. To ensure the rail relocation meeting the construction schedule, additional efforts were required to detail the ground improvement and construction sequence.
- To assess the construction impact of placing the required surcharge fill adjacent to the existing tracks, finite element stress-deformation analyses were performed using a calibrated soil model.