Burnaby's subsurface is dominated by glacial till and advance outwash deposits, with the water table often sitting less than 4 meters below grade near Burnaby Lake and the Fraser River lowlands. For deep excavations in this setting, sheet pile wall design must account for high lateral earth pressures from stiff clays and the potential for seepage through sand lenses. Before finalizing the wall embedment, we typically correlate blow counts from a local ensayo SPT to estimate the friction angle and undrained shear strength of the till. That direct field data anchors every calculation we make.
Sheet pile wall design in Burnaby must reconcile stiff glacial till with a high water table and moderate seismic demand — a balance that requires site-specific soil parameters.
Service characteristics in Burnaby
Typical technical challenges in Burnaby
Driving sheet piles through Burnaby's dense till requires high-energy vibratory hammers, and in some areas near the Burnaby Mountain terminal, the till contains cobbles and boulders that can cause pile refusal or damage. When refusal occurs, we switch to pre-drilling with a 1.2-meter auger to create a pilot hole. The sheet pile wall design must also manage the risk of hydrostatic uplift during dewatering; we install relief wells and monitor piezometric levels weekly to prevent bottom heave in the excavation.
Our services
Our sheet pile wall design service covers the full workflow from soil characterization to construction support. We tailor each solution to Burnaby's specific ground conditions.
Cantilever Sheet Pile Walls
For shallow excavations up to 6 meters in stiff till, we design cantilever walls with no lateral support. We calculate the required embedment depth using limit equilibrium and check against overturning and sliding per CSA standards.
Anchored Sheet Pile Walls
For deeper cuts or where lateral displacements must be minimized, we design single or multi-level anchored walls with tiebacks grouted into the till. Each anchor is proof-tested to 1.33 times the design load.
Dewatering Integration
We integrate the wall design with a dewatering plan that includes wellpoints, sumps, and relief wells. The design accounts for seepage rates through sand seams and checks against piping failure.
Seismic and Vibration Analysis
We perform pseudostatic seismic analysis per NBCC 2020 to verify wall stability during an earthquake. For vibration-sensitive sites, we recommend low-vibration installation methods like press-in piling.
Frequently asked questions
How long does a typical sheet pile wall design take for a Burnaby project?
A preliminary design can be completed in 5 to 7 business days if soil parameters from a recent site investigation are available. A full design with seismic checks and construction drawings usually takes 2 to 3 weeks.
What is the typical cost range for sheet pile wall design in Burnaby?
The cost for sheet pile wall design in Burnaby typically ranges between CA$2.100 and CA$6.150, depending on wall height, number of anchor levels, and whether seismic analysis is required. This includes field correlation of soil data and a design report sealed by a professional engineer.
Do I need a geotechnical investigation before the wall design?
Yes, we always require at least one borehole per 30 meters of wall alignment. The investigation must include SPTs and groundwater monitoring to provide the friction angle, cohesion, and water level data necessary for the design.
Can sheet piles be installed in Burnaby's glacial till without pre-drilling?
In most areas with stiff till, pre-drilling is recommended to avoid pile refusal and to maintain vertical alignment. We specify a pre-drill diameter slightly larger than the pile section, typically 1.0 to 1.2 meters, to reduce driving resistance.