A hydraulic jack extends from a reaction frame bolted against a sheet pile wall, its digital gauge tracking pressure increments while a dial indicator measures tendon elongation to 0.01 mm. This is a proof test on a multi-strand anchor installed through glacial till into the underlying shale of the South Slope in Pickering. The city’s topography—dissected by the Duffins Creek and Petticoat Creek valleys—creates frequent demand for anchored retaining systems where cuts exceed 4 m. Since the 2011 update to the Ontario Building Code requiring full-scale testing on production anchors, verification has become systematic rather than optional. We combine deep excavation monitoring data with load-displacement curves to confirm that both active prestressed anchors and passive ground anchors meet the 60 percent ultimate capacity threshold before lock-off.
A properly documented anchor test tells you more about the ground than the anchor itself—the load-extension curve is a direct signature of the soil-grout interface behavior.
