Field Tests of Grouted Rod Anchors in Permafrost

Field tests of grouted rod anchors installed in permafrost ( frozen, stratified clays and silts containing ice at about 31.5 degrees F) at two test sites in northern Manitoba are described. The test program was undertaken to evaluate the resistance of frozen soils to uplift forces and, in particular, the time-dependent behaviour (creep) of frozen soil under load and the displacements associated with it. A theoretical analysis of the test results, based on engineering creep theory shows how the time-dependent behaviour of grouted rod anchors (or short piles) can be related to the basic creep parameters of frozen soil. In addition, it is shown how field creep data may be used for estimating long-term adfreeze strength of frozen soil of the design of anchors or piles.