The University of Quebec Campus expansion in downtown Montreal occupies three city blocks. The complex consists of interconnected buildings varying from 3 to 10 stories in height with two basements. The internal columns of the superstructure are founded on footings and caissons. The peripheral walls are carried on a slurry trench excavated, tremie concreted wall, which also served as the earth retaining structure during construction. There are no records available on soil supported slurry walls in Canada although it is a common system in Europe.The slurry trench tremie concrete wall could have been extended to bedrock and the loads carried on rock; however, the amount of increased wall area was significant. Support in the till would result in large savings; however, this required the determination of the bearing capacity and compression characteristics of the till.Tests were carried out to determine concrete-to-till friction, both with and without bentonite slurry on the till-to-concrete surface contact. In addition, the end bearing capacity of the till was obtained by plate load tests.This paper gives the results of the tests carried out, compares them to similar results reported in the literature, and gives the design solution adopted.
Monitoring drying and wetting of a cement bentonite mixture with Electrical Resistivity Tomography