| This thesis examines the interface friction characteristics and full-scale testing of sandbag dikes under simulated flood conditions. A laboratory testing program and a full-scale testing program have been conducted to assess the performance of sandbag structures built according to the City of Winnipeg's 1997 design template.; The laboratory testing program consists of large-scale and bench-scale direct shear tests on soil-geosynthetic, grass-geosynthetic, and geosynthetic-geosynthetic interfaces representing the material interfaces that exist in sandbag dikes. The large-scale shear apparatus used has a 1.0 m2 interface area, which minimizes edge effects on the interaction between the surfaces being tested. Bench-scale direct shear tests using a typical direct shear apparatus are also conducted for comparison with the large-scale results.; The full-scale testing program is conducted in a modular test facility built at the University of Manitoba. The sandbag dikes are instrumented and monitored internally and externally for horizontal and vertical deformation, pore pressure, total stress changes, and leakage rates during all stages of loading and failure.; The results of the laboratory testing program are summarized using interpreted Mohr-Coulomb failure parameters to quantify the cohesive and frictional characteristics for each interface. The results of the full-scale testing program are summarized with respect to stability and seepage rates measured for a given dike height and geometry. The importance of the results with respect to understanding the behaviour of these important flood protection structures is presented. |
