General Observations of Natural-Alluvial and Lifeline Systems

1. Liquefaction of the Alpine glacial rivers during the M7.9 Denali fault earthquake of 3 November 2002 was controlled by tectonics (ponding of sediment behind faults; steepness of terrain); geologic properties of mainstem and side entering glacial river systems; and the intensity and directivity aspects of the strong ground shaking.
    
   
2. Near the fault crossing of the Trans-Alaska pipeline, strong shaking, inertial motions, and permanent offset (5.5 meters right-lateral offset and 0.6 meters vertical) beneath the pipe resulted in damage to 8 horizontal support members, and 9 anchored supports near the fault crossing. These affects were not critical to the integrity of the pipeline, that as designed to withstand 6 meters of lateral offset and 1.5 meters of vertical slip. The Trans-alaska pipeline performed remarkably well during the event.
    
   
3. Geotechnical and structural lifeline damages appeared to be focused towards the eastern end of the Denali-Totschunda fault rupture area. Directivity effects of the unidirectional rupture are the apparent reason. Kinematic modeling of the rupture mechanics support the field observations of amplified damage to the east.

 
Abstract | Index Map 1 | Liquefaction and Ground Displacement | Spacial Character | Surface Wave Testing
Index Map 2 | Liquefaction Damage at Northway Airport | Earthquake Effects on the Trans-Alaska Pipeline
SASW-Site Characterization of Pump Stations 9,10 &11 | Acknowledgments | General Observations | About These Web Pages
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