DEVELOPEMENT OF NEW PROCEDURE FOR LIQUEFACYION STUDY IN EASTERN CANADA

Since 2005, the National Building Code (NBC) requires a systematic analysis of the potential of soil liquefaction of soil deposits. This exercise has a significant impact on the design of infrastructure and civil engineering projects in general, both in terms of cost of soil treatment that the choice of the foundation type. A better understanding of the liquefaction phenomenon in the context of seismic Eastern Canada may have significant impacts on the methods of foundation design and the costs of constructions. Indeed, the liquefaction problem is relatively known in parts of the world with high seismicity (United States, Japan and China), but remains poorly documented for parts of Eastern North America because of the lack of 'historical events. In practice, the evaluation of the liquefaction potential is generally based on the charters established from observations following earthquakes in the US, Japan and China. Due to lack of experience and data in Eastern North America, liquefaction charts are still used in current practice even if they were developed in different seismic contexts. These charters seem to be accepted by practitioners in the United States and significant seismic experience shows that they can meet the seismic requirements. However, nothing indicates that the use of these charters: 1) does not result in designs rather overestimated and 2) do not have a high degree of uncertainty to respond realistically to the seismicity of the East Canada, which is different from that of the West. The fundamental difference between the seismicity of the East and the West is associated with the frequency content and duration of earthquakes. Earthquakes in the East are shorter with a higher frequency content.