Seismic Liquefaction Research by the University of Canterbury

Canterbury University research in seismic liquefaction is reviewed. The work discussed includes the development of a theoretical model for pore pressure increase as a function of earthquake magnitude and epicentral distance, together with the standard penetration value and initial effective overburden stress of the site soil. The model is based on the hypothesis that pore pressure increase is proportional to the density of seismic energy dissipated. Laboratory testing to examine the correctness of this hypothesis is described. Case histories of liquefaction in New Zealand have been catalogued, and field testing is being undertaken at some sites that liquefied during the 1968 Inangahua earthquake. The aim of the testing is both to add to the store of well-documented case histories, and to calibrate the theoretical model to local conditions. The feasibility of using Dutch cone testing (CPT) in place of the standard penetration test is also being investigated.