USGS Award Number G16AP00003 REDUCING UNCERTAINTY OF LIQUEFACTION HAZARD ASSESSMENTS IN AGED SOIL DEPOSITS Final Report to the United States Geological Survey By: Barnabas Bwambale and Ronald D. Andrus Glenn Department of Civil Engineering Clemson University Lowry Hall, Box 340911 Clemson, South Carolina 29634-0911 USA Telephone: (864) 656-0488 Fax: (864) 656-2670 E-mail:
[email protected] February 18, 2017 Research supported by the United States Geological Survey (USGS), Department of the Interior, under USGS award number G16AP00003. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Geological Survey. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey. ii USGS Award Number G16AP00003 REDUCING UNCERTAINTY OF LIQUEFACTION HAZARD ASSESSMENTS IN AGED SOIL DEPOSITS Final Report to the United States Geological Survey by Barnabas Bwambale and Ronald D. Andrus Glenn Department of Civil Engineering Clemson University Lowry Hall, Box 340911 Clemson, South Carolina 29634-0911 USA Telephone: (864) 656-0488 Fax: (864) 656-2670 E-mail:
[email protected] ABSTRACT The influence of aging processes (or simply age) on liquefaction resistance of Holocene and Pleistocene soils near Christchurch, New Zealand is evaluated in this report. Many Holocene alluvial and marine deposits in and around Christchurch experienced minor to severe liquefaction during the 2010-2011 Canterbury earthquake sequence. Liquefaction and permanent ground deformations were most severe in the city during the 22 February 2011 event. Permanent horizontal ground displacements up to 0.35 m also occurred at several locations in moderately sloping Pleistocene loess-colluvium in the Port Hills area, but no sand/silt boil has been connected to those deposits.