4 results for Allen, J.

  • Geotechnical & flooding reconnaissance of the 2014 March flood event post 2010-2011 Canterbury earthquake sequence, New Zealand. Report No. GEER035

    Allen, J.; Davis, C.; Giovinazzi, S.; Hart, D.E.; Cochrane, T.; Deam, B.; De Pascale, G.; Hicks, M.; Holland, D.; Hughes, M.; Johnson, L.; Ko, S.Y.; Measures, R.; Quigley, M.; Rix, G.; Siembieda, W.; Stark, N.; Teasley, R.; Wotherspoon, L.; van Ballegooy, S. (2014)

    Reports
    University of Canterbury Library

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  • Geotechnical aspects of the Mw6.2 2011 Christchurch New Zealand Earthquake

    Green, R.A.; Cubrinovski, M.; Wotherspoon, L.; Allen, J.; Bradley, B.A.; Bradshaw, A.; Bray, J.; DePascale, G.; Orense, R.; O’Rouke, T.; Pender, M.; Rix, G.; Wells, D.; Wood, C.; Henderson, D.; Hogan, L.; Kailey, P.; Robinson, K.; Taylor, M.; Winkley, A. (2012)

    Conference Contributions - Published
    University of Canterbury Library

    The 22 February 2011, Mw6.2 Christchurch earthquake is the most costly earthquake to affect New Zealand, causing an estimated 181 fatalities and severely damaging thousands of residential and commercial buildings. This paper presents a summary of some of the observations made by the NSF-sponsored GEER Team regarding the geotechnical/geologic aspects of this earthquake. The Team focused on documenting the occurrence and severity of liquefaction and lateral spreading, performance of building and bridge foundations, buried pipelines and levees, and significant rockfalls and landslides. Liquefaction was pervasive and caused extensive damage to residential properties, water and wastewater networks, high-rise buildings, and bridges. Entire neighborhoods subsided, resulting in flooding that caused further damage. Additionally, liquefaction and lateral spreading resulted in damage to bridges and to stretches of levees along the Waimakariri and Kaiapoi Rivers. Rockfalls and landslides in the Port Hills damaged several homes and caused several fatalities.

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  • Geotechnical Aspects of the 22 February 2011 Christchurch earthquake

    Cubrinovski, M.; Bradley, B.; Wotherspoon, L.; Green, R.; Bray, J.; Wood, C.; Pender, M.; Allen, J.; Bradshaw, A.; Rix, G.; Taylor, M.; Robinson, K.; Henderson, D.; Giorgini, S.; Ma, K.; Winkley, A.; Zupan, J.; O'Rourke, T.; DePascale, G.; Wells, D. (2011)

    Journal Articles
    University of Canterbury Library

    The 22 February 2011, Mw6.2-6.3 Christchurch earthquake is the most costly earthquake to affect New Zealand, causing 181 fatalities and severely damaging thousands of residential and commercial buildings, and most of the city lifelines and infrastructure. This manuscript presents an overview of observed geotechnical aspects of this earthquake as well as some of the completed and on-going research investigations. A unique aspect, which is particularly emphasized, is the severity and spatial extent of liquefaction occurring in native soils. Overall, both the spatial extent and severity of liquefaction in the city was greater than in the preceding 4th September 2010 Darfield earthquake, including numerous areas that liquefied in both events. Liquefaction and lateral spreading, variable over both large and short spatial scales, affected commercial structures in the Central Business District (CBD) in a variety of ways including: total and differential settlements and tilting; punching settlements of structures with shallow foundations; differential movements of components of complex structures; and interaction of adjacent structures via common foundation soils. Liquefaction was most severe in residential areas located to the east of the CBD as a result of stronger ground shaking due to the proximity to the causative fault, a high water table approximately 1m from the surface, and soils with composition and states of high susceptibility and potential for liquefaction. Total and differential settlements, and lateral movements, due to liquefaction and lateral spreading is estimated to have severely compromised 15,000 residential structures, the majority of which otherwise sustained only minor to moderate damage directly due to inertial loading from ground shaking. Liquefaction also had a profound effect on lifelines and other infrastructure, particularly bridge structures, and underground services. Minor damage was also observed at flood stop banks to the north of the city, which were more severely impacted in the 4th September 2010 Darfield earthquake. Due to the large high-frequency ground motion in the Port hills numerous rock falls and landslides also occurred, resulting in several fatalities and rendering some residential areas uninhabitable.

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  • Geotechnical reconnaissance of the 2010 Darfield (New Zealand) earthquake

    Cubrinovski, M.; Green, R.; Allen, J.; Ashford, S.; Bowman, E.; Bradley, B.A.; Cox, B.; Hutchinson, T.; Kavazanjian, E.; Orense, R.; Pender, M.; Quigley, M.; Wotherspoon, L. (2010)

    Reports
    University of Canterbury Library

    On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage occurred to unreinforced masonry buildings throughout the region during the mainshock and subsequent large aftershocks. Particularly extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, a geotechnical reconnaissance was conducted over a period of six days (10–15 September 2010) by a team of geotechnical/earthquake engineers and geologists from New Zealand and USA (GEER team: Geo-engineering Extreme Event Reconnaissance). JGS (Japanese Geotechnical Society) members from Japan also participated in the reconnaissance team from 13 to 15 September 2010. The NZ, GEER and JGS members worked as one team and shared resources, information and logistics in order to conduct thorough and most efficient reconnaissance covering a large area over a very limited time period. This report summarises the key evidence and findings from the reconnaissance.

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