		2006 NZSEE Conference
	Abstracts

Keynote Address Learning from Hawke's Bay 1931 Earthquake Performance Assessment and Retrofit Decision Making for Risk Mitigation Behaviour of Walls and Piers Understanding Reinforced Concrete Behaviour Modelling Earthquake Performance Earthquake Performance Poster Papers Design and Development

Preliminary Reconnaissance Report for the Kashmir Earthquake of 8 October 2005

Grant Dellow, Q. Ali, S.M. Ali, S. Hussain, B. Khazai and A. Nisar

A magnitude (M_w) 7.6 earthquake occurred at 8.55 am (local time) on 8 October 2005 causing extensive damage to buildings, bridges and roads and killing in excess of 87,000 people in the Kashmir region of northern Pakistan. Damage and deaths were also reported from Indian Administered Kashmir and eastern Afghanistan. The most severely affected region was in the epicentral area around Muzaffarabad in Pakistan Administered Kashmir. Reverse or thrust fault rupture on or near the Main Boundary Thrust of the Himalayas has been reported or observed from Chennari in the Jhelum River valley upstream of Muzaffarabad through to Muzaffarabad and over into the Kaghan valley as far north as Balakot, a distance of approximately 60 km. A notable feature of the effects of this earthquake was the asymmetric distribution of landslides across the fault rupture zone. On the downthrown or footwall side (to the southwest) landslide damage was relatively minor - the road from Manshera to Muzaffarabad was open to traffic within 8 hours of the earthquake and required the clearance of only one landslide. On the up-thrown or hanging wall side of the fault rupture zone (to the northeast) the road from Balakot to Kagan required the clearance of 253 landslides and took 24 days. These observations are consistent with the findings of recent strong motion studies.

Paper P31: [Read]

Assessment of the Potential for Earthquake Induced Lateral Spreading

Stuart Palmer

Lateral movement of reclamations and ground adjoining rivers and foreshores can occur as a result of earthquake shaking. The mechanism of this lateral movement is discussed and methods of analysis used are presented. Both empirical and mechanics based methods of analysis are used. Case studies of analysis and of construction works to mitigate the effects of lateral movement are presented. The mechanics based and empirical methods of analysis include simplifications and assumptions. It is concluded that any assessment of lateral movement potential should include as many methods of analysis as practical and include sensitivity checks on the assumed parameters. Ultimately, these methods provide support to engineering judgement to assess the likely performance of a site.

Paper P32: [Read]

Behaviour of Piles in Liquefied Deposits During Earthquakes

Misko Cubrinovski

Behaviour of piles in liquefied soils is discussed based on results of recent studies in Japan including (a) field performance and damage features of piles observed in the 1995 Kobe earthquake, (b) experimental findings from benchmark tests on full-size piles, and (c) simplified design methodology for piles undergoing lateral spreading. Particular attention is given to the effects of large lateral displacements of liquefied soils and their modelling in a simplified analysis of piles.

Paper P33: [Read]

Earthquake Risk Assessment of Flood Protection Assets in the Wellington Region

Alexei Murashev, Robert Davey, P. Brabhaharan and Beverley Curley

A study was undertaken to assess the earthquake risk to the Greater Wellington Regional Council flood protection assets in case of a major seismic event on the Wellington Fault. The vulnerability of various flood protection assets to seismic damage for Hutt, Otaki, Waikanae, Porirua, and Wainuiomata river flood protection schemes was assessed. The assets included 40 km of stopbanks, outlet structures, rock lines, block lines, groynes, flood walls, training banks, detention dams. Potential failure modes, extent of potential damage to the flood protection assets and the post-earthquake consequences for flood protection were considered. Requirements for and cost estimates of the reinstatement works to return the flood protection schemes to equivalent level of flood protection were developed. The study was carried out using a GIS platform, and this also facilitated presentation of maps showing the assessed damage states for the flood protection assets.

Paper P34: [Read]

Precast/prestressed Concrete Systems at Seismic Prone Area in Indonesia

Sugeng Wijanto

Precast/prestressed concrete construction methods are nowadays becoming more popular in Indonesia in conjunction with the rapid construction development. A large part of the Indonesian region is in a seismic prone area, therefore all building structures should be designed to accommodate gravity and also seismic loading. The design and implementation of the precast/prestressed system requires special attention, where no local official design guidelines exist yet.

This paper provides an overview of the development in the use of precast concrete systems in Indonesia and the application details of the connection system between the precast elements as well as between precast elements with the cast-in-place concrete structures. The connection system must be easily applicable and must not reduce the required detailing which is of primary importance in seismic prone areas.

Paper P35: [Read]

Soft First Story with Seismic Isolation System

A. Iqbal

A modified form of soft first story is proposed for multi-story structures with seismic isolation system at the top end of the story. The rest of the structure above and below the isolation level is designed to remain elastic while the isolation system provides the ductility and energy dissipation during an earthquake. Study of the behaviour of structures with such arrangements indicates that the soft first story provides effective protection against seismic forces while maintaining overall stability. The isolation system for the proposed concept consists of sliding bearings and steel dampers. It allows for relative displacements between the adjacent elements while reducing the force transmitted to the upper level. Energy is dissipated through yielding of the steel elements. A number of systems having different shapes and arrangements are considered here. The practical provisions and detailing requirements necessary for such arrangements are discussed.

Paper P36: [Read]