Search

found 109051 results

Images for [empty query]; more images...

Research papers, The University of Auckland Library

Micro - electro - mechanical system (MEMS) based accelerometers are now frequently used in many different parts of our day - to - day lives. It is also increasingly being used for structural testing applications. Researchers have had res ervation of using these devices as they are relatively untested, but now with the wider adoption, it provides a much cheaper and more versatile tool for structural engineering researchers. A number of damaged buildings in the Christchurch Central Business District (CBD) were instrumented with a number of low - cost MEMS accelerometers after the major Christchurch earthquakes. The accelerometers captured extremely high quality building response data as the buildings experienced thousands of aftershocks. This d ata set was amongst one of only a handful of data set s available around the world which provides building response data subjected to real ground motion. Furthermore, due to technological advances, a much larger than usual number of accelerometers has been deployed making the data set one of the most comprehensive available. This data set is utilised to extract modal parameters of the buildings. This paper summarises the operating requirements and preference for using such accelerometers for experimental mod al analysis. The challenges for adapting MEMS based devices for successful modal parameters identification are also discussed.

Research papers, The University of Auckland Library

The connections between walls of unreinforced masonry (URM) buildings and flexible timber diaphragms are critical building components that must perform adequately before desirable earthquake response of URM buildings may be achieved. Field observations made during the initial reconnaissance and the subsequent damage surveys of clay brick URM buildings following the 2010/2011 Canterbury, New Zealand earthquakes revealed numerous cases where anchor connections joining masonry walls or parapets with roof or floor diaphragms appeared to have failed prematurely. These observations were more frequent for adhesive anchor connections than for through-bolt connections (i.e. anchorages having plates on the exterior façade of the masonry walls). Subsequently, an in-field test program was undertaken in an attempt to evaluate the performance of adhesive anchor connections between unreinforced clay brick URM walls and roof or floor diaphragm. The study consisted of a total of almost 400 anchor tests conducted in eleven existing URM buildings located in Christchurch, Whanganui and Auckland. Specific objectives of the study included the identification of failure modes of adhesive anchors in existing URM walls and the influence of the following variables on anchor load-displacement response: adhesive type, strength of the masonry materials (brick and mortar), anchor embedment depth, anchor rod diameter, overburden level, anchor rod type, quality of installation and the use of metal mesh sleeve. In addition, the comparative performance of bent anchors (installed at an angle of minimum 22.5o to the perpendicular projection from the wall surface) and anchors positioned horizontally was investigated. Observations on the performance of wall-to-diaphragm connections in the 2010/2011 Canterbury earthquakes, a snapshot of the performed experimental program and the test results and a preliminary proposed pull-out capacity of adhesive anchors are presented herein. http://www.confer.co.nz/nzsee/ VoR - Version of Record

Research papers, The University of Auckland Library

Seismic retrofitting of unreinforced masonry buildings using posttensioning has been the topic of many recent experimental research projects. However, the performance of such retrofit designs in actual design level earthquakes has previously been poorly documented. In 1984 two stone masonry buildings within The Arts Centre of Christchurch received posttensioned seismic retrofits, which were subsequently subjected to design level seismic loads during the 2010/2011 Canterbury earthquake sequence. These 26 year old retrofits were part of a global scheme to strengthen and secure the historic building complex and were subject to considerable budgetary constraints. Given the limited resources available at the time of construction and the current degraded state of the steel posttension tendons, the posttensioned retrofits performed well in preventing major damage to the overall structure of the two buildings in the Canterbury earthquakes. When compared to other similar unretrofitted structures within The Arts Centre, it is demonstrated that the posttensioning significantly improved the in-plane and out-of-plane wall strength and the ability to limit residual wall displacements. The history of The Arts Centre buildings and the details of the Canterbury earthquakes is discussed, followed by examination of the performance of the posttension retrofits and the suitability of this technique for future retrofitting of other historic unreinforced masonry buildings. http://www.aees.org.au/downloads/conference-papers/

Images, eqnz.chch.2010

20140522_8951_EOS M-22 Demolition Of what many in Christchurch know as the Millers building, but for many recent years was the home to the Christchurch City Council, till just a week or two before the first earthquake of 2010. Now, in mid-2014 it is finally being demolished after nearly 45 months empty. A bus is leaving the new (temporary) bu...

Images, eqnz.chch.2010

20140521_1080_1D3-24 It has started! Removal of the double-glazed windows is underway at my "red zone" house, now owned by the Government of New Zealand. Sold to CERA (the government agency) in October 2012 and has remained empty since, despite having little damage, apart from the tilt to the front from the land damage that occurred during the...

Images, eqnz.chch.2010

A sight becoming more common in post-earthquake Christchurch - lifting earthquake-affected buildings to allow their foundations to be replaced and or completely replaced.

Images, eqnz.chch.2010

Overlooking McCormacks bay out across the city with the Southern Alps as a backdrop. There is still a strong effect from the July 11, 2011 Volcanic erruption (Puyehue) in Chile. Ash made it over to New Zealand causing very strong colours at sunset. The colours have not been artificially changed and its not a mash up. The parts of the city (and...

Images, eqnz.chch.2010

Another house has gone from Seabreeze Close, Pacific Park, Bexley, leaving just the concrete base, a few floor tiles and the smashed toilet (throne). Houses are being demolished (85%) or deconstructed/shifted (15%) as a result of land damage in the major earthquakes of 4th September 2010, 22nd February 2011, 13th June 2011 and 23rd December 2...

Images, eqnz.chch.2010

Christchurch's Graffiti House... This Cranford Street house was damaged in the earthquakes and is due for demolished this week but has been given a Graffiti Makeover by local Street Artists.

Images, eqnz.chch.2010

20140927_2219_1D3-24 Planting natives at Harold Henry Park A planting of native bushes and trees in the old children's playground area in Bexley, Organised by the Facebook group Avon River Park and assisted by ex Bexley residents. This is right in the middle of the Bexley red zone with most houses removed or demolished now. #5832

Images, eqnz.chch.2010

Today (04/09/14) marks the fourth anniversary since the first earthquake rocked the city and greater Christchurch area. That first quake was magnitude 7.1, and luckily there was only one fatality (possible a heart attack). Since then we have had over 14,000 quakes, most very small in magnitude, but well over 500 of magnitude 4 or greater. 5...

Images, eqnz.chch.2010

The sign reads: The CTV Building was headquarters of Canterbury Television (CTV) and also housed King’s Education language School, a medical clinic, Hair Consultants, Relationship Services and a nursing school. On February 22nd 2011 the building collapsed as a result of a major earthquake. Sadly, 115 people who were in the building lost their l...

Images, eqnz.chch.2010

On a walk over to Hagley Park to great some shots of the wonderful Cherry Blossom I past by the Knox Church rebuild and found that the scaffolding has come down at last. It sure was shinning in the midday light. Victoria Street September 12, 2014 Christchurch New Zealand

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.