Search
found 524 results
Images for Concrete; more images...
Seismic design of reinforced concrete beam-column joints with floor slab
Research papers, University of Canterbury Library
Beam-column joints are addressed in the context of current design procedures and performance criteria for reinforced concrete ductile frames subjected to large earthquake motions. Attention is drawn to the significant differences between the pertinent requirements of concrete design codes of New Zealand and the United States for such joints. The difference between codes stimulated researchers and structural engineers of the United States, New Zealand, Japan and China to undertake an international collaborative research project. The major investigators of the project selected issues and set guidelines for co-ordinated testing of joint specimens designed according to the codes of the countries. The tests conducted at the University of Canterbury, New Zealand, are reported. Three full-scale beam-column-slab joint assemblies were designed according to existing code requirements of NZS 3101:1982, representing an interior joint of a one-way frame, an interior joint of a two-way frame, and an exterior joint of a two-way frame. Quasistatic cyclic loading simulating severe earthquake actions was applied. The overall performance of each test assembly was found to be satisfactory in terms of stiffness, strength and ductility. The joint and column remained essentially undamaged while plastic hinges formed in the beams. The weak beam-strong column behaviour sought in the design, desirable in tall ductile frames designed for earthquake resistance, was therefore achieved. Using the laws of statics and test observations, the action and flow of forces from the slabs, beams and column to the joint cores are explored. The effects of bond performance and the seismic shear resistance of the joints, based on some postulated mechanisms, are examined. Implications of the test results on code specifications are discussed and design recomendations are made.
Research Programme on Seismic Performance of Reinforced Concrete Walls: Ke…
Research papers, University of Canterbury Library
A wide range of reinforced concrete (RC) wall performance was observed following the 2010/2011 Canterbury earthquakes, with most walls performing as expected, but some exhibiting undesirable and unexpected damage and failure characteristics. A comprehensive research programme, funded by the Building Performance Branch of the New Zealand Ministry of Business, Innovation and Employment, and involving both numerical and experimental studies, was developed to investigate the unexpected damage observed in the earthquakes and provide recommendations for the design and assessment procedures for RC walls. In particular, the studies focused on the performance of lightly reinforced walls; precast walls and connections; ductile walls; walls subjected to bi-directional loading; and walls prone to out-of-plane instability. This paper summarises each research programme and provides practical recommendations for the design and assessment of RC walls based on key findings, including recommended changes to NZS 3101 and the NZ Seismic Assessment Guidelines.
Evaluation of simplified seismic vulnerability assessment procedures for r…
Research papers, University of Canterbury Library
The need for a simple but rigorous seismic assessment procedure to predict damage to reinforced concrete buildings during a seismic event has been highlighted following the Canterbury Earthquake sequence. Such simplified assessment procedure, applied to individual structure or large building inventory, should not only have low requirement in terms of input information and involve straightforward analyses, but also should be capable to provide reliable predictive results within short timeframe. This research provides a general overview and critical comparison of alternative simplified assessment procedures adopted in NZSEE 2006 Guidelines (Assessment and Improvement of the Structural Performance of Buildings in Earthquakes), ASCE 41-13 (Seismic Evaluation and Retrofit of Existing Buildings), and EN: 1998-3: 2005 (Assessment and Retrofitting of Buildings). Particular focus is given to the evaluation of the capability of Simplified Lateral Mechanism Analysis (SLaMa), which is an analytical pushover method adopted in NZSEE 2006 Guidelines. The predictive results from SLaMa are compared to damages observed for a set of reinforced concrete buildings in Christchurch, as well as the results from more detailed assessment procedure based on numerical modelling. This research also suggests improvements to SLaMa, together with validation of the improvements, to include assessment of local mechanism by strength hierarchy evaluation, as well as to develop assessment of global mechanism including post-yield mechanism sequence based on local mechanism.
BeckerFraserPhotos February 2012 photograph 0171
Images, UC QuakeStudies
A photograph of a train painted on a concrete block in a retaining wall, alongside the words, "The gravy train". The photograph is captioned by BeckerFraserPhotos, "Cunningham Terrace, Lyttelton".
BeckerFraserPhotos February 2012 photograph 0176
Images, UC QuakeStudies
A photograph of an opera singer singing the words "Cera, cera", painted on a concrete block in a retaining wall. The photograph is captioned by BeckerFraserPhotos, "Cunningham Terrace, Lyttelton".
Paul and Sam Corliss's Street Art Photograph (2015:03:27 12:52:56)
Images, UC QuakeStudies
A photograph of a tag on a wall made of concrete blocks. The wall is near the railway tracks which run under the Durham Street over bridge. The tag reads, "JFK".
BeckerFraserPhotos December 2011 photograph 1971
Images, UC QuakeStudies
A photograph captioned by BeckerFraserPhotos, "A concrete-block wall from a building on the corner of Colombo and Gloucester Streets which has fallen in an interesting pattern during demolition".
Grand Chancellor Lean
Images, eqnz.chch.2010
Hotel Grand Chancellor on verge of collapse but still standing after the 6.3 magnitude quake hit Christchurch on 22 February 2011 because of concrete being poured into the lower floors.
Effect of precast-prestressed flooring systems on the seismic performance …
Research papers, University of Canterbury Library
A one story, two bays, approximately half scaled, perimeter moment frame containing precastprestressed floor units was built and tested at the University of Canterbury to investigate the effect of precastprestressed floor units on the seismic performance of reinforced concrete moment resisting frame. This paper gives an overview of the experimental set up and summarizes the results obtained from the test. The results show that elongation in the beam plastic hinges is partially restrained by the prestressed floor, which increases the strength of the beams much more than that being specified in the codes around the world.
BeckerFraserPhotos February 2012 photograph 0169
Images, UC QuakeStudies
A photograph of a house with retaining walls supported by large bags of concrete. The photograph is captioned by BeckerFraserPhotos, "On the corner of Ticehurst Road and Bridle Path, Lyttelton".
The Earthquake Worms
Images, UC QuakeStudies
A digitally manipulated photograph of twisted reinforcing rods amongst the rubble from the demolition of QEII. The photographer comments, "These rarely seen worms live in the pressurised earth under the foundations of buildings. They need a damp soil and be under at least 100 pounds of pressure per square inch. After the destructive force of an earthquake they swiftly rise to the surface through gaps in the rubble. Unfortunately they quickly die and then crystallise as hard as iron in the dry low pressure air".
Crack'd for Christchurch Photograph 113
Images, UC QuakeStudies
A photograph of members of Crack'd for Christchurch polishing the flower mosaics on their armchair artwork.Crack'd for Christchurch comments, "From left: Jennie Cooper, Helen Campbell, and Jenny Cooper."
BeckerFraserPhotos May 2013 photograph 173
Images, UC QuakeStudies
A temporary retaining wall on Sumner Road in Lyttelton. The concrete moulds for the wall are filled with rocks and stones. Black tarpaulins have been placed over the top section of the wall.
Umut Akguzel Photograph 367
Images, UC QuakeStudies
A photograph of the badly-damaged Winnie Bagoes building on Colombo Street. The left side of the building has collapsed and a metal pole anchored to a concrete block is holding up the remains.
Bettina Evans's photograph 100
Images, UC QuakeStudies
Patchwork quilts wrapped around the concrete slabs used to stabilise a broken wall on Winchester Street. They make it look snug despite the snow. Many projects like this have cropped up around Canterbury in an effort to brighten the earthquake environment.
Umut Akguzel Photograph 366
Images, UC QuakeStudies
A photograph of the badly-damaged Winnie Bagoes building on Colombo Street. The left side of the building has collapsed and a metal pole anchored to a concrete block is holding up the remains.
BeckerFraserPhotos July 2011 photograph 1316
Images, UC QuakeStudies
A photograph captioned by BeckerFraserPhotos, "Victoria Street. A giant vibrating pair of nibblers makes easy work of demolishing a reinforced concrete building. This section of wall was reduced to rubble in about two minutes".
BeckerFraserPhotos April 2011 photograph 015
Images, UC QuakeStudies
Plastic barriers and fencing around a demolition site on the corner of Cranford and Westminster Streets. Different types of building rubble have been sorted into piles, and a concrete block still remains on-site.
BeckerFraserPhotos February 2011 photograph 340
Images, UC QuakeStudies
Two damaged driveways on Acland Avenue in Avonside. Dried liquefaction can be seen in the gap between the two driveways, and behind them the ground has sunk. Weeds have grown through cracks in the concrete.
BeckerFraserPhotos October 2011 photograph 356
Images, UC QuakeStudies
Photograph captioned by BeckerFraserPhotos, "Demolition site of Allan McLean building, corner of Colombo Street and Oxford Terrace".
BeckerFraserPhotos February 2011 photograph 339
Images, UC QuakeStudies
Two damaged driveways on Acland Avenue in Avonside. Dried liquefaction can be seen in the gap between the two driveways, and behind them the ground has sunk. Weeds have grown through cracks in the concrete.
Photograph of Gap Filler project 22 (12)
Images, UC QuakeStudies
The partially constructed Pallet Pavilion on the site of the demolished Crowne Plaza Hotel. Concrete slabs have been laid on the ground and a stack of painted pallets can be seen in the background.
Photograph by Jocelyn Kinghorn 2391
Images, UC QuakeStudies
Damage to the Cathedral of the Blessed Sacrament. Looking through the fence on to the side and front where shipping containers are being used to support the walls, with a pile of concrete blocks next to the cathedral.
Crack'd for Christchurch Photograph 112
Images, UC QuakeStudies
A photograph of Marie Hudson attaching a flower mosaic to Crack'd for Christchurch's armchair artwork.Crack'd for Christchurch comments, "Marie makes it look easy."
Crack'd for Christchurch Photograph 111
Images, UC QuakeStudies
A photograph of Marie Hudson attaching a flower mosaic to Crack'd for Christchurch's armchair artwork.Crack'd for Christchurch comments, "Marie makes it look easy."
BeckerFraserPhotos February 2011 photograph 268
Images, UC QuakeStudies
A view down Bracken Street in Avonside. A power pole has been propped up by a concrete block because the asphalt around it has sunk as a result of the 4 September 2010 earthquake.
BeckerFraserPhotos June 2011 photograph 370
Images, UC QuakeStudies
Damage to a house in Redcliffs. There are large cracks in the concrete block walls and several blocks have fallen. The chimney is still intact, but is leaning away from the house at an extreme angle.
BeckerFraserPhotos June 2011 photograph 371
Images, UC QuakeStudies
Damage to a house in Redcliffs. There are large cracks in the concrete block walls and several blocks have fallen. The chimney is still intact, but is leaning away from the house at an extreme angle.
BeckerFraserPhotos February 2011 photograph 405
Images, UC QuakeStudies
A view down the driveway of a property on Avonside Drive to its garage. The slabs of concrete that make up the driveway have all visibly shifted, and the garage is on a lean.
Photograph by Neil Macbeth 357
Images, UC QuakeStudies
Damage to a bridge over the Avon River in Avonside. The bridge has pulled away from the bank, leaving large cracks between the concrete sides and the ground. The railing has also separated to the left.