Cross cracks in the brick wall of St Elmo Courts apartment block at the Hereford Street / Montreal Street intersection.
A damaged brick building on Tuam Street. Bricks have fallen from the wall exposing the interior, where a wooden structure can be seen to have collapsed. The photographer comments, "This is the damage caused by the numerous earthquakes in Christchurch, New Zealand. It closely resembles a face and the round blob in the square hole at the top of the nose is a pigeon".
A pigeon perches in the beams of a damaged building. The photographer comments, "The building next door was demolished after the Christchurch earthquake, which exposed the side of this building with it's very old corrugated iron walls. Some of the sheeting was damaged and exposed parts of the interior. The pigeon was sitting on a bit of wood with the beam above it had a very serious crack. I think you would be nervous as well".
A photograph of Siobhan Murphy outside her house at 436 Oxford Terrace. The front walls of the house have been covered with plastic sheeting. A bow made out of curtains has been pinned to the plastic where the fireplace juts out of the closest wall. The photographer comments, "The bow is a memorial to Murphy's living room and her life in the house".
Damage to The Bone Dude's Bone Carving Studio and Cultured Gallery on Fitzgerald Avenue. The brick wall is cracked, and the guttering has fallen. The photographer comments, "This building was damaged in the September earthquake in Christchurch. It was the Bone dude's bone carving studio. The motto on the wall was 'Carve your own' and it looks like the earthquakes did just that".
A building on St Asaph Street has been demolished, exposing the interior structure of the adjoining building. The photographer comments, "The building that this one was part of has been demolished and the join looks very much like the exterior walls of an Anglo-Saxon house. It has been exposed due to the demolition of damaged buildings after the Christchurch earthquake".
Based on the recent developments on alternative jointed ductile dry connections for concrete multistorey buildings, the paper aims to extend and propose similar innovative seismic connections for laminated veneer lumber (LVL) timber buildings. The dry connections herein proposed are characterised by a sort of rocking occurring at the section interface of the structural elements when an earthquake occurs; unbonded post-tensioned techniques and dissipative devices respectively provide self-centring and dissipation capacities. The paper illustrates some experimental investigations of an extensive campaign, still undergoing at the University of Canterbury Christchurch, NZ) are herein presented and critically discussed. In particular, results of cyclic quasi-static testing on exterior beam-column subassemblies and wall-to-foundation systems are herein presented; preliminary results of pseudo-dynamic testing on wall-to-foundation specimens are also illustrated. The research investigations confirmed the enhanced seismic performance of these systems/connections; three key aspects , as the no-damageability in the structural elements, typical “flag-shape” cyclic behaviour (with self-centring and dissipation capacity), negligible residual deformations, i.e. limited costs of repair, joined with low mass, flexibility of design and rapidity of construction LVL timber, all create the potential for an increased use in low-rise multistorey buildings.
A preliminary case study assessing the seismic sustainability of two reinforced concrete structures, a frame structure and a wall structure, was conducted to determine which structural system is more seismically sustainable. The two structures were designed to the same standards and were assumed to be located in Christchurch, New Zealand. A component-based probabilistic seismic loss assessment, considering direct losses only, was conducted for two ground motion records, regarded to approximately represent a 1 in 500 year earthquake event and a 1 in 2500 year earthquake event, respectively. It is shown that the wall structure results in lower direct losses than the frame structure in the less severe ground motion scenario. However, in the more severe ground motion scenario, the frame structure results in lower direct losses. Hence, this study demonstrates that which structural system has the lower direct losses depends on the ground motion intensity level.
Currently there is a worldwide renaissance in timber building design. At the University of Canterbury, new structural systems for commercial multistorey timber buildings have been under development since 2005. These systems incorporate large timber sections connected by high strength post-tensioning tendons, and timber-concrete composite floor systems, and aim to compete with existing structural systems in terms of cost, constructability, operational and seismic performance. The development of post-tensioned timber systems has created a need for improved lateral force design approaches for timber buildings. Current code provisions for seismic design are based on the strength of the structure, and do not adequately account for its deformation. Because timber buildings are often governed by deflection, rather than strength, this can lead to the exceedence of design displacement limitations imposed by New Zealand codes. Therefore, accurate modeling approaches which define both the strength and deformation of post-tensioned timber buildings are required. Furthermore, experimental testing is required to verify the accuracy of these models. This thesis focuses on the development and experimental verification of modeling approaches for the lateral force design of post-tensioned timber frame and wall buildings. The experimentation consisted of uni-direcitonal and bi-directional quasi-static earthquake simulation on a two-thirds scale, two-storey post-tensioned timber frame and wall building with timber-concrete composite floors. The building was subjected to lateral drifts of up to 3% and demonstrated excellent seismic performance, exhibiting little damage. The building was instrumented and analyzed, providing data for the calibration of analytical and numerical models. Analytical and numerical models were developed for frame, wall and floor systems that account for significant deformation components. The models predicted the strength of the structural systems for a given design performance level. The static responses predicted by the models were compared with both experimental data and finite element models to evaluate their accuracy. The frame, wall and floor models were then incorporated into an existing lateral force design procedure known as displacement-based design and used to design several frame and wall structural systems. Predictions of key engineering demand parameters, such as displacement, drift, interstorey shear, interstorey moment and floor accelerations, were compared with the results of dynamic time-history analysis. It was concluded that the numerical and analytical models, presented in this thesis, are a sound basis for determining the lateral response of post-tensioned timber buildings. However, future research is required to further verify and improve these prediction models.
A partially demolished building on Durham Street. The side wall has been demolished, exposing the inside space. A digger sits amongst the rubble.
An exposed brick wall left after the demolition of the adjoining building. The internal wooden structure and cabling can now be seen.
A photograph of the earthquake-damaged to 235 Kilmore Street. The building next door has been demolished, exposing the side wall.
A photograph of 291 and 293 Barbadoes Street. The front wall of the bottom storey has been boarded up with plywood.
A portaloo in Cranmer Square. In the background is a damaged property where the brick wall has crumbled, revealing the internal structures.
Earthquake damage to the Cranmer Centre. Bricks have fallen from the wall, exposing the inside rooms. Scaffolding has been placed around the building.
Detail of earthquake damage to the Cranmer Centre. Bricks have fallen from the wall, exposing the inside rooms. Wooden bracing supports the building.
Poster starting to peel off a corrugated wall next to demolition site. A section of damaged property can be seen above the fence.
A photograph of a window frame which has been removed from the Diabetes Centre and propped against the wall outside.
Damage to the Cranmer Courts. A section of the wall has crumbled, exposing the wooden framing and the interior of the building.
View down an alley between two buildings, where the brick wall on the left building has partially toppled, blocking the alley with rubble.
Earthquake damage to the Cranmer Centre. Bricks have fallen from the wall, exposing the inside rooms. Scaffolding has been placed around the building.
Earthquake damage to the dome of the Cathedral of the Blessed Sacrament. Stones have fallen from the wall supporting the dome.
Detail of damage around a property where the brick wall on the side of the building has crumbled, exposing the internal wooden structure.
Damage to the Bealey Denture Clinic. Some parts of the front wall have fallen off and the tiles on the roof are damaged.
Damage to a house, where the front wall has crumbled, revealing the timber framing. The fence around the house has also toppled over.
Detail of a section of the brick wall on the Weston House which has crumbled. Cordon fencing has been erected around the property.
Damage to the Cranmer Courts. A section of the wall has crumbled, exposing the wooden framing and the interior of the building.
A photograph of dancers performing in Stand Your Ground. A film is being projected onto the wall behind the dancers.
A photograph of volunteers standing beside a fence made from wooden pallets, at the site of the Poetica Urban Poetry wall.
A photograph of the Orzeit/Local Time exhibition. The photographs in the exhibition are displayed on the wall of a building.