A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
With the dawn of a new year (yes, we know it’s already April May June July, no we are not accepting constructive criticism at this time) the Under Over team has hit the ground running. The dream of a leisurely … Continue reading →
A photograph of steel bracing keeping up a section of the ceiling on the ground floor of the Crowne Plaza. The column to the left is damaged.
St John's Anglican Church in Hororata. The top of the bell tower has collapsed into the roof of the church, some falling onto the ground below where it still lies.
St John's Anglican Church in Hororata. The top of the bell tower has collapsed into the roof of the church, some falling onto the ground below where it still lies.
A photograph of a peice of masonry which has been removed from the roof of St John the Baptist Church and placed on the ground outside.
A photograph of a peice of masonry which has been removed from the roof of St John the Baptist Church and placed on the ground outside.
A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
A felt heart sewn to the wire fencing in front of the Ground Culinary Centre in Lyttelton. The heart provides a bit of beauty and hope to an otherwise depressing scene, with the word "Love" embroided in the centre.
The stitching of felt hearts on the anniversary of the first earthquake on the site of the demolished Ground Culinary Centre, which is now the Lyttelton Petanque Club grounds, a gathering spot for many community events and activities.
Photograph captioned by BeckerFraserPhotos, "The cleared site of Ground, corner on London and Canterbury Streets, Lyttelton. A rest area and garden sales have developed here".
A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
A photograph of the east side of the Odeon Theatre, showing the severe damage at the back of the theatre. Part of the roof sits on the ground in the section next door.
A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
A photograph of a detail of a finial from the top of one of the spires of the Cranmer Centre, removed and placed on the ground in front.
Damage to the St John the Baptist church hall in Latimer Square, seen behind the cordon fence. On the ground next to some building rubble is a sign that says 'Danger!!! Wall unstable. Stay clear'.
The ground floor of the BNZ Building, seen from High Street. The glass has been removed and the insides gutted. The Cathedral can be viewed through the other side.
The top of one of the towers from the Arts Centre has been placed on the ground to prevent further damage. The photographer comments, "A bike ride around the CBD. Arts Centre".
Damage to the St John the Baptist church hall in Latimer Square, seen behind the cordon fence. On the ground next to some building rubble is a sign that says 'Danger!!! Wall unstable. Stay clear'.
A photograph captioned by BeckerFraserPhotos, "Workers deconstructing the Hotel Grand Chancellor. Panels are being detached and the crane is lowering them to the ground".
Photograph captioned by BeckerFraserPhotos, "At the end of the day, these workers on the Hotel Grand Chancellor take a ride back to the ground".
A view that was impossible six years ago. There was a group of buildings including another high-rise in the vacant area in the middle ground.
Following the Mw 6.2 Christchurch Earthquake on 22 February 2011, extensive ground cracking in loessial soils was reported in some areas of the Port Hills, southeast of central Christchurch. This study was undertaken to investigate the mechanisms of earthquake-induced ground damage on the eastern side of the Hillsborough Valley. A zone of extensional cracking up to 40m wide and 600m long was identified along the eastern foot-slope, accompanied by compression features and spring formation at the toe of the slope. An engineering geological and geomorphological model was developed for the eastern Hillsborough Valley that incorporates geotechnical investigation data sourced from the Canterbury Geotechnical Database (CGD), the findings of trenching and seismic refraction surveying carried out for this research, and interpretation of historical aerial photographs. The thickness and extent of a buried peat swamp at the base of the slope was mapped, and found to coincide with significant compression features. Ground cracking was found to have occurred entirely within loess-colluvium and to follow the apices of pre-1920s tunnel-gully fan debris at the southern end of the valley. The ground-cracking on the eastern side of the Hillsborough Valley is interpreted to have formed through tensile failure of the loess-colluvium. Testing was carried out to determine the tensile strength of Port Hills loess colluvium as a function of water content and density, in order to better understand the occurrence and distribution of the observed ground cracking. A comprehensive review of the soil tensile strength testing literature was undertaken, from which a test methodology was developed. Results show remoulded loess-colluvium to possess tensile strength of 7 - 28 kPa across the range of tested moisture contents (10-15%) and dry densities (1650-1900kg/m3). A positive linear relationship was observed between tensile strength and dry density, and a negative linear relationship between moisture content and tensile strength. The observed ground damage and available geotechnical information (inclinometer and piezometer records provided by the Earthquake Commission) were together used to interpret the mechanism(s) of slope movement that occurred in the eastern Hillsborough Valley. The observed ground damage is characteristic of translational movement, but without the development of lateral release scarps, or a basal sliding surface - which was not located during drilling. It is hypothesised that shear displacement has been accommodated by multiple slip surfaces of limited extent within the upper 10m of the slope. Movement has likely occurred within near-saturated colluvial units that have lost strength during earthquake shaking. The eastern Hillsborough Valley is considered to be an ‘incipient translational slide’, as both the patterns of damage and shearing are consistent with the early stages of such slide development. Sliding block analysis was utilised to understand how the eastern Hillsborough Valley may perform in a future large magnitude earthquake. Known cumulative displacements of ~0.3m for eastern Hillsborough Valley during the 2010-2011 Canterbury Earthquake Sequence were compared with modelled slope displacements to back-analyse a lower-bound yield acceleration of 0.2 - 0.25g. Synthetic broadband modelling for future Alpine and Hope Fault earthquakes indicates PGAs of approximately 0.08g for soil sites in the Christchurch area, as such, slope movement is unlikely to be reactivated by an Alpine Fault or Hope Fault earthquake. This does not take into account the possible role of strength loss due to excess pore pressure that may occur during these future events.
Sandbags placed along the river bank to prevent flooding onto the road. The earthquake caused the ground in this area to subside, making it susceptible to flooding.
Sandbags placed along the river bank to prevent flooding onto the road. The earthquake caused the ground in this area to subside , making it susceptible to flooding.
We present initial results from a set of three-dimensional (3D) deterministic earthquake ground motion simulations for the northern Canterbury plains, Christchurch and the Banks Peninsula region, which explicitly incorporate the effects of the surface topography. The simu-lations are done using Hercules, an octree-based finite-element parallel software for solving 3D seismic wave propagation problems in heterogeneous media under kinematic faulting. We describe the efforts undertaken to couple Hercules with the South Island Velocity Model (SIVM), which included changes to the SIVM code in order to allow for single repetitive que-ries and thus achieve a seamless finite-element meshing process within the end-to-end ap-proach adopted in Hercules. We present our selection of the region of interest, which corre-sponds to an area of about 120 km × 120 km, with the 3D model reaching a depth of 60 km. Initial simulation parameters are set for relatively high minimum shear wave velocity and a low maximum frequency, which we are progressively scaling up as computing resources permit. While the effects of topography are typically more important at higher frequencies and low seismic velocities, even at this initial stage of our efforts (with a maximum of 2 Hz and a mini-mum of 500 m/s), it is possible to observe the importance of the topography in the response of some key locations within our model. To highlight these effects we compare the results of the 3D topographic model with respect to those of a flat (squashed) 3D model. We draw rele-vant conclusions from the study of topographic effects during earthquakes for this region and describe our plans for future work.
An abandoned residential property at 37 Seabreeze Close in Bexley. Weeds are growing through the cracks in the ground and the yard has become overgrown. The garage door has been vandalised with graffiti.
Damage to the bell tower of St Luke's Church on Manchester Street. The stones have crumbled and are lying on the ground where they fell. Damage can also be seen on the roof.
An aerial photograph captioned by BeckerFraserPhotos, "Scarborough cliffs showing the massive rock fall on 13 June. The red roof house (right) above the rock tongue poking into the sea, lost 25m of ground during the fall".