Search

found 43 results

Images for reinforcement; more images...

Research papers, The University of Auckland Library

During the 2010/2011 Canterbury earthquakes, several reinforced concrete (RC) walls in multi-storey buildings formed a single crack in the plastic hinge region as opposed to distributed cracking. In several cases the crack width that was required to accommodate the inelastic displacement of the building resulted in fracture of the vertical reinforcing steel. This type of failure is characteristic of RC members with low reinforcement contents, where the area of reinforcing steel is insufficient to develop the tension force required to form secondary cracks in the surrounding concrete. The minimum vertical reinforcement in RC walls was increased in NZS 3101:2006 with the equation for the minimum vertical reinforcement in beams also adopted for walls, despite differences in reinforcement arrangement and loading. A series of moment-curvature analyses were conducted for an example RC wall based on the Gallery Apartments building in Christchurch. The analysis results indicated that even when the NZS 3101:2006 minimum vertical reinforcement limit was satisfied for a known concrete strength, the wall was still susceptible to sudden failure unless a significant axial load was applied. Additionally, current equations for minimum reinforcement based on a sectional analysis approach do not adequately address the issues related to crack control and distribution of inelastic deformations in ductile walls.

Images, UC QuakeStudies

The old Railway Station clock tower on Moorhouse Avenue with plywood and steel reinforcement covering two sides, a crane hanging over top. The brickwork suffered extensive cracking during the earthquake making it in need for reinforcement. The clock has stopped at around 16:35, the time of the earthquake.

Images, UC QuakeStudies

The old Railway Station clock tower on Moorhouse Avenue with plywood and steel reinforcement covering two sides, and a crane hanging over top. The brickwork suffered extensive cracking during the earthquake making it in need of reinforcement. The clock has stopped at around 16:35, the time of the earthquake.

Images, UC QuakeStudies

The old Railway Station clock tower on Moorhouse Avenue with plywood and steel reinforcement covering two sides, and a crane hanging over top. The brickwork suffered extensive cracking during the earthquake making it in need of reinforcement. The clock has stopped at around 16:35, the time of the earthquake.

Images, UC QuakeStudies

A photograph of a pile of twisted steel reinforcement and other rubble at the entrance to the Smiths City car park on Dundas Street. In the background a section of the collapsed car park has not been demolished yet. Many cars are still parked on the top floor.

Images, UC QuakeStudies

A photograph of the earthquake damage to the concrete beams in a room in the PricewaterhouseCoopers Building. Sections of the concrete have crumbled to reveal the steel reinforcement underneath. A number of the ceiling panels are missing and another is hanging loose. Some of the bars that hold the ceiling panels are also hanging loose.

Images, UC QuakeStudies

A photograph of the partially-demolished Smiths City car park, taken from Dundas Street. The front section of the car park has mostly been cleared, though there is still a scattering of rubble and steel reinforcement. The back section has collapsed, but the floors are largely intact, with many cars still parked on the top floor.

Images, UC QuakeStudies

A photograph looking east down Dundas Street. Piles of twisted steel reinforcement have been placed on both sides of the street. Several earthquake-damaged cars, recovered from the Smiths City car park, have been stacked on the left. On the other side of the street is an excavator grapple and bucket. In the distance two excavators are sorting through the rubble.

Images, UC QuakeStudies

A photograph of a flight of concrete stairs salvaged from a building and placed in a car park in the Christchurch central city. Steel reinforcement can be seen sticking out of the concrete.