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Research papers, The University of Auckland Library

During many years the analysis of some geophysical results of Charles Darwin was being carried out in Department. Darwin has connected almost 200 years ago results of catastrophic earthquakes with vertical movement of a surface of the Earth. Usually this movement less horizontal movement and its influence on destruction of cities is not considered. Earthquake hazard assessment studies were focused usually on the horizontal ground motion. Effects of the strong vertical motion were not, practically, discussed. The margins of safety against gravity-induced static vertical forces in constructed buildings usually provide adequate resistance to dynamic forces induced by the vertical acceleration during an earthquake. However, the earthquake in Christchurch is an example of the vertical seismic shock . The earthquake magnitude was rather small - nearby 6.3. However, the result was catastrophic. The same took place in 1835. It allowed to Darwin to formulate a few great ideas. Charles Darwin has explained qualitatively results of an interaction of huge seismic waves with volcanoes and the nature of volcanism and seismicity of our planet. These important data of Charles Darwin became very actual recently. It is possible to tell also the same about tsunami and extreme ocean waves described by Charles Darwin. Therefore this data were analyzed using modern mechanics, mathematics and physics in Department. In particular, the theory of catastrophic waves was developed based on Darwin's data. The theory tried to explain occurrence, evolution and distribution the catastrophic waves in various natural systems, since atoms, oceans, surfaces of the Earth and up to the very early Universe. Some results of the research were published in prestigious magazines. Later they were presented in two books devoted to Charles Darwin's anniversary (2009). Last from them was published in Russian (2011). We give here key ideas of this research which is a part of interdisciplinary researches of Department. Some ideas are discussed. Not less important purpose is very short historical review of some researches of Darwin. In particular, we underline Darwin' priority in the formulation of the bases of Dynamics Earth.

Research papers, The University of Auckland Library

The Canterbury earthquake sequence of 2010-2011 wrought ruptures in not only the physical landscape of Canterbury and Christchurch’s material form, but also in its social, economic, and political fabrics and the lives of Christchurch inhabitants. In the years that followed, the widespread demolition of the CBD that followed the earthquakes produced a bleak landscape of grey rubble punctuated by damaged, abandoned buildings. It was into this post-earthquake landscape that Gap Filler and other ‘transitional’ organisations inserted playful, creative, experimental projects to bring life and energy back into the CBD. This thesis examines those interventions and the development of the ‘Transitional Movement’ between July 2013 and June 2015 via the methods of walking interviews and participant observation. This critical period in Christchurch’s recovery serves as an example of what happens when do-it-yourself (DIY) urbanism is done at scale across the CBD and what urban experimentation can offer city-making. Through an understanding of space as produced, informed by Lefebvre’s thinking, I explore how these creative urban interventions manifested a different temporality to orthodox planning and demonstrate how the ‘soft’ politics of these interventions contain the potential for gentrification and also a more radical politics of the city, by creating an opening space for difference.

Research papers, The University of Auckland Library

The seismic tremor that shook Christchurch on February 22, 2011, not only shattered buildings but also the spirit of the city’s residents. Amidst the ruins, this design-focused thesis unravels two intertwining narratives, each essential to the city’s resurrection. At its core, this thesis probes the preservation of Christchurch’s memory and character, meticulously chronicling the lost heritage architecture and the subsequent urban metamorphosis. Beyond bricks and mortar, it also confronts the silent aftershocks - the pervasive mental health challenges stemming from personal losses and the disfigured cityscape. As a native of Christchurch, intimately connected to its fabric, my lens reflects not just on the architectural reconstruction but also on the emotional reconstruction. My experience as an autistic individual, a recently discovered facet of my identity, infuses this design journey with a distinct prism through which I perceive and interact with the world. The colourful sketches that drive the design process aren’t mere illustrations but manifestations of my interpretation of spaces and concepts, evoking joy and vitality—a testament to embracing diversity in design. Drawing parallels between healing my own traumas with my colourful and joyful neurodivergent worldview, I’ve woven this concept into proposals aimed at healing the city through whimsy, joy, and vibrant colours. Personal experiences during and post-earthquakes profoundly shape my design proposals. Having navigated the labyrinth of my own mental health amid the altered cityscape, I seek avenues for reconciliation, both personal and communal. The vibrant sketches and designs presented in this thesis encapsulate this vision—a fusion of vivid, unconventional interpretations and a dedication to preserving the essence of the original cityscape while still encouraging movement into the future.

Research papers, The University of Auckland Library

A review of the literature showed the lack of a truly effective damage avoidance solution for timber or hybrid timber moment resisting frames (MRFs). Full system damage avoidance selfcentring behaviour is difficult to achieve with existing systems due to damage to the floor slab caused by beam-elongation. A novel gravity rocking, self-centring beam-column joint with inherent and supplemental friction energy dissipation is proposed for low-medium rise buildings in all seismic zones where earthquake actions are greater than wind. Steel columns and timber beams are used in the hybrid MRF such that both the beam and column are continuous thus avoiding beam-elongation altogether. Corbels on the columns support the beams and generate resistance and self-centring through rocking under the influence of gravity. Supplemental friction sliders at the top of the beams resist sliding of the floor whilst dissipating energy as the floor lifts on the corbels and returns. 1:20 scale tests of 3-storey one-by-two bay building based on an earlier iteration of the proposed concept served as proof-of-concept and highlighted areas for improvement. A 1:5 scale 3-storey one-by-one bay building was subsequently designed. Sub-assembly tests of the beam-top asymmetric friction sliders demonstrated repeatable hysteresis. Quasi-static tests of the full building demonstrated a ‘flat bottomed’ flag-shaped hysteresis. Shake table tests to a suite of seven earthquakes scaled for Wellington with site soil type D to the serviceability limit state (SLS), ultimate limit state (ULS) and maximum credible event (MCE) intensity corresponding to an average return period of 25, 500 and 2500 years respectively were conducted. Additional earthquake records from the 22 February 2011 Christchurch earthquakes we included. A peak drift of 0.6%, 2.5% and 3.8% was reached for the worst SLS, ULS and MCE earthquake respectively whereas a peak drift of 4.5% was reached for the worst Christchurch record for tests in the plane of the MRF. Bi-directional tests were also conducted with the building oriented at 45 degrees on the shake table and the excitation factored by 1.41 to maintain the component in the direction of the MRF. Shear walls with friction slider hold-downs which reached similar drifts to the MRF were provided in the orthogonal direction. Similar peak drifts were reached by the MRF in the bi-directional tests, when the excitation was amplified as intended. The building self-centred with a maximum residual drift of 0.06% in the dynamic tests and demonstrated no significant damage. The member actions were magnified by up to 100% due to impact upon return of the floor after uplift when the peak drift reached 4.5%. Nonetheless, all of the members and connections remained essentially linearelastic. The shake table was able to produce a limited peak velocity of 0.275 m/s and this limited the severity of several of the ULS, MCE and Christchurch earthquakes, especially the near-field records with a large velocity pulse. The full earthquakes with uncapped velocity were simulated in a numerical model developed in SAP2000. The corbel supports were modelled with the friction isolator link element and the top sliders were modelled with a multi-linear plastic link element in parallel with a friction spring damper. The friction spring damper simulated the increase in resistance with increasing joint rotation and a near zero return stiffness, as exhibited by the 1:5 scale test building. A good match was achieved between the test quasi-static global force-displacement response and the numerical model, except a less flat unloading curve in the numerical model. The peak drift from the shake table tests also matched well. Simulations were also run for the full velocity earthquakes, including vertical ground acceleration and different floor imposed load scenarios. Excessive drift was predicted by the numerical model for the full velocity near-field earthquakes at the MCE intensity and a rubber stiffener for increasing the post joint-opening stiffness was found to limit the drift to 4.8%. Vertical ground acceleration had little effect on the global response. The system generates most of its lateral resistance from the floor weight, therefore increasing the floor imposed load increased the peak drift, but less than it would if the resistance of the system did not increase due to the additional floor load. A seismic design procedure was discussed under the framework of the existing direct displacement-based design method. An expression for calculating the area-based equivalent viscous damping (EVD) was derived and a conservative correction factor of 0.8 was suggested. A high EVD of up to about 15% can be achieved with the proposed system at high displacement ductility levels if the resistance of the top friction sliders is maximised without compromising reliable return of the floor after uplift. Uniform strength joints with an equal corbel length up the height of the building and similar inter-storey drifts result in minimal relative inter-floor uplift, except between the first floor and ground. Guidelines for detailing the joint for damage avoidance including bi-directional movement were also developed.