168 research outputs found
Landslides in sensitive soils, Tauranga, New Zealand.
No full textIn the Tauranga region sensitive soil failures commonly occur after heavy rainfall events, causing considerable infrastructure damage. Several notable landslides include a large failure at Bramley Drive, Omokoroa in 1979, the Ruahihi Canal collapse in 1981, and numerous landslides in May 2005; recently the Bramley Drive scarp was reactivated in 2011. These failures are associated with materials loosely classified as the Pahoia Tephras - a mixture of rhyolitic pyroclastic deposits of approximately 1 Ma.
The common link with extreme rainfall events suggests a pore water pressure control on the initiation of these failures. Recent research on the structure of the soils shows a dominance of halloysite clay minerals packed loosely in arrangements with high porosity (51 – 77 %), but with almost entirely micropores. This leads us to conclude that the permeability is very low, and the materials remain continuously wet. The formation of halloysite is encouraged by a wet environment with no episodes of drying, supporting this assumption.
A high-resolution CPT trace at Bramley Drive indicates induced pore water pressures rising steadily to a peak at approximately 25 m depth; this depth coincides with the base of the landslide scarp. We infer that elevated pore water pressures develop within this single, thick aquifer, triggering failure through reduced effective stresses. The inactive halloysite clay mineral results in low plasticity indices (13 – 44 %) and hence high liquidity indices (1.2 – 2.4) due to the saturated pore space; remoulding following failure is sudden and dramatic and results in large debris runout distances
Sub-surface stratigraphy of Stella Passage, Tauranga Harbour.
No full textPort of Tauranga Ltd supported two initiatives designed to develop a greater understanding of the distribution of sediments below Stella Passage (Figure 1), particularly relating to areas that may require future dredging:
(1) As part of INTERCOAST PhD research by Ehsan Jorat, Port of Tauranga provided logistic support for a series of high-resolution Cone Penetration Test (CPT) soundings along a transect on the western margin of Stella Passage in February – March 2012;
(2) Port of Tauranga provided part-funding of a Summer Scholarship student (Amy Christophers) over the 2012/13 summer, particularly to look at pre-existing cores and core descriptions.
In addition, the University of Waikato undertook a series of sub-bottom seismic profile measurements in Stella Passage as part of a Summer Scholarship funded by the University over the 2012/13 summer.
This report summarises the current state of these investigations
First experience with carbon stripping foils for the 160 MeV H− injection into the CERN PSB
No full text160 MeV H beam will be delivered from the new CERN linear accelerator (Linac4) to the Proton Synchrotron Booster (PSB), using a H charge-exchange injection system. A carbon stripping foil will convert H into protons by stripping off the electrons. The H charge-exchange injection principle will be used for the first time in the CERN accelerator complex and involves many challenges. In order to gain experience with the foil changing mechanism and the very fragile foils, in 2016, prior to the installation in the PSB, a stripping foil test stand has been installed in the Linac4 transfer line. In addition, parts of the future PSB injection equipment are also temporarily installed in the Linac4 transfer line for tests with a 160 MeV H commissioning proton beam. This paper describes the foil changing mechanism and control system, summarizes the practical experience of gluing and handling these foils and reports on the first results with beam
Two static and vibratory Cone Penetration Tests in marine soils at Tauranga Harbor, New Zealand
No full textPiezovibrocones have been developed to evaluate the liquefaction potential of onshore soils, but have not yet been utilized to evaluate the in-situ liquefaction behavior of offshore marine and volcanoclastic sediments. Two static and vibratory CPTu (Cone Penetration Tests) were performed at Tauranga Harbor, New Zealand. The lithology is known from nearby drillholes and the influence of vibration on different types of marine soils is evaluated using the reduction ratio (RR) calculated from static and vibratory CPTu. A sediment layer with high potential for liquefaction and one with a slight reaction to cyclic loading are identified. In addition to the reduction ratio, the liquefaction potential of sediment is analyzed using classic correlations for static CPTu data, but no liquefaction potential was determined. This points to an underestimation of liquefaction potential with the classic static CPTu correlations in marine soil. Results show that piezovibrocone tests are a sensitive tool for liquefaction analysis in offshore marine and volcanoclastic soil
Building Sustainably with the Synergy of Traditional Craft and Modern Technology
No full textOur use of wood is broadly divided into two categories: wood for construction and wood for energy. This division arises not from the quality of the material but from our inability to adapt to its unpredictable properties. As a result, the Jorat forest alone burns around 3'000 m³ of wood every year. The Master Project proposes to find new ways to repurpose this wasted material for construction. By combining traditional craftsmanship with advanced digitalization, it aims to unlock the hidden potential of this wood. The project will create new production spaces focused on artisanal fields such as carpentry, cabin and tile making. These spaces will be established in the abandoned farms of the village of Ropraz, located in the northeast of the Jorat forest. They will use local wood to meet the growing demand for housing construction in the region. These activities will be part of the public space, forming a new wood-making village.CRCLGIS-G
Cone resistance, pore pressure, and vertical effective stress of CPT29a dredged area
No full textCone resistance, pore pressure, and vertical effective stress of CPT29b dredged are
Grenier norvegicum Gunnerus
No full textG. norvegicum Gunnerus Cat. 192 und 427. l: T^te du Geant (Briquet); Jorat (F.); Luisin (Zimmermann, Oberson); Van-Haut (F.); Col de la Golette (Favarger); La Tenda-Bel Oiseau (F.); Westhang der Arpille (F., Villaret). - 3: La Giete-Bovine südlich Martigny (F.); La Peula im Val Ferret (Melly); Charrat-Pierre ä Voir (idem); ob Eison gegen die Montagne d'Eison (Farquet und Maillefer); Zermatt (J.). - 3a: Laggintal (Hirschmann). - 4: Aletschwald (Schröter); Alpen von Fiesch (Wilczek); Binntal, mehrfach (Binz, Becherer); Rappental (B. C. W.); Blindental (B. C. W.). Forma viride Vaccari et Melly (1909) (G. norv. var. viridescens Legrand, G. norv. f. viridescens Braun-Blanquet [1917], Briq. et Cavill. [1917]) - 3: Unter den Lacs de Fenetre (Val Ferret); bei Bourg-St-Pierre und LaPierraz im Val d'Entremont (alles:Melly).Published as part of Becherer, 1956, Florae Vallesiacae Supplementum, pp. 1-556 in Denkschriften der Schweizerischen Naturforschenden Gesellschaft 71 on pages 1-55
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