Abstract Routine effective stress analyses for failure of geotechnical structures use a linear Mohr-Coulomb envelope and routine analyses for ground movements use linear elasticity with constant Young’s Modulus E’ or one-dimensional modulus M’. Observations of soil behaviour show that strength and stiffness are non-linear and…
Abstract Until 2017 there was no standard template in New Zealand to assist in the specification and procurement of ground investigations, and so consequently specifications varied significantly from project to project and between organisations. This caused numerous problems: (1) Long project specific specifications were unlikely…
Abstract Currently, there is an increasing interest in providing more sustainable solutions for mitigating liquefaction and interdisciplinary work has started to introduce the use of nano-materials for this purpose. These materials have some advantages when compared with traditional techniques. For instance, they could be injected…
Abstract One of the Canterbury Earthquake Royal Commission recommendations was that “ground improvement should be considered as part of the foundation system of a building and reliability factors included in the design procedures” and that “the Ministry of Business, Innovation and Employment should consider the…
The new Gisborne Police Station building was built on a soft site occupied by a historical retail building. The façade of the historical building had to be retained, and the building demolished. Based on complex geotechnical investigations and consideration of various foundation options, Opus recommended that a piled…
Abstract It is recognised that earthquake design of high cut slopes in hilly to mountainous terrain is important to ensure that the next generation of transportation routes have adequate resilience to provide access to communities following an earthquake event. There is very little guidance in…
Abstract Assessment and mitigation of potential liquefaction is a critical requirement for successful infrastructure design in seismically active regions of New Zealand. This paper highlights several important lessons learnt from the design and construction of ground improvements to mitigate the effects of liquefaction on the…
Abstract Acid Sulphate Soils have recently been encountered on projects in Whangarei and Auckland. These naturally occurring soils are rich in sulphide minerals that have the potential to cause changes in soil and water chemistry when they oxidise. This oxidation process occurs naturally but may…
Abstract Water ingress into a mined tunnel can be an issue – not just for construction but also for depressurisation and the potential consequential surface settlement. The Waterview Connection in Auckland has twin ~14.5m diameter TBM tunnels linked by 16 mined cross passages. Each cross…
Abstract Accurate, high-resolution topographic models are fundamentally important for detailed engineering geological mapping. Nevertheless, high economic costs of topographic data collection are often exacerbated by remoteness of field sites, rendering cheaper, more portable surveying platforms (i.e. terrestrial laser scanning or GPS) impractical. An alternative is…