Hyder Consulting was a multi-national advisory and design consultancy with particular specialisation in the transport, property, utilities and environmental sectors. The firm employed approximately 4,200 people across the UK, Europe, Germany, Middle East, Asia and Australia and had been listed on the London Stock Exchange since October 2002. The name Hyder is the Welsh word for "confidence".In October 2014 it was acquired by Arcadis NV.
This paper deals with the application of cohesive zone models to study delamination failures in leg-angles of pultruded glass fibre reinforced polymer material using the general-purpose finite element software Abaqus. The objective of the study is to present a finite element modelling methodology that can, for example, help to fill-in knowledge gaps in the available experimental data pertaining to the tying force resistance of angle-cleated jointing in frame construction. It may be used to optimize cleat shape and laminate lay-up (dependent on composite processing method) for the strongest cleat against a minimum cost requirement. A benchmark example taken from literature is used to show that the numerical predictions from the authors' simulations are reliable. The approach is next used to analyse an equal leg-angle component where one leg is fixed and the other orthogonal leg is being deformed by a tensile force applied over the free end surface. Numerical results from Abaqus are used to show that a laminate produced by the pultrusion processing method fails unstably by delamination cracks radiating around the curved region and extending into the leg panels. As a preliminary study to show the potential of the new modelling methodology it is used to show the influence of the radius of curvature at the junction between the legs on the tying force resistance; based on the load at delamination onset a smaller radius reduces the cleat's strength.
From Photography to Photosynthesis In 1996, my interests as a passionate gardener and photo-based artist, that both dated from the 1970s, collided when I made the connection that plants are actually a form of photography; (photography from the Greek - meaning light drawing). Both photography and plants use the magical, mysterious ingredient that is LIGHT and the essential force that drives life on the planet.In fact, the largest photosensitive emulsion we know of is the planet earth. I draw inspiration and endless fascination from the awareness that the earth rotates in space and orbits the sun at a precise distance for the sun's radiation to affect the elegant process of photosynthesis through the myriad of plants that have evolved and grow on the planet. The earth is a three dimensional living photograph. The atmosphere and biosphere are also key factors that mediate the harshness of radiation bombarding the earth and nurture life on the planet that we know and depend upon. The process is an amazing thing and something we should revere and protect. Imagine the earth as a basket ball, wrapped in the thinnest paper you could find. The thickness of this delicate paper is equivalent to the atmosphere, and the depth of the paper's texture is thicker than the tallest trees, even thicker than the tallest high rise buildings!Image sequences from NASSA shows how vegetation grows, dies back, changes colour with the seasons, how the "photographic image" that is our planet alters. Increasingly human intervention plays a larger role in transforming the image of the globe we inhabit. Imagine foliated land as a photo-sensor (like in a digital camera)
The method of deriving the seismic design force in the current Australian bridge design code AS5100.2-2004 is force based and requires the use of a structural response factor R-f which is not defined for a structural system consisting of precast segmental concrete piers. There is an initiative to amend the current bridge design code to make it compatible with the changes made in AS1170.4-2007. The initiative also includes displacement based design method as an alternative to the current force based design method. This approach is new in the Australian design offices and there is a need to assess the impact these amendments will create. This paper details the workings of a performance based analysis to derive the seismic horizontal design force for the precast segmental concrete piers which meets the design requirements of the current bridge design code without using R-f. The effect of changes in AS1170.4-2007 and the outcome of implementing displacement based design method in the design of the precast pier have been discussed. The design feature of the Hunter Expressway viaducts which was developed to meet the requirements of AS5100.2-2004 is used to compare the effect of such proposed changes.
