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This is the accepted version of the paper.This version of the publication may differ from the final published version. Abstract: The pressures exerted on the walls of rectangular planform steel flexible-walled silos by several different stored granular bulk solids are investigated using a validated finite element model that has been used in several previous studies. These pressures and the state of stress in the bulk solid are explored for a range of silo geometries and stored bulk solids. Permanent repository linkThe results show that the horizontal pressure distribution across a silo wall is generally not uniform. This demonstrates that widely used theories may be adequate for stiff concrete silos, are far from suited to flexible-walled steel silos, and the differences can be used to produce much lighter structures. These findings match previously published experimental and analytical results for square planform silos where much larger pressures develop in the corners. The present analyses show that rectangular silos differ from those of square section, in that the mean pressure and degree of pressure variation is different on the two walls. The mechanisms causing these changes are investigated. The results further demonstrate that relatively small changes in the properties of a stored solid can produce significant changes in the pressure magnitudes and patterns, and hence greatly influence the silo structural design.The paper concludes that existing design guidance is seriously deficient and leads to metal silos that are considerably more expensive than is necessary.ª Author to receive correspondence.2

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The rapid development of modern metropolises has led to a shortage of surface space and in response engineers have pursued alternatives below ground level. Shafts are commonly used to provide temporary access to the subsurface for tunnelling and, as permanent works, are utilised for lifts or ventilation purposes. The construction sequence of axisymmetric shafts makes them a dramatically simple solution. In addition, circular shafts are inherently stiffer than other plan geometries. Those, perhaps, are reasons why circular shafts are preferred in situations of restricted space or unfavourable ground conditions. However, due to the lack of case histories reporting ground movements induced by shaft construction, no empirical prediction method for subsurface soil displacements exists. The work presented here seeks to provide clearer insights into surface and subsurface soil displacements induced by circular shaft construction by means of analysis on measurements obtained from centrifuge tests and available field data. Novel empirical equations and procedures are suggested for practical use.

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