Tunnelling 94

It is now more than twenty years since a proposal was first mooted to hold an international tunnelling symposium in Britain. At the time of the first symposium, held in London in 1976, the Channel Tunnel pro ject had just been shelved. Last weekend a charity walk was held in the finished tunnel, which will be open for business later in the year. Tunnels have figured prominently, and at times spectacularly, in the development of national and international links and it is hoped that such links gather pace in the future. It is particularly pleasing that Alastair Biggart of Storebrelt has agreed to deliver the twenty-sixth Sir Julius Wernher Memorial Lecture of the Institution of Mining and Metallurgy, entitled 'The changing face of tunnelling', at the start of this event. * Although almost every edition of the technical journals on tunnelling reports another £1 billion scheme somewhere in the world, it would be unfair of me to suggest that tunnelling is restricted to these prestigious schemes for major transport links. Much of the work that makes mod ern life possible receives hardly a mention outside the technical press and one suspects that society at large applies the 'out of sight, out of mind' attitude even more readily to underground construction than it does to other forms of engineering. Clearly, there is a contiiming need to improve the capacity and performance of our infrastructure, while hav ing a careful regard for the environment.

Based on a three day conference held in London on 5-7th July 1994. The theme is the design and construction of tunnels in the fields of civil and mining engineering worldwide, with a sub-theme of environmental issues.

This practical guide describes the stage-by-stage development of a method for predicting the penetration rate (PR) and the advance rate (AR) for tunnel boring machines based on an expanded version of the Q-value, QTBM. The author analyzes 145 TBM tunnels that total 1,000km in length. He then develops simple formulae to estimate PR and AR from the QTBM value and to back-calculate QTBM from performance data. The book quantitatively explains actual advance rates as high as five m/hr for one day or as low as 0.005 m/hr for several months. It also covers logging methods, empirical TBM tunnel support design, and numerical verification of support.

This guide considers the implications of the use of sprayed concrete support methods in soft ground in urban areas and provides guidance on how the associated risks of this method can be minimised.

Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art contains the contributions presented at the World Tunnel Congress 2019 (Naples, Italy, 3-9 May 2019). The use of underground space is continuing to grow, due to global urbanization, public demand for efficient transportation, and energy saving, production and distribution. The growing need for space at ground level, along with its continuous value increase and the challenges of energy saving and achieving sustainable development objectives, demand greater and better use of the underground space to ensure that it supports sustainable, resilient and more liveable cities. This vision was the source of inspiration for the design of the logos of both the International (ITA) and Italian (SIG) Tunnelling Association. By placing key infrastructures underground – the black circle in the logos – it will be possible to preserve and enhance the quality of the space at ground level – the green line. In order to consider and value underground space usage together with human and social needs, engineers, architects, and artists will have to learn to collaborate and develop an interdisciplinary design approach that addresses functionality, safety, aesthetics and quality of life, and adaptability to future and varied functions. The 700 contributions cover a wide range of topics, from more traditional subjects connected to technical challenges of design and construction of underground works, with emphasis on innovation in tunneling engineering, to less conventional and archetypically Italian themes such as archaeology, architecture, and art. The book has the following main themes: Archaeology, Architecture and Art in underground construction; Environment sustainability in underground construction; Geological and geotechnical knowledge and requirements for project implementation; Ground improvement in underground constructions; Innovation in underground engineering, materials and equipment; Long and deep tunnels; Public communication and awareness; Risk management, contracts and financial aspects; Safety in underground construction; Strategic use of underground space for resilient cities; Urban tunnels. Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art is a valuable reference text for tunneling specialists, owners, engineers, architects and others involved in underground planning, design and building around the world, and for academics who are interested in underground constructions and geotechnics.

Internationally, the mechanized excavation of tunnels has intensified in the last two decades, as the number of tunnels being constructed for subways and railway underpasses increases. The subject of mechanized tunnelling in urban areas has not previously received the attention that it deserves, despite there being specific hazards associated with the construction of tunnels in metropolitan areas, including poor ground conditions, water tables higher than the level of tunnels, and subsidence leading to damage to the existing structures on the surface. The application of technologies for achieving the stability of the tunnel and for minimizing surface settlement is described in this book. Accurate characterization of the ground; rigorous assessment and management of risk from design to maintenance; the correct choice of a tunnel boring machine and a plan for the advancement of the tunnel; specific excavation procedures and real-time monitoring of excavation parameters are all discussed in this thorough work.

The ability to predict the potential damage to buildings accurately and to have confidence in the chosen protective measures is of increasing importance for the viability of urban tunnelling. The Jubilee Line Extension Project (JLEP) presented a unique opportunity to capture reliable field measurements of the effects of tunnelling on a wide range of buildings. Building response to tunnelling: Case studies from the Jubilee Line Extension, London is the result of this work. Volume 1 describes the relevant part of the JLEP, the methods of settlement prediction and building damage assessment used on the project, and the objectives of the research. Further chapters provide accounts of the geology and historical development of more of the case study buildings (between Green Park and Canada Water stations of the JLE route). Full transcriptions are included of the before-the-event and independent best practice predictions of surface and at-depth ground movements at two greenfield sites and the settlement of four buildings, which were made specially for the research. The concluding chapter of Volume 1, written by Professor John Burland, presents the overall findings of the research to date. Volume 2 presents, in their geographical sequence, the twenty-seven case studies; from Green Park in the west to London Bridge, and then eastward to Canada Water station. These case studies include two instrumented greenfield sites and several examples of prestigious buildings in London's west end that were protected by compensation grouting. The case studies present descriptions of the buildings, the works that affected them and measurements made to record their response. This valuable and informative two volume book has been written by the experts who participated in the research and is generously illustrated with numerous line drawings, graphs, pictures and maps. Building response to tunnelling: Case studies from the jubilee Line Extension, London will be essential reading to tunnelling and geotechnical engineers and all those who have an interest in this successful and interesting underground project.