Underwater Concrete in Drilled Shafts: The Key Issues and Case Histories

Assessment and Reuse of Old Foundations

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1736-07 ◽

2000 ◽

Vol 1736 (1) ◽

pp. 48-52 ◽

Cited By ~ 6

Author(s):

Bernard H. Hertlein ◽

William H. Walton

Keyword(s):

Cost Savings ◽

Drilled Shafts ◽

Environmental Benefits ◽

Accurate Information ◽

Case Histories ◽

Large Cities ◽

Nondestructive Tests ◽

New Construction ◽

Foundation Type ◽

Timber Piles

Little is known about the foundations beneath many historic buildings and bridges. For rehabilitation projects, it is important to know the nature of the foundation system and its condition. In replacement projects, cost savings and sometimes environmental benefits can be gained from the reuse of existing foundations in new structures. In large cities, almost any new construction involves the demolition of a previous structure, which poses the problem of what to do with the old foundations. Many are too deep to be removed economically, and some are almost certain to be in the way of proposed new foundations. It is therefore a great advantage if they can be incorporated into the new design, but to do this, the engineer must have accurate information about the foundation type and depth to estimate load-bearing capacity. The authors have worked on a number of projects in the last few years that have included increasing the load on or reusing existing foundations. Information about foundation type and depth has been gained from the use of specialized nondestructive tests. In many cases, the authors also had access to archive information that included soil borings in the vicinity to correlate with test data. The methods used to assess existing foundations and allow their inclusion in the design of new foundation systems are discussed, and case histories are given for concrete drilled shafts, timber piles, and steel sheet piles.

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Oxford Case Histories in Infectious Diseases and Microbiology

10.1093/med/9780198846482.001.0001 ◽

2020 ◽

Author(s):

Hilary Humphreys ◽

William Irving ◽

Bridget Atkins ◽

Andrew Woodhouse

Keyword(s):

Infectious Diseases ◽

Clinical Microbiology ◽

Case Histories ◽

Laboratory Techniques ◽

Epidemiological Features ◽

Organ Systems ◽

Key Points ◽

Recent Developments ◽

Key Issues ◽

Systemic Infections

The case format highlights key issues in presenting features, diagnosis, management, and prevention, and lends itself well to cases of infection. Those chosen reflect both common and important pathogens/infections, and less frequent but important conditions in terms of the outcome or the risk of onward spread. The cases are divided according to the main organ systems, such as respiratory and gastrointestinal, with a section for systemic infections and miscellaneous for those cases that do not neatly fit into any category. The book focuses on ensuring that the reader is aware of how to confirm a diagnosis rapidly, with references throughout to evolving laboratory techniques, provides advice on therapy, discusses recent epidemiological features, and addresses areas where there is some controversy. A combination of clinical photographs, imaging, laboratory illustrations, tables, and figures are included to highlight key points or features. Further reading provides information on aspects where there are ongoing developments. For the trainee in clinical microbiology and infection, it is not possible to cover all aspects of any curriculum in this format, and they are recommended to consult other sources. However, the cases presented will assist both them and their trainers in keeping abreast of recent developments and reminding them of key principles.

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Probing vacancies and structural distortions at individual defects in ceramics using EELS

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165859 ◽

1996 ◽

Vol 54 ◽

pp. 678-679

Author(s):

D. J. Wallis ◽

N. D. Browning

Keyword(s):

Structural Information ◽

Core Loss ◽

Nearest Neighbors ◽

Ceramic Materials ◽

Scanning Transmission Electron Microscope ◽

Real Space ◽

Atomic Scale ◽

Structure Property ◽

Scanning Transmission ◽

Key Issues

In electron energy loss spectroscopy (EELS), the near-edge region of a core-loss edge contains information on high-order atomic correlations. These correlations give details of the 3-D atomic structure which can be elucidated using multiple-scattering (MS) theory. MS calculations use real space clusters making them ideal for use in low-symmetry systems such as defects and interfaces. When coupled with the atomic spatial resolution capabilities of the scanning transmission electron microscope (STEM), there therefore exists the ability to obtain 3-D structural information from individual atomic scale structures. For ceramic materials where the structure-property relationships are dominated by defects and interfaces, this methodology can provide unique information on key issues such as like-ion repulsion and the presence of vacancies, impurities and structural distortion.An example of the use of MS-theory is shown in fig 1, where an experimental oxygen K-edge from SrTiO3 is compared to full MS-calculations for successive shells (a shell consists of neighboring atoms, so that 1 shell includes only nearest neighbors, 2 shells includes first and second-nearest neighbors, and so on).

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