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Thesis (Ph. D.)--University of Sydney, 1990. / Includes tables. Title from title screen (viewed November 06, 2009). Bibliography: leaves 360-369. Also available in print form.

The thesis falls naturally into four parts. The first constitutes a world-wide survey of the methods used in practice to design prestressed, cement grouted rock anchors. The major topics of overall stability and system geometry, the rock-grout and grout-steel interfaces, and grout and tendon selection, are reviewed in turn. Comparisons between the standard methods of practice, and the findings from theoretical and field studies, reveal important areas of uncertainty and contradiction, particularly with regard to the mechanisms of load transfer from tendon to rock. Part 2 describes the author's full scale test anchor programme, conducted at Withnell, Lancashire, devised to investigate the major problems associated with load transfer which were highlighted in Part 1. Full details are provided of the site and its geology, and the methods of construction, testing, recording and analysis employed. Most emphasis placed on the results obtained from the fifty-seven anchors: these are fully discussed and wherever possible compared with data presented in the review. The third part deals with the long term performance of rock anchor systems. Analogous to Parts 1 and 2, one chapter is devoted to a review of relevant published information, whereas the other chapter details the author's case study of ten production anchors at H.M. Dockyard, Devonport. In Part 4, conclusions on the field test programmes are summarised and indications are given of topics meriting further research.

Current methods for assessing the integrity of ground anchorages during service are primarily restricted to monitoring by load cells or load lift-off testing. Both are expensive and lift-off testing is time consuming and can damage the anchorage construction below the anchor head. Hence, only typically 5-10% of anchorages are monitored in service. As a result, The Institution of Civil Engineers reported that non-destructive test methods for ground anchorages need to be developed as a high priority (ICE, 1992). The Universities o f Aberdeen and Bradford have been conducting research since 1986 to investigate the response o f rock anchorages to dynamic loading arising from blasting operations. Full scale field trials were conducted during the construction of two tunnels in North Wales. An important finding from the research revealed that certain characteristics of the dynamic response of a rock bolt resulting from blasting operations, were similar for different blast sequences. This indicates that the dynamic response o f an anchorage system is dependant on the construction of the anchorage and the characteristics of the co-vibrating rock mass. Consequently, the University of Aberdeen has developed a new non-destructive condition monitoring and integrity assessment system for ground anchorages (GRANIT ™). A range of patent applications have been successful world-wide and the system has been exclusively licensed to AMEC Civil Engineering Limited. The system operates by applying an axial tensile impact load to the free end of an intact anchorage immediately after installation. The resulting vibrational response is monitored by an accelerometer, located at the anchorage head, which produces a datum signature for that anchorage. The condition of the anchorage is then inferred by comparing subsequent response signatures with the datum. A change in the signature indicates that there may be a potential change in the integrity of the anchorage. Artificial Intelligence systems are employed to compare response signatures. As part of the research programme, the author conducted commissioning tests on small scale laboratory test rigs and was responsible for the development of a prototype non-destructive test system, which included a means of applying an impact load and recording the vibrational response. In addition, the author conducted full scale laboratory tests and field trials to investigate the effect of prestress on the dynamic response of ground anchorage systems. As a result, the prototype non-destructive test system has been employed to successfully predict the amount of load within an anchorage installation.

Thesis (doctoral)--Monash University, 2000. / Contains two volumes.

Thesis (M. Sc.(Mining Engineering))--University of Pretoria, 2002. / Includes bibliographical references (p. 78-81).