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There have been many changes in the UK geotechnical industry over the past 25 years. Traditionally, specialist geotechnical contractors recruited talented young engineers and geologists at the very early stage of their careers (normally direct from university). These contractors were usually subsidiary firms of major civil engineering contracting companies. The young engineers and geologists were put through an in-house foundation engineering development programme and usually gained onsite experience, being involved in many different types of foundation contracting activities e.g. site investigation, piling, grouting, diaphragm walling etc. In the offices, laboratory testing and foundation engineering design were also undertaken. Graduate trainees were often seconded to the parent company's civil engineering sites for earthworks and other work of a geotechnical nature, thereby enabling the person to experience how his work fitted into the overall civil engineering scene. The result of the in-house development programme over a period of four to five years, resulted in the young engineer or geologist becoming competent in the why's and wherefore's of geotechnical engineering. In particular, they could understand why a site investigation was required, the design and construction requirements for different types of structures and buildings, methods of investigation, appropriate laboratory testing and different foundation solutions etc. These engineers and geologists became "geotechnical engineers" and when carrying out site investigation projects, were expected to supervise onsite operations, write reports and liase with clients, consultant engineers etc. They were also expected to be sufficiently competent to recommend alternative onsite techniques to obtain the best solution commensurate with the overall objectives of the project. As a consequence of the increased use of subcontract drilling organisations during the past 20 years, the specialist geotechnical contractor's "bread and butter" site investigation market shrank considerably. This, combined with a change in attitudes within the geotechnical industry, in particular the mushrooming of the many geotechnical departments of civil engineering consultants, has culminated in less opportunity for geotechnical engineers to gain such experience. Geotechnical engineers with this particular type of practical experience might thus be considered an endangered species, "GeoDodos". There is now a distinct scarcity of this type of geotechnical capability within the industry. There are very few specialist geotechnical contracting companies that are able, or prepared, to offer any in-house training development programmes. It is now not uncommon to find that both the specialist site investigation contractor and consultant engineer have employed temporary subcontract staff from agencies to carry out both of their respective supervision duties. A recent survey indicated that consultant engineers would much prefer that specialist site investigation contractors provide their own suitably trained geotechnical staff on site and not use engineering staff from agencies. Some site investigation contractors would probably make the same statement about consultant engineering staffing arrangements. These comments highlight the staffing problem that the geotechnical industry has to cope with. Many newly academically qualified engineering geologists who find work with employment agencies have nothing to look forward to, except the mundane tasks of logging and basic site testing and supervision. There are also "pure" geologists who have become disillusioned after a couple of years of North Sea mudlogging and are looking for geotechnical employment, but who have no background engineering training. Many site investigations carried out by contractors now only require factual reporting; thus geotechnical interpretation expertise within site investigation contractors may be in the decline. Graduates are unlikely to be able to obtain the "all round" training and experience that is required of a geotechnical engineer. In the geotechnical industry, we have concentrated on trying to put forward the case of pursuing excellence and quality within our industry by specifying the job titles geotechnical specialist and geotechnical adviser which require various combinations of academic achievement and experience. The "aspiring" geotechnical engineer advises on the intricacies of finite element analysis, the importance of good quality laboratory testing and investigations. However the lack of proper training can result in him being "blind" to the major benefits of a quality site investigation, which include accuracy and relevance to say the least. We can, with some confidence, assess the academic achievements but have no way of assessing the worthiness of any training or experience gained. The Continuing Professional Development objectives of the various Institutions may be considered as going some way towards this goal, but the experience and training needed is at the early stage of their careers, before achieving chartered status. There is a need for proper training and meaningful experience to develop geotechnical engineers. There are practical on site induction courses on drilling methods that are promoted by the British Drilling Association and the recently produced AGS Laboratory Testing Guide provides a valuable insight into the sampling, testing requirements and rationale. Worthy as they are, these alone are not sufficient. It is unlikely that specialist geotechnical contractors and consultant engineers can carry this out alone but, together perhaps with the support and guidance of the relevant institutions and academia, a combined development programme could be evolved. The employment agencies that provide engineers and geologists purporting to be geotechnical engineers should take a more active role in geo-professional training and development and improve the "product" that they are selling. If young engineers and geologists do not have the opportunity to undergo training and develop, it might be that early in the next millennium the trained experienced geotechnical engineer like the Dodo becomes extinct. Jim Cook
INNOVATION IN GROUND INVESTIGATION
It is generally acknowledged that there has been little innovation in ground investigation for many years. The structure of the industry, together with the various forms of contract, specifications, standards and procurement methods, has favoured a traditional approach based upon tried and tested techniques. Some would argue that this conservatism has stifled innovation, and has contributed greatly towards the low status of the industry today. The argument continues that there is a crucial role for the AGS in liberating the industry from its lacklustre past by breaking down the barriers which have blocked free thinking and innovation. Perhaps this line of thought is at odds with some of the current initiatives to 'tighten up' and 'control' the industry. In any industry, successful innovation leads to higher standards, greater efficiencies and increased wealth. Innovation involves both financial risk and risk to personal reputation. Nevertheless, it is fundamentally essential. It is inevitable that, unless innovation is embraced, the
current "low common denominator" approach to ground investigation will
ultimately be ignored by those at the forefront of the industry. Dynamic Sampling is the new technique developed by Geotechnical Engineering Limited for soft ground sampling for geo-environmental and geotechnical assessment. It is carried out using one of the company's 'state of the art' Pioneer drilling rigs. A continuous 'nearly undisturbed' sample of soft ground is recovered from a borehole, contained in a semi-rigid transparent plastic liner, which is then laid in sequence in a core box. The liner can be easily cut open at any time for logging and sub-sampling for laboratory testing, and can be resealed for long term storage. The technique produces samples of diameters up to 112mm, and is effective to about 20m depth. All types of soft ground can be sampled, including sands, silts, clays, some gravels, and a variety of fill materials. When sampling contaminated ground, contact between personnel and potentially hazardous materials can be avoided. Very little spoil is produced. The Pioneer is a compact hydraulic top-drive rig, which travels to site on a trailer towed by a Landrover. It moves around site on rubber tracks with minimal disturbance, and copes with a variety of terrain. It can even pass through a standard doorway and operate inside buildings. The Pioneer also incorporates full rotary core drilling capabilities for hard ground. The driller can easily switch between rotary techniques and Dynamic Sampling techniques. Additional facilities are incorporated for installing monitoring wells, grouting boreholes, carrying out SPT's and taking undisturbed samples. Vertical and inclined boreholes can be formed in soft and hard ground. It is interesting to note that much of the work carried out by the company's Pioneer rigs is procured outside the traditional form of contract and specification. Andrew Milne Do you have new technical innovations to report? The Editor
of the AGS Newsletter would welcome further articles drawing attention to
technical advances. Information should be sent to Dianne Jennings at the AGS
office. New Quarries Regulations will come into force on 1 January 2000. They are accompanied by an approved Code of Practice published by HSE (reference no. L188). The Regulations replace 13 pieces of existing quarry legislation (see below) and address the safety of excavations and tips, the safe use of explosives, the design, construction and maintenance of benches and haul roads, and workforce participation. Regulation 3 deals specifically with the geotechnical assessment, including the definition of the competencies required by the specialist carrying out the assessment. This is specified as a Chartered Engineer or Chartered Geologist with at least five years relevant experience The ISBN no. is 0717624587 The new Regulations repeal and revoke the following: Mines and Quarries Act 1954 (Quarries part) How well recognised is the AGS Code of Conduct? As part of a market survey in which a questionnaire was sent to nearly 500 consultants, both AGS members and non-members, Foundation & Exploration Services Limited (FES) sought to determine inter alia, the perception among consultants of current market conditions and practice in site investigation. The results showed that in general, civil, structural, geotechnical and geoenvironmental consultants and employers require a higher standard of site investigation than is currently achieved. More than half of the 84 respondents support the AGS Guidelines for Best Practice in Site Investigation and the Code of Conduct and almost half stated that membership of the AGS influenced their choice of contractor. However, many were of the view that compliance with the Code of Conduct may be difficult to achieve. Most respondents preferred a voluntary code to the idea of regulation by statute. The responses were grouped into categories according to the total annual expenditure each respondent commissioned on site investigation. Broadly speaking there was a difference in perception among those respondents involved with a total annual expenditure of less than £250,000 and those respondents with a greater annual value of site investigation expenditure. The survey showed that consultants recognise the commercial restraints imposed on site investigations by competitive tendering against the high level of investment required of contractors to provide a quality service, e.g. investment in qualified personnel and modern plant and equipment. A high percentage of those awarding contracts exceeding a total annual value of £250,000 consider it important to maintain standards and personnel. However, the majority of those respondents with a lower annual expenditure were generally satisfied with the standards of site investigations carried out on their behalf. Almost all (97%) of the higher spending practices believed that better quality site investigations would have led to savings on costs for subsequent piling grouting or anchoring works, whereas as much as a quarter of the lower spending practices felt that they could offer no opinion. Few respondents felt that they could quantify precisely the additional costs incurred as a result of a poorly executed site investigation particularly those costs borne by themselves or the employers in extra management time. Consultants gave as their highest priority for change in the industry the need to instil in employers a much greater technical appreciation of the commercial risks arising from poorly designed or executed site investigations. The general perception as to which party has the most influence on good practice was not in favour of any one party although more respondents (40%) placed the onus on consultants than employers (30%) or contractors(30%). The majority (60%) support improved communication with employers and developers to promote the benefits of greater investment in high quality investigations. It was suggested by some respondents that this could be achieved by a joint initiative between the AGS and consultants. A copy of the AGS Code of Conduct can be found on this site. The Code has been edited to improve the English and to make the requirements for consultants, contractors and SI contractors more consistent. Further copies - and copies of the AGS Guidelines for Good Practice in Site Investigation are available on request. Notes on the October 1999 Draft of the Statutory Guidance on Contaminated Land. Implementation of Part IIa of the Environmental Protection Act 1990. 1. The new regime will be in force from April 2000.
3. Concerns on the 1996 Draft centred around; i)
resourcing the implementation
Discussions on this aspect are still ongoing. Hugh Mallett BS 5930 - finally makes its appearance The long expected revision of the Code of Practice for Site Investigations (BS 5930: 1999) has been published. Copies are available from BSI (Tel: 020 9996 9001; email: (orders) orders@bsi.org.uk) or (enquiries) info@bsi.org.uk). |
