Article Data Management

Electronic tendering protocol for geotechnical works

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  • All electronic information provided on an extranet shall be properly indexed and organised with all information relevant to the geotechnical works being easily identifiable.
  • All electronic information provided on a CD or DVD, or similar, shall be properly indexed and organised with all information relevant to the geotechnical works being easily identifiable.
  • It is preferable that only information specifically relating to the geotechnical works is provided.
  • All electronic information shall be provided in .pdf format that is easy to read and locked so that no unauthorised amendments can be made.  This information may include:
  1. Contract conditions
  2. Specifications and schedules
  3. Site investigation reports, including the borehole logs
  4.  Drawings
  • Drawings shall also be provided unlocked in AutoCAD .dwg format
  • Relevant forms shall also be provided unlocked in MS Word or Excel format.
  • All schedules shall also be provided unlocked in MS Excel format.
  • Site Investigation data shall also be provided in AGS format.

Copyright Regulations Potential Loss Risk or a Hidden sources of Revenues

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Every document issued in the pursuit of producing site investigation information is in some way affected by:

Copyright and Related Rights Regulations 2003 SI No. 2498

Many people are unaware of the important changes in the law brought about by the enactment of these regulations in October 2003. The key point of note with respect to site investigation work is the changes in the law regarding the copying of documents for research. This is a key factor in the production of desk studies.

There is useful a document available for download from the Copyright Licensing Agency (CLA) at:

It states in this document that:
“..under the old law, copying undertaken for research or for private study was an exception; provided that the copying could be classed as ‘fair dealing’..”

It goes on to say that:
“Under the new law, any copying for research or private study, which is carried out for a commercial purpose, will require prior permission from the copyright owner or a CLA license to permit certain copying.”

Conversely documents produced by business are now better protected and rights to further payments for multiple reproductions of reports are inherently supported more strongly by the change in the law.

There may be exceptions to the regulation where the documents being produced incorporate copies of other works are expressly for the use of a court of law or recognised arbitration body. However, individual circumstances should be checked as there may be case specific exceptions.

The CLA operates a free help line to answer queries about copyright and the need for licenses: 0800 085 6644

Loss Prevention Measures

1. Obtain a copyright license relevant to your business.

2. Where an item is not covered by the license obtain permission to copy from the author, or rights owner.

3. Study CLA guidance in this area.

4. Protect your own copy right, where appropriate.

5. When producing documents consider what reasonable charge you might make for its reproduction in advance of being asked.

6. If you chose to allow reproduction seek legal advice on the reliance others may place on it as a result of you granting permission for copying and distribution.

TC White
Marquis & Lord

Article Data Management Laboratories

BRE SD1:2005 – Implication for SI & Specifications

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The Building Research Establishment (BRE) has recently revised Special Digest 1 “Concrete in aggressive ground”. This new edition (SD1: 2005), funded by The Concrete Centre, was published as a single volume in June, following the completion of a four year research programme on combating the thaumasite form of sulphate attack (TSA) . There are two key changes to the procedure for assessing the ground;

1. The limits of the design sulphate classes based upon 2:1 water/soil extract tests on soil have been reduced to bring sulphate classifications based on 2:1 water/soil extract tests and on groundwater into parity. This will result in some sites being rated as more aggressive to concrete than hitherto.

2. High magnesium levels are no longer taken into account for natural ground.

There are five key changes to the procedure for the specification of concrete;

1. The recommended maximum water/cement ratios and the minimum cement contents have been revised.

2. A new classification for cements and blended cements has been introduced to harmonise with European standards.

3. The recommended concrete quality now caters for the inherent possibility of exposure to an external source of the carbonate required for TSA.

4. The number of additional protective measures to be applied at higher sulphate levels has been reduced, in general by two.

5. The use of the concept ‘intended working life’ replaces that of ‘structural performance level’ to harmonise with European standards.

BRE has told FPS that the take up of its revised SD1 would likely be slow as it has received no funding to mount a promotional campaign. It is relevant to note that currently some of the on-line information services are still offering just the SD1:2003 version, some 6 months after publication of the latest edition. Also, even if professionals do know of the existence of SD1:2005, they may not feel obliged to use it at the moment as the current edition of BS 8500 Concrete refers to SD1:2003. BS 8500 will unlikely to be updated before the latter part of 2006.

It is often not clear which version of SD1 has been used to classify the ground and the concrete.

The members of the Federation of Piling Specialists (FPS) are supplied with numerous site investigation reports and Engineer’s Particular Specifications every working day. Currently it is often not clear in these which version of SD1 has been used to classify the ground and the concrete. It is the exception when clear reference is made to say SD1: 2005.

FPS requests that in future all site investigation reports and Particular Specifications make clear reference to SD1: 2005. Our Clients can then be confident that piling concrete is provided in accordance with the latest requirements by eliminating the potential for misunderstanding to enter into the specification process.

Grout is a different material to concrete and SD1:2005 is only applicable for concrete.

In addition, FPS also requests that where the foundation solution may comprise minipiles, ground anchors, soil nails, grouting, base or shaft grouted piles, permanent sleeves to piles, or cross-hole sonic logging of piles, i.e. any case where grout is likely to be used either in lieu of, or in addition to, concrete, that reference is not made to SD1: 2005 for these options. This is due to the fact that grout is a different material to concrete and SD1: 2005 is only applicable for concrete.

Tony Suckling
Technical Development Manager Stent Foundations Ltd

Chair Technical Committee
Federation of Piling Specialists

Article Data Management

A national archive of site investigation data

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As aired at the recent AGS Format discussion session following the presentation by Jeremy Giles from BGS, the concept of a national archive of site investigation data is unquestionably an excellent resource. However, the users of this facility are frequently frustrated by the ‘unavailability’ of some of the archive due to confidentiality agreements that require the BGS to not release such information to third parties. Searches by BGS against a specific location requested by a user, provide neighbouring site investigation information and print-outs of such references together with a location map indicating their sites. The user can then request either a postal or first hand study at Keyworth of a selection of such data. At this point BGS may not be able to provide all data as some of it is reserved for their exclusive use in improving the national understanding of this field of study.

Jeremy Giles agreed this was an issue but that BGS was powerless to circumnavigate such agreements. On an occasion when it had been found to have inadvertently issued such confidential data, the original sender of information had recalled all its previously lodged records! In a converse situation, a searcher of the records cited an occasion where, having found some data ‘blocked’ by BGS, contacted the original depositing company who quickly agreed to remove such exclusivity. The additional desk study information was subsequently released to the searcher following a formal letter from the depositor to BGS.

It was suggested that there should be some time bar attributable to such confidentiality agreements so that after an agreed time, the information was then allowed to be available to all. Thus AGS members may like to consider the incorporation of a common clause into their contracts stating that unless the Client expressly refused permission, the site investigation information would be sent to BGS and, after a period of time, become publicly available under normal BGS arrangements. The obvious debate to be had before this could be forwarded as a suggestion to BGS, is to define an agreed period of time.

The Client would presumably wish have a period of confidentiality so as to secure their commercial objective in obtaining the information. It is suggested that most AGS practitioners would not be too concerned as to the time period, other than easing the real problem of archiving! A period of six years may be appropriate, as much of the site investigation work in the UK is effectively carried out under hand, rather than sealed, contracts.

John Hislam
Applied Geotechnics

Article Contaminated Land Laboratories


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“We used geophysics once – It didn’t work!” – This was the somewhat challenging response which the author received from a young lady engineer at a water exhibition in the recent past. And, with the passing years of comment and observation, not an entirely unexpected reaction, for the use of geophysics in environmental and engineering projects has had a chequered, and not always positive, history.

Why is this? The search for, and exploitation of, oil reserves would not be where it is now if seismic methods, in particular, had not been available or developed to the current sophistication. Clearly engineers and environmental scientists are dealing with a shallow geological section – so shallow it can be dug up with a JCB – or at least penetrated by a set of relatively inexpensive shallow boreholes. But do we always want or need to act intrusively? Can we really characterise the inhomogeneous sub-surface with a few, one-dimensional, boreholes? YES, we say. We want to do it that way because that is how we were taught. We are suspicious of something which is remote sensing, something which smacks of Black Magic. We want to get into the soil/rock. Feel it. Touch it. Smell it. Well – can you do it over a hectare and be sure that you know all the local changes hidden there? How many boreholes at one-metre centres would this be?

Clearly geophysics will not always prove to be the cheapest solution. Where the ground conditions are known to be uniformly changing across the site and there is no anthropogenic interference, what better than a few boreholes to prove what was known (or at least suspected) to be the case. But what about the other sites where conditions are heterogeneous and man’s past activity has left a legacy?

Using geophysical methodologies, the variability of sub-surface properties can be measured on a grid, along a series of profiles, down or between boreholes. Two-dimensional profiles can be constructed and, given sufficient data, the three-dimensional sub-surface structure deduced. The science is volumetric and (apart from when used in boreholes) non-invasive. It provides spatial data. As a reconnaissance tool it can be used to identify the most technically effective borehole locations for the geoscientific programme. It rarely supplants the use of borehole measurements which are required to provide “ground truth” and calibration. It can considerably improve the understanding of the variability of subsurface conditions and, used wisely, can greatly improve the cost-effectiveness of a site investigation programme.

Early guidance on the use of geophysics by an experienced professional is essential if the programme of works is to be of material value to the investigation programme. The 1993 report by the Site Investigation Steering Group of the Institute of Civil Engineers, “Site Investigation in Construction”, distinguished between the Geotechnical Contractor and the Geotechnical Adviser. A similar distinction can be made between the Geophysical Contractor, chosen for his practical abilities and specific skills, and the Geophysical Adviser, providing an independent view to the client as a consultant. The Advisor understands not only the science, but also the capabilities of the contractor and the needs of the engineer and environmentalist.

For the requirements of the ground investigation to be achieved it is important that the needs of the main consultant and client are fully understood and the abilities of the current geophysical “state of the art” appreciated. With objectives adequately defined and site constraints understood, the most appropriate method can be chosen for the situation, the survey line layout optimised and the best station spacing identified to achieve a useful data set.

Interpretation of these data to arrive at a meaningful evaluation is dependent on a basic knowledge of the ground conditions at the survey site from which a model can be developed to fit the geophysical data measured. It has to be appreciated that these data relate to the lateral and vertical variation of the physical properties of the underlying soil or rock strata. The integration of “ground truth” and the derivation of a sub-surface model are dependent on close collaboration between the geophysics team and the engineering and environmental staff.

This link is vital and allows the development of a site model drawn from the corporate experience of the team – creating confidence in the method and the results obtained.

The geophysical approach should be to ask a series of questions up-front:

Objectives: What is the nature of the site and are there physical constraints anywhere? What are the perceived problems in this area and what accuracy is required? Can these be addressed by a particular methodology or is a combination needed?

Deliverables: What does the client’s consultant need/expect? How does he want it presented? Is the time scale realistic? What control may be available? Is the data to be integrated?

Methodology: How should the survey be undertaken? Can the client afford this best approach? What can be achieved by a more limited study? What techniques are really most useful? Is geophysics really appropriate?

Only by careful pre-appraisal of a site and the desired objectives can the “didn’t work” tag be avoided.

Whilst most geophysical methods were originally developed by the mineral and oil prospecting professions, most have now been refined to provide higher resolution solutions for shallow engineering and environmental studies. Not to be mistaken for a single “remedy”, geophysics has many facets: –

Seismic operates in Refraction, Reflection and Transmission modes. It has applications in depth to bedrock, reconnaissance of layered structures, foundation studies and rock fracture conditions and detailed geological structure. A wide range of resolution is available.

Gravity measurements can identify shallow voids, fractured or weathered zones in rockhead as well as define fault locations and basic geological structure.

The surface extent of natural radioactivity is related to the underlying geology. Thermography is also an areal method which can provide information on shallow sub-surface disturbed areas, drainage zones and springs. Electrical methods using direct or low frequency currents have a value in determining water bearing layers, measuring thickness of weathering and overburden, and identifying faulted or polluted zones.

Electromagnetic techniques with either a remote transmitter or controlled close transmitter can assist in structural and stratigraphic studies as well as locating manmade buried objects. The methods are also used in water prospection and archaeology.

Magnetic data are often used both in a reconnaissance mode and in detailed surveys for archaeological and pollution studies for detection of ferro-magnetic objects and related features.

Ground Penetrating Radar has gained popularity in civil engineering for identifying buried pipes, obstacles and cavities and non-destructive testing of road surfaces and concrete structures. For further information on these techniques, CIRIA, in conjunction with the Engineering Group of the Geological Society, has produced a useful reference book “Geophysics in Engineering Investigations” (CIRIA C562). The Environment Agency also has incorporated geophysical “Investigation Method Summary Sheets” within its two volume Technical Report “Technical Aspects of Site Investigation” (P5-065/TR).

The author is a specialist in the use of geophysics for near-surface projects and keeps in touch with several European centres that are further refining and developing technologies. Whilst many of these have benefited from the considerable advances in the use of geophysics for petroleum exploration, a great deal of research is now directed to particular applications in the engineering and environmental areas. Can you afford not to gain the benefit of this experience in expanding your knowledge of the application of geophysics to ground investigations?

John C R Arthur Top-Hole Site Studies Ltd

Article Uncategorized Contaminated Land Loss Prevention


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All too often Site Investigation work is seen solely to provide soil strength parameters to enable economical foundation design. There is a need for the site investigation industry to make clients more aware that the aggressive nature of the ground should also be accurately determined if adequate precautions are to be taken in the design of a durable concrete for use in the foundations.

The problems associated with the thaumasite form of sulfate attack (TSA) have been well documented and in August 2001 BRE Special Digest 1 was published. Part 1 of the digest is particularly relevant to the site investigation industry. Without the necessary soil and ground water testing to determine the extent of those aggressive chemicals present at a particular site the concrete cannot be designed in accordance with best practice. It is where possible beneficial to have results from both groundwater and soil samples.

Many Site Investigation reports are issued without fundamental site-related parameters to enable the adequate design of the concrete.

The site assessment procedures should vary depending on whether the site can be defined as natural ground, brownfield containing industrial wastes or pyritic ground, reference to BRE Special Digest 1 should be made for full details.

In general it will be necessary to determine the water soluble sulfate in 2:1 water/soil extracts and the pH in 2.5:1 water/soil extracts. Many Site Investigations where they report any chemical testing only show an occasional soluble sulfate result which is often inadequate to determine the Design Classification for the concrete mix. Where the sulfate in the soil extract exceeds 3.7 g/l SO4 or in the groundwater sample exceeds 3.0 g/l SO4 it is necessary to also determine the Magnesium content. The mobility or otherwise of the groundwater on site also has an affect and should be established.

Where a site is brownfield it will generally be necessary to obtain the Chloride and Nitrate content in both the soil and groundwater samples if the aggressive chemical environment for the concrete is to be accurately determined. Where Pyritic ground conditions are anticipated more substantive testing is required to enable the total potential Sulfate and hence the concrete design requirements to be determined, for full details reference should be made to BRE Special Digest 1.

It should be apparent from the above that greater consideration needs to be given to determining the aggressive chemical environment at the site investigation stage than is currently the case, to determine site-related parameters for strength in one site investigation and then undertake further work at a later date to enable the Aggressive Chemical Environment for Concrete to be determined is no way for the industry to improve its standards or its advice to clients.

It should also be noted that BRE Special Digest 1 has superseded BRE 363.

D.Brightman Technical Manager, Rock & Alluvium