Article

20 Years of SiLC

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Introduction
The SiLC Register was launched as a consequence of the work of the Urban Task Force which recognised the need for competent people to work in a sector that embraces many different disciplines. The Register includes professionals from the broad range of backgrounds that advise on land condition matters and provides evidence of competence in this field. After 20 years it continues to this day, and this is testimony to the need for and value delivered by the Register.

History
The Urban Task Force was established in 1998 by then Deputy Prime Minister John Prescott and chaired by Lord Rogers. Members were chosen for their expertise in the many elements which are necessary for an urban renaissance including sustainable development, urban design and urban regeneration. Its purpose was to identify the causes of urban decline and to establish a vision for our cities, founded on the principles of design excellence, economic strength, social wellbeing and environmental responsibility within appropriate delivery, fiscal and legal frameworks. At the time there was a Government target for 60% of new homes to be built on previously developed (aka brownfield) land.

The report from this taskforce, entitled Towards an Urban Renaissance was published in 1999 with over 100 recommendations which included the identification of the benefits of greater consistency in the handling of information on land contamination. It recommended the introduction of standard documentation describing the condition of the land, with the purpose of ensuring that during the sale, purchase and development of land, all parties had access to the same data sets and could therefore develop some general agreement between them on the levels of risk associated with that particular site or that particular use.

This concept was further developed by a working group chaired by Phil Kirby of BG Properties. Members of the working Group included Phil Crowcroft and Hugh Mallett. The working group also concluded that it would be essential to set up a qualification in order to sign off this standard documentation. The Specialist in Land Condition (SiLC) Register was therefore established in 2000 focused on setting high standards in the industry.

Mike Summersgill recalls that “Judith Lowe, who was technical co-ordinator for the working group, decided to put together a group of people, one from each Professional Institution and the AGS, to formulate an examination method to verify (by peer review, as still done now) those people that could ‘sign off’ the standard document. There were 6 grandparents, chartered professionals, including Judith Lowe, Peter Braithwaite (ICE), Paul Syms (RICS), Hugh Mallett (AGS), Colette Grundy (RSChem) and myself (CIWEM).

There was a pilot examination, with the above six being the Panel of Assessors; 13 people sat the exam, all passed. Those passing included, Phil Crowcroft, Doug Laidler, Jonathan Steeds and Peter Witherington. The next examination was in January 2002, with 13 passing including Roger Clark and Paul Nathanail. In June 2002, another 18 people passed including Padraig Daly and Claire Dickinson, bringing the total to 50 including the 6 grandparents. During that initial exam process, we identified those candidates who might be Assessors, so by early 2002 we had 10 more Assessors. In late 2002 they examined three of the six grandparents and verified us as SiLCs.”

From the inception of SiLC it has been administered by a Professional and Technical Panel (PTP) consisting of professional and technical representatives from each of the supporting professional institutions and the AGS, plus one or two co-opted members who provide a specific input to the PTP. The secretariat for the scheme is Forum Court Associates who were appointed in March 2015.
In 2011 Specialist in Land Condition Register Limited was established with a board of directors comprising representatives from the institutions and the AGS. The purpose was to protect the liability of those individuals who give their time and energy to managing the qualification process and to provide a higher-level approval process regarding the financial stability of SiLC and other key decisions recommended by the PTP.

SiLC Today
To become a SiLC it is necessary to pass an open book exam and an interview to demonstrate that a candidate meets the SiLC Criteria. SiLC are also the accreditation body in respect of Suitably Qualified Persons (SQPs) under the National Quality Mark Scheme (NQMS) promoted by the National Brownfield Forum (formerly the Land Forum). Passing the SiLC exam and interview, and a NQMS specific test, enables a candidate to also become an SQP. Chartership is a prerequisite for both. Hugh Mallet leads the exam sub-group who prepare each set of questions for the exam covering technical, legislation and formal guidance issues. Each year there are a number of Introduction Days around the country to explain the process of the exam. These events are mainly prepared and presented by Peter Witherington and Hugh Mallett.

There are now 195 SiLCs and 116 SQPs with another 7 candidates sitting the 2020a exam. It is true to say that the number of applications to become SiLC/SQP has increased in recent years since the launch of the NQMS. This underlies the determination of the profession to aspire to higher standards in the outputs they produce and to recognise the benefits of qualifications that demonstrate capability and quality.
The SiLC Affiliate Scheme was launched in 2018 and is intended to assist graduates, as well as more experienced individuals, to follow an integrated process towards full membership of a professional body and chartered status with the assistance of a professional body adviser, and then progress towards SiLC/SQP registration with the assistance of a SiLC mentor.

In January 2020 the Directors of SiLC Register Limited elected Roger Clark as Chair of the Board of Directors to succeed Phil Crowcroft who was Chair of the Board from 2011 to 2019 and Chair of the PTP from 2008 to 2017. The Board also elected Dr Paul Nathanail as Deputy Chair of the Board with the intention that Paul will succeed Roger as chair in two years’ time. The SiLC PTP is currently chaired by Ian Evans who in March 2020 succeeded Paul Burden (2017 to 2020).

In a recent interview published in the AGS eMagazine Phil Crowcroft said “SiLC delivers confidence that an individual has core competence in their own subject area whilst recognising and appreciating the parallel skills which are needed to deliver the reclamation and redevelopment of brownfield sites.” The dedication, hard work and leadership by Phil have brought SiLC as far as it has come today and the SiLC Register will always be grateful to him.

Looking Forward and Thanks
A big thanks to those mentioned in this article who have contributed to the success of SiLC over the last 20 years. Members of the Board, PTP and the SiLC Assessors are individuals who give their time and effort free of charge. Special thanks go to Doug Laidler who was one of the first Pilot SiLCs (8th). Doug sadly passed away in December 2019; he was a hugely respected professional consultant working on land contamination matters for many years and was the secretary of SAGTA.

SiLC looks forward to another 20 years of championing good quality in land condition.

Written by Grace Hawkins, SiLC Secretariat

SiLC and Affiliate Scheme application forms can be downloaded from https://www.silc.org.uk/application/becoming-a-silc/. Information on the NQMS can be obtained from www.claire.co.uk/nqms.

Article Loss Prevention

FIDIC Emerald Book and Geotechnical Baseline Reports

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On 7 May 2019, FIDIC (International Federation of Consulting Engineers) published its First Edition of the “Conditions of Contract for Underground Works”, otherwise known as the “Emerald Book”, which was produced in conjunction with the International Tunnelling and Underground Space Association.

The General Conditions of Contract in the Emerald Book are based on an earlier FIDIC publication, but the Emerald Book also features a new set of clauses and introduces a new document – the Geotechnical Baseline Report (“GBR”).  These seek to achieve a balanced allocation of the risks arising out of the ground conditions, which for underground works such as tunnelling are not possible to assess with precision at tender stage. The new clauses and the GBR provide a mechanism for adjusting the completion time and the contract price remuneration according to the actual ground conditions encountered, in comparison with those outlined in the GBR.  The GBR provides a model which serves as the sole contractual source of risk allocation related to subsurface physical conditions, and their geotechnical properties, and defines the ground conditions risks assumed at the outset by the Contractor. Hydrogeological, geological and geotechnical properties of the ground, or contamination conditions not addressed by the GBR are considered to be ‘unforeseeable’ and therefore any differences are then deemed to be at the Employer’s risk.  The risks arising out of the foreseen ground conditions, as described in the GBR, are assigned to the Contractor.  It will create a reasonably “level playing field” which will allow the various bidders to base their proposals on a similar risk basis.

Another key document is the Completion Schedule which specifies the “Time for Completion” based on the Contractor’s estimated rates of progress. These are calculated by reference to the ground conditions and working methods as described in the GBR.  The Time for Completion can be extended if the conditions encountered are more onerous than those assumed, and it can also be reduced if conditions are less onerous than those anticipated from the GBR.

The Engineer has a central role in assessing the Contractor’s measurement of excavation and lining works against the baselines set out in the GBR. Adjustments to the Time for Completion and remuneration are based on this assessment.  Appendix A to the Emerald Book provides guidance as to what information the GBR should contain.

Geotechnical Baseline Reports are significantly different from the traditional geotechnical factual and interpretative reports described in British Standards, and from the Ground Investigation Report (GIR) and Geotechnical Design Report (GDR) described in Eurocode 7.  Geotechnical baseline reporting is used to manage the commercial aspects of geotechnical risk, not for geotechnical design, so will  have a different emphasis than those elements more familiar to most geotechnical and geoenvironmental  specialists.

There are currently no UK industry guidelines on how GBRs are prepared, or what they should include. However, the objective is that their use in tunnelling contracts can benefit both the Client and the Contractor by leading to effective and fair risk control.

The Construction Industry Research and Information Association (CIRIA) has a project underway, P3165 – Geotechnical baseline reporting, which aims to provide good practice guidance on geotechnical baseline reporting, provide industry with a consistent approach to producing GBRs, encourage the use of GBRs on smaller scale projects and provide better outcomes for managing geological and geotechnical risk.  The project should be completed in early 2021.  See the CIRIA website for more details.

Unsurprisingly, there are no reported decisions of disputes arising under the Emerald Book as yet, or of disputes that may have been avoided through its use.  The AGS Loss Prevention Working Group will keep this under review and will provide further guidance in due course regarding the opportunities and risks that the Emerald Book and the use of Geotechnical Baseline Reports present for AGS members.

Article provided by Zita Mansi, Senior Associate, Beale & Co

Article

The Geotechnical Asset Owners Forum

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The Geotechnical Asset Owners Forum (GAOF) was formed in 2008 by like-minded organisations from the transport sector which manage geotechnical and related assets.  The Forum usually meets four times a year and provides a platform for the sharing and exchange of ideas. The Forum facilitates topical, important and forward thinking discussions for the mutual benefit of the asset owning community and the users of those assets.

The scope of the Forum comprises the management of geotechnical and related assets, which include the following: earth structures – typically embankments and cuttings; foundations; retaining structures; geotechnically processed ground – typically stabilised or improved ground; and earthworks drainage.

GAOF is a self-financed membership based forum, endorsed by the Department for Transport.  The Construction Industry Research and Information Association (CIRIA) provides the administration.

Objectives

The Forum aims to:

  1. pool ideas and experiences in managing geotechnical infrastructure for collective benefit by the identification, development and dissemination of associated research, advice and Standards;
  2. identify and prioritise technical and research needs on topics which promote good practice management of geotechnical assets by influencing research and other activities which support the priorities identified by the membership;
  3. promote co-operation, collaboration and partnerships amongst geotechnical owners through inviting select organisations to become members; and
  4. develop an effective communication strategy to promote and publicise co-operation and collaboration within the geotechnical infrastructure community.

Geotechnical Asset Owners Forum Founding Members
Highways England
Network Rail
Transport for London – London Underground

Geotechnical Asset Owners Forum Supporting Members
Transport Northern Ireland
Welsh Government 

Geotechnical Asset Owners Forum Regular Contributors
ADEPT North (Lincolnshire County Council)
ADEPT South (AECOM)
Association of Geotechnical and Geoenvironmental Specialists (AGS)
Canal and River Trust
Environment Agency
HS2
Scottish Canals
Translink (Northern Ireland)
Transport Infrastructure Ireland
Transport Scotland

The AGS is represented on the Forum and contributes to its discussions and when appropriate puts forward the geotechnical and geoenvironmental industries’ viewpoint on matters of interest to GAOF members.  Should AGS members have any particular issues they would like GAOF to consider, or would like to present to the Forum some research, new technical development, or a case history that is relevant to the aims of the Forum then in the first instance please contact the AGS secretariat.

To find out more about GAOF visit their website www.ciria.org/gaof

Article

Advice and Guidance on COVID-19

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The below advice and guidance is correct as of 5th January 2021. This list will be updated as further guidance is published.

The current advice from the Government is to:

  • Hands – wash your hands regularly and for at least 20 seconds.
  • Face – wear a face covering in indoor settings where social distancing may be difficult, and where you will come into contact with people you do not normally meet.
  • Space – stay 2 metres apart from people you do not live with where possible, or 1 metre with extra precautions in place (such as wearing face coverings).

The Construction Leadership Council (CLC) have published an updated Site Operating Procedures Version 6 on 20th October 2020. SOP V6 can be found HERE

The Construction Leadership Council (CLC) have published an update on their advice regarding face coverings (4 August 2020). This can be found HERE

Government guidance for the latest national lockdown, announced on 4 January, can be found HERE

Government guidance (as of 21st December 2020) for those working in the construction industry can be found HERE

(General) Government guidance on the current period of restrictions which can be found HERE

For up-to-date guidance and advice, please visit https://www.gov.uk/coronavirushttp://cic.org.uk/ and http://www.constructionleadershipcouncil.co.uk/

News

AGS Magazine: March/April 2020

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The Association of Geotechnical and Geoenvironmental Specialists are pleased to announce the March/April 2020 issue of their publication; AGS Magazine. To view the magazine click here.

This free, publication focuses on geotechnics, engineering geology and geoenvironmental engineering as well as the work and achievements of the AGS.

There are a number of excellent articles in this month’s issue including;
Update from the AGS regarding COVID-19 – Page 4
Are traditional sampling techniques really that bad? – Page 6
A Candid Look at Responses to SiLC Membership Questionnaire 2019 – Page 12
AGS Guide to Occupational Stress – Page 16
Q&A with Chaido Doulala-Rigby (Yuli) of Tensar International – Page 22

Advertising opportunities are available within future issues of the publication. To view rates and opportunities please view our media pack by clicking HERE.

If you have a news story, article, case study or event which you’d like to tell our editorial team about please email ags@ags.org.uk. Articles should act as opinion pieces and not directly advertise a company. Please note that the publication of editorial and advertising content is subject to the discretion of the editorial board.

Article

Q&A with Chaido Doulala-Rigby (Yuli)

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Full Name: Chaido Doulala-Rigby (Yuli)

Job Title: Business Development and Chief Civil Engineer Eastern Hemisphere (EH)

Company: Tensar International Limited

My engineering journey started in Greece where I was born, grew up and got my first degree in Civil Engineering. In my 26 years engineering career so far, that spans across the globe, including 10 wonderful years in Hong Kong working as a Geotechnical Engineer, I feel blessed to have been part of some extraordinary projects and to have met some truly amazing people both on a personal level and professionally.

Upon my return to the UK from HK some 14 years ago, I joined Tensar International and soon progressed to become the Chief Civil Engineer of the Company that invented Polymer Geogrid Technology and “revolutionised Civil Engineering” (as quoted in the ICE200 publication in 2018).

What or who inspired you to join the geotechnical industry?

I owe my initial ‘attraction’ to Geotechnics predominately to Dr Evan Passaris, who was a professor at Newcastle University upon Tyne back in the early 90’s and encouraged me to do their MSc in Rock Mechanics and Foundation Engineering. Upon my MSc completion in 1994, I joined the Jubilee Line Extension (JLE – Contract 102) that was under construction in London, working as a graduate tunnel engineer for Balfour Beatty/Amec JV. At the time, JLE was the largest Civil Engineering project in the UK and still remains one of the most expensive projects in the world of all times at over £4 million per meter of its 16km length!

Looking back, I can confidently say that, while my MSc intrigued my appetite for Geotechnics, it was joining the JLE tunneling project that cemented my decision to follow Geotechnics. It taught me to expect the unexpected when dealing with soil, which fascinated me and encouraged me to further explore the weird and wonderful world of Geotechnics. And here I am, just over a quarter of a century later, still in Geotechnics and still loving it!

What does a typical day entail?

There is no such a thing as a ‘typical’ day and I guess that’s the best part of being an engineer, no 2 days are the same! I love travelling and I love educating people from all backgrounds about the magnificent performance of geosynthetics and especially Tensar’s leading geogrid technology. My current role is largely a combination of both. It is quite a demanding role, that I enjoy enormously, but I have worked very hard to earn it and I still work even harder to keep up with its ever-expanding nature. Many people say I am ‘lucky’. But I don’t believe in ‘luck’. I believe we can all create our own ‘luck’, and I find that the harder I work, the ‘luckier’ I get, meaning the more I get invited to travel for Tensar. What the people that call me ‘lucky’ don’t know is the amount of preparation that goes behind the ‘glamour’ of travelling. There are many reasons for my work related travel: to present bespoke technical papers that I author to International Conferences, to deliver bespoke design training to Tensar’s various EH offices that I look after, to present our cost, time and value message to suit specific Clients’ requirements, to present our latest R&D research to technical forums, to participate to committee/panel meetings, to do STEM talks and/or activities with hundreds of school children and students, to review, interview and judge technical submissions of Industry projects’ entries on behalf of various independent Industry Awards such as Ground Engineering, ICE, Engineering Trust etc. What people that call me ‘lucky’ don’t see is the ‘red eye’ car, train and/or flight journeys that I take to get me to my destination on time and in the most efficient way and the weekends and early mornings or late nights that I spend on my kitchen table writing or assessing papers and preparing for my bespoke presentations. A large part of what I do is indeed voluntary and outside my normal, ‘day job’ working hours not because I ‘have to’ but because I choose to do so. Having gained so much experience in Geotechnics and in Engineering at large over the years, it gives me great joy and pleasure to be able to share my knowledge and give back to the engineering community, whether it is by participating in committee work, Industry award judging or getting involved in STEM work.

My ‘day job’ involves fast-track live project risk management by directing, advising, checking and indeed carrying out designs for Tensar’s multidisciplinary applications requests that land in my inbox daily from all over the world. Enquiries can vary from as simple as: “What fill can be used to build a 3m high car park retaining wall with your geogrids?” to “Can we build a 30m high dam with your geogrids?” to “Can you help us support a ~3,000ton crane over soggy paddy fields in Vietnam?!”. Or from: “Can you represent the ICE and talk about What Is Civil Engineering to students in an upcoming Engineering Day event at a University in Manchester” to “Can you come to Peru next month to present Tensar’s containment capabilities to a mining Client”! So two days are never the same and it is this unpredictable variability of what I do that I love the most, not knowing what soil type, request or idea tomorrow brings! Undeniably, there are times that managing my ever-evolving to-do list can get frustrating too, but after all these years, I have learned to know when to close my laptop and remind myself, and other like-minded colleagues, that ‘tomorrow is another day’.

Are there any projects which you’re particularly proud to have been a part of?

I take pride in every single project that I get involved with. But if I had to choose a single construction project that I got involved with in my career so far, it has got to be Tensar’s tallest geogrid reinforced soil embankment walls in Fujairah, UAE, that were constructed in 2011. The project was a massive cut and fill exercise whereby in-situ Gabbro mountains were blasted to create rock cut slopes with heights in excess of 100m, while the blasted rock was crushed and reinforced with our geogrids to form massive 60m high soil embankments to cross the valleys in between the mountains to support a new freeway connecting Dubai with Fujairah port. Our reinforced soil embankments replaced the originally proposed viaducts due to the surplus of blasted rock available and due to the access and construction difficulties a viaduct construction would pose in such harsh and arid environment. I am very proud to have led the design and supply team of Tensar Engineers to deliver this project, that included remote resource coordination, multicultural team engagement, and many site specific design alterations that I had to manage under very tight deadlines to best fit unforeseeable and challenging geomorphological conditions that were encountered during construction. And a few amazing trips to the site too!

The other ‘project’, that I take immense pride to be part of, is my voluntary role as a registered STEM Ambassador, for which I am grateful to have Tensar’s full support. My involvement with STEM started in 2018, thanks to the British Army that invited me to role model my career in Civil Engineering to young female school students, at the first ever Army-supported STEM careers’ fair. The event, that saw 900 female students aged 11-18 participating, was organised at the Military Royal Academy Sandhurst in May 2018 in support to the UK Government that declared 2018 as ‘Year of Engineering’ in an effort to help close the skill and gender gap our Industry is facing. The same event was repeated in 2019 but expanded over two days and attracted 2,000 school students of both gender and it is due to be repeated in 2020 scheduled to reach even more students from even more remote regions and form more underprivileged backgrounds, proving that there are no boundaries to engineering and that engineering is for all.

What are the most challenging aspects of your role?

On a Company level, as the inventors and leaders of polymer geogrid technology for over 40 years, Tensar’s greatest frustration is that, together with other manufacturers now,  despite the independently tried, tested and proven benefits of geosynthetics in reducing cost, time and carbon in earthworks construction, we are still trying to ‘convert’ vital sectors of our Industry like Highways and Railways and convince them to include geosynthetics in their design standards and codes, rather than still treating geosynthetics as a ‘departure’. In parallel, our added challenge is in trying to maintain top quality standards across the Industry and differentiate amongst the various geosynthetic products available in the market and their different functions. And although some companies, like Tensar, have invested a large amount of money to have our products independently tested, verified and certified in achieving a certain performance, unfortunately there are a lot of products available in the market that because they look the ‘same’, they claim that they perform the same. Our critical challenge is trying to keep up with defending our specification in our multiple live projects and trying to educate the Industry why ‘everything that looks like gold is not gold’. To this end, we have come together with other like-minded geosynthetics manufacturers and we succeeded in including some good guidance in two recent publications, namely the TWf Good Guide to Practice and the EFFC/DFI Guide to Working Platforms, whereby the advice to engineers is that, if they want to consider an alternative geosynthetic product, in a piling platform design for example,  they MUST seek an alternative FULL design rather than just swapping with cheaper geosynthetics alone; each geogrid or geotextile performs and interacts with the available fill material in a completely different and unique way, which has direct impact to the working platform design thickness and performance.

On a personal level, working for a company with Global reach comes with quite a few challenges from managing different time zones, different design codes and indeed different cultures to keeping up with local Industry updates by making time to actively participate in various technical panels and committees, often international. And while everybody is talking about ‘devolution’, most such committee and panel meetings still take place in or near London. And despite all remote digital aids available such as Webex, Skype and Teams, in a lot of such discussions, face-to-face interaction is still irreplaceable. My challenge is to plan as far ahead as possible and try to keep my diary up to date so I can fit in as many meetings as possible in a single journey, especially as I live and work ‘up’ North, in Lancashire.

What AGS Working Group(s) are you a Member of and what are your current focuses?

I am a member of the Geotechnical Working Group of AGS. Our current focus is trying to investigate, assess and compliment, if necessary, the currently Industry standards and guidance on ground improvement techniques and especially vibro stone column and dynamic compaction and their post-construction validation testing on site. Other areas of current focus of our working group is EC7-Part 2, improving sustainability in current site investigation process and the increasing volume and cost of BSI publications and its impact on SMEs, just to name but a few.

What do you enjoy most about being an AGS Member?

I enjoy meeting and interacting with like-mined professionals from our Industry and working together towards the betterment of our Industry by sharing knowledge and lessons learned, identifying knowledge gaps and filling such gaps by collectively and/or individually writing and disseminating papers and guidelines.

What do you find beneficial about being an AGS Member?

Personally, I benefit from knowing that I can contact other AGS members for professional advice that I can trust whether on project-specific or Industry-specific issues.

On a Company level, we find receiving and reading the AGS magazine informative as it includes current Industry updates. We also greatly benefit from participating in the AGS Conferences both for networking but also for having the chance to openly voice, share and discuss our concerns and issues with the Industry. To that end, I was extremely grateful to have the opportunity to organise and chair a panel discussion with representatives from all stake holders from our Industry including Clients, Consultants, Contractors and Academia that was aired at the AGS AGM in 2018 and included a lively audience participation. The objective of our panel discussion was about bridging the gap between designers and constructors and how do we make sure that the Engineers on site understand the importance of following the construction drawings’ specifications and what would be the implications, if, for example, they chose to use materials of lesser quality rather than the higher quality ones specified in the drawings. The panel discussion concluded that any such arbitrary replacement, which might lead to apparent cost savings, would most definitely lead to inadequate design and ultimately to an unsafe structure liable to collapse and even cause death and therefore our Industry must enforce stricter quality control and independent supervision on site.

Why do you feel the AGS is important to the industry?

Because it is run by Industry practitioners for Industry practitioners and as such it offers practical advice that is clear, unambiguous and easy to understand and follow. Or oppose to, we are always open to a good debate!

What changes would you like to see implemented in the geotechnical industry?

On the technical front, I would like to see more performance-based designs with confirmatory in-situ testing (i.e. observational method) being more widely specified and accepted by the Industry and in particular by the big Clients and Asset owners. Additionally, in order to increase the long-term resilience, value and sustainability of our assets, I would like to see a life cycle cost analysis of new or upgraded assets becoming a requirement in all tenders, in a way that would attract Tenderers’ interest and buy-in; and a way to achieve this, I believe, is by moving our Industry towards Project 13 new business model that is based on an ‘enterprise’ rather than traditional transactional arrangements. But until we adopt and embed Project 13, I would like to see more Contracts won not just on lowest pricing but on technical scoring as well as reputation scoring of the Tenderer.

On the cultural front, which is as important as the technical front in my opinion, the main change I would like to see in the Geotechnical and wider Construction Industry, is a change or rather ‘re-invention’ of individual behaviours from apathy to ownership and from routine acceptance to critical dialogue. As more and more disturbing details are coming to light from the Grenfell Tower tragedy, I think that our major focus as an Industry, should be to actively and loudly re-iterate and ‘re-enforce’ our ethical values to both practising young professionals and especially to students. Ethical behaviour, whether in personal or professional life can be taught. It is our responsibility to teach the future generations of engineers to be proud of their engineering achievements and to have a loud, firm voice when it comes to practising our professional code of conduct and our professional duty to warn. At any level. TECHNICAL EXCELLENCE must always come before any COMMERCIAL GAIN.

 

 

Article

A Candid Look at Responses to SiLC Membership Questionnaire 2019

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A previous questionnaire was issued to the membership in 2009. As part of the SiLC Marketing Action Plan (2018 to 2021), it was proposed that a revised and updated questionnaire would be issued to the membership and this was done in 2019. Some questions remained the same as in the 2009 questionnaire, but the majority were revised, for example to include questions relating to the NQMS and the role of an SQP. The response to the 2019 questionnaire was 46% of registered SiLCs (90 responses), whereas in 2009 it was 43% (57 responses).

In general, those SiLCs who responded to the 2019 questionnaire consider that achieving SiLC registration had been worthwhile and had been a key factor in their professional development. It can be noted that 81% of respondents stated that SiLC is important to their area of work with comments indicating that generally the regulatory authorities recognise its credibility, it assists commercially with winning work and from one respondent a strong belief that it puts them ahead of those that do not have SiLCs. However, there were a small number of comments which referred to SiLC as not very active, feeling stagnant and in need of increased visibility in the industry to demonstrate why it is needed and why people should want to attain it. One response was even stronger saying it costs a lot of money and is of limited value. On the other hand it can be seen as encouraging in response to one of the other questions that there has been some requirement for SiLCs in pre-qualifications or specific project work from all groups across the industry, particularly Regulatory Authorities where 47 respondents out of the total of 90 indicated a requirement, but perhaps disappointing that only 28 respondents indicated a requirement from Environmental Consultants.

The responses to the question regarding how well-known is SiLC, indicate that a strong marketing effort is needed in order to increase the awareness of all groups other than Environmental Consultants and Regulatory Authorities and, even for these, some marketing effort would be beneficial. Suggestions of where marketing is needed were Scotland, legal advisers, insurers, private developers, large landowners, NHBC and non-contaminated land professionals.

It is perhaps a little surprising that 19% of respondents said that they do not have a professional development programme. For those that do, some indicated that SiLC forms a part of that programme. Although 46% of respondents said that they do not use the National Brownfield Skills Framework (NBSF), an encouraging proportion of respondents appear to be using it, particularly for their appraisal systems. One respondent suggested that in parts the NBSF is overly complex, but did not say which parts.

According to the responses, the SiLC website does not appear to be very well used with some members using it only every so often for specific things such as the Annual Forum or not at all. There seems to be doubt as to whether the Members Area has any useful purpose and there appears to be a general feeling that the whole website needs revitalising.

Positively, 61% of respondents consider that the National Quality Mark Scheme (NQMS) will achieve a raising of standards (which was the main purpose of the scheme – by getting things right first time), with 22% saying it will not. For some it is because of the limited take-up but others consider that until it is mandatory it will not reach its full potential. One respondent is not convinced that it will lead to faster planning applications as in their experience contaminated land issues are not generally the cause of planning delays. Another respondent said that there need to be positive case studies as to how the process has speeded up planning.

A disturbing comment came from one respondent who indicated that they had been specifically asked by clients not to include an SQP Declaration because they were concerned the site would be audited and this would cause delay. In reality, there is no intention to audit sites. Audits will cover only the basis on which the SQP has signed the Declaration and whether the NQMS process has been properly followed. There would be no interaction with or hold up of the site or the planning process and this respondent should inform their clients accordingly.

Although 25% of the responses indicated that they had received a requirement from Regulatory Authorities for an SQP Declaration in prequalification or specific project work, the overall number of requirements could have come from a much smaller number of authorities. Local Authorities have a right to check reports and they need to build up their own confidence in the scheme, but by ‘getting it right first time’ in the preparation of the reports and the Local Authorities ‘signposting’ to the scheme in their guidance there is a move towards ensuring that competent people prepare reports which in turn will help raise standards. It is also encouraging to note from the responses that some requirements are also coming from landowners, corporate organisations and the legal profession with uptake continuing to grow.

The SiLC PTP are resolved to improve the website in terms of its usefulness, including links to other sources of information and organisations. More marketing of SiLC is clearly needed. As inferred above, there is a SiLC Marketing Action Plan (2018 to 2021) in place which is kept under review at each PTP meeting. This now incorporates the feedback from the 2019 Questionnaire. Further marketing of the NQMS is underway by the NQMS Steering Group which includes dialogue with Local Authorities and Government Bodies. Many thanks are extended to those who took time to complete the survey and every effort will be made to bring about the changes suggested.

Article provided by Roger Clark, SiLC Chair of the Board and approved by SiLC PTP.

Article Report Business Practice

AGS Business Practice Working Group Update

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Sally Hudson, AGS Chair Elect and Leader of the AGS Business Practice Working Group, has provided an update on the top issues the AGS Business Practice Working Group discussed at their last meeting which took place on 11th February 2020.

Promoting and Enhancing Quality and Safe Practice within the Geotechnical and Geoenvironmental Industry

The AGS continues to promote and enhance quality and safe practice within the geotechnical and geoenvironmental industry. To increase awareness, it is our goal to increase AGS membership as widely as possible throughout the industry. The BPWG is working on updating the AGS Business Plan and is monitoring the services and benefits of the Association to ensure that members best interests are represented.

Updating AGS Publications

Some Client Guides and other publications are becoming out of date and so the BPWG is driving a programme of identifying and amending key publications. Although some recent updates have been published, such as the Selection of Geotechnical Soil Laboratory Testing guidance, the BPWG are working with the other Working Groups to continue this effort, starting with some of the most popular documents such as the Client’s Guide to Site Investigations. We are also continuously monitoring our website data to assess publication popularity.

New AGS Client Guides

It can be difficult for our clients to know what the geo-professional qualifications and designations mean and how they fulfil their requirements and what value they offer. The BPWG has instigated preparation of two Client Guides to summarise the meaning of geo-professional affiliations. We have produced two draft documents, which are at review stage, one each to cover geo-environmental and geotechnical professionals. We will promote the new guidance within the AGS magazine once available to members.

As a trade body dedicated to promoting best practice within the industry, we need to ensure that the advice we provide to our members is as current and accurate as possible and reaches as wide an audience as practicable.

We are always keen to welcome new members into the BPWG and so for those interested in the governance of the AGS and wish to know how you can contribute to the BPWG, please contact the AGS Secretariat at ags@ags.org.uk.

 

Article

AGS Category Award Sponsor at Brownfield Awards 2020

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The AGS are pleased to announce that they are the category sponsor for the Best Young Brownfield Professional at the Brownfield Awards 2020.

The Brownfield Awards 2020 will be taking place in De Vere Grand Connaught Rooms in London on 8th October 2020.

Entries for the 2020 Brownfield Awards including the Best Young Brownfield Professional category are open now. Entries will close on 17th April 2020.

More information about the Brownfield Awards can be found here.

Article

“Are traditional Cable Percussion techniques really that bad?”

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Since the introduction of Eurocodes and the classification of samples with respect to disturbance, there has been much debate in the investigation industry as to the use of our traditional cable percussion sampling and in-situ testing techniques.  Whilst we at Soil Consultants are full advocates of improvements and increased quality there is, to our mind, still a relatively big unknown with regards to the benefits of high end in-situ testing techniques and/or rotary coring over the use of traditional cable percussion drilling methods.  This brief article is designed to stir some thought amongst the industry in comparing the use of ‘traditional methods’ over the more ‘improved’ sampling and testing techniques called for in EC7 and not to undo the good work put into improving quality within the industry.

Over the last few years, and major infrastructure projects aside, it is still apparent that the majority of engineering practices who specify ground investigation have little knowledge of Eurocode in relation to ground investigation, in what they are specifying, the methods available to achieve the geotechnical objectives and the scale of costs involved.  Thus, ground investigation is still all too commonly awarded on a combination of lowest cost and ignorance, which the specifiers [and by default the client] are willing to accept as ‘value for money’.  The Eurocodes are attempting to bridge this divide, but is the complexity and lack of understanding of these documents still preventing the advancement of quality and achievement of value?  From feedback in the industry [largely structural engineering practices], there appears to still be much work to do with regards to quality of investigation, quality of service and the value of ground investigation which only we as an industry can control and one which is constantly debated!

Since the publication of EC7 and its requirement for valid laboratory strength and deformation testing to only be performed on ‘Class 1’ samples, the use of the traditional U100 has been somewhat dismissed by the codes and consequently a stronger reliance has been put on SPT testing as a compliant technique along with ‘our knowledge of the geological formations’.  The use of the SPT has most likely been driven by our industry seeing this as a far less expensive alternative to rotary coring and a more practical method for congested and restricted access sites.  Indeed, this would be true as, in our experience, rotary coring averages about 200% more expensive than cable percussion drilling and few inner city sites offer the necessary access and working areas.  Pressuremeter testing also comes with a hefty price tag with an individual test averaging about £2,500 on a typical project.  The question which arises from this is: ‘Does the quality of sampling and specialist in‑situ testing provide the accuracy and reliability to justify their use and the expense?’.  The reality of this expenditure needs to be fully justified to provide confidence to the client and the design team that the results are more accurate and representative thus providing more valued engineering.  The counter argument to this being, ‘Is it better to obtain a greater data set, from say cable percussion techniques, to provide a more reliable average, which could be achieved through a higher number of boreholes and tests at significantly less expense?’

With traditional techniques, the introduction of the UT100 [thin walled sampler] has bridged the gap somewhat in the sample disturbance argument and has been rudimentarily accepted.  However, this sampling technique still does not fully comply with the requirements of EC7 due to the percussive driving of the sampling tube and it has important limitations in its practical use.  Energy efficiency measurements for SPT hammers has also been made part of the Eurocode requirement, but this still comes with problems as there is a demonstrable divide in consistency of the testing techniques and the measured energy efficiency, as the table below shows.  Arguably, and hopefully reassuringly, the majority of hammers seem to improve with age which could indicate that operators are looking after and properly maintaining their equipment.  However, erratic results are not defined by the Codes and this raises the question as to whether or not there should be some benchmarking to condemn poor performing equipment.

Table 1:  Different cable percussion hammer ratio records since 2012; colour coding represents the calibration test house.

In order to put the questions above into context, Soil Consultants have put together a data set of testing of the London Clay from our projects undertaken within central London using various sampling and testing techniques.  The data represent the ‘more traditional’ techniques adopted through cable percussion drilling as well as rotary coring and Pressuremeter testing.  In-situ CPT has not been included as we do not have access to a relevant data set at this time.  It is recognised that there are limited data available for pressuremeter testing and some of these data have been obtained from public open sources, but still relevant to the geology and geographical location.

Clearly, there are numerous arguments for and against the various techniques with regards to disturbance and testing orientation but it is acknowledged that there are flaws with all methods and the data have been presented on face value from ‘real’ projects.  In this data set, we have considered:

  • Cu derived from ‘metal’ UT100 and steel U100 sampling tubes – we are unable to segregate between thin wall and thick wall tubes although the majority of samples shallower than 15m have been obtained using UT100s
  • Cu derived from plastic U100 tubes
  • Cu derived from rotary core samples
  • SPTs, both uncorrected and corrected for N60 [Cu plotted as 5*N] and
  • Pressuremeter testing

Graph 1 shows the culmination of nearly 1,200 data points and whilst the number of points make the graph difficult to read, Graph 2 presents the envelopes of each of the data sets [lower and upper bound limits representing approximately 90% -95% of the data points ignoring anomalous low and high values].  On these graphs is also plotted ‘an average line’ which has been derived through simple visual assessment of the data set [based on the lines produced by four engineers assessing the data independently].  Whilst this is not technically a scientific average, we believe this is representative of ‘the designer’s’ approach.

Graph 1: All data points

Graph 2: Envelopes to individuals data sets

Graph 3 further simplifies the data by plotting the middle average of the envelopes and also includes the ‘average’ line from all data as a visual benchmark which, is continued through all graphs.  Graph 4 compares these data sets with the shear strength profiles for London Clay presented by Patel [1992] on 100mm diameter specimens.

Graph 3: Average profiles

Graph 4: Average profile and Patel’s envelope

Although this is not an exhaustive analysis, on face value, the following points are noted:

  • The Pressuremeter testing and Cu derived from rotary core show the widest scatter of data. Cu measured from samples obtained in metal sampler tubes also exhibits a wide scatter
  • Uncorrected SPT-derived Cu shows the narrowest envelope of all the data sets. Correcting the N value for energy efficiency, serves to further narrow this envelope
  • Whilst samples derived in plastic U100 sampler tubes gave a similar scatter in results to other ‘undisturbed’ measurement techniques, the overall strengths measured were greater, giving a higher average

 

Graph 3 plots the average of the envelopes which surprisingly produces a relatively tight group of lines, slightly divergent at shallow depth, tightening together at about 15m before diverging with depth.  Patel’s 1992 paper produced a set of data for the London Clay and shear strength measured from U100 samples [type of sampling tubes are not reported].  A refinement of Patel’s data has been undertaken with only the more central London sites being considered to provide a comparable data.  The average and lower bound envelope of this refined data set are shown on Graph 4.  The majority of the average data is seen to lie close to the lower bound line of Patel’s data, with only the measurements from plastic U100’s bucking the trend, with the results lying above the average line.  By comparison, Cu depth profiles published by Patel;1992, Skempton;1951 [U38 values corrected for 77% strength CW publication 1991] and Marsland;1974 are plotted on Graph 5.  Whilst there is a reasonable consistency with the gradients of the strength profiles, there is a significant divergence in measured Cu.

Graph 5: Cu profiles by various authors

So, what does this mean?  At this stage, it is arguable that the traditional U100 and SPT techniques are valid and show a no worse scatter than more ‘refined’ techniques.  That is not to say that any of the techniques do not have a place because this is very much ‘horses for courses’ and the overall geotechnical requirements of a particular project will dictate technique in certain circumstances.  For more routine investigations, the use of the more traditional U100 and SPT techniques, providing a greater data set could, in our view, give better value for money and a justifiable confidence in obtaining characteristic design values.  In saying this, quality of ‘workmanship’ is a considerable factor and investigation companies should ensure drilling operatives are suitably experienced and supervised along with ensuring equipment is well maintained and sampling tubes are clean.

The divergence of measured Cu profiles is proof that differences do exist in the London Clay and indeed, in our experience, the strength profiles around London do vary considerably, with some areas showing significantly weaker profiles than others; this should be accepted by the industry who should not be so quick to criticise the investigation contractor.  Design engineers, in our experience, continue to try and oversimplify this formation but, the London Clay is a variable deposit and the ground is not ‘Just London Clay’ as we hear on so many occasions.  Thus, investigation designers should be advocating a sensible level of investigation to provide a reliable and representative data set.

Whilst there is a wealth of information in the literature on the London Clay, on reflection, do we as an industry still need to put further research into sampling and testing techniques to provide the necessary confidence that routine ground investigation can provide reliable design parameters in light of the Eurocodes?

Article provided by Soil Consultants

Disclaimer: The contents of this article and the views represented within it are not necessarily reflective of the AGS as an organisation, or its Working Groups.

The AGS Geotechnical Working Group will be publishing a response to this article in a future issue of the AGS Magazine.

 

 

Article

Urgent PPE support for the NHS

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With the ongoing situation with COVID-19, the NHS urgently need the following equipment:

• FFP3 Respirator Masks
• Full Face Visors (disposable)
• Full Face Visors (reusable)
• Safety Goggles/Glasses
• Hand Sanitiser
• Full Body (Hazardous Material) Suits
• Logistics/Transport support

If your organisation is able to help, could you please contact ags@ags.org.uk to provide your details. The AGS are collating the responses of organisations who are able to help and will pass these on to a central contact.

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Update from the AGS regarding COVID-19

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With the ongoing situation of COVID-19, the AGS would like to remind AGS members of the current guidance. Businesses and workplaces should encourage their employees to work at home, wherever possible; if someone becomes unwell in the workplace with a new, continuous cough or a high temperature, they should be sent home and advised to follow the advice to stay at home for 14 days and employees should be reminded to wash their hands for 20 seconds more frequently.

The AGS are continually reviewing the situation and the decision has been made to postpone all AGS 2020 events; AGS Annual Conference (which was due to take place on 2nd April), Laboratories, Instrumentation and Monitoring Conference (which was due to take place on 15th July) and Data Management (which was due to take place on 23rd September, but has now been moved to 22nd September 2021). Further details about all three conferences will be released in due course.

For those who attend AGS Working Group meetings, we will be using remote and conferencing technologies to hold these meetings until further notice and details of these will be circulated with the meeting notification as usual.

The AGS Secretariat are currently working remotely, but we are checking our voicemail twice daily and aim to get back to you as soon as we can. We can also be contacted by email ags@ags.org.uk.