The AGS webinar on The Development of a Degree Apprenticeship took place on 23^rd March 2022. 248 people registered to attend the webinar and 90% of attendees would recommend the webinar.

This webinar saw Dr Nick Koor (Reader in Geological Engineering, University of Portsmouth (School of the Environment, Geography and Geoscience)) and Paul Roberts (Regional Director at AECOM) discuss the worrying trend of how the number of students enrolling on Geoscience courses at university has declined over the past six years. The webinar was chaired by AGS Chair, Sally Hudson.

The event also covered the development of a Degree Apprenticeship in Geoscience. This was spearheaded by UGUK at a kick-off meeting in November 2021. A Trailblazer Group for the Degree Apprenticeship in Geoscience has now been formed and is being chaired by Paul Roberts. The group are currently in the occupation proposal stage, with the course is likely to start in 2024.

If you missed this webinar, the replay is now live and available for view on the AGS website for free. Click HERE to view the replay and download the speaker presentations and file handouts.

The Ground Forum Undergraduate Mentoring Programme is currently in its second year and is in the process of reaching out to students for the 2022/23 intake.

The aim of the programme is to support the goal of increasing the number of currently underrepresented groups within the industry, as well as retain those already within it. The programme is financially funded and supported by members of the Ground Forum including AGS, FPS, BDA, PJA, British Geotechnical Association, EGGS, IGS UK, IOM3, GSHPA, British Geomembrane Association, British Geophysical Association and NSGG.

Universities involved in the current intake include University of Portsmouth, University of Hertfordshire, University of Bradford, Coventry University, Loughborough University, Imperial University, Trinity college, Dublin and University of Plymouth.

The Ground Forum are looking to reach out to further universities by promoting the programme to universities through guest lectures.

The students on the current intake are studying qualifications including Civil Engineering, Civil & Environmental Engineering, Civil & Structural Engineering, Architectural Engineering, Engineering Geology & Geotechnics, Geology, Palaeontology and Physical Geography & Geology from 1^st year to postgraduate.

The programme involves being matched with a mentor for the duration of the programme, two workshops on interview and CV skills, a LinkedIn group to communicate with other mentors and mentees and a two week work experience placement.

If you are a student, who would be interested in joining the programme for the 2022/23 intake, please click here or scan the QR code on the flyer for the application form.

If you provide guest lectures in universities and would like to promote the programme to students, please email gforum@ground-forum.org.uk for further details and a copy of the flyer.

The Association of Geotechnical and Geoenvironmental Specialists (AGS) is pleased to announce that it is partnering with geotechnical training specialists, Equipe, to deliver the 2022 AGS Annual Conference at Geotechnica.

Following several successful annual events delivered from the Birmingham Motorcycle Museum, the AGS is delighted to announce that this year’s Annual Conference will take place at Geotechnica 2022, the UK’s premier geotechnical conference and exhibition.

The AGS Annual Conference (formerly known as Members’ Day), will be held on Wednesday 6th July 2022, at the Warwickshire Event Centre. A new industry Safety Summit will be held the following day, on Thursday 7^th July.

The Annual Conference is the AGS’ flagship event and will provide an update on the work of the AGS and its eight Working Groups from the past 12 months. The event will also feature six technical presentations, delivered by industry-leading specialists on key hot topics. This full day event is free to attend. The speaker line-up is expected to be revealed in the coming weeks.

“The AGS Annual Conference is an established, staple date in many industry stakeholder calendars, and combining the event with Geotechnica provides sponsors, exhibitors and attendees an invaluable opportunity to get the best of both experiences in a single, focused event,” explains AGS Chair, Sally Hudson. “We saw this as a great opportunity to get even more eyes on the invaluable work and service that the AGS provides for its membership and the wider geotechnical and geoenvironmental community. The Annual Conference is a great snapshot of what the Association is all about; addressing critical issues, education and improving standards across the board. It also offers an excellent opportunity to celebrate the achievements and successes of our members. Combining the Annual Conference with Geotechnica not only provides benefits for attendees, but it also helps us to promote the AGS to an even wider audience.”

Marking a change from previous Geotechnica events, 2022’s offering will be an indoor-only exhibition, with outdoor exhibitions returning in 2023 before maintaining a biennial indoor/outdoor model. It is hoped that Geotechnica 2022 will bring together all corners of the geotechnical community and encourage further collaboration between Clients, Consultants, Contractors and Suppliers to best meet the industry’s ever-expanding expectations, needs and growing influence on the construction market.

“Geotechnica 2022 will literally bring the industry together under one roof and will appeal to the whole supply chain from Client to Supplier,” continues Julian Lovell, Managing Director of Geotechnica organisers, Equipe Group. “The event will host the AGS Annual Conference on day 1, a Safety Summit on day 2 and the very successful Early Career Geopractitioners conference will also return. The 2022 event will build on its already considerable success of creating a unique mix of trade show, conference and networking. We really hope that everyone involved in our community will be interested in attending, either as a sponsor or exhibitor, or simply visiting to engage with all represented stakeholders.”

Geotechnica 2022 is planned to feature a full product and service exhibition, with the UK’s leading geotechnical specialists, suppliers, contractors, laboratories and associated services all being represented. The Early Career Geopractitioners Conference will also provide an invaluable opportunity for new entrants to the industry to glean technical advice and training from some of the industry’s most experienced and knowledgeable practitioners.

The event will be entirely free to attend for visitors, with over 65 exhibition spaces available for companies wishing to communicate, promote, network and learn at the UK’s premier geotechnical conference and exhibition. Full event information can be found at: www.geotechnica.co.uk.

To register for the AGS Annual Conference and Geotechnica, please click here.

For information about exhibiting, please click here and for information about sponsoring, please click here.

In 2013 reports of illness among residents in Gorebridge, Scotland led to the discovery that carbon dioxide was entering newly-built homes. A total of 22 residents from an overall total of 165 in the affected area were reported to have contacted healthcare services between September 2013 and September 2014. The most common complaints were headaches, dry coughs, dizziness and anxiety. The town is in a former mining area and the development was underlain by old mine workings with shafts present nearby.  Subsequent investigations led to the residents being re-located and 64 houses being demolished.  Whilst it is arguable whether demolition was appropriate or necessary, a subsequent study by the Scottish Government recommended that consolidated guidance was required for the industry on the investigation and assessment of mine gas risk.

More recently one of the authors has been involved in a site in Northumberland which has very similar circumstances; reports of illness that are symptomatic of exposure to high levels of carbon dioxide followed by investigation and discovery of gas inside the properties.  However, in this case a robust investigation followed that determined the points of gas ingress to the properties.  This found that the gas was only entering via open, unsealed ducts containing water pipes (also likely the case at Gorebridge).  Once these were sealed the gas ingress stopped and the properties were shown to be safe.

In response to the recommendations in the Scottish Government report, in late 2021 CL:AIRE published its Good practice for risk assessment of coal mine gas emissions.  The guidance draws on the experience of the authors who all have a good understanding of the issues that caused the Gorebridge incident.  It provides a pragmatic but robust framework on which to base a mine gas risk assessment.  It is important to note that to those that undertake mine gas assessments that they should not just go straight to the Decision Support Tool in Figure 13.1 without reading and following the advice in the rest of the guide.  In particular there are other key reference documents that must be read in conjunction with the guide, as explained in Section 7, Useful Information Sources.

Key take points are:

• Mine gas risk assessments and mitigation design should be carried out by ‘competent persons’ as defined in the National Planning Policy Framework (NPPF) in England and equivalents in the devolved governments.
• It is important to understand the different methods of working coal, the effect this has on the likely presence of a mine gas hazard being present below a site and the corresponding risk of emissions into buildings. At the very least, CIRIA Report C758D (CIRIA, 2019) is considered to be essential reading for anyone undertaking mine gas risk assessments.
• As with any other ground gas assessment development of a Conceptual Site Model (CSM) to avoid an incomplete mental model of the problem is a vital part where there is a source of mine gas, as well as its use in the interpretation of any gas monitoring data.
• Risk assessment using the gas screening values and the ‘points system’ in BS 8485 on its own is not likely to be appropriate where there is a risk of mine gas emissions on sites with complex CSMs or where mass advection of soil gas could occur. Detailed quantitative assessment of gas emissions may be necessary.
• Finally, risk assessors should consider the effect of foundation construction and other buried infrastructure on migration pathways and the integrity of any barrier layers. The risk assessment should be revisited once all below ground, foundation and slab designed has been fixed to make sure it is still applicable.

At the site in Northumberland an old, unsealed borehole or grout hole is considered the most likely migration pathway for the gas to have reached housing.  It is vital that after the site investigation or gas monitoring is complete that any boreholes, probeholes, grout holes or wells are decommissioned and sealed to prevent them acting as migration pathways for mine gas. advice on the expectations and requirements of borehole decommissioning has been provided by The Environment Agency and SEPA. In this respect the co-ordinates of all holes should be accurately recorded on the logs. The use of plastic liners that are left in place in grout holes are the major concern for gas migration as they can leave a void around the outside that can form a pathway.

Potential areas of uncertainty in mine gas risk assessment and the effects of future changes in climate should now also be considered. A mine gas risk assessment should be awarded similar resource and effort as would a mineral risk assessment.  It is important to recognise that this requires site specific investigation and assessment for relevance and credibility.  Generic statements are not deemed appropriate and although a precautionary approach should be applied to any risk assessment, this is not an excuse to invent hypothetical or extremely unlikely hazards or consequences. Bias can occur when there is a desire to be cautious, prudent or conservative in estimates that may be related to harmful consequences. Yet such can also lead to the  delivery  of unnecessary and costly remedial intervention despite a  low probability risks being present. Transparent critical thinking is required in reporting that evidence based.

The CL:AIRE guide can be found here.

CL:AIRE will be running training courses throughout 2022 on how to apply the advice provided in the Guide.  These will be delivered by the authors of the guide so will you get a first-hand understanding of the theory and thoughts underpinning it.

Article provided by Steve Wilson (The Environmental Protection Group Ltd) and Alex Lee (WSP)

Image credit to Amy Juden, EPG Limited

Full Name: Rob Terrell

Job Title: Senior Geotechnical/Geo-Environmental Engineer

Company: Ground and Water Limited

What is your background and how did you end up working within the geotechnical industry?

Following 4 years of University study, I embarked in a career in geotechnical and geo-environmental engineering at Ground and Water. In 2016, I started as a field technician, where I learnt the physical and practical aspects of the geo-engineering industry. One year on, I transitioned to the engineering career path, applying and developing my knowledge of soil mechanics and chemistry, before steadily progressing to the senior geotechnical/geo-environmental engineer I currently am.

What does a typical day entail?

Whilst devouring some muesli, I refamiliarize myself to my project spreadsheet and prioritize tasks. Whilst undertaking the reporting, modelling or sample assessing I prioritise, I also make sure to check in with my mentees, technicians and site workers, providing guidance when needed. Another part of my day is guaranteeing client satisfaction, whether that be from hitting deadlines, providing project aftercare, or ensuring project-specific requirements are accounted for.

Within your career to date, what is your greatest achievement?

My greatest achievement to date would be an ongoing and constant one; watching my mentees and colleagues develop and learn their craft, becoming competent and assured geo-engineers. I really enjoy transferring and sharing knowledge and experience to my colleagues, which is an integral part of my senior role within the company.

What is your favourite part of your job?

Being in a small (but swiftly growing) company, there is a real family feel and my colleagues are genuine friends who make the days more enjoyable. I am grateful that they support me not only at work, but outside of work also.

What are the most challenging aspects of your role?

The industry is fast paced and can be very demanding at times, which can often take its toll; luckily, I have a good team around me and a proactive mindset which mitigates this stress greatly. Comfort food also helps!!

If you could do it all over again, would you choose the same career path for yourself? And if not, what would you change?

I believe it is beneficial to undertake a technical/site based role so that you fully understand the basics as well as the importance of detail. Then when you are an engineer, you know what is required during site investigations at the earliest opportunity. Therefore, I am happy with the path I took.

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

I am part of the geotechnical working group as an early career member. Within the group, I am part of a sub-committee working on developing guidance and standards regarding underpinned basement foundations. I am also co-writing an article on how site investigations and sampling can be more sustainable.

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

I’ve always believed collaboration is key to success, and by bringing together specialists from across the UK, we can all learn from each other and encourage sustainable change within the industry.

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

I believe that there is great potential for the geotechnical industry to become more sustainable, whether it is small factors like using reusable/recyclable material, to larger factors like engineering design. A global mindset shift is required to ensure we have a healthy world in which to thrive on.

Lastly any advice or words of wisdom that would you give someone who is either considering this type of job or who are progressing towards chartership?

Work hard, but never forget that rest is equally important and a healthy work life balance is essential. A stressed and overworked brain will do nobody any good. All work and no play etc..!

The appended table provides an extract from the analytical results of a Waste Acceptance Criteria test (WAC) from an anonymised site. Such testing can be expensive and yet the need for such testing continues to remain, at times, misunderstood by both clients and consultants. Indeed, there remains a fundamental degree of confusion as to the purpose of WAC testing, even 15 years after they were first introduced under the UK implementation of the Waste Framework Directive. WAC testing is only used to determine how a waste will behave once it’s buried in a landfill. This is carried out primarily through analysis of leachate derived from that waste during laboratory analysis. It cannot be used to determine whether a waste is hazardous or not.  Whether a waste is hazardous is dependent upon the Hazardous Waste Regulations and is established by reference to the Hazardous Waste List of the European Waste Catalogue (EWC) on the basis of the absolute amounts present in a substance.

To reiterate, WAC testing is inadequate on its own for allowing the disposal of soils. The same material must also be tested for total concentrations which should be used first to define its hazardous characteristics or classification. Logically, WAC testing should only be considered if the soil is known or very likely destined for disposal of to a Licensed Landfill. Consequently, in the interests of sustainability, reducing costs, reducing sample jars, laboratory time and equipment, we should not by default schedule WAC testing during a typical site investigation. Submission of waste soils to a landfill accompanied only with WAC results could also result in refusal to accept. Refusal cannot only offend but can also be very costly and embarrassing.

To restate the point, WAC tests are a secondary layer of classification emplaced to ensure that as a waste material they are suitable for placement and compliance within the target landfill without generating a future leachate problem at the same receiving landfill. The test is required only after waste classification has defined its hazardous properties and only determines whether the waste is suitable for deposition at an Inert, Stable Non-Reactive or Hazardous Waste landfill. There is nothing much else you can do with WAC test results.

As already noted, the primary classification of waste soil as Hazardous or Non-Hazardous is made using the results of analysis of total concentrations of the hazardous substances that could be in it, not the amount that potentially comes out after WAC leachate testing. This requirement for solid analysis derives from the Waste Framework Directive (enshrined in UK law) and is the process used to define the absolute hazardous properties that a material might have. These properties determine at a very fundamental level as to how you must treat it as a material for disposal, handling and storage purposes including the application of the Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations to even get it off-site.

The list of potentially hazardous substances for which you should be analysing should be based on the desk study and the ground investigation findings. Indeed, most of the data required for primary classification is often already available from the initial ground investigation without further need nor cost, so you can get twice the value for your analytical sample costs. The data you need to characterise a waste may already be in your reports, hopefully stored in an AGS4 or similar format so you can forward it directly to your waste contractor for characterisation. If in doubt during the investigation phase as to what you might actually need to categorise, think ahead so as to ensure that you have enough primary data for a waste contractor to classify the soil at a later point. There is no need to schedule expensive WAC tests when often they are not needed nor assume on the occasion of landfill disposal that they alone will satisfy the expectation of the receiving landfill. If in doubt, ask an expert and think the process through.

If this monologue still leaves you wondering, there is a great video about tea bags here https://www.linkedin.com/feed/update/urn:li:activity:6686937368596885504/

The AGS published excellent practical guidance in 2019 “Waste Classification for Soils – A Practitioners Guide” https://www.ags.org.uk/item/ags-guidance-on-waste-classification-for-soils-a-practitioners-guide/

Article provided by Marian Markham (Land Quality Associate Director at Jacobs) and Chris Swainston (Principal Environmental Engineer at Soils Limited)

The process of returning to work offices in mid-2021 following a year and half of working from homes has prompted another (probably 4th time in 32 years) major purge of our company “hard” technical libraries.  Over the past 18 months I’ve personally struggled in not having my paper “hard” technical library available to me, and in particular those proven “old” papers that we refer to time and time again.

This most recent major purge made me reflect that the digital business world that we work in is not perfectly suited to learning, remembering and using the lessons that our forebears took the effort to write down and disseminate.  Of course, some technical papers can be found “digitally” in pdf format somewhere on the internet, some legally accessible, albeit surprisingly costly.  However large hardback volumes of proceedings from e.g. the international conferences of the 1970s and 1980s etc. aren’t so easily accessible online.

In parallel I reflected on how I learned much of my own personal “geotechnique” over several decades, and I reflected that a lot of it came from sitting on floors in various company, Institution and university libraries in between bookshelves, seeking out and reading papers in Géotechnique, QJEG, Canadian Geotechnical Journal, the numerous ASCE proceedings, Soils & Foundations to name but a few.  A positive by-product of that was the list of further references in all those papers, along with the other papers in whichever volume I was looking at, which then took me off on other journeys of discovery.

Therefore, in the spirit of prompting and promoting the dissemination of lessons learned long ago, this paper is the first in hopefully a series of articles on technical papers that experienced geotechnical practitioners rely on and return to over and over.

The following is a selection of 6 of my “go to” papers, which have been most useful to me over 3 decades plus of geotechnical engineering practice, mainly in design, along with some notes of why I find them useful or what they mean to me.  These are Technical papers, from conferences and proceedings – not books, not technical reports.  They are the ones that are in the folder immediately to hand (pre-COVID), and are well worn and have been stapled and sellotaped together several times.  They have personal annotations over figures and highlighter shading of key paragraphs.  I have deliberately limited myself to only 6 papers – it would have been easier to have 12 or 22 or more ! As a result I haven’t included a number of great papers on for example, railway track and sub-grade engineering from India, Japan, and the US which were vital in the early 2000s when the UK were designing and constructing both light rail systems without a modern UK track-bed and subgrade design method – if you are interested, then research the papers of Gerald Raymond, J T Shahu, and Li & Selig.

I add the caveat I am not including any of the Rankine Lecture papers – they are well known, free and online https://www.britishgeotech.org/prizes/rankine-lecture .  It was nice re-reading the list of Rankine lecturers again whilst preparing this article.  Sutherland’s 1987 lecture on Uplift Resistance was my first during my industrial year when I was encouraged to attend by my work colleagues.  I regret missing Peter Vaughan’s in 1994 while working away, but particularly memorable and useful lectures to me were those by Poulos 1989, Burland 1990, Simpson 1992, Clayton 2010, Lacasse 2015 and Jardine 2016. My personal close winner is the still unpublished David Hight lecture in 1998.  I look back at those papers in particular and note however that my preferences might be biased by being lucky to have worked alongside those authors at some point in my career, or used their work for my own research.  If you haven’t read the Rankine Lectures, I encourage you to do so, and those might be interesting ones to start with.

In concluding, it occurred to me that the following 6 papers appear to be the source of widely used design charts and rules of thumb, and I then wondered how this non-digital knowledge and “rules of thumb” will be used in “digital” and AI-influenced designs of the future.  And that reinforced my resolve to start off this series of papers.

“Fraser & Wardle”  (1976) “Numerical analysis of rectangular rafts on layered foundations” Geotechnique 26 No 4 pp613 – 630

This, along with my Craig “Soil Mechanics” 3^rd Edition textbook is probably the most “re-sellotaped” in my collection.  The paper is primarily focussed on design charts derived from 1970s numerical analyses for the design of uniformly loaded rafts for settlement and bending moment, taking into account the relative stiffness of the raft and the ground.  Graphs of influence factors, settlement correction factors and bending moment influence factors are simply presented for a variety of relative stiffnesses (“Stiffness factor”) across various geometries of raft.  The results are extended to address infinite depth or multi-layered ground, and herein lies one of the “golden nuggets” of this paper.  The combination of Stiffness Factor of the raft/soil system and varying soil stiffness with depth allows the user,  probably after several uses of the method, to really get an understanding of the operating zone of influence beneath a slab, and what depth is most important to best characterise accurately by investigation to optimise settlement and bending moment, and hence slab thickness.  This acquired knowledge is vital to good geotechnical and structural engineering design.  The method and learning substantially avoids the need for complex numerical modelling, or at least allows one to challenge the predicted behaviours in numerical models.

James Penman extended this work in the early 1990s in his Imperial College MSc thesis using axisymmetric FLAC analyses, and this has proved to be useful for e.g. buried reservoir structures at the column/slab interface where moments and shears peak and change direction, and are therefore key elements of design of those structures.

“Burland, Simpson & St John” (1979) “Movements around excavations in London Clay”. Proceedings of the Conference “Design Parameters in Geotechnical Engineering” BGS London Vol 1pp 13 – 29

This is a good and comprehensive paper discussing  real ground movements and the factors controlling movements around deep excavations.  The paper presents back analyses and provides information on applicable operating ground design parameters, and provides a good summary of the real scale of movements to be anticipated.

What is particularly useful is the discussion around K₀ and earth pressures.  The Initial K₀ for embedded wall design can be a highly dominant factor in ground movement predictions, and values determined from e.g. Self Boring pressuremeters certainly, and to a certain extent from suction measurements on thin wall samples, can be very high.  The paper includes a very useful figure presenting horizontal and vertical effective stress and K₀ during unloading and reloading.

“Burland & Coatsworth”, (with acknowledgement to Burbidge) (1987) “Estimating the settlement of foundations on sands and gravels”  Proceedings  Int. Conference on Foundations and Tunnels, London, 24–26 March 1987 Vol 1, P1–6.

Marcus Burbidge’s original MSc thesis and his subsequent paper with Professor Burland was based on a very large number of case records of settlements of foundations, and this led to a relatively simple empirical basis for settlement prediction, and one which reflected reality whilst predicting settlements much less than many common approaches.  Coatsworth extended this original study with additional case records.

It is noted that for the most part, SPTs from the original case records were NOT corrected for overburden pressure, that the dominating depth of influence was <breadth of foundation, and that SPT be averaged only over that zone.  A simple Compressibility Index is derived and then used to determine settlements “at the end of construction”.  A really interesting and useful aspect of the method is that it also predicts long term (30 years) settlements, with these being larger than the end of construction settlements.  Many books tell you that settlements on granular materials are (substantially) complete at end of construction, yet the empirical results suggest that total settlements at 30 years are 150% for static loads, and 250% for fluctuating loads.

Apart from this really interesting facet, the great advantage of this empirical method is that one doesn’t have to try and work out what value of E’/N is applicable to a foundation load case, noting that the range of E’/N for granular foundations of varying load intensity is massive ! (see CIRIA R143 Clayton (1995))

(Note – you may wonder why I use the Burland & Coatsworth paper rather than the original Burland & Burbidge paper ?  Well, for daily design I only need the few graphs and equations which are summarised neatly on one single page in the B&C version, and hence that’s the one I reach for in my folder of useful papers!  But please do go and dig out the original B&B paper in the 1985 ICE Proceedings which has a lot more useful information and background to the method.)

“Bica & Clayton” (1992) – “The preliminary design of free embedded cantilever walls in granular soil” Proceedings of the Retaining Walls conference, ICE, Cambridge University, July

Adriano Bica’s PhD at University of Surrey was on free embedded cantilever walls in granular soils, and this paper to the Retaining Wall conference presents a number of highly useful design charts for depth of embedment and bending moment for embedded cantilever walls, based on model wall experiments  The experimental values of depth of embedment at failure were normalised and presented in design charts which are excellent and simple tools for very quick preliminary design without having to do WALLAP / FLAC etc. analyses.

“Black & Lister” (1978)– “The strength of clay fill subgrades : its prediction and relation to road performance” Proceedings of the conference Clay Fills, ICE London pp 37 – 48

This useful paper is a great summary of the relationships between CBR and shear strength for clays  – coarse granular soils are generally far less of an issue because their CBR is much higher, hence it is the low strength and plastic materials that cause us most concern.  As UK pavement design standards (e.g. the DMRB etc.) have ben updated and superseded several times, it is often difficult to know where the background and science supporting those methods lies.

“Boscardin & Cording” (1985) – “Building Response to excavation induced settlement”

Journal of Geotechnical Engineering,  ACSE 115 No1 January

There is a lot more in this excellent paper than just 2 key figures and 1 useful table, but those are what I reach for first . Figure 4 provides a chart of Horizontal Strain vs Angular Distortion and plots zones of differing damage showing the inter-relation and importance of these 2 factors in determining how much settlement is too much.  Figure 11 provides useful definitions of various different terminology used, which is helpful when speaking to asset owners and other engineers.  Table 2 provides the very widely used Damage Classification by description or by crack width.

In concluding, it occurred to me that these 6 papers appear to be the source of widely used design charts and rules of thumb, and I wondered how this non-digital knowledge and “rules of thumb” will be incorporated into “digital” and AI-influenced design approaches of the future.  And that reinforced my resolve to start off this series of papers, and hopefully will prompt other readers and practitioners to propose their own similar sets of “desert island geotechnical papers”.

Article by Steve Everton, Jacobs