The Observational Method (OM) in ground engineering is a continuous, managed, integrated process of design, construction control, monitoring and review that enables previously defined modifications to be incorporated during or after construction as appropriate (CIRIA R185, 1999) .The OM has also been recognised by recent codes e.g. Eurocode. The OM process was introduced by Peck (1969) in his Rankine Lecture (Géotechnique, 19, No 2, 171 -187). The objective is to achieve greater overall economy without compromising safety.The method can be adopted from the inception of a project, or later if benefits are identified.

TC206 and TC220 are the Technical Committees of the International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE) dedicated to the Observational Method and Field Monitoring in Geomechanics respectively.

This mini-symposium will present three areas that they are currently collaborating on:

• Conditions that enable use of OM (speaker Professor Tony O’Brien, Mott MacDonald).
• Real-time back analysis (speaker Dr Ying Chen, Typsa).
• Field monitoring to support the use of the OM (Daniele Fornelli, Geotechnical Observations).

A further objective of the mini-symposium is to allow those that have used the OM to share their experiences. Expressions of interest to do so, should be emailed to bga@ice.org.uk by 31^st December 2023. Please include a title and a 200 word summary of what you will talk about. Those chosen to speak at the Symposium will be informed by 12^th January 2024.

Programme of Seminar

12.30 - Lunch

14.00 - Introduction to OM and TC206 - Duncan Nicholson

14.10 - Contractual arrangements for OM - Tony O'Brien

14.35 - Real-Time Back Analysis – Ying Chen

15.00 - Monitoring to support OM - Daniele Fornelli

15.25 - Questions and discussion

15.45 - Coffee break

16.15 - Presentations and discussions (these will be from people attending the conference who have registered their interest in speaking)

17.45 Close

17.50 Drinks Reception

19.00 Close

The event is supported by ISSMGE Technical Committees TC206 Observational Method and TC220 Field Monitoring in Geomechanics

Professor Tony O’Brien FREng, Global Practice Leader for Geotechnics, Mott Macdonald

Tony O’Brien is a Fellow of the Royal Academy of Engineering and a Fellow of the Institution of Civil Engineering. Tony is a recipient of the BGA’s Skempton Gold medal for his contributions to geotechnical engineering practice. He is also an inaugural Mott MacDonald Fellow. He is the Global Practice Leader for Geotechnics at Mott MacDonald Ltd and a Visiting Professor at the University of Southampton. He has provided technical leadership on several major projects across Europe, North America and the Asia-Pacific region. Within MM he leads several initiatives to support the development of modern digital tools. Tony has contributed to best practice guidance, including the ICE Manual of Geotechnical Engineering and several CIRIA guide, and recently published a book “The Observational Method in Civil Engineering.” He also works on several international committees including TC 206 (Observational Method) were he is developing guidance on contract conditions to facilitate wider use of the Observational Method.

Dr Ying Chen, Associate Geotechnical Engineer, TYPSA UK & Ireland Limited

Dr. Ying Chen is a chartered Geotechnical Engineer and researcher with over 17 years of experience in a wide range of geotechnical design and construction activities for railway infrastructure, urban area basements, and high-rise building foundations. Major infrastructure project experience includes HS2 /Crossrail in the UK, Metro project in Hong Kong, Shenzhen China, and Doha. She is now leading the C2C3 Geotechnical design for Earthworks at Aylesbury Area as an Associate Geotechnical Engineer with TYPSA UK & Ireland Ltd. After her Ph.D. at the University of Cambridge, on the “Application of the New Observational Method on deep excavation retaining wall design in London Clay”, she was nominated as a member of ISSMGE Technical Committee (TC) 206 – Observational Method, continuing her research work on the Machine Learning back analysis. The collaboration with SAALG Geomechanics successfully trialled the innovative ‘DAARWIN’ tool on the HS2 project, proving the 'real-time' back analysis in a real construction environment. The success of this trial led to the Observational Method modification proposal on tunnel portal construction at the HS2 project, to optimise the construction program and achieve time and cost savings.

Mr Daniele Fornelli, Associate Technical Director, Geotechnical Observations Limited

Daniele is an Associate Technical Director for Geotechnical Observations Ltd., responsible for the technical aspects (including data validation, analysis and interpretation) of monitoring schemes across the UK. He is a Chartered Civil Engineer, with more than 10 years experience in Instrumentation and Monitoring. He has been involved, as a contractor and consultant, in a number of complex schemes both in the UK and overseas, including: tunnelling in urban areas, ground treatments, deep excavations and large scale trials. As a Geotechnical engineer, his passion for analytical and numerical modelling has complemented his deep interest for I&M, allowing him to keep a scientific and data-driven approach to complex data interpretation and back-analysis problems. Daniele is the leader of the AGS I&M Working Group.