Identification and implications of the London Clay Formation divisions from an engineering perspective
File(s)
Published version
Author(s)
Standing, JR
Type
Journal Article
Abstract
Historically, engineers frequently viewed the London Clay Formation (LC) as uniform, homogeneous and rather uninteresting. Chris King's seminal work provided a much deeper insight into the characteristics of the LC and how it can be split into divisions, based on the depositional history of the formation and the microfauna present. LC water content profiles were compiled from continuous cores as part of an investigation into variations in tunnelling-induced settlements across St James's Park, allowing distinct zones to be identified. These were found to coincide exactly with the divisions identified by Chris King almost twenty years earlier. Water content profiles can be developed as part of a ground investigation and used to help establish the boundaries between King's divisions. Based on two further water content profiles from Hyde Park and St John's Wood a new methodology for locating the boundaries of the divisions, involving a trend-line for sub-Division A3, is proposed and tested, relevant to conditions in central London. In developing the method, significant differences in the elevation of the divisions between the three sites is observed, suggesting geological processes such as folding or faulting have influenced the LC along the ∼5-km length of the section.
Once the boundaries of the LC divisions are known, geotechnical engineers have a greatly improved overall understanding of the ground conditions and how the ground will respond to engineering works such as tunnelling and deep excavations. Broad engineering implications of the divisions are described and discussed, citing case histories where possible.
Once the boundaries of the LC divisions are known, geotechnical engineers have a greatly improved overall understanding of the ground conditions and how the ground will respond to engineering works such as tunnelling and deep excavations. Broad engineering implications of the divisions are described and discussed, citing case histories where possible.
Date Issued
2020-10-01
Date Acceptance
2018-08-20
Citation
Proceedings of the Geologists' Association, 2020, 131 (5), pp.486-499
ISSN
0016-7878
Publisher
Elsevier
Start Page
486
End Page
499
Journal / Book Title
Proceedings of the Geologists' Association
Volume
131
Issue
5
Copyright Statement
© 2018 The Geologists' Association. Published by Elsevier Ltd. This is an open access article available under a CC-BY Attribution Licence 4.0 (https://creativecommons.org/licenses/by/4.0/)
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/G063486/1
Subjects
0403 Geology
2101 Archaeology
Publication Status
Published
Date Publish Online
2018-09-20