A review of the geotechnical characteristics of loess and loess-derived soils from Canterbury, South Island, New Zealand

A review of the geotechnical characteristics of loess and loess-derived soils from Canterbury,... Loess and loess-derived soils cover much of Canterbury, from the foothills of the Southern Alps to the Pacific Coast. These deposits are of variable thickness, from a few metres up to 40m at the base of slopes on Banks Peninsula. In many areas the primary, air-fall loess has been reworked by slope processes to form a loess colluvium. Although primarily silty, these soils contain up to 45% clay, giving rise to low plasticity clay behaviour. These deposits are relatively dense, with dry densities of 1.6t/m3 and 1.8t/m3, hence they do not display collapse behaviour common to other loess deposits around the World. Loess and loess-derived soils across Canterbury have high dry strength but weaken rapidly with small increases in moisture content. In the wetter parts of the region, on Banks Peninsula in particular, periodic wetting leads to a variety of slope failures related to internal erosion (tunnel gullying) and rapid loss of shear strength (debris flows, soil slides and rotational failure). Elsewhere in the drier parts of South Canterbury loess deposits commonly form vertical exposures and evidence of slope instability is comparatively rare. The current understanding of the geotechnical characteristics of these deposits is based on a limited number of studies with restricted geographic extent. Thus a full understanding of regional and stratigraphic variability is yet to be established. Macroscale heterogeneities, including fissuring, development of fragipan cemented horizons and stratification, indicates that, as well as the general behaviour presented in this paper, there may also be significant local variation. In addition, the effects of soil microstructure, including bonding and particle shape and orientation, on overall soil behaviour are recognised, but have yet to be investigated in detail. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Engineering Geology Elsevier

A review of the geotechnical characteristics of loess and loess-derived soils from Canterbury, South Island, New Zealand

Loading next page...
 
/lp/elsevier/a-review-of-the-geotechnical-characteristics-of-loess-and-loess-4tIOZjt040
Publisher
Elsevier
Copyright
Copyright © 2017 Elsevier B.V.
ISSN
0013-7952
eISSN
1872-6917
D.O.I.
10.1016/j.enggeo.2017.08.001
Publisher site
See Article on Publisher Site

Abstract

Loess and loess-derived soils cover much of Canterbury, from the foothills of the Southern Alps to the Pacific Coast. These deposits are of variable thickness, from a few metres up to 40m at the base of slopes on Banks Peninsula. In many areas the primary, air-fall loess has been reworked by slope processes to form a loess colluvium. Although primarily silty, these soils contain up to 45% clay, giving rise to low plasticity clay behaviour. These deposits are relatively dense, with dry densities of 1.6t/m3 and 1.8t/m3, hence they do not display collapse behaviour common to other loess deposits around the World. Loess and loess-derived soils across Canterbury have high dry strength but weaken rapidly with small increases in moisture content. In the wetter parts of the region, on Banks Peninsula in particular, periodic wetting leads to a variety of slope failures related to internal erosion (tunnel gullying) and rapid loss of shear strength (debris flows, soil slides and rotational failure). Elsewhere in the drier parts of South Canterbury loess deposits commonly form vertical exposures and evidence of slope instability is comparatively rare. The current understanding of the geotechnical characteristics of these deposits is based on a limited number of studies with restricted geographic extent. Thus a full understanding of regional and stratigraphic variability is yet to be established. Macroscale heterogeneities, including fissuring, development of fragipan cemented horizons and stratification, indicates that, as well as the general behaviour presented in this paper, there may also be significant local variation. In addition, the effects of soil microstructure, including bonding and particle shape and orientation, on overall soil behaviour are recognised, but have yet to be investigated in detail.

Journal

Engineering GeologyElsevier

Published: Mar 26, 2018

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off