Live poles for slope stabilization in the tropical environment
Slope instability causing landslides, a major geologic hazard, is a risk common to most regions. Among all categories of landslides, shallow slope failures which affect many hill slopes and earthwork projects are the most wide spread and pose the most costly maintenance problem. One of the soil i...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Published: |
Electronic Journal of Geotechnical Engineering
2009
|
| Online Access: | http://psasir.upm.edu.my/id/eprint/18174/ http://www.ejge.com/2009/Ppr0962/Abs0962.htm |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Slope instability causing landslides, a major geologic hazard, is a risk common to most
regions. Among all categories of landslides, shallow slope failures which affect many hill
slopes and earthwork projects are the most wide spread and pose the most costly maintenance
problem. One of the soil improvement methods that seem suitable for shallow slope failures is
the Live Pole technique. The potential value of this bioengineering technique is that it offers
an effective, economical and environmentally favorable means of combating the predicted
future increase in shallow slope instability by reinforcing slope shoulders, conducting
drainage of horizontal groundwater and acting as surface flow retardation or energy
dissipaters, to control slope erosion. Moreover the growth of live pole roots provides shear
strength enhancement and modifies the saturated soil water regime. Due to the geographical
variability in the application of this technique in different regions this study was carried out
for a tropical environment.
This paper initially describes the bioengineering technique for slope stabilization and the
requirement for selecting suitable live poles in tropical regions utilizing indigenous
woody species. These plants put through screening tests trials for the potential of the
species to propagate from large live cuttings obtained from branches of small trees and
shrubs tests, viz., tests for root and stem growth in a controlled medium under controlled
shade-house conditions with irrigation, mechanical tests and then gauge their suitability
for field trails by replanting in selected natural soils. Then results of these screening tests
found two species, namely, Hibiscus tiliaceus (Ht) and Dillenia suffructicosa (Ds) which
met the requirements for field test trials. For field tests they were installed using a twoman
auger in a close center array on selected trial slopes in the University Putra Malaysia
(UPM) campus and monitored for about 1 year. Some of these planted poles were studied
and tested after exhumation at the end of this period and the results are discussed. This
research shows that live poles are a practical and economical alternative method to
conventional techniques for shallow-seated hill slope stabilization. |
|---|