Bosai Solution ID : JBP00025

Landslide / Slope Failure Prevention Method
Landslide / Slope Failure Prevention Method which enables to preserve or
recover vegetation

HazardEarthquake Land Slide

Solution Purpose
Prevention & Mitigation Recovery

Solution Theme
Infrastructure Technology Building Technology Eco Infrastructure

Technology Subject
Dam & Reservoir Sabo Road Facility for Disaster Prevention Ecosystem-based Infrastructure＜ Downloaded from www.bosai-jp.org ＞

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Advantages
By taking advantage of these features of the measure (environment friendly), it preserves the naturalenvironment much better than the conventional method, on top of its original purpose of disasterpreventive function. It can contribute directly as “hard” interface to local disaster prevention byintroducing the slope especially adjacent to residential houses and public facilities where landslides
frequently happen. In addition, with collaboration with government and local design consultants, it also
contributes to implementing slope disaster prevention criteria suitable to local geological features.

Solution Illustrated
Stabilize slope while preserving or
recovering vegetation

NONFRAME® method is a kind of soil nailing which can stabilize slope while preserving or recoveringvegetation.
In case of stabilizing natural slope, this method can construct without cutting trees.
This method can of course be applied as well as cutting or corrupsed slope. In this case, the slope isfully covered with vegetation after construction, since this method does not cover slope with concrete.

Background＜ Downloaded from www.bosai-jp.org ＞

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EnvironmentallyFriendly Slope Stabilization Method

As an alternate solution to the concrete spray "conventional" slope-disaster prevention method, this"NONFRAME® Method" had been developed in 1996 in response to the growing needs of landscapeconservation and eco consciousness from the market. This method enables to preserve the trees
without any trees felling, grading works or covering with a concrete structure, yet to realize stabilizationof slope with its simplified structure.

Exposition of the Solution
This method, which was inspired by "trees root", consists of three major elements 1) Rock Bolt (driven
into the firm layer underground approx. 2-3m depth), 2) Base Plate (installed on its heads to stabilize
the soft and less-solid clod, weight approx. 14kg), and 3) Wire Rope (joining the base plates together as
network with 2m pitch each other).
With its excellent feature,①no need to cut the trees that are native to the slopes②possible to drastically reduce construction period and cost
③construction workable even under severe condition
This method becomes very popular in Japan with steady growth rate of construction results,
contributing keeping construction site in harmony with the beautifully landscape, which has also
induced a great deal of attention from abroad.

Achievements of Examples＜ Downloaded from www.bosai-jp.org ＞

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Right after slope failure

Right after construction of NONFRAME® method

4 months after construction, the slope had been fully coveredwith vegetation

Other References
Construction example in BhutanThis is the project with regard to Hydroelectric Project dam site in Trongsa, Bhutan. In 2015, theslope failed due to torrential rainfall and five workers were killed, even though it was originally covered
with shotcrete. Then, NONFRAME® method was installed on the corrupsed slope to stabilize the slope.
The construction area was total 5,400 sqm, however the construction finished only three months even

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severe condition, because NONFRAME® method is easy to construction even unskilled worker.
After construction, the slope has been stabilized by this method and has been covered with vegetation.

Corporate Profile
NIPPON STEEL METAL PRODUCTS CO.,LTD.
Akihabara UDX 13F, Sotokanda 4-14-1, Chiyoda-ku, Tokyo, Japan

101-0021

 Tel. : +81-3-6625-6260
 E-mail : skaji@ns-kenzai.co.jp
 Website : https://www.ns-kenzai.co.jp/english/index.html＜ Downloaded from www.bosai-jp.org ＞

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