Site Preservation and Disaster Recovery Using KODOBOKU Technology

C-TECH CORPORATION

Publication date	September 1, 2022 (Posted on October 16, 2024)
Sector	Natural Disasters / Coastal Areas / Industrial and economic activities

Company Overview

Climate Change Impacts

In recent years, localized heavy rainfall has been increasing due to the effects of climate change, and rainfall has caused the erosion of topsoil or landslides in the slopes of mountainous areas.
Mainly in western Japan, tree damage by Japanese sika deer has been increasingly prominent, and the failure of trees to grow has caused further erosion of the topsoil, resulting in the progressive degradation of forests and mountains.

Adaptation Initiatives

We have developed a variety of technologies as “KODOBOKU technologies” to prevent slope collapse due to heavy rainfall on slopes where transmission towers are installed and where it is difficult for vehicles and heavy machinery to enter. The materials used in this technology are all lightweight, can be transported by hand, and are highly durable. We have also developed a technology that simulates the trend of surface flow on slopes, facilitating construction that combines individual technologies (①~④ below), depending on the site environment.

1. ① Stone bag (Fig. 1) (Note 1)
   Stone bags laid on slopes prevent erosions by rainwater by dispersing and controlling the force of flowing rainwater. They can also be used for site preservation, such as anchoring floating stones, securing scaffolds on soft ground for escape routes and patrol paths, and installing stairs on slopes.
2. ② Steel soil retention (Fig. 2) (Note 2)
   They can be used to prevent soil erosion caused by rainwater, and maintain the underground infiltration flow and reinforce the vegetation which will stabilize the ground surface.
3. ③ Rainwater guiding mat (RL Mat) (Fig. 3) (Note 3)
   Rainwater guiding mats with three-dimensional waive shaped patterns prevent the erosions by dispersing and draining rainwater to control the flow.
4. ④ Planting asebi (Japanese andromeda) for damage control (Note 4)
   Asebi is an evergreen shrub native to Japan and is widely distributed in the west area from the Kanto region along the Pacific Coast of Honshu. It is a deer resistant shrub, and is easy to manage after planting. Planting asebi on a site can prevent slope collapse due to damage on the vegetation caused from feeding.

We are also conducting a joint research project in Miyazaki Prefecture with the Fukubayashi Laboratory, Department of Civil and Environmental Engineering Program, Faculty of Engineering, University of Miyazaki to quantitatively verify the effectiveness of “KODOBOKU technologies” in controlling surface collapse and sediment runoff.

Effects / Expected Benefits

Our “KODOBOKU technologies” expected to be useful in various situations including slope protection, collapse countermeasures, emergency restoration after disasters, forest conservation, and reforestation, because it can be used in combination according to the site and condition, and does not require temporary constructions or work roads.
This technology also won category A (Ingenuity in Maintenance Practice On-site) of the Fourth Infrastructure Maintenance Awards by the Ministry of Economy, Trade and Industry (January 2021).