GreenPro. Promotion of an Innovative and Green Slope Protection System

KoEF 03/2019

General Project Information

© Prem Bahadur Thapa

Cooperating countries: Nepal and Austria

Coordinating institution: Assoc. Prof. Prem Bahadur Thapa, Tribhuvan University

Partner institutions: Univ.-Prof. Wei Wu, University of Natural Resources and Life Sciences, Vienna (BOKU)

Project duration: 1 November 2020 - 31 October 2024

Abstract

Number and intensity of natural disasters have been increasing in mountainous countries like Nepal and Austria. In a developing country like Nepal the intensity of natural disasters are even more due to weakly monitored infrastructure development activities such as construction of roads, building irrigation channels, telecommunication towers, hydropower projects etc. Almost every family living on hills and mountains is vulnerable to landslide, flood, debris flow and earthquake induced landslides disasters. Due to the increasing number of landslide incidents every year, it has become routine or customary to bear the loss of hundreds of lives and property worth millions of dollars due to landslides and floods. In order to mitigate the human induced and rainfall triggered natural disasters, it is necessary to implement appropriate preventive and curative measures against slope failure, soil erosion and flooding.

Soil nailing is an economical and efficient reinforcement technique used as a remedial measure in unstable natural slopes or as a retraining structure for excavated slopes. In comparison with other retaining/protection structures soil nailing permits to reduce the excavated/fill soil volume, saving construction materials and realization time. There are two main concerns about the application of soil nailing, first is in its analysis and design and second is about the use of materials. In order to make an innovative construction practice and to make it more cost effective, environment friendly and sustainable, a right choice of facing and an appropriate design of soil nails are very important. Regarding the analysis and design of soil nails several national codes or guidelines exist. But the role of facing elements in controlling the deformation of excavated front or the overall stability of slope is not yet completely understood (Sanvitale et al, 2013).The stiffness of facing strongly influences the characteristics of tensile force distribution, such as for a slope of two lateral segments, the tensile force at the connection (nail head) of nail with facing, and the location of maximum traction on the soil-nail-facing system. (Sanvitale et al, 2013). Most of the conventional soil nailing with shotcrete, precast concrete or metal facing elements are generally costly and do not offer a “Green” slope. The flexible facing elements do offer some possibilities to grow some plants on the slope but have some disadvantages e.g. bulging or punching at nail heads and are not suitable to control surface erosion and local shear failure. In the above context, the soil nailing system with semi-flexible 3-dimensional galvanized steel mat (popular as KRISMER® system in Europe) is a high-quality construction system which has proved itself one of the best solutions to stabilize slopes and embankments. Although, the functioning of soil nailing with semi flexible 3D mat has been verified by different experiments and real site assessments, the actual behavior of soil nail installed in combination with 3D mat system still is unknown. The main goal of this proposal is intended to investigate the stress distribution in nails, nail heads and the deformation pattern of soil nailing with semi flexible 3D mat system under real site situation by model construction, observation and assessment on a real site, laboratory experiments on soil nail models and by numerical simulation. Beside these, it is intended to verify the applicability and sustainability of the slope protection system under extreme environmental conditions like heavy rain during Monsoon season and following dry periods. The proposed project should also prove that the system is ready for its widespread use around the globe as an environmentally friendly and green slope protection and river erosion control system.

Contribution to Sustainable Development

In line with the objective of the call program, the proposed project is an application oriented cooperative research project. This project will contribute the southern partner (Nepal) in solving the challenges in local level to deal with landslides and soil erosion related problems through the application of environment friendly and sustainable slope protection technology.

The project directly deals with the SDG 15: Life on land1, which urges to protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss. Since the focus of this project is protection of slopes and soil erosion control which directly address deforestation, desertification and degradation of land. The proposed green technology for slope protection and erosion control also contributesto terrestrial ecosystems sustainable development.

Furthermore, the proposed project willstrengthen an academic partnership in cooperative research in the field of sustainable development and environment protection in Nepal. The project will promotethe application of environment friendly and sustainable technology for the protection of slope, soil erosion control and maintain the biodiversity.

This project will also help for the sustainable development and poverty reduction in developing country by exploiting local knowledge and resources in green and environment friendly construction techniques in rural areas. The planned objectives of the project are fully aligned with the aforesaid thematic focus area of the research cooperation program. The activities like exchange of lectures, involvement of academics and students in research, review and updating of teaching materials and joint Master and Phd theses are related with the capacity development and quality improvement in higher education.

Whereas the activities like gap analysis on the existing course contents and teaching materials, study visits, guest lectures and laboratory model experiments on application of an appropriate technology will help for the improvement of quality of teaching staff and academics. The project is designed in such a way that there will be an active involvement of all team members during various project activities. It is planned to have series of guest lectures in each exchange visits, where academics and students (future researchers) will take part. This will contribute to transfer theoretical knowledge to solve practical problems. The project activities such as joint Master thesis supervision, exchange of study visits and guest lectures are planned to have a strong exchange of knowledge and skills between partners. The activities planned under this project will certainly help to enhance the capacities of the teaching staff and academics. In addition, the management capacity of the southern partner will be improved by managing different project activities. Provision of guest lectures will help to improve the presentation skills whereas joint publication of research papers will help to enhance the writing skills of the academics. These all activities will finally improve the institutional capacity of higher education and research in targeted country.

 

1Take Action for the Sustainable Development Goals - United Nations Sustainable Development