JICA Financial Cooperation Implementation Department; To prevent road rutting - JICA's experiment contributes to improving the quality of roads in tropical regions-

JICA's aid for road

Roads play a significant role as part of essential and basic social infrastructure for livelihood and economic activity.

JICA has supported numerous road developments and aimed to build foundations that improve user safety and amenity and support economic activities in developing countries.

However, not only in JICA's road project but also in other projects for tropical region, damages such as rutted roads, often is identify as a problem on the pavements after frequent use of them.

JICA published "Road Pavement Handbook For JICA Grant Aid Project" (February 2020), the results of basic research about the improvement of road's resistance to flow.

For that reason, since FY 2011 till FY 2019, JICA has continuously implemented basic research (general survey and analysis) about the improvement of road's resistance to flow and as a result, revealed cases of those damages and issues in each process of research, design, and construction.

Based on the results, JICA published "Road Pavement Handbook For JICA Grant Aid Project" (February 2020) that was about rutting countermeasures based on Japanese road design standard and also referring to standards of other countries.

What is road rutting?

Road rutting is groove-shaped deformation of the road surface caused by traffic load.

JICA-Net multimedia-based learning materials "Road Rutting Countermeasures in Tropical Regions" (external link) was produced based on the previously mentioned handbook. The material aims to widely introduce Japanese knowledge and experiences given by basic research into other countries and contribute to improve the quality of road pavement construction in tropical region.

Road rutting is groove-shaped deformation of the road surface caused by traffic load. It is a problem that appears sometimes as early as a few months after completion of the asphalt paving. Among asphalt pavement damage on roads in tropical countries, flow rutting is a common issue, which causes the asphalt mixture on the road to deform like soft candy.

Based on the experiments of JICA's projects, the material introduces researches to prevent road rutting, countermeasures and attentions in the process of design and operation, with actual examples shown by video.

When we produced this material, we were able to get many pictures and documents from domestic companies and organizations, and experts concerned with JICA. Because "road rutting countermeasures" was a highly specialized subject of the asphalt pavement, we intended that people understood it easily by inserting CG, illustrations, and flow chart into the material. So we recommend that people read the handbook with the material.

Aiming to improve the quality of road pavement construction

JICA will continue to contribute to high quality road development in various countries.

We suppose that this material will be utilized as a material for the program lectured by JICA experts who belong to JICA Financial Cooperation Implementation Department, and also as a material for JICA Knowledge Co-Creation Programs in the field of roads that is performed by JICA Infrastructure Management Department. Moreover, we expect that it will be used as the training material for domestic construction consultants and construction companies. The material will be helpful for negotiation and explanation of road design with the government when people research and prepare for grants aid in the field of road in developing countries.

Explaining Japanese knowledge of road and pavement design at the stage of negotiation will be effective not only for examination and smooth negotiation of the ongoing project but also for formation of a new project.

Through this material, we expect that Japanese knowledge and experiences will contribute to the high quality road improvement in many countries.

Taichi Suzuki
JICA Financial Cooperation Implementation Department

*The Material(s) mainly applied

Road Rutting Countermeasures in Tropical Regions

For sharing pavement technique and countermeasures in developing countries different from those in Japan with the consultants, the contractors and the engineers in developing countries, this material introduces how to deal with specific circumstances, such as flow rutting, the negative effect of water on pavement and explains special soil, based on the experience of JICA project.

This material has been compiled primarily with the objective of preventing reoccurrence of damage and improving quality of pavement works in light of the fact that, in road design works implemented within assistance preparatory surveys for grant aid projects, numerous cases of pavement damage were reported mostly in tropical countries around 2010.

• YouTube (external link)