Abstract:
Unreinforced masonry structure is one of the most popularly used constructions in the world, especially in
developing countries. It is also unfortunately, the most vulnerable to the earthquake and its damage has caused many
human casualties. Therefore, from global viewpoint, retrofitting of low earthquake-resistant masonry structures is
essential to reduce the casualties by earthquake disaster. In developing countries, retrofitting method should be technically
feasible and economically affordable, the retrofitting material, accessible, and the workmanship, locally available.
Considering these points, PP-band (polypropylene bands, worldwide available and cheap material, commonly used for
packing) retrofitting technique has been developed by Meguro Laboratory, The University of Tokyo. In this research, we
conducted a series of experiments to verify the suitability of PP-band retrofitting for masonry structures made of shapeless
stones. Material tests were conducted to understand the basic parameters of stone masonry, i.e. shear, tension and
compression strength. After the material tests, diagonal compression test and out-of-plane test were carried out using
masonry wallette made of shapeless stones with and without retrofitting. From both test results, it was clear that PP-band
retrofitting improved drastically the overall stability and ductility of stone masonry structures made of shapeless stones.
