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 significantly from 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, which is worldwide available and cheap material,
commonly used for packing) retrofitting technique has been developed and
many different aspects have been studied using brick and adobe masonry
structures by Meguro Laboratory, Institute of Industrial Science, 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.
