Abstract
This research aims to clarify the mechanical characteristics of waste ground including plastics and propose methods to assess these characteristics. Mechanical characteristics of waste grounds including plastics have not been studied in sufficiently in Japan, because such grounds have been considered to be very elastic and difficult to use as land. However, in the previous research, it has been reported that waste grounds including plastics have high slope stabilities. The authors investigate characteristics of the waste ground including plastics such as slope stability, bearing capacity, subsidence, etc. Sizes of individual solid waste pieces in landfill ground including plastic are fairly large compared with that of the soil particles. It would require a huge and expensive test facility to accurately reproduce such actual sites indoors. Accordingly, the tests were conducted primarily on site such as plate loading test, box shear test in 19 sites (29 places) of landfills inside and outside of Japan. For simplified on site-test, impact bearing test, repose angle test and void test are proposed. The results of plate loading test indicate that the solid waste ground of the landfills with plastics has sufficient strength to permit construction of a heavyweight structure (for example, wind power generation). And bearing capacity could be estimated from the proposed impact bearing test and repose angle test. In addition, differential settlement is found to be unlikely to occur by the demonstration experiment on a landfill in central Japan. It is believed to be due to the transfer in the horizontal direction of the vertical force due to connection of the fibers. By proposed strength evaluation, it is expected that the waste ground is used as land.
