Compressibility of Japanese landfilled/buried waste samples: measurement of compaction curves and consolidation test for compacted waste samples at different compaction levels

Abstract

Compressibility characteristics of landfilling and buried waste samples are highly heterogeneous, depending on various waste compositions, degree of organic matters, decomposition, and so on. Measured data presented in this paper are the results from laboratory tests for different types of landfilling and buried waste such as incineration ash, industrial waste (plastics, rubbers, etc.) and un-burnable domestic waste (glasses, ceramics, etc.) and buried industrial solid waste fully mixed with soil from an industrial waste landfill at Saitama Prefecture in Japan, respectively. Prior to the compaction and consolidation tests, each sample was dried and the waste composition and particle size distribution were determined. Standard proctor compaction tests were carried out to discuss the compaction properties. For the buried industrial solid waste fully mixed with soil (two sample fractions: < 2 mm and < 9.5 mm) and incineration ash samples, optimized water contents (wopt) which gave the maximum dry bulk densities can be measured similar to typical soil samples. On the other hand, for the industrial and domestic waste samples mainly composed of plastics and glasses, the values of wopt could not be clearly observed and measured dry bulk densities were not controlled by the initial water content of samples. Consolidation tests for compacted samples at different compaction levels were carried out by using a specially designed oedometer in the laboratory. Based on the results from consolidation tests, the compressibility characteristics will be discussed based on the consolidation indices such as compression and consolidation coefficient, and their dependency of waste composition and fraction and surrounding environment (e.g., temperature).