COLLAPSE BEHAVIOR OF COAL ASH.

Abstract

Abstract: The paper describes an investigation carried out to examine the factors influencing collapse settlement of the compacted coal ash due to wetting. The ashes produced by the coal fired thermal power plants are stored as a high mound in the disposal dump. Some of the ash dumps and ash fill structures wetted under certain conditions of loading may exhibit collapse. Attempts have been made to correlate the ash characteristics and the specific placement parameters such as ash type, soluble content, degree of compaction, overconsolidation ratio, moisture content, and stress level at wetting with collapse. This was based largely on the oedometer and partly on the model and the field test results. 378 single oedometer tests were conducted to obtain the collapse potential. The collapse potential was correlated with the mean size of the ash. The favorable pressure, moisture, fines, compaction, soluble substance, and prestressing decrease the collapse potential of an ash fill. The collap...