Application of Weathering Process Phenomena Modify Decomposed shale to be Used as Core-Zone Material in an Earth Filled Dam

Abstract

Most of the reservoirs in Thailand, in the form of earth filled dam construction, have been constructed by using soil materials which investigating in the reservoir and the adjacent area. In some projects, the result of investigated volume of soil showed the insufficiency of soil. By this event, The Klong Tron irrigation reservoir project in Uttaradit Province, north of Thailand, has faced to it. During the investigation we found most of moderately to highly decomposed shale appearing at the toe of mild mountainside in the reservoir rim. After we dig it up and curing to the period of 24 days, it was alterated to clayey soil and given their basic engineering properties such as liquid limit and plasticity index equal to 40-56% and 18-29 respectively; maximum dry density 1.89-2.01 ton/cu.m corresponding to optimum moisture content 17-22% and coefficient of permeability 10^-5 to 10^-7 cm/sec.