Field test on applicability of copper slag sand to sand compaction pile method

More than 1.8 million tons of copper slag sand, a by-product obtained from refining process of copper, was produced annually in Japan. Since the slag has relatively large specific gravity of soil particle, large internal friction angle and high permeability, it is expected to be used as a construction material especially for the sand drain method and sand compaction pile method. The sand compaction pile method has been extensively used in Japan in which compacted sand piles are constructed in a soft ground to improve its stability and/or compressibility. Recently limited amount of sand suitable for the method requires research efforts to find new material for the method. Authors started a research project on applicability of the copper slag sand to the SCP method in which laboratory, centrifuge and field tests were performed. In this paper, field construction test was described in detail as well as the properties of the slag.