In 1989, a manual was prepared for the use of granulated slag for harbor construction. Since then, granulated slag has been widely used. Some of them have been constructed for nearly 10 years, and we are now in a situation where we can grasp the long-term characteristics of granulated slag. In particular, there were many unclear points about the caking of granulated slag, but as a result of the ground investigation this time, the following conclusions were obtained regarding the secular change of granulated slag.
1) Granulated slag below the groundwater table tends to solidify in the long term.
2) Physical properties and mechanical properties of granulated slag in situ have relatively large variations.
3) The range of solidification strength of water granulated slag is about 0.87 to 18kgf/cm2. The internal friction angle obtained from the residual strength is over 37°.
4) The hydraulic conductivity of solidified granulated slag is on the order of 10-3 cm/sec, and does not change significantly even after a long period of time.
5) The ph of the solidified granulated slag was about 11 according to the Japanese Geotechnical Society standard, but the ph of the water passing through the gap was slightly smaller, about 9-10.