The purpose of this study is to understand the effect of drying and wetting (DW) cycle on the unconfined compression (UC) properties of the solidified geomaterials mixed with wood chips, which imitates the under-sieve residue, steelmaking slag and blast furnace slag fine powder. The experiment was carried out by changing the shape of wood chips (fibrous / granular) and the number of DW cycles (0, 2, 4 or 8 times). The following observations were made: (a) The effect of DW on UC properties differed depending on the shape of the wood chips. (b) When granular wood chips were mixed, there was almost no change in the volume of the specimen due to DW. However, when fibrous wood chips were mixed, the volume of the specimen expanded significantly due to DW. (c) When fibrous wood chips are mixed, the volume of the specimen would not expand unless either drying or wetting occurred. From these results, it is considered that the slag containing a large amount of granular wood chips can be sufficiently used at the surface layer where DW cycles are likely to happen. On the other hand, the slag containing a large amount of fibrous wood chips should be used in the ground that always contains water, not at the surface layer.
