Stabilization of clay with inorganic by-products

New binder alternatives based on industrial by-products were studied for st abilization of clayey soils. The main emphasis was on pulverized, granulate d blast-furnace slag activated in different ways, and on binder combination s based on fly ash and waste from desulfuration units. Cement was used as t he control binder. The aim of this study was to evaluate the stabilization characteristics of new binder alternatives with different mixture combinati ons and to understand the effects of geotechnical index properties of clay and chemical/ mineralogical composition on stabilization characteristics. T he results of the laboratory tests indicate that the strength of stabilized clay is strongly dependent on the water-binder ratio, and that the strengt hening effect is minimal at water-binder ratios below a certain threshold v alue. For the clay types examined in this study blastfurnace slag activated with cement generally gives higher strengths than cement alone after the r elatively long hardening periods usually employed in stabilization. It is p ossible to predict final strengths by accelerating the hardening with heat treatment. A temperature of 60 degreesC seems to be suitable for this accel eration.