Abstract: Cementitious compositions in which the cementitious properties of fly ash are carefully controlled are described. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a lactic acid salt based activator is be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.

Abstract: Cementitious compositions in which the cementitious properties of fly-ash are carefully controlled. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a citric salt, for example potassium citrate, may be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.

Abstract: Cementitious compositions in which the cementitious properties of fly-ash are carefully controlled. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a citric salt, for example potassium citrate, may be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.

Abstract: Cementitious compositions in which the cementitious properties of fly-ash are carefully controlled. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a citric salt, for example potassium citrate, may be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.

Abstract: Composite materials made from reactive compounds such as oxides are disclosed. The materials comprise a reaction producing of metal oxide, phosphate and reactive residual materials. The metal oxide may comprise MgO, CaO, ZnO, TiO2 or the like. The phosphate may comprise mono-potassium phosphate, mono-ammonium phosphate, mono-sodium phosphate or the like. The reactive residual material may be ash, phosphate clay, phosphate residual slurry, mining waste or the like. The composite materials may be used for many applications including rapid repair materials, pre-cast structures, in-situ structures, mixes and coatings.

Abstract: Cementitious compositions in which the cementitious properties of fly-ash are carefully controlled. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a citric salt, for example potassium citrate, may be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.