Alkali activated cements mix design for concretes application in high corrosive conditions

Abstract

This paper covers the results of development of corrosion resistant ash alkali-activated cements based on regulation of phase composition of the hydration products through changing the alkali content, content of calciumcontaining cement constituents resulting in the increase strength and density of the cement stone. The results of study suggested to conclude that the cement compositions with predominance in the hydration products of weakly soluble low basic hydrosilicates of calcium, hydrogarnets and minerals similar to natural hydroaluminates exhibited the highest corrosion resistance. The results of comparison suggested to draw a conclusion that the alkali-activated cements Types APC III-400 and ACC V-400, according to National Ukrainian Standard DSTU B V.2.7, had high corrosion resistance compared to that of OPC, thus allowing to recommend the developed cements for the concretes intended for use in aggressive environments, inclusive of sodium and magnesium sulphates and others. Coefficients of corrosion resistance of concretes are higher than 1 after even 42 months.

Design of slag cement, activated by Na (K) salts of strong acids, for concrete reinforced with steel fittings

“…The alkaline activation of aluminosilicate raw materials is widely used in the production of modern building materials [11]. Concrete based on the alkaline-activated types of cement is characterized by the increased indicators of strength [12], heat resistance [13], corrosion resistance [14], sulfate resistance [15], frost resistance [16], water resistance [17], compared to analogs based on conventional clinker concrete. Along with the high performance properties, the alkaline-activated slag cement can be used as a base of decorative materials [18].…”

Development of technology of utilization of products of ferritization processing of galvanic waste in the composition of alkaline cements

“…Given this, there is a need to develop reliable methods for processing galvanic waste. Known methods of neutralization of hydroxide sludge are associated with their use as additives in the production of various materials: concrete [5], expanded clay [6], asphalt [7], Portland cement [8], bricks and ceramics [9]. It is also possible to produce pigments and catalysts from them [10].…”

Development of a technology for utilizing the electroplating wastes by applying a ferritization method to the alkaline­activated materials

“…Previous studies have shown that alkaline cements are resistant to the effect of aggressive environment [11], they excellently interact with solutions of sulphates and chlorides [12], and possess a wide range of unique operational properties [13]. They make it possible to reliably fix in their structure the elements of radioactive and HM, not only at the physical [14] but also at the chemical level [15].…”