INFLUENCE OF SOME TECHNOLOGY PARAMETERS ON THE STRUCTURES OF AUTOCLAVED LIME-SAND CONCRETE

Autoclaving schedule, calcium-silicate (C/S) ratio and water-solid (W/ S) ratio are considered as the important technology parameters affecti ng the properties of autoclaved lime-sand concrete. Furthermore, the p roperties of autoclaved lime-sand concrete depend on its microstructur es, such as pore structures and calcium silicate hydrates. This paper examines the effect of the above-mentioned important parameters on por e structure, the contents of calcium silicate hydrates and Ca(OH)(2) i n autoclaved lime-sand concrete. The results show that W/S ratio affec ts both total pore volume and the volume of pores larger than 500 Angs trom radius of autoclaved lime-sand concrete. When an autoclaving sche dule is stronger than a critical autoclaving schedule at a given mix, it exhibits less effect on pore structure, the contents of Ca(OH)(2) a nd calcium silicate hydrates. An insufficient autoclaving schedule, sp ecially 'peak autoclaving schedule', causes coarseness of pore structu re, more Ca(OH)(2) and lower content of calcium silicate hydrates. The structure-property relationships are discussed.