Papers by Author: Lin Yang

Abstract: In this paper, non-fired load-bearing wall bricks were prepared with high volume of white mud and CFBC fuel ash in laboratory scale. The effect of manufacturing parameters on the performances of the brick, such as mechanical properties, antifreeze and dry shrinkage, etc., were investigated. The impact of different curing regimes on these performances of the bricks with various raw materials formula has also been investigated. The experimental results show that the compressive strength of the brick could come up to 25.1MPa and the all other performances can meet Chinese national standard requirements. The best formula that bricks having the best performance is when the white mud dosage is 30%, and the best curing regime is autoclaved 180°C, 10h. The microstructure of the brick was examined by FESEM, XRD and EDS. Tobermorite (C₅S₆H₅) has been generated at this time, which has a better crystallinity and has a higher silicon polymerization degree.

Abstract: Non-fired load-bearing wall brick was prepared utilizing non-treated original waste PG as raw material in the laboratory. When the amount of PG and cement is 65% and 10% (by weight) in the brick mixture, respectively, the compressive strength of bricks is still over 23MPa and the flexural strength comes up to 4MPa. Besides, the bricks hold excellent water-resistance and frost-resistance. Effects of steel slag or/and fly ash content on performance of bricks and effects of the change of sand content on water-resistance and frost-resistance are discussed. Results indicate that the compressive strength, flexural strength and soft coefficient are higher when blended mineral additive with various amounts of steel slag and fly ash. The frost-resistance goes up with the increase of the steel slag content, the water-resistance and frost-resistance goes down when the sand content decreases from 15% to 10%, no matter the 5% sand was replaced by fly ash or steel slag as equal weight. Microstructure of brick was investigated by XRD and SEM. Strength of brick results from a large amount of AFt (3CaO•Al2O3•3 CaSO4•32H2O) and C-S-H (calcium silicate hydrate) presented in the matrix which may be viewed as the biggest strength contributors bonding the gypsum and quartz together to a compact matrix.