Composition of Good Brick Earth and its Properties thats effect on bricks
composition | in percent | properties contribution | property on excess |
---|---|---|---|
Silica | 50-60% | retaining the shape of brick prevent cracking, shrinkage,warping of raw brick | destroy the cohession between particlesand make brick brittle |
Alumina | 20-30% | plasticity to brick | weak and warp ondrying of brick |
Lime | 10% | prevent shrinkage on drying | melt and brick loose its shape |
Iron Oxide | <7% | gives red colorhelps lime to fuse with sand | dark blue color |
manganese oxide | <1% | yellow tint colordecrease shrinkage | decay of brick |
sulphur oxide carbon dioxide | very small | spongy, swollen structure in the brickdecolored by white blotches | |
water | very small | ||
Note | good clay for making the brick is weathered clay. | ||
Alkalies | very small | melt and loosetheir shape | |
Organic matter | none | after burning leaving pores and make brickporous | |
Pebbles, Gravels, Grits | lesser | weak and porousnot give uniformity during mixture |