construction materials Flashcards
what material is used in buildings?
stone such as limestone, marble and granite
what are stone buildings usually made from?
limestone
why is limestone better
easier to cut into blocks than marble or granite
explain marble
hard
explain granite
harder still and very difficult to shape
what is stone used for?
an attractive front
what are large structures made form?
a steel frame or reinforced concrete
what can walls be made from?
brick, concrete aluminium or glass
what are the 5 raw materials, and what can they be to make?
clay-brick, limestone and clay-cement, -sand-glass, iron ore-iron, aluminium ore-aluminium
what are the 3 types of rocks?
igenous, sedimentary, metamorphic
give an example of igneous rock and explain its hardness
granite is very hard
give an example of metemorphic rock
marble is not as hard as granite
give an example of sedimentary rock
limestone if the softest
how is igneous rock formed?
out of liquid rock that cools and forms interlocking crystals as it solidifies
what is metamorphic rock?
rock that has been changed
why is metamorphic rock harder?
because it has been subjected to heat and pressure in the earths crust, which makes it harder
what is sedimentary rock made of?
fragments that have settled into layers
how was limestone formed?
form shells of dead sea creatures that have stuck together
what are marble and limestone forms of?
calcium carbonate
what happens when calcium carbonate is heated?
it thermally decomposers to form calcium carbonate and carbon dioxide
how do you make concrete?
mix cement, sand, aggregate with water and allow it to set
what is bad about quarries?
dust pollution, damaged landscape, noise, lorries
what can they be used as afterwards?
filled in with grass, used as rubbish tip then cover with soil, as a lake or pond for fishing or sailing
what is the equation for calcium carbonate decomposing?
calcium carbonate — calcium oxide + carbon dioxide
what is thermal decomposition?
the chemical breakdown of a compound into at least two other compounds in the effect of heat
how is cement made?
limestone is heated with clay
how is mortar made?
cement mixed with sand and water
what is mortar used for?
sticking bricks together but its not strong enough to use on its own
what is reinforced concrete?
concrete that has steel rods going through it to make it stronger
what happens if you put heavy weights on concrete?
it bends slightly
what is good about steel?
its flexible and is strong under tension
why do cracks start to form in concrete when there is tension?
when a beam bends its underside starts to stretch
