Construction Materials

A Year Ten module from the Salters’ double award science course. A surveyor’s report on a proposed barn conversion is used to introduce different materials used in construction and issues associated with their use. The lessons which follow then consider each type of material in turn, reviewing structure, properties and uses. Different types of stone are examined, and compared to brick. The effect of acids on stones leads to the reaction of carbonates with acid and an introduction to reaction rates. The properties of fired and unfired clay are compared, and the effect of frost on bricks may be tested. A home survey reveals the extensive uses of plastics in construction and the idea of polymers is introduced (it is developed more fully in the module Making use of Oil). Paper-chain models of polymers are used to show the effect of cross-linking.

Study of rusting wall ties introduces corrosion of metals and simple experiments revise knowledge of rusting. A paper exercise covers the blast furnace and displacement reactions revise ideas about the reactivity series from Key Stage Three. Finally, students apply knowledge gained from the module to select the best materials to use in the barn conversion.

Section1: What can a survey tell us?
A text activity based on a surveyor’s report for a proposed barn conversion introduces natural and manufactured materials used in construction, their properties and characteristics.

Section 2: Making and testing construction materials
Students make and test model bricks, comparing the properties of fired and unfired clay and relating these to molecular structure. Paper-chain models of plastics reveal the effect of cross-linking on bulk properties.

Section 3: Winning and losing Iron
A text exercise describes the blast furnace process for extraction of iron. Experiments on rusting revise ideas about corrosion. A study of corrosion of iron in contact with other metals revises and extends ideas about the reactivity series. Further tests on displacement reactions lead to discussion of the relationship between confidence in theoretical explanations and the quality of the supporting evidence.

Section 4: Comparing different types of stone
Experiments to illustrate the properties of different types of stone. The action of acid on limestone introduces ideas about factors which affect the rate of chemical reaction.