The suitability of aggregates from weathered Peterhead granites

Concrete has traditionally been made using sand and gravel filler. Concretes have been compared using two variably weathered granites from north east Scotland as aggregates. This study investigates the differences produced in concrete made from different grades of weathered aggregate. As the intensity of weathering increases, the bond between mineral grains weakens and therefore the durability of the aggregate is diminished. The intensity of weathering can be shown by the loss of certain oxides in the rock mass. Some of the major requirements for concretes are the impact and abrasion values of the aggregates used, and the shrinkage and compressive strength of the concrete pro-duced. It can be shown that these values are all dependent on the mineralogy, geochemistry and petrology of the aggregate. Reiche (1945) defined weathering as "the response o