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Semen
STRUCTURE & PHYSICSbeginner
Definition
Portland cement — the fine grey powder that is the primary binder in all concrete, mortar, and plaster mixes used in Indonesian construction. Semen is purchased in 50 kg bags and mixed with pasir (sand), batu-split (coarse aggregate), and air to produce cor-beton (cast concrete). Quality grades range from ordinary Portland cement to white cement used in finishing applications.
Example
A standard Indonesian concrete mix for structural use is '1:2:3' — 1 bag semen, 2 parts pasir, 3 parts batu-split — the ratio taught in every construction school and used on every concrete site across the archipelago.