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Q&A How can you build cities without cement?

Modern cities are built from concrete with steel rebar because it is abundantly available and provides enough tensile strength. Concrete requires cement. Cement is made from limestone. Limestone is...

19 answers  ·  posted 8y ago by Lorry Laurence mcLarry‭  ·  last activity 7y ago by Lorry Laurence mcLarry‭

Question cities technology engineering