This process actually has a name called Ice wedging , where water seeps through small cracks and then when it drops to a freezing temperature. Ice is created and the crack expands.
Carbohydrates contain only carbon, hydrogen and oxygen atoms; prior to any oxidation or reduction, most have the empirical formula Cm(H2O)n. Compounds obtained from carbohydrates by substitution, etc., are known as carbohydrate derivatives and may contain other elements.