Which of the following statements is/are correct in respect of Portland cement? Select the answer using the code given below :
II only
Statement I is not correct: a higher water-cement ratio actually delays (increases) the initial setting time rather than accelerating it. Statement II is correct: a small percentage of gypsum is added to Portland cement clinker to retard the otherwise rapid setting reaction of tricalcium aluminate, giving the desired working time. Statement III is not correct: gypsum retards, it does not accelerate, the setting time. Hence only statement II is correct.
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