Abstract: Portland pozzolanic cement delivered to a construction site was having quick setting time and could not harden after 24 hours. Due to this problem a study on some physical and chemical properties of cement was done to determine the various components of cement. East African Standard procedures were used to determine properties. The results showed that only SO3 and chloride were okay. The initial setting of five minutes was very quick and low when compared to the standard of around 75 minutes. Very high values of SiO2 and insoluble residues, high values of Al2O3, Fe2O3, MgO and loss of ignition were observed and did not meet the standards. In addition, low compressive strength of 26.54 N/mm2 was observed. Lime saturation factor and chemical modulus of 0.46 and 1.46, respectively were low compared to the standard. The quick setting time could be attributed to low CaO of 45.16%, and high values of Al2O3 and Fe2O3. The lack of hardening and compressive strength could be attributed to high values of Insoluble residues. Cement users are therefore requested to test their cement before using.

Keywords: Setting, pozzolanic, insoluble residues, East African Standards, compressive strength.

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