Sustainable development of Portland cement: Effect of different types of accelerators on the setting time

Cement should be partially replaced by supplementary cementitious materials to reduce the environmental impact of itsproduction. Generally, this replacement increases the setting time of Portland cement, which leads to the formation ofcracks on the concrete surface, and consequently, a reduction in concrete durability. To overcome this issue, the effectof different types of accelerators on the initial and the final setting time of Portland cement was investigated. Resultsindicated that the ultimate behavior of calcium chloride and sodium silicate on the setting time were almost the same.These substances were very effective on the reduction of the final setting time of cement at low substitution dosage,while the initial setting was marginally reduced. Aluminum sulfate, in contrast, had a substantial impact on the initialsetting time at low dosages while all of the accelerators reduced initial and final setting time at high substitutiondosage.

Keywords:

Aluminum sulfate , Calcium chloride , Sodium silicate , Sustainable development , Setting time , Accelerator