Affiliation:
1. Dept. of Civil Engineering, Qazvin Branch , Islamic Azad University , Qazvin , Iran
2. Dept. of Civil and Environmental Engineering , University of Hawaii at Manoa , Honolulu , USA
Abstract
Abstract
The interval of time after pouring concrete is an important factor, which directly affects the timing and cost of construction. The case study that was investigated in this research, is a tunnel project located in Iran. Eighteen mix designs were prepared using properties such as different water-cement ratios and the use of two types of superplasticizer with different dosages. The optimal mix designs among the samples were separately specified.
Concrete mix designs with different curing ages were made to specify the minimum curing time in which the concrete could gain the required compressive strength. Moreover, the concrete’s compressive strength was measured for different ages in order to determine the minimum time interval. For a better insight, two mathematical equations were derived to estimate the minimum curing time and time interval. Finally, a statistical analysis was conducted in order to determine the proper time intervals. Moreover, the analysis specified the impact rate of the research parameters (i.e. the type and dosage of superplasticizer, curing time, and water-cement ratio) on the compressive strength
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