Effect of Y type polypropylene fiber on plastic shrinkage cracking of cement mortar

The effect of Y type polypropylene fiber on plastic shrinkage cracking of cement mortar was studied. The test results showed that crack width and the total weighted cracking value decreased when Y type polypropylene fiber was added to the cement mortar. The effect of the fiber on plastic shrinkage cracking resistance increased with an increase in fiber volume fraction in the range of 0.05% to 0.15%. The total weighted cracking value decreased by about 88% at a fiber volume fraction of 0.15%. It was also found that, under these experimental conditions, the total weighted cracking value conformed to a trivariable linear regression equation with fiber volume fraction, temperature and relative humidity as variables. The relative importance of these three variables on plastic shrinkage cracking was fiber content>temperature>relative humidity.