According to at least one embodiment of the present description, a cement slurry includes 50% to 90% BWOC of a cement precursor material based on a total weight of the cement slurry; and from 10% to 50% BWOC of a flexible additive based on the total weight of the cement slurry. The flexible additive includes hydrophilic polyolefin fibers or 2,6-di-tert-butyl-p-cresol.