method of preparation of concrete frost resistance

摘要

A process is provided for making frost resistant cement products having improved 28 day compressive strengths wherein a gas is included in the product by substantially uniformly dispersing hollow gas filled synthetic polymeric spheres in the cement mixture prior to setting thereof. The invention also provides a frost resistant cement product having from about 0.01 to about 0.1% by weight based on the weight of cement of synthetic polymer spheres filled with air and having a diameter of from about 10 to about 100 mu m substantially uniformly dispersed therein.