An improved concrete is provided having a concrete formed from a wet concrete mixture; and a non-chemical admix added to the wet concrete mixture and configured to contain bubbles in order to control the amount of entrained air formed in the concrete when the wet concrete mixture cures into the improved concrete. The non-chemical admix includes a multiplicity of hollow objects, bodies, elements or structures, each configured with a respective cavity, unfilled space, or hole to trap and maintain a bubble inside. The hollow objects, bodies, elements or structures include hollow cylinders, or spheres, or capillary tubes, or some combination thereof. Each hollow object, body, element or structure is configured with a dimension so as not to absorb liquid, including water, including where the dimension is in a range of about 20-30 microns, and is made of glass or a glass-like material.