The applied effects and thire mechanisms of four kinds of grinding aids are studied here. The results show that different grinding aids have different effect on fineness, flow property, particle size composition and distribution, especially the particle size of 3～30μm and mortar strength of 3 and 28 days. The effect of grinding aids can be expressed by fineness, particle size composition and distribution, flow property and cement mortar strength. And it might not be sutible for expressing the grinding aids with Blaine specific surface and 80μm sieve. The function mechanism of grinding aids is to reduce comminution resistance , prevent agglomeration and mill coating, as well as flow property,so as so intensify the frequency and efficiency between particles and media.

Horomill is one of the advanced cement grinding equipments in cement industry it incorporates energy savings of roll press, reliability of ball mill. In this papen, the service principle, theory formulary design of Horomill are analyzed and deduced. The new stress analysis model of the Horomill was established. Based on the partitioning, two different sections of fragmentation and compaction, the stress state and theory formulary of main parameters for Horomill design were deduced. Combined with the industrial test results, formulary of main parameters for Horomill design was given.

In order to improve crack resistance of concrete, test and analysis are made on the influence of mineral compositions of cement on brittleness of sand grout. Brittleness of sand grout can be decreased by adding mineral compositions, and cracking resistance of concrete is thus improved.