As products and processes become more and more complex, there is an increasing need in the industry to perform experiments with a large number of factors and a large number of levels for each factor. For such experiments, application of traditional designs such as factorial designs or orthogonal arrays is impractical because of the large number of runs required. As an alternative, a type of design, called the uniform design, can be used to solve such problems. The uniform design has been intensively studied by theoreticians for several decades and has many successful examples of application in industry. In this article, we report a successful application of uniform design in product formation in the cement manufacturing industry. Specifically, we investigate the effects of additives on bleeding and compressive strength of a cement mixture. This example illustrates how an experiment of 16 runs was performed to study three factors with 16 levels, 8 levels, and 8 levels, respectively.

Previous research indicated epoxy resin based repairing materials have been widely used due to its outstanding advantages in strength, durability corrosion, abrasion resistance and reasonable price, etc. But its nonperforming resistance of ultraviolet radiation restricted popularization and using. In this paper the effect of inorganic fillers (quartz sand, rutile type titanium dioxide and talc powder) and organic fillers (HALS-770 and UV-P) on the Compressive strength of RME irradiated was studied. The results indicated that inorganic and organic fillers revealed good shielding effect. The inorganic fillers decreased the compressive strength of RME about 20MPa, and talc powder was better than quartz sand and rutile type titanium dioxide. Organic fillers had unaffected in strength, and combined use of HALS-770 and UV-P had better resistance than alone. The strength retention of RME with talc powder and combined with HALS-770 and UV-P irradiated 4500h were 85.65% and 93.5%.

The cement-based composite absorbing materials was made of portland cement and nano-titanic oxide absorbent. The relationship of electromagnetic wave reflectivity and nanometer TiO2 contents, dispersed means, samples thickness, and effect of nanometer titanium oxide on mechanical properties of cement-based composites were discussed in details. The experiment results revealed: 1) The reflectivity of cement-based composites with nanometer titanium oxide is less than -7 dB at 8~18 GHz frequency range; 2) The least reflectivity is -16.34 dB at 16.24 GHz and the bandwidth for -10 dB is 4.5 GHz; 3) The mechanical properties of cement-based composites with nanometer titanium oxide are superior to that of cement paste.

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Previous research indicated that the expansion property of MgO-type expansive agent (MEA) strongly depended on the amount. However, the quantitative effect of amount on expansion property of MEA has not been clearly demonstrated. In the present the expansion value of cement paste with 3%, 4%, 5% and 6% MEA calcinated at 850°C and 1200 °C, and then relative expansion value was introduced to investigated the relationship between the mount and expansion of MEA. The results indicated The relative expansion of MEA calcinated at 850°C was relative invariant to curing temperature and proportional increased with the amount ratio. The relative expansion of MEA calcinated at 1200°C proportional increased with curing age, and the increasing rate rose with the amount ratio of MEA and curing temperature.