This paper presents the influence of ultra-fine fly ash on the strength development and durability characteristics of high performance road concrete. The durability of high performance road concrete is investigated including the permeation resistance under hydraulic pressure, the resistance to rapid freezing and thawing, the wear resistant ability and drying shrinkage. Results on compressive strength and strength development of high performance road concrete are also obtained with the main variables being the partial replacements of cement by ultra-fine fly ash of 20%, 30% and 40% by weight of binder material and the binder material of 360kg/m3 and 400 kg/m3. The test results indicate that the use of ultra-fine fly ash as cement replacement leads to a significant improvement of high performance road concrete resistance to permeation and rapid freezing and thawing. The later compressive strength of concrete containing ultra-fine fly ash is also found to be significantly higher than that of control concrete. The wear resistant ability of high performance road concrete is significantly higher than that of control concrete with similar workability. The high performance road concrete also shows the lower drying shrinkage.

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This paper describes the influence of raw material, water-cement ratio, sand ratio, cement-sand ratio and fly ash content on impermeability of waterproof concrete. The value ranges of several important mix parameters are summarized, that provides the reference to select the parameters of mix proportion of waterproof concrete for subway.

The bamboo processing residues, as raw material, was modified by quaternary ammonium to obtain a quaternary ammonium modified bamboo powder adsorbent. The phosphate’s adsorption capacity of the powder adsorbent was investigated. In addition, the effects of dosage, pH, time, temperature, initial concentration on phosphate’s adsorption capacity. Then, the research performed the adsorption isotherm model fitting. The results showed that the adsorption rate of modified bamboo powder to phosphate increased with increase of dosing amount of modified bamboo powder, tended to be equilibrium when the removal rate reached to 97%; while the phosphate with high initial concentration could improve the adsorption capacity of modified bamboo powder. In acidic condition, the modified bamboo powder presented unsatisfied adsorption effect on phosphate, when pH= 6 the adsorption effect become well, but adsorption effect did not vary apparently with the increase of pH. With the increase of temperature (25, 35, 45°C), the maximum saturated adsorption capacity of modified bamboo powder gradually reduced. The adsorption of modified bamboo powder on phosphate was a rapid process, which could reach equilibrium status within 50 minutes. The bamboo powder before and after the modification was conducted IR element analysis, the values before modification are N=0, C=45.54 and H=6.03; while after the modification, the values are N=2.65, C=40.33 and H=6.79, it is concluded that the nitrogen content of modified bamboo powder increase obviously and the quaternary ammonium can well be grafted.

The development of water based capillary inorganic water proofer is discussed in this paper. By practical engineering application research, the influences of water based capillary inorganic water proofer on concrete strength, impermeability, carbonation resistance, wear resistance and corrosion resistance are summarized. Finally, the prospect of application of water based Capillary inorganic water proofer is pointed out.