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Herein, the pre-heating treatments are researched. With diversity of zone and temperature, highest average temperature of the section 10cm below surface was 14.7°C, which is lower than that of the concrete block. And the distance of 20cm and 40cm to surface of section, the temperature is 11.8°C and 9.8°C， respectively. When the heating water of 60°C, the increase of 48h to 72h, the highest temperature is about 47.2°C and 49.6°C.

The influences of the rust layer on the passivation and corrosion of Q235b carbon steel in simulated concrete pore solution were studied. The differences between the inner and outer rust layer were characterized. Results show that the pre-rusted samples could still reach passive state at high pH condition free of chloride ions. However, the quality of the passive film formed on the pre-rusted steel were dramatically lower than that formed on the fine polished steel. The pitting corrosion resistance of the pre-rusted steel was significantly higher than that of the fine polished steel in the chloride-containing pore solution. The pitting corrosion potential would be further promoted after the elimination of the outer rust layer. The reaction between the hydrogen ions and the rust layer could inhibit the pitting initiation. Furthermore, the consumption of the corrosive agents induced by the rust layer could further retard the area expansion of the pits. [ABSTRACT FROM AUTHOR]

The 24 km ShenZhong Link is composed of bridges, vislands, tunnels and underwater communication. The bridge section involves a number of bridge pier, the bridge pier adopts the reinforced skeleton to be manufactured in the factory, and shipped to the site for hoisting and pouring the concrete. The concrete has a large amount of cementitious materials, adiabatic temperature rises, large volume of one-time pouring, and the environment is complex, the risk of concrete cracking is great. In order to solve the problem of the concrete cracking in ShenZhong Link, a typical bridge pier No.34 is taken as an example, and a multi-factor coupling finite element analysis method was taken as an object for study. A full-scale pier model test was carried out simultaneously, and optimization measures were targeted according to the test results. The bridge pier No.34 was observed several times after demolishing the mold, and no harmful cracks were found, and the crack control effect was significantly improved. [ABSTRACT FROM AUTHOR]