Abstract:

Abstract: In case shotcreting is executed in extreme cold areas, the mixing, transportation and spraying of the shotcrete are performed under low temperature and low pressure, which results in large volume of rebound, heavy workload and difficulties in shotcrete quality guarantee. The rule of the influence of the liquid accelerator content and the surrounding temperature on the cement paste setting time is studied, the optimum accelerator content is established and the mixing ratio of the shotcrete is designed. The temperature control measures and shotcrete quality control measures taken in the job site are described. In the end, satisfactory results are achieved.

Key words: QinghaiTibet railway, liquid accelerator, shotcrete, mixing ratio