The Durability of RPC with Different Content of Silicon Powder

The volume stability, freezing-thawing cycles, the resistance of chloride ions and sulfate attack of RPC with different content (0%, 40%, 100%) of silicon powder are investigated in this paper. The results demonstrate that the volume stability and the resistance of freezing-thawing for RPC with 40% silicon powder are improved because of a high compactness, whose shrinkage is only 350 x 10(-6) for 60 d and tends to this value after 60 d, and the relative dynamic modulus is more than 99% after 300 times of freezing-thawing cycles. Meanwhile, with a high content of active SiO2 and a low magnesium content, the resistance of chloride ions and sulfate attack of RPC with 40% silicon powder are improved attributing to a high compact structure and a low level of magnesium sulfate attack. This leads an increase of the com(p)ressive strength with 5.6% after 150 times of wetting-drying cycles in the solution with 5% (NaSO4)-S-2.