EFFECT OF ULTRAFINE MINERAL POWDER ON CHLORIDE DIFFUSION OF CONCRETE

摘要

The multi-functional composite ultrafine powder (abbreviated as Powder A), developed through the co-operation of the Weifang Traffic Engineering Supervision Center and Tsinghua University, could cure concrete of the "durability hazard syndrome" effectively. Properties such as the influence of Powder A and other ultrafine mineral powders on charge passed of concrete, the compatibility of air-induced agent, water-repulsive agent and colyseptic agent with Powder A, as well as the influence of Powder A dosage on the charge passed data of different W/B ratio concrete were investigated. It is shown that for concrete with W/B ratio less than 0.55, the replacement of cement with 30% of Powder A could decrease the 56 day charge passed data to less than 1000 coulombs, ranking it among the highly anti-permeable or highly durable concrete, while the Powder A is in good compatible with air induced a-gent(AI), water repulsive agent(WR) and colyseptic agent(CA).