Modification of pore chemicals in evaluation of high-performance concrete permeability

The pore chemicals and pore fluid conductivity of concrete vary greatly If the measured conductivity of concrete is used to evaluate the permeability of concrete, it should be modified with the pore fluid conductivity of conc rete. Because it is difficult to obtain the pore fluid from high-performanc e concrete (NPC) by the conventional method of expression of concrete, this paper puts forward a new method for the modification of pore chemicals in the evaluation of HPC permeability. When a mineral admixture like silica fume, slag,fly ash or zeolite is used to replace sone of the cement, or NaNO2 is used as a chemical admixture in concrete, and the modified resistance of concrete is used to reflect its pe rmeability, the permeability of most concrete decreases. But if the influen ce of pore chemicals is nor considered the benefit of mineral admixtures on reducing concrete permeability will be over-evaluated and that of NaNO2, w ill be underevaluated.