Modelling the pressure dependence and the influence of added polymeric fibers on the permeability of refractory concretes

摘要

In order-facilitate the water evacuation during drying, polymeric fibers are added-refractory concretes. A permeability model using Bruggeman's approach is developed-predict the permeability increase due-the fibers addition. This model (without adjustable parameters) knowing the fibers geometry (given by the manufacturer) and added amount (mass fraction varying between 0 and 0.20%) is validated by a thorough comparison with experimental results. The refractory permeability is measured at ambient temperature varying the quantity of added organic fibers after the samples were fired at different temperatures (from 80 °C-500 °C). The analysis of results is especially careful-take into account the influence on the permeability, on both pressure (Klinkenberg effect) and firing temperature. The agreement between theoretical and experimental results is shown-be very satisfactory.