功能材料替代碳纤维对水泥净浆电阻率的影响

Effect of replacing carbon fiber by functional materials on the electrical resistivity of cement paste

研究了碳纤维掺量、长度对水泥净浆电阻率的影响,并探讨了功能材料替代碳纤维水泥净浆电阻率的变化。试验结果表明:随着纤维掺量的增加,水泥净浆的电阻率下降,并存在导电渗流现象,渗流阈值在1.0%左右;碳纤维掺量一定时,在3-9mm范围内水泥净浆的电阻率随着纤维长度的增加而降低;功能材料(石墨、炭黑)分别替代10%、25%、40%、50%和60%时,电阻率呈现先减小再增大,再减小再增大的趋势;石墨最优替代比例在40%左右,石墨和炭黑在25%到40%之间,炭黑在40%左右。

Effect of carbon fiber on the electrical resistivity of cement paste was investigated.Replacing carbon fiber by functional materials in cement paste, the changing of the electrical resistivity was also studied.The results showed that resistivity of cement paste decreased with the increasing of carbon fiber＇s content, and there was a conductive percolation phenomena, the percolation threshold was about 1.0%. At a fixed content of carbon fiber,the electrical resistivity of cement paste decreased with the increasing of carbon fiber＇s length,when the length increased to 9 mm fi＇om 3 mm.Replacing carbon fiber by functional materials in cement paste ,replacing ratio was 10%,25% ,40% 50% and 60%.The electrical resistivity of cement paste decreased first, then increased, then decreased, increased again.When graphite and carbon black solely replaced carbon fiber respectively, the optimal value of replacing ratio was about 40%.When graphite and carbon black replaced carbon fiber together, the optimal value was between 25% and 40%.