STUDY ON DIELECTRIC PROPERTIES OF HARDENING CEMENT PASTE

摘要

The dielectric properties and mechanical properties of hardened cement paste samples withdifferent w/c ratio were investigated by HP4294A impedance analyzer and compressivestrength test, respectively. The microstructure of the cement paste samples were analyzed byscanning electron microscope (SEM). The results showed that the capacitance stronglydecreased with the increase of applied frequency when frequency was lower than about 200kHz, but it changed little when the frequency was higher than 200 kHz. The capacitance ofthe paste cured for 28 days was higher than that of the paste cured for 14 days. With theincrease of w/c ratio, the compressive strength decreased while the capacitance increased forthe hardened cement paste cured for 28 days. This research indicated that there is arelationship between the strength and the electric properties. With the increase of curing age,the relationship between the strength and the capacitance was much better when themicrostructure of the samples became denser.