Patent ID: 9470672
Filing Date: 2016-10-18
CPC Classification: G01N

Claim Text:
1. A three-stage testing method for measuring self-desiccation effect on a cement-based material, comprising: 1) using a negative pressure tester for a capillary according to a tensiometer principle to measure an initial negative pressure of the capillary and then calculating a decreasing rule of an internal relative humidity of the cement-based material in a first stage according to the equations (1) and (2), 2) using a dew-point thermometer in a second stage to test an internal dew-point temperature of the cement-based material from final set to being shaped after addition of water for 24 hours, and then calculating an internal relative humidity according to equation (3): 3) using a relative hygrometer to monitor a decrease in the internal relative humidity of the cement-based material in a third stage; wherein, the first stage occurs from the cement-based material being shaped after addition of water to final set, which is 0-6 hours since the cement-based material is shaped after addition of water; the second stage occurs from final set to 24 hours after water being added, which is 6-24 hours since the cement-based material is shaped after addition of water; and the third stage occurs after 24 hours after watering being added, which is after 24 hours since the cement-based material is shaped after addition of water.