In order to have a good knowledge of applicability of time-domain reflectometry（ TDR） technique to test water content of standard sand

calibration experiment for small indoor sand-box model that use TDR sensor to test is designed

influence mechanism of water content and dry density on stability and accuracy of TDR transducer is analyzed. The tests show that when testing the sand that the water content is 5 %

15 % and dry density changes at range of 1. 40

1. 60 g / cm3

the determination results reflect that the TDR sensor has an excellent stability at the 0. 05 significance level; the determination results of medium dense sand which the water content is2. 5 %

17. 5 % and loose-dense sand with 10 % show the accuracy of TDR sensor comfort the code requirements; the effect of density on TDR technique is a positive correlation

thus a density correction coefficient for the TDR when measuring the water content is proposed.