Development of a Flat-type TDR System for Compaction Control

다짐관리를 위한 판형 TDR 시스템 개발

Song, Minwoo;Choi, Chanyong;Kim, Daehyeon

  • Received : 2016.03.14
  • Accepted : 2016.03.28
  • Published : 2016.04.29


In this study, a new TDR system equipped with a flat type probe has been developed to improve the currently used TDR system that measures dry density and water content. To verify the developed TDR system, TDR tests were conducted on Jumunjin sand and three typical soils. Also, additional tests were performed to measure the correction value of the developed probe. Using the TDR signals, dielectric constant, electrical conductivity and soil constants were derived. The water content and dry density of the soils were determined through the TDR tests. The applicability of the TDR system was examined by comparison of the measured values by TDR and the real values. The values of dry density and water content were found to have about 2% and 0.5% error, respectively. Based on the test results, it has been confirmed that the new TDR system can be used as an alternative to the previous TDR system as it can measure the dry density and the water content with reasonable accuracy, leading to significant time and cost savings.


TDR;Nondestructive system;water content;dry density


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