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Research Article

Analysis of Sand Water Ratio and Drying Unit Weight Using Flat TDR System

Flat TDR 시스템을 이용한 모래의 함수비와 건조단위중량 분석

Junesung Lee1
Daehyeon Kim2*
이 준성1
김 대현2*
1Graduated Student, Department of Civil Engineering, Chosun University
2Professor, Department of Civil Engineering, Chosun University
1조선대학교 토목공학과 박사과정
2조선대학교 토목공학과 교수
*Corresponding Author
30 September 2021. pp. 333-342
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Abstract

본 연구에서는 기존의 전통적인 다짐관리방법의 문제점을 보완하고자 TDR(Time Domain Reflectometry)을 이용하여 지반의 함수비와 건조단위중량을 측정하는 연구를 수행하였다. Flat TDR 시스템은 지반의 교란을 일으키기 않는 장비로써 측정값을 검증하기 위하여 주문진표준사 외 7개소의 현장대상지반의 시료에 대하여 건조밀도와 함수비를 측정하였다. 함수비구간은 3, 6, 9, 12, 15, 18%의 6개 구간으로 나누어 측정을 하였으며 실험결과는 통일분류법에 따라 확인하였다. 실내실험 결과, 함수비는 SP시료의 경우 약 0.7%, SM시료의 경우 약 1.3%의 오차를 보였다. 또한 건조단위중량은 SP시료의 경우 약 7%, SM시료의 경우 약 5%의 오차를 확인하였다. 이는 점토나 자갈을 제외한 모래 또는 실트질 모래지반에서는 안정적인 값을 도출함을 확인할 수 있었다. 실험 결과를 통하여 Flat TDR 시스템의 측정값이 기존의 전통적인 다짐관리방법과 유사한 값을 도출하는 것을 확인할 수 있었고 이는 빠른 시공성과 경제성을 필요로하는 건설현장에서 Flat TDR 장비가 적합하다는 것을 판단할 수 있었다.

키워드
TDR
flat TDR
다짐시험
함수비
건조단위중량

In this study was conducted to measure the water content and dry unit weight of the ground using TDR (Time Domain Reflectometry) in order to supplement the problems of the conventional compaction management method. The Flat TDR system is a device that does not cause ground disturbance, and in order to verify the measured values, the dry density and water content were measured for samples of the ground subject at 7 sites other than Jumunjin Standard Temple. The water content section was divided into 6 sections of 3, 6, 9, 12, 15, and 18%, and the experimental results were confirmed according to the unified classification method. As a result of the indoor experiment, the water content showed an error of about 0.7% for the SP sample and about 1.3% for the SM sample. In addition, the dry unit weight confirmed an error of about 7% for the SP sample and about 5% for the SM sample. It was confirmed that stable values ​​were derived in sandy or silty sandy ground except for clay or gravel. Through the experimental results, it was confirmed that the measured values ​​of the flat TDR system derive similar values ​​to the existing traditional compaction management method, and it was determined that the flat TDR equipment was suitable for construction sites that require quick constructability and economic feasibility.

Keywords
TDR
flat TDR
compaction test
water ratio
drying unit weight
References
1
ASTM D6780-05, 2005, Standard test method for water content and density of soil in place by time domain reflectometry (TDR), Annual Book of ASTM Standards.
2
Ferré, P.A., Knight, J.H., Rudolph, D.L., Kachanoski, R.G., 1998, The sample areas of conventional and alternative time domain reflectometry probes, Water Resources Research, 34(11), 2971-2979. 10.1029/98WR02093
3
Giese, K., Tiemann, R., 1975, Determination of the complex permittivity from thin-sample time domain reflectometry improved analysis of the step response waveform, Advances in Molecular Relaxation Processes, 7(1), 45-59. 10.1016/0001-8716(75)80013-7
4
Jung, S., Drnevich, V., Abounajm, M., 2013, New methodology for density and water content by time domain reflectometry, Journal of Geotechnical and Geoenvironmental Engineering, 139(5), 659-670. 10.1061/(ASCE)GT.1943-5606.0000783
5
Knight, J.H., Ferré, P.A., Rudolph, D.L., Kachanoski, R.G., 1997, A numerical analysis of the effects of coatings and gaps upon relative dielectric permittivity measurement with time domain reflectometry, Water Resources Research, 33(6), 1455-1460. 10.1029/97WR00435
6
Sallam, A.M., White, N.K., Ashmawy, A.K., 2004, Evaluation of the purdue TDR method for soil water content and density measurement, No. BC-353-30.
7
Siddiqui, S.I., Drnevich, V.P., Deschamps, R.J., 2000, Time Domain 1. Reflectometry development for use in geotechnical engineering, Geotechnical Testing Journal, 23(1), 99-20. 10.1520/GTJ11119J
8
Song, M.W., 2016, Development of nondestructive measurement system for estimating geotechnical properties of soils, Master Thesis, Chosun University, 1-118 (in Korean with English abstract).
9
Song, M.W., Choi, C.Y., Kim, D.H., 2016, Development of a flat-type TDR system for compaction control, Journal of the Korean Geotechnical Society, 32(4), 51-61 (in Korean with English abstract). 10.7843/kgs.2016.32.4.51
10
Song, M.W., Kim, D.H., Choi, C.Y., 2015, A new calibration equation for predicting water contents with TDR, Journal of the Korean Geosynthetics Society, 14(1), 59-65 (in Korean with English abstract). 10.12814/jkgss.2015.14.1.059
11
Thring, L.M., Boddice, D., Metje, N., Curioni, G., Chapman, D.N., Pring, L., 2014, Factors affecting soil permittivity and proposals to obtain gravimetric water content from time domain reflectometry measurements, Canadian Geotechnical Journal, 51(11), 1303-1317. 10.1139/cgj-2013-0313
12
Topp, G.C., Davis, J.L., Annan, A.P., 1980, Electromagnetic determination of soil water content: measurements in coaxial transmission lines, Water Resources Research, 16(3), 574-582. 10.1029/WR016i003p00574
13
Yu, X., Drnevich, V.P., 2004, Soil water content and dry density by time domain reflectometry, Journal of Geotechnical and Geoenvironmental Engineering, 130(9), 922-934. 10.1061/(ASCE)1090-0241(2004)130:9(922)
14
Yu, X., Yu, X., 2006, Time domain reflectometry tests of multilayered soils, Proc. TDR, Purdue University, 1-16.
Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 31
  • No :3
  • Pages :333-342
  • Received Date :2021. 08. 23
  • Accepted Date : 2021. 08. 31
  • DOI :https://doi.org/10.9720/kseg.2021.3.333
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