• Title/Summary/Keyword: compaction control

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Assessment of Subsoil Compaction by Soil Texture on Field Scale

  • Cho, Hee-Rae;Jung, Kang-Ho;Zhang, Yong-Seon;Han, Kyung-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.6
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    • pp.628-633
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    • 2015
  • It is necessary to assess soil physical properties and crop growth treated by compaction to establish the soil management standard. This study evaluated the bulk density, strength and crop growth after subsoil compaction for sandy loam and loam on the field in Suwon, Korea. The treatments were compaction and deep tillage. Sandy loam and loam were classified to coarse soil and fine soil, respectively, depending on clay contents. In coarse soil, bulk density of compacted plot was 8~17% greater than control and deep tilled plot. The root growth was worse in compacted plot compared with control. In fine soil, plow pan was not observed in deep tilled plot with 5~19% smaller bulk density than compacted plot and control. Deep tillage improved the crop growth. The soil physical properties by compaction were dependent on clay content and crop growth limit depended on the traffic driving.

Site-specific Quantification and Management of Soil Compaction: A Review (토양 다짐 변이 측정 및 관리기술에 관한 연구동향)

  • Chong, B.H.;Chung, S.O.
    • Journal of Biosystems Engineering
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    • v.31 no.1 s.114
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    • pp.24-32
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    • 2006
  • Compaction is becoming a greater concern in crop production and the environment because it can have deleterious effects on growing conditions that are difficult to remediate. Because compaction can vary considerably from point to point within a field, and also from depth to depth within the soil profile, it is important to consider quantification and management of the spatial and vertical variability in soil compaction when developing an overall site-specific crop management plan. In this paper, the importance of soil compaction, techniques for quantification of its variability, and the concept of site-specific tillage are examined. Methods and systems to detect within-field variation in soil strength as a surrogate measure of soil compaction and related soil properties are also compared and discussed. Quantification of variability in soil compaction and site-specific compaction management was motivated recently, and sensors and control systems are still under development. Future study will need to address a number of issues related to understanding and applying the sensor measurements.

Reinforcement of the Structure Foundation using Grouting(C.G.S) (그라우팅(C.G.S)에 의한 구조물 기초 보강)

  • 천병식;김진춘;권형석
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.02a
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    • pp.1-11
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    • 2000
  • The use of Compaction Grouting evolved in 1950's to correct structural settlement of buildings. Over the almost 50 years, the technology has been developed and is currently used in wide range of applications. Compaction Grouting, the injection of a very stiff, 'zero-slump' mortar grout under relatively high pressure, displaces and compacts soils. It can effectively repair natural or man-made soil strength deficiencies in variety of soil formations. Major applications of Compaction Grouting include densifying loose soils or fill voids caused by sinkholes, poorly compacted fills, broken utilities, improper dewatering, or soft ground tunneling excavation. Other applications include preventing liquefation, re-leveling settled structures, and using compaction grout bulbs as structural elements of minipiles or underpinning. In this paper, on the basis of the case history constructed in this year, a study has been performed to analyze the basic mechanism of the Compaction Grouting. Also, the effectiveness of the ground improvement and the bearing capacity of the Compaction Pile has been verified by the Cone Penetration Test(CPT) and Load Test. Relatively uniform Compaction grouting column could be maintained by planning the Quality Control in the course of grouting. And, the Quality Control Plan has been conceived using grout pressure, volume of grout and drilling depth.

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A Tentative Methodology for Quality Control of Trackbed Fills Using Field and Laboratory P-Wave Measurements

  • Park, Chul-Soo;Park, In-Beom;Kim, Eun-Jung;Mok, Young-Jin
    • International Journal of Railway
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    • v.1 no.2
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    • pp.64-71
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    • 2008
  • The quality of track-bed fills of railways has been controlled by field measurements of density $({\gamma}_d)$ and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The Key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of OMC${\pm}$2% as well as the p-wave velocity.

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A Study on Analysis Method for Roller Compaction Work (다짐공사에 대한 롤러의 효율적 품질관리 방안 연구)

  • Lee, Soo Min;Lee, Seung Soo;Yu, Sang Hoon;Seo, Jong Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.3
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    • pp.621-627
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    • 2017
  • In this study, GPS (Global Positioning System) is applied to rollers for quality control problems caused by empirical judgment of compaction construction. In addition, database and 3D modeling of location information can eliminate unnecessary compaction or excessive compaction, thereby improving quality and shortening the time. This paper presents a methodology of ICMV (Intelligent Compaction Measurement Values) analysis by designing a intelligent compaction method using an accelerometer. Detailed method of ICMV analysis includes CMV (Compaction Meter Value) analysis which can quickly and conveniently evaluate the compaction of the compacted ground.

Study on Establishing the Subgrade Compaction Control Methods Based on the In-situ Elastic Modulus (현장 탄성계수에 근거한 노상 다짐관리방안 연구)

  • Choi, Jun-Seong;Han, Jin-Seok;Kim, Jong-Min
    • International Journal of Highway Engineering
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    • v.14 no.3
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    • pp.49-58
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    • 2012
  • In many countries including Korea, the design concept of pavement structure has been converted from empirical method to mechanisticempirical method since the advent of compaction control based on resilient modulus proposed by AASHTO in 1986. Studies of last decades indicates that the classical compaction control method based on relative compaction and plate bearing test(PBT) will necessarily move to the methods taking advantage of light falling weight deflectometer(LFWD) and dynamic cone penetrometer(DCP) in addition to PBT. In this study, the validity of resilient modulus prediction equation proposed by Korean Pavement Design Guide is verified by comparison with physical properties of subgrade soil and the results of structural analysis. In addition, correlational equations between elastic modulus measured by various field tests and resilient modulus estimated by empirical model are proposed. Finally, a field test-based compaction control procedure for subgrade is suggested by using proposed correlational equations.

Investigation of Domestic Application for Soil Impact Hammer(SIH) (동적 지반물성측정장치(SIH, Soil Impact Hammer)의 국내 적용성 평가)

  • 박재영;석정우;황대진;양구승
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.10a
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    • pp.411-418
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    • 2002
  • In domestic road construction sites, the compaction control based on strength are widely performed through the direct method with high accuracy, such as Plate Loading Test or Field CBR test. It is impossible to manage all construction sites using the direct method because the direct method requires heavy reaction loads and long measurement time. Therefore, it is necessary to apply the indirect method that could control the relative density of construction sites on the whole. Indirect methods, such as Cone Penetration Test and Fall Cone Test, require extra time for data analyzing and fixed area for test device. In this paper, the field applicability of Soil Impact Hammer (SIH) was investigated comparing with the results of field measurement tests and laboratory compaction tests. SIH developed by Japan Construction Administration and Asanuma Ltd., is a kind of indirect methods for compaction checking. According to the results of SIH performed in domestic road construction site, the subgrade reaction modulus obtained from SIH are similar to that from Plate loading tests in the range of 10 to 40. In comparison with laboratory compaction test, similar compaction line are shown in the dry side of optimum moisture contents.

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Plastic deformation characteristics of disintegrated carbonaceous mudstone under dynamic loading

  • Qiu, Xiang;Yin, Yixiang;Jiang, Huangbin;Fu, Sini;Li, Jinhong
    • Geomechanics and Engineering
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    • v.31 no.1
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    • pp.87-97
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    • 2022
  • The excessive settlement and deformation of disintegrated carbonaceous mudstone (DCM) embankments under dynamic loading have long been problems for engineers and technicians. In this work, the characteristics and mechanism of the plastic deformation of DCM under different degrees of compaction, water contents and confining pressures were studied by static triaxial, dynamic triaxial and scanning electron microscopy testing. The research results show that the axial stress increases with increasing confining pressure and degree of compaction and decreases with increasing water content when DCM failure. The axial strain at failure of the DCM decreases with increasing confining pressure and degree of compaction and increases with increasing water content. Under cyclic dynamic stress, the change in the axial stress level of the DCM can be divided into four stages: the stable stage, transition stage, safety reserve stage and unstable stage, respectively. The effects of compaction, water content and confining pressure on the critical axial stress level which means shakedown of the DCM are similar. However, an increase in confining pressure reduces the effects of compaction and water content on the critical axial stress level. The main deformation of DCM is fatigue cracking. Based on the allowable critical axial stress, a method for embankment deformation control was proposed. This method can determine the degree of compaction and fill range of the embankment fill material according to the equilibrium moisture content of the DCM embankment.

Development of Intelligent Compaction System for Efficient Quality Control (효율적 품질관리를 위한 지능형 다짐 시스템 개발)

  • Lee, Soomin;Park, Sangil;Lee, Riho;Seo, Jongwon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.38 no.5
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    • pp.751-760
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    • 2018
  • Currently, the quality measurement of the work is carried out by the supervisor's visual inspection, as the workers individually judge the number of resolutions, thickness, speed and vibration. After work, we are conducting follow-up work through traditional spot test, which is less representative. Therefore, it is impossible to check the results of the resolution, and there is always the possibility that problems will arise due to poor construction. This study demonstrates the feasibility of using the continuous compaction strength measurement method by comparing the continuous compaction strength measurement method and the conventional compaction strength measurement method after performing the compaction in the actual field scale in various test conditions. The validity is verified by analyzing the Compaction Meter Value of an Intelligent Compaction roller composed of a Global Positioning System and an accelerometer, Based on the proven results, a full range of quality can be confirmed without a single test. The quality confirmation is visualized in the compaction control program developed in this study, This enables the field manager to perform real-time quality monitoring at the same time as compaction.