• 제목/요약/키워드: settlement foundation

검색결과 454건 처리시간 0.023초

모형시험에 의한 점성토 보강토벽의 거동분석 (Analgesis of Clearly Reinforced Soil Wall Behavior by Model Test)

  • 이용안;이재열;김유성
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 토목섬유 학술발표회 논문집
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    • pp.85-94
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    • 1999
  • Reinforced Soil Wall has several merits comparing with conventional retaining wall. The conventional method has the limit of wall height, ununiform settlement of the foundation ground, quality assurance of the embankment body, shortening of construction period, economical construction and so on. Basis of previous mentioned things reinforced soil wall is the substitutional method of conventional retaining wall and its necessity is continuously increasing. The embanking material used in reinforced soil wall is generally limited such as a good quality sandy soil, and in many case constructors have to transfer such a good embanking material from far away to construction site. As a result, they would pressed by time and economy. If poor soils could be used embanking material, for example, clayey soil produced in-situ by cutting and excavation, the economical merit of reinforced soil wall would be increased more and more. Likewise, a lot of study about laboratory experimental behavior of reinforced soil wall using a good quality soil is being performed, but is rare study about clayey soil containing much volume of fine particle relatively in korea. In this study, the authors investigated behavior of the geosynthetic reinforced and unreinforced soil walls using clayey soil as embanking material in view of horizontal movement of walls, bearing capacity and reinforcement stress.

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

  • 천병식;김진춘;권형석
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 연약지반처리위원회 학술세미나
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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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풍화암 지반에 설치된 소구경말뚝의 거동에 관한 연구 (An Experimental Study on the Behavior of Miscopiles installed in Weathered Weak Rock)

  • 박성재;정경환;이세훈
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.389-396
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    • 1999
  • In this study compressive and tensile load tests have been performed to investigate reinforcing effect and load transfer mechanism of small diameter piles installed in the foundation soil for the marine suspension bridge. Load tests were carried out on steel plate with diameters of 50cm, 100cm and 150cm varying loads starting from 39 tons up to 314 tons. Small diameter piles were proved to behavior like as friction piles and loads were not transmitted to the bottom of piles. From pull-out tests, the uplift capacity of small diameter piles was largely influenced by reinforcing materials compared to frictional resistance between piles and adjacent soils. The bearing capacity of small diameter piles appeared to be higher than the ultimate bearing capacity evaluated using static formulae. The load carrying capacity of small diameter piles was superior to the bored piles with a similar size. Thus, ultimate bearing capacity estimated from static formulae can provide conservative designs and thereby resulting in economic disadvantages. A further study to accumulate data regarding various soil conditions is recommended for an improved estimation of bearing capacity of piles with small diameter.

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연약지반 상 노상다짐 방법 개선에 대한 연구 (A Study on Improvement of Road Compaction Method in Soft Ground)

  • 최현석;장호훈
    • 지질공학
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    • 제29권4호
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    • pp.427-437
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    • 2019
  • 본 연구의 목적은 대단위 연약지반 조성지역에서 도로를 건설할 때 노체층까지 다짐시공 후 압밀처리기 간완료에 따른 여성토를 제거하고 노상층을 시공하므로 공사비용, 시간, 현장관리 등의 문제점을 개선하고자 하였다. 노상층을 연약지반 개량 전에 선시공하여 여성고에 포함시키고 압밀침하 완료 후 선시공된 노상층의 다짐도 유지유무를 현장시험을 통하여 확인하였다. 실험결과, 제 1노상층을 제외한 모든 노상층은 일정하게 유지되었다. 따라서 제 1노상층을 제외하고 시공한다면 도로건설에서 경제적 시공성을 확보하는 것이 유리한 것으로 판단된다.

대형평판재하시험의 지중응력 측정결과를 이용한 연암의 변형계수 산정 (Estimation of deformation modulus for rock mass using stress distribution under ground in Large Plate Load Test)

  • 박원태;이민희;최용규;김석찬;김정환
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.539-545
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    • 2010
  • The field plate test has a good potential for determining since it measures both plate pressure and settlement. The deformation modulus of rock mass is differently measured for status of structures. The values of deformation modulus are obtained from laboratory test (uniaxial and triaxial test) and field test (pressuremeter test). Plate load test should be conducted by different loading plate sizes for geological structure of rock mass and scale of structures. In this paper, large plate load tests were performed to predict of structure's behavior and evaluate the ultimate bearing capacity of the foundation on soft rock. Simultaneously, deformation modulus of rock mass was estimated by back analysis of stresses measured in field test under rock mass. Finally, we verified the validation of deformation modulus of rock mass through result of large plate load test and numerical simulation.

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An analytical analysis of a single axially-loaded pile using a nonlinear softening model

  • Wu, Yue-dong;Liu, Jian;Chen, Rui
    • Geomechanics and Engineering
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    • 제8권6호
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    • pp.769-781
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    • 2015
  • The skin friction of a pile foundation is important and essential for its design and analysis. More attention has been given to the softening behaviour of skin friction of a pile. In this study, to investigate the load-transfer mechanism in such a case, an analytical solution using a nonlinear softening model was derived. Subsequently, a load test on the pile was performed to verify the newly developed analytical solution. The comparison between the analytical solution and test results showed a good agreement in terms of the axial force of the pile and the stress-strain relationship of the pile-soil interface. The softening behaviour of the skin friction can be simulated well when the pile is subjected to large loads; however, such behaviour is generally ignored by most existing analytical solutions. Finally, the effects of the initial shear modulus and the ratio of the residual skin friction to peak skin friction on the load-settlement curve of a pile were investigated by a parametric analysis.

연약지반상 팽이기초 적용에 따른 지지특성 (The Bearing Capacity of Top Base Foundations in Soft Ground)

  • 김찬국;김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.401-414
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    • 2010
  • Top Base Foundation(TBF) is a stabilization method for light weight structures particularly in the soft ground. It is widely used for the increment of bearing capacity and restraining settlement of foundations when the bearing capacity of ground is not enough. However, when the design values from exiting Japanese standard are compared with the observation values from the field measurement, the bearing capacity of exiting standard estimated smaller For this reason, it is necessary to establish more reasonable prediction technique considering to understand the behavior of TBF in soft ground. In this study, 1/5 scale model tests were performed in the laboratory. Also, full scale tests were carried out in order to investigate the behavior of TBF with various shapes. In addition, about 100 sites measurement data were evaluated to investigate the behavior of TBF in various ground conditions. Based on the results of the model tests and field measurement data, it was possible to establish more reasonable the bearing capacity equation of TBF considering various N-value of soil, the effect of underground water and failure shapes.

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New horizon of earth reinforcement technique - current and future -

  • Otani, Jun
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2007년 가을학술발표회
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    • pp.514-527
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    • 2007
  • Earth reinforcement techniques are used worldwide and offer proven solutions to a wide range of geotechnical engineering problems. Here in this paper, recent developments of three major reinforced soil retaining wall methods in Japan were introduced in order to show how the current situation of this technique in Japan is. And the statistical data for the volume of the use was also shown, such as the total volume of the use, the scales of the structures, layout of the earth reinforcement, fill materials, and foundation conditions. Some of the case histories were also introduced with photographs and figures. And then, as one of recent research activity by the author, the study on the application of X-ray CT for the problem of earth reinforcement method combined with other method such as piling and soil improvement was introduced. In this study, a series of model test for several reinforced ground with geogrids was conducted using a newly developed test apparatus. Then, the behavior in the soil box was scanned after settlement using X-ray CT scanner. Based on these test results, the reinforcing effect by the geogrids and the soil arching effect over the pile heads was discussed precisely and those are done in 3-D with nondestructive condition. Finally, the effectiveness of the use of X-ray CT scanner in geotechnical engineering was promised.

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DCM 공법에 의한 방파제 기초 적용사례 (Application to Breakwater Foundation by DCM)

  • 구임식;김영상;정경환;최정욱;신민식;김재현
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.372-382
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    • 2006
  • The DCM(Deep Cement Mixing) Method was introduced domestically in 1985 and has been applied widely to improve stability, increase bearing capacity and reduce settlement of the structure. It has been only performed by the combined equipment to improve the soft ground in coastal areas. But it has qualify-control problems such as interference of waves and improving depth, etc. Therefore DCM Barge of specialist equipment, named by Dong Ji Ho, was equipped with three mixing shafts with four rod and installed GPS system In itself, had been developed in 2005 for the purpose of solving the above problems. This paper represents about Dong Ji Ho's qualify-control system as well as it's first domestic application to in-situ trial test and the original design of the Ulsan breakwater site.

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Animal-Hide Clothing and Decorative Arts of the Oroqen People

  • Wu, Yazhi;Kim, In Hee;Cho, Woo Hyun
    • International Journal of Costume and Fashion
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    • 제16권2호
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    • pp.67-79
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    • 2016
  • The Oroqen (鄂伦春) traditional costume refers to what the nomadic Oroqen people used to wear before they settled into fixed communities. With very limited contact with the outside world and with limited resources, the clothing material was virtually entirely animal hide. With settlement, especially after 1996, animal hide clothing has declined among the Oroqen. As an important part of Oroqen tradition and culture, the Oroqen people keep endevoring to promote costume design through competition and exhibitions. Therefore, this paper seeks to present an insightful understanding of Oroqen culture and the formative features of their general clothing. We explored the formative features of Oroqen animal hide clothing based on an analysis of actual artifacts and literature. As a result, the characteristics of Oroqen hide clothing were found in five types - coats, trousers, hats, shoes, gloves. For the decoration, embroidery and applique were their way of decoration, and Mother Nature was their source of pattern design.