• Title/Summary/Keyword: Field lateral loading test

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A Study on Lateral Loading the Field Test of Pile for Large Diameter Drilled Shaft Pile (대구경 현장타설말뚝에 대한 현장수평재하시험에 관한 연구)

  • Choi, Yong-Kyu;Lee, Min-Hee;Lee, Chung-Sook
    • Journal of the Korean GEO-environmental Society
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    • v.5 no.2
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    • pp.33-39
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    • 2004
  • Most of pile foundations are a condition of fixed head on pile, but lateral loading test of pile have performed to free head on generally. This study performed field lateral loading test accompanying lateral displacement by depth of pile for two cases(fixed head and free head) and analyzed lateral behavior of large drilled shaft. Furthermore compared theoretical equation with result of lateral loading test.

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A Study on the Estimation of the Coefficient of Horizontal Subgrade Reaction for Sandy Soil by Field Tests (현장시험에 의한 사질지반의 수평방향 지반반력계수 추정에 관한 연구)

  • Cheon, Byeong-Sik;Seo, Deok-Dong;Jang, Young-Sang;An, Ik-Kyun;Lee, Jin-Goo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.641-652
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    • 2005
  • In this paper, the Coefficient of Subgrade Reaction was analyzed from the data which were the results of lateral pile loading tests and pressuremeter tests on construction sites. The prediction method with N-value was compared with lateral pile loading tests and the results of lateral pile loading tests were compared with the prediction method considering diameter of a pile. Also, the results of lateral pressuremeter tests were compared with those of lateral pile loading tests. As a result, consideration for a diameter and lateral deformation of a pile was needed when the coefficient of horizontal subgrade reaction is presumed. Therefore, a formula which is taking into account the allowable deformation of a pile was suggested from lateral pressuremeter tests in this study.

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Dilatation characteristics of the coals with outburst proneness under cyclic loading conditions and the relevant applications

  • Li, Yangyang;Zhang, Shichuan;Zhang, Baoliang
    • Geomechanics and Engineering
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    • v.14 no.5
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    • pp.459-466
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    • 2018
  • By conducting uniaxial loading cycle tests on the coal rock with outburst proneness, the dilatation characteristics at different loading rates were investigated. Under uniaxial loading and unloading, the lateral deformation of coal rock increased obviously before failure, leading to coal dilatation. Moreover, the post-unloading recovery of the lateral deformation was rather small, suggesting the onset of an accelerated failure. As the loading rate increased further, the ratio of the stress at the dilatation critical point to peak-intensity increased gradually, and the pre-peak volumetric deformation decreased with more severe post-peak damage. Based on the laboratory test results, the lateral deformation of the coals at different depths in the #1302 isolated coal pillars, Yangcheng Coal Mine, was monitored using wall rock displacement meter. The field monitoring result indicates that the coal lateral displacement went through various distinct stages: the lateral displacement of the coals at the depth of 2-6 m went through an "initial increase-stabilize-step up-plateau" series. When the coal wall of the working face was 24-18 m away from the measuring point, the coals in this region entered the accelerated failure stage; as the working face continued advancing, the lateral displacement of the coals at the depth over 6 m increased steadily, i.e., the coals in this region were in the stable failure stage.

A Study on Maximum Tensile Strain of Vehicle Speeds in Flexible Pavement (차량속도에 따른 연성 포장의 최대인장변형률에 관한 연구)

  • Jo, Myoung-Hwan;Kim, Nak-Seok;Choi, Ho-Geun;Seo, Young-Guk
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.329-332
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    • 2008
  • This study presents a viscoelastic characterization of flexible pavement subjected to moving loads. A series of field tests have been conducted on three pavement sections (A2, A5, and A8) at the Korea Expressway Corporation (KEC) test road. The effect of vehicle speed on the responses of each test section was investigated at three speeds: 25km/hr, 50km/hr, and 80km/hr. During the test, both longitudinal and lateral strains were measured at the bottom of asphalt layers and in-situ measurements were compared with the results of finite element (FE) analyses. A commercial FE package was used to model each test section and a step loading approximation has been adopted to simulate the effect a moving vehicle. Field responses reveal the strain anisotropy (i.e., discrepancy between longitudinal and lateral strains) and the amplitude of strain normally decreases as the vehicle speed increases. In most cases, lateral strain was smaller than the longitudinal strain, and strain reduction was more significant in lateral direction.

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Analysis of Composite Pile Behavior under Lateral Loadings (수평재하에 따른 복합말뚝의 거동분석)

  • Hwang, Taik-Jean
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.3
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    • pp.1396-1404
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    • 2012
  • A composite pile consisted of a concrete lower part with a steel tubular pile at upper part was installed by pre-drilling method. Seven pairs of strain gauges and inclinometer were attached on the pile in order to measure stresses and displacement along the pile during the lateral loading test. The results of instrumentation were analyzed using various theoretical approaches. The back analysis showed that the measured stresses were smaller than those of the calculated. The maximum stress is measured at the steel upper part and decreased rapidly with depth of the pile. The calculated lateral displacement along the pile provide very good agreement with the measured values if the coefficient of subgrade reaction is selected properly. The design concept of a composite pile is verified by the measured stresses and displacement which is within the tolerable limits of the pile.

Field Evaluation of Traffic Wandering Effect on Asphalt Pavement Responses (차량의 횡방향 주행이격에 의한 아스팔트 콘크리트 포장의 응답특성 분석)

  • Seo, Youngguk;Kwon, Soon-Min;Lee, Jae-Hoon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.3D
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    • pp.453-459
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    • 2006
  • This paper presents an experimental evaluation of wandering effect on asphalt concrete pavement responses. A laser-based wandering system has been developed and its performance is verified under various field conditions. The portable wandering system composed of two laser sensors with Position Sensitive Devices can allow one to measure the distance between laser sensors and tire edges of moving vehicle. Therefore, lateral position of each wheel on the pavement can be determined in a real time manner. Pavement responses due to different loading paths are investigated using a roll over test which is carried out on one of asphalt surfaced pavements in the Korea Highway Corporation test road. The pavement section (A5) consists of 5 cm thick surface course; 7 cm intermediate course; and 18 mm base course, and is heavily instrumented with strain gauges, vertical soil pressure cells and thermo-couples. From the center of wheel paths, seven equally-spaced lateral loading paths are carefully selected over an 140 cm wandering zone. Test results show that lateral horizontal strains in both surface and intermediate courses are mostly compressive right under the loading path and tensile strains start to develop as the loading offset becomes 40 cm from the wheel path. The development of the vertical stresses in the top layers of subbase and anti-frost is found to be minimal once the loading offset becomes 50 cm.

Lateral Resistance Analysis of Single Pile Using Strain Wedge Model in Sand (모래지반에서 쐐기모델을 이용한 단독말뚝의 수평저항력 해석)

  • Bae, Jong-Soon;Kim, Ji-Seong;Kim, Sung-Ho
    • Journal of the Korean Geotechnical Society
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    • v.26 no.11
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    • pp.39-46
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    • 2010
  • The magnitude of the lateral resistance that resists the lateral movement of the pile is controlled by the amount of the pile movement and the strength and stiffness of soil. In this paper, we proposed an equation which produces the lateral resistance of the laterally loaded single pile using the strain wedge model of the soil deformation. The results of this equation is compared with results of model test, field test, p-y curve and other methods. It is found that the result of proposed equation is smaller than the result of model test. The results of loading test considerably coincide with those of proposed equation; however, a few of deviations are generated as the displacement of pile head increases. Moreover, coincidences exist between the results of the proposed equation and those of finite difference method.

Asphalt Concrete Pavement Response to Moving Load and Viscoelastic Property (아스팔트 혼합물의 점탄성과 차량의 이동 속도가 포장 거동에 미치는 영향)

  • Jo, Myoung-hwan;Kim, Nakseok;Seo, Youngguk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.4D
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    • pp.485-492
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    • 2008
  • This study presents a viscoelastic characterization of flexible pavement subjected to moving loads. A series of field tests have been conducted on three pavement sections (A2, A5, and A8) at the Korea Expressway Corporation (KEC) test road. The effect of vehicle speed on the responses of each test section was investigated at three speeds: 25 km/hr, 50 km/hr, and 80 km/hr. During the test, both longitudinal and lateral strains were measured at the bottom of asphalt layers and in-situ measurements were compared with the results of finite element (FE) analyses. A commercial FE package, ABAQUS was used to model each test section and a step loading approximation has been adopted to simulate the effect a moving vehicle. For viscoelastic analysis, relaxation moduli of asphalt mixtures were obtained from laboratory test. Field responses reveals the strain anisotropy (i.e., discrepancy between longitudinal and lateral strains) and the amplitude of strain normally decreases as the vehicle speed increases. In most cases, lateral strain was smaller than longitudinal strain, and strain reduction was more significant in lateral direction.

Lateral confining action of mortar-filled sleeve reinforcement splice

  • Kim, Hyong-Kee;Lee, Sang-Ho
    • Structural Engineering and Mechanics
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    • v.41 no.3
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    • pp.379-393
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    • 2012
  • Of the various methods of splicing reinforcing bar in reinforced concrete structure, mortar-filled sleeve reinforcement splice offers diverse benefits, not only in terms of structural performance but also for the construction process. Consequently, after the mortar-filled sleeve splices have been developed in recent years, research and development on these splices has been actively carried out, in order to evaluate its macro structural performance, such as its strength and stiffness, with the aim of enabling this system to be applied to construction in the field as early as possible. However, to make a proper evaluation on the overall structural performance of the mortar-filled sleeve reinforcing bar splice, it is of critical importance to understand the lateral confining action of the sleeve, which is known to affect the bond strength between the embedded bar and mortar in the sleeve. Accordingly, in this study, an experiment of monotonic loading and cyclic loading was conducted with a full-sized mortar-filled sleeve splice attaching strain gauges on the sleeve surface with experimental variables such as development length of bar, etc. Based on the test results, the effect of the lateral confining action of the sleeve was analyzed and considered in terms of the bond strength between the bar and mortar in this splice.

A Study on Numerical Analysis of Flexible Pavements under Moving Vehicular Loads (차량의 이동하중을 고려한 연성포장의 수치해석 기법 연구)

  • Park, Seoksoon;Kim, Nakseok
    • Journal of the Society of Disaster Information
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    • v.7 no.3
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    • pp.206-219
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    • 2011
  • The important elements in pavement design criteria are the stress and strain distributions. To obtain reasonable stress and strain distribution, tire contact area and tire pressures are very important. This study presents a viscoelastic characterization of flexible pavement subjected to moving loads. During the test, both longitudinal and lateral strains were measured at the bottom of asphalt layers and in-situ measurements were compared with the results of numerical analysis. A 3-dimension finite element model was used to simulate each test section and a step loading approximation has been adopted to analyze the effect of a moving vehicle on pavement behaviors. For viscoelastic analysis, relaxation moduli, E(t), of asphalt mixtures were obtained from laboratory test. Field responses reveal the strain anisotropy (i.e., discrepancy between longitudinal and lateral strains), and the amplitude of strain normally decreases as the vehicle speed increases. In most cases, lateral strain was smaller than longitudinal strain, and strain reduction was more significant in lateral direction.