• 제목/요약/키워드: Pile load capacity

검색결과 465건 처리시간 0.023초

선단지지된 항타개단강관말뚝의 축하중전이거동 (Axial Load Transfer Behavior for Driven Open-ended End bearing Steel Pipe Pile)

  • 임태경;정성민;정창규;최용규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.589-596
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    • 2002
  • In this study, static pile load tests with load transfer measurement were accomplished in the field. Yield pile capacity (or ultimate pile capacity) determined by load-settlement-time relationship was determined and axial load transfer behavior was analyzed. In the test for the four test piles were behaved as end bearing pile but ratios of skin friction to total pile capacity were 27%∼33%.

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산정방법에 따른 단말뚝의 지지력 비교연구 (A Comparative Study on Bearing Capacity of Single Pile Based on Calculation Method)

  • 이영대;심재현
    • 한국농공학회지
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    • 제39권2호
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    • pp.124-133
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    • 1997
  • Pile load test is good for estimating pile bearing capacity, but using this method is limited by time and cost required. Dynamic and static method is more convenient and economical, but confidence of estimated value by dynamic and static method are lower than that of pile load test. After being compared pile bearing capacity data obtained from pile load test with those of other two methods, the results from this study were summarised as follows. For allowable bearing capacity values greater than 175t per pile, bearing capacity acquired from static method was higher than that acquired from pile load test, whereas bearing capacity acquired from pile load test was higher than that acquired from static method for values under 175 per pile. It was that variance of bearing capacity was large when bearing capacity obtained by dynamic method was higher than 250t. Also bearing capacity based on dynamic method was higher than that based on pile load test. Allowable bearing capacity get from dynamic method suggested that carefull precautions are necessary in application for allowable bearing capacity values higher than 2S0ton per pile.

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양방향말뚝재하시험의 재하용량 기준 설정을 위한 사례분석 연구 (A study on case analysis for loading capacity standard establishment of bi-directional pile load test (BD PLT))

  • 최용규;서정혜;김상일
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.377-384
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    • 2008
  • In the bi-directional pile load test (BD PLT) for pile load test of Mega foundation, loading capacity specification were not specified exactly. Therefore there are so many confusions and variations of maximum 2 times in loading capacity are come out. In this study, specifications of bi-directional pile load test (BD PLT) were considered. Based on cases of the bi-directional pile load test performed in domestic areas, maximum equivalent test load, test load increasing ratio and sufficiency ratio of design load were analyzed. It can be known that the loading capacity specification of bi-directional pile load test must be defined as 1-directional test load that is established as more than 2 times of design load.

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말뚝 기초지지력에 대한 안전율과 신뢰도지수 평가 (Relations of Safety Factor and Reliability Index for Pile Load Capacity)

  • 김대호;이준환
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.466-475
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    • 2006
  • Reliability analysis between safety factor and reliability index for driven and bored pile load capacity was analyzed in this study. 0.1B, Chin, De Beer, and Davisson's methods were used for determining pile load capacity by using load-settlement curve from pile load test. Each method define ultimate, yield and allowable pile load capacities. LCPC method using CPT results was performed for comparing with results of pile load test. Based on FOSM analysis using load factors, it is obtained that reliability indices for ultimate pile load capacity were higher than those of yield and allowable condition. Present safety factor 2 for yield and allowable load capacities are not enough to satisfy target reliability index $2.0\sim2.5$. However, it is sufficient for ultimate pile load capacity using safety factor 3.

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유한차분법을 이용한 말뚝의 하중전이특성 및 해석기법 (Analytical Technique and Load Transfer Features on Pile Using Finite Difference Method)

  • 한중근;이재호
    • 한국환경복원기술학회지
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    • 제9권5호
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    • pp.10-21
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    • 2006
  • For analyze of the bearing capacity, skin friction and settlements of pile on axial compressive loading, both Load transfer tests of pile and pile loading test in field have application to commonly before pile installing. A bearing capacity of pile was affected by the characteristics of surrounding ground of pile. Especially, that is very different because of evaluation of settlement due to each soil conditions of ground depths. The ground characteristics using evaluation of bearing capacity of pile through load transfer analysis depends on N values of SPT, and then a bearing capacity of pile installed soft ground and refilled area may be difficult to rational evaluation. An evaluation of bearing capacity on pile applied axial compressive loading was effected by strength of ground installed pile, unconfined compressive strength at pile tip, pile diameter, rough of excavated surface, confining pressure and deformation modules of rock etc and these are commonly including the unreliability due to slime occurred excavation works. Load transfer characteristics considered ground conditions take charge of load transfer of large diameter pile was investigated through case study applied load transfer tests. To these, matrix analytical technique of load transfer using finite differential equation developed and compared with the results of pile load test.

폐색정도를 고려한 개단말뚝의 지지력 산정 (Estimation of Bearing Capacity for Open-Ended Pile Considering Soil Plugging)

  • 백규호
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.397-404
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    • 2002
  • The bearing capacity of open-ended piles is affected by the degree of soil plugging, which is quantified by the IFR. There is not at present a design criterion for open-ended piles that explicitly considers the effect of IFR on pile load capacity In order to investigate this effect, model pile load tests using a calibration chamber were conducted on instrumented open-ended piles. The results of these tests show that the IFR increases with increasing relative density and increasing horizontal stress of soils. The unit base and shaft resistances decrease with increasing IFR. Based on the results of the model pile tests, new empirical relations for base load capacity and shaft load capacity of open-ended piles are proposed. In order to check the accuracy of predictions made with the proposed equations, the equations were applied to the full-scale pile load test preformed in this study, Based on the comparisons with the pile load test results, the proposed equations appear to produce satisfactory predictions.

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초고용량 양방향 말뚝재하시험(BDH PLT) 수행사례 분석 (A Case Study of High Capacity Bi-Directional High Pressure Pile Load Test)

  • 김상일;이민희;정성민;정은택;최용규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.1156-1163
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    • 2010
  • The bi-directional high pile load test(BDH PLT) does not have weaknesses found in the existing bi-directional low pile load test(BDL PLT); it has strong economics, is unbound by load capacity limit and secures quality stability of working piles. In this study, Verification the field found a very high capacity level of stability and reliability of the BDH PLT, as well as outstanding field applicability. Field verifications reaffirmed the advantage of the BDH PLT device, which was capable of loading 90 MN capacities as maximum. It was also found to be durable enough to load high capacity with ease.

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침하량과 압축량을 고려한 말뚝의 설계법 개발을 위한 연구 (A Study for the Development of Pile Design Method Considering Settlement and Compression)

  • 임종석;하혁;정상균
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.1287-1294
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    • 2006
  • A pile is compressed with settlements when loading and bearing capacity is altered along relative displacement of pile/soil on settlement and compression. Settlements of pile displaying limit skin friction is different from displaying tip resistance. Therefore, it is an error in traditional method that bearing capacity of pile is estimated from the sum of limit skin fraction and tip resistance. Accordingly, development of design method considering behavior of load-settlement is needed. In this study, we would like to establish the base for development of design method considering bearing capacity altering along displacement on settlement and compression. For this, we established system and substance of design method. And in order to establish relationship of load-settlement of pile on the type of soil, we analyzed and arranged existing database and pile loading test. On design method, settlement is assumed gradually on each capacity level being assumed gradually. Bearing capacity developing on the pile is obtained on each settlement level. Until the obtained bearing capacity will be equal to assumed capacity, this process is continued with increasing settlement. Load-settlement curve for soil classification is sketched in the process computing settlement on assumed capacity. This design method will be materialized by computation program.

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양방향말뚝재하시험의 재하용량 기준에 관한 연구 (A Study on the Loading Capacity Standard of Bi-directional Pile Load Test (BD PLT))

  • 최용규
    • 대한토목학회논문집
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    • 제28권6C호
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    • pp.379-388
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    • 2008
  • 대형말뚝기초의 양방향 재하시험에서 재하용량 기준이 정확하게 규정되어 있지 않다. 그래서 양방향말뚝재하시험을 수행함에 있어 많은 혼란이 발생하고 있으며 재하용량에서 최대 2배까지의 차이가 나타나고 있다. 본 연구에서는 양방향 말뚝재하시험 기준들을 고찰하였으며, 국내에서 수행된 양방향 말뚝재하시험 사례들에 기초하여 최대등가시험하중, 재하하중 증가비, 재하용량 증가비 및 설계하중 충족비를 분석하였다. 양방향 말뚝재하시험 기준은 1방향 재하용량으로 정의되어야 하며, 1방향 재하용량은 설계하중의 2배 이상 이어야 한다는 것을 알 수 있었다.