• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.738-743
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• 2008

Ultimate lateral loaded pile capacity is influenced by soil conditions. Methods of calculating ultimate lateral loaded pile capacity in homogeneous soil were suggested by a lot of previous researchers.(Broms 1964, Petrasovits & Award 1972, Prasad & Chari 1999, Zhang et al. 2005) There is only few homogeneous soil in actual condition, however, it could be not conviction that the methods from previous researchers are correct in multi-layered soil. In this study, the variation of ultimate lateral loaded pile capacity was analyzed in the various multi-layered conditions, ultimate lateral loaded pile capacity was calculated by the methods from previous researchers. For this study, the Lateral Pile Load Tests (LPLT) were performed in calibration chamber, the soil was composed by 3 layers and each layers had a various relative density. The results of LPLT were compared with calculated results from the previous researchers.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.533-538
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• 2009

Ultimate lateral loaded pile capacity is influenced by soil conditions. Methods of calculating ultimate lateral loaded pile capacity in homogeneous soil were suggested by a lot of previous researchers.(Broms 1964, Petrasovits & Award 1972, Prasad & Chari 1999) There is only few homogeneous soil in actual condition, however, it could be not conviction that the methods from previous researchers are correct in multi-layered soil. In this study, ultimate lateral capacities were estimated from artificial multi-layered soils and were measured from lateral load test that were composed by various soil conditions. The influence of layered soil conditions were confirmed by comparing with two results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.253-260
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• 2000

Pile foundations have been widely used in civil engineering construction for many years. Structures subjected to large lateral loads usually have pile foundations as shallow foundations cannot sometimes support the moments on these structure. The purpose of this paper is to propose the p - multiplier factor (P$\sub$M/) based on the characteristics of behavior of laterally loaded group pile in homogeneous sand. For this, a series of model tests are performed and the composite analytical method proposed by author is used to the propose P$\sub$M/. Based on the model test results of the large number of laterally loaded group piles, p - multiplier factors for homogeneous sand are proposed by back analysis under various condition of soil density, spacing-to-diameter ratio of pile, number of pile, and spacing-to-diameter of pile. P - multiplier approach provides a simple but sufficient tool for characterizing the shadowing group effects of laterally loaded group pile.

• 한국지반공학회논문집
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• 제32권12호
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• pp.15-22
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• 2016

본 연구에서는 Strain wedge 해석모델을 이용하여 수평하중이 작용하는 단말뚝의 극한수평저항력 산정식을 제안하였다. 저항특성은 쐐기 후면부의 수평저항토압, 쐐기 측면부의 전단저항, 그리고 말뚝과 지반의 마찰저항으로 구분하였고, 이들의 합으로써 극한수평저항력을 산정하였다. 제안된 식을 기존의 쐐기 이론과 현장실험, 유한차분법과비교 분석하였다. 그 결과 제안식의 값이 기존의 쐐기 이론과 1.03%, 현장실험과는 0.40~3.32%, 유한차분법과는 6.02%의 차이를 보였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1051-1060
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• 2010

In this study, the pressuremeter test (PMT) and the standard penetration test (SPT) were performed on the lateral pile loading tests site to evaluate the coefficient of subgrade reaction, which is used for load-deformation behavior analysis of laterally loaded piles by elastic subgrade reaction method. As a result, widely used empirical formulas of the coefficient of subgrade reaction by N values of SPT is evaluated conservatively lateral behavior of piles. While the method of directly used PMT results and evaluation method of the coefficient of subgrade reaction considering deformation moduli of soil and a pile diameter that is able to estimate very similar to actual load-deformation behavior of laterally loaded piles in deformation range of 0.5%-1.0% of a pile diameter.

• 한국지반공학회논문집
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• 제26권11호
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• pp.39-46
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• 2010

본 연구에서는 Strain Wedge 해석모델을 이용하여 수평하중이 작용하는 단독말뚝의 수평저항력 산출식을 제시하였고, 이를 모형실험, 현장 실험의 결과와 기존의 문헌에서 제시된 수평저항력 산정식과 비교 분석하였다. 그 결과 모형 실험의 시험 결과보다 조금 작게 나타났고, 현장 재하실험 결과와는 말뚝 두부의 변위가 작을 경우 상당히 잘 일치하고 있으나, 말뚝 두부의 변위가 증가할 수록 결과 값의 차가 조금씩 발생하였다. 그리고 기존의 산출식과 비교 검토한 결과 유한차분법과 잘 일치하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.708-712
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• 2008

Piles and pile foundations have been in common use since very early times. Usually function of piles is to carry load to a depth at which adequate support is available. Another important use of piles is to furnish lateral support and nowadays it is getting highlighted due to the wind load, lateral action of earthquake, and so on. After Broms (1964), many researchers have been suggested methods for estimating lateral capacity of pile. But each method assumes different earth pressure distribution and lateral earth pressure coefficient and it gives confusion to pile designers. Lateral earth pressure, essential in lateral capacity estimation, influenced by pile's behavior under lateral load. Prasad and Chari (1999) assumed the rotation point of pile and suggested an equation of ultimate lateral load capacity. In this study, we investigate the depth of rotation point in both homogeneous soil and multi layered soil, and compare to the estimation value by previous research. To model the pile set up in the sand, we use the chamber and small scale steel pile, and rain drop method. Test results show the rotation point is formed where the Prasad and Chari's estimation value, and they also show multi layered condition affects to location of rotation point to be scattered.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.744-747
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• 2008

In this study, to analyze the rotation point of piles, the laboratory lateral load test was performed. The lateral load bearing capacity is one of the important factor related with structure failure directly. Analyzing rotation point in different soil condition, relative density and stress condition, leads more accurate ultimate lateral bearing capacity. Also, reliability was analyzed about established 예측식 as applying to tapered pile. As a result, the established prediction was suitable to cylider pile, but not to tapered pile.

• 한국산학기술학회논문지
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• 제22권6호
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• pp.267-274
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• 2021

말뚝의 허용횡방향지지력을 결정하는 방법으로는 지반반력법과 극한횡방향지지력에 근거한 방법이 많이 쓰이고 있는데 설계시 지반반력법에 근거한 방법만을 적용하는 경우가 있다. 본 연구에서는 지반조건과 말뚝머리 구속조건 그리고 말뚝길이에 따른 말뚝의 허용지지력을 이들 두 가지 방법을 적용하여 구하고 상호 비교함으로써 해석에서 고려한 조건들이 말뚝의 허용횡방향지지력 결정법에 미치는 영향을 알아보고자 하였다. 연구결과에 따르면 말뚝머리 구속조건 및 말뚝길이에 상관없이 연약 점성토 지반에 설치된 말뚝의 경우 지반반력법에 의한 허용횡방향지지력이 설계를 지배함을 알 수 있었고 점성토의 비배수강도가 커짐에 따라 극한횡방향지지력을 통한 허용횡방향지지력이 설계를 지배함을 알 수 있다. 사질토 지반에 설치된 말뚝의 경우 느슨한 사질토지반에 설치된 말뚝머리 자유인 짧은말뚝의 경우를 제외하고 모든 경우에 있어 극한횡방향지지력을 통한 허용횡방향지지력이 설계를 지배함을 알 수 있다. 횡방향말뚝의 설게시 허용 횡방향변위량에 근거한 설계만으로 충분하다는 견해도 있지만 본 연구결과에 따르면 극한횡방향지지력에 근거한 허용횡방향지지력의 계산 또한 필요함을 알 수 있었다. 수평지반반력계수는 허용횡방향변위량 이내에서는 말뚝폭에 큰 영향을 받지 않음을 알 수 있었으며 실제 많이 쓰이는 말뚝폭의 범위인 20~90cm 인 경우 말뚝폭의 영향을 무시해도 될 것으로 생각된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1083-1086
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• 2008

In this study, Estimate solutions of ultimate lateral resistances for lateral loaded piles are proposed using cone penetration values, $q_c$ values, as CPT results. Cone penetration values, $q_c$ values measured on clean sand layers, are represented by factors for relative densities, axial stresses, and lateral stresses which are important on analysis of sandy soil layers. Also, these factors are same factors to consider existed estimations of ultimate lateral capacity. In this study, estimation of ultimate lateral capacity for lateral loaded piles using CPT results is proposed, and this estimation is verified by adequate analysis for effective reliability.