• 한국지반환경공학회 논문집
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• 제16권2호
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• pp.33-43
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• 2015

This paper investigated the magnitude and distribution of earth pressure on the support system in jointed rock mass by considering different earth pressure coefficients, rock types and joint inclination angles. The study mainly focused on the effect of the earth pressure coefficients on the earth pressure. Based on a physical model test (Son & Park, 2014), extended studies were conducted considering rock-structure interactions based on the discrete element method, which can consider the joints characteristics of rock mass. The results showed that the earth pressure was highly influenced by the earth pressure coefficients as well as the rock type and joint inclination angles. The effects of the earth pressure coefficients increased when the rock suffered more weathering and has no joint slide. The test results were also compared with Peck's earth pressure for soil ground, and clearly showed that the earth pressure in jointed rock mass can be greatly different from that in soil ground. This study indicated the earth pressure coefficients considering the rock types and joint inclination angles are important parameters influencing the magnitude and distribution of earth pressure, which should be considered when designing the support systems in jointed rock mass.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1994년도 가을 학술발표회 논문집
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• pp.129-138
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• 1994

It is well recognized that accurate analysis of lateral earth pressure is very signficant factor which determines the design amount of braced cut walls and braced systems. Many researchers, Peck, Terzaghi-Peck and so on, make a study about lateral earth pressure to act on the flexible walls. But these studies trouble accurate to multy layered systems like inland areas in Korea. This study is compared with the field messurement data to estimate the earth pressure distributions in multy layered areas and the empirical earth pressure distributions. The conclusions are as follows : At final excavation depth, the lateral earth pressure which messured by field instrument is smaller than the empirical earth pressure. (About 1.85~5.32 times). In the case of considering the soft rock layer to the final excavation depth, the messured earth pressure is safe to be compared with empirical earth pressure. The messured earth pressure distributions are like that the upper soil layer is small the middle soil layer is large, the rock mass layer is very small.

• 한국지반신소재학회논문집
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• 제14권2호
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• pp.23-33
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• 2015

개착식 터널공법으로 시공된 지하철 건설현장을 대상으로 각종 계측시스템을 적용하여 지하 박스구조물에 작용하는 토압을 측정하였다. 이를 토대로 기존 이론식으로 산정된 측방토압과 현장에서 계측된 실측토압을 비교 검토하고, 실제 지하구조물에 작용하는 토압분포를 조사하였다. 조사결과에 의하면 지하 박스구조물에 작용하는 연직토압은 주로 성토고에 큰 영향을 받고 있으며, 측방토압은 흙막이구조물(버팀보, 흙막이벽)의 존치여부에 큰 영향을 받는 것으로 나타났다. 현장에서 측정된 지하 박스구조물 상단에 작용하는 연직토압은 Bierbaumer의 이론토압에 가장 근사하게 나타나고 있으며, 측방토압은 정지토압보다 주동토압에 가깝게 작용하고 있다. 그리고, 토압계수는 토사층의 경우 평균 0.35정도로 나타났으며 연암층의 경우 평균 0.21정도로 토사층에서 크게 나타나고 있다. 따라서, 지하 박스구조물이 토사층에 설치되는 경우, 지하 박스구조물에 작용하는 측방토압은 정지토압보다는 주동토압과 정지토압의 평균치를, 암반층에 설치되는 경우에는 주동토압을 사용하는 것이 보다 합리적이라고 판단된다.

• 한국지반공학회논문집
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• 제39권7호
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• pp.5-15
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• 2023

수평방향의 토압에 저항하는 흙막이 구조물(옹벽, 가시설 등) 설계에서 수동토압(Passive earth pressure) 산정은 중요한 요소이다. 토압이론에서 주동토압과 수동토압은 벽체 변위가 충분히 발생하여 한계변위에 도달한 한계상태에서의 토압이다. 흙막이 구조물설계에서 수동토압은 저항력으로 고려되는데, 이때, 수동토압이 발생하는 한계변위는 주동토압이 발생하는 한계변위의 10배 이상으로 이 변위를 수동토압산정에 적용하는 것은 비합리적이다. 그러므로 한계변위의 수동토압(Passive earth pressure)이 아닌 임의 크기의 수평변위에서 발생되는 임의 수동토압을 발현수동측토압(Mobilized passive earth pressure)으로 정의하고 흙막이 구조물의 안정성 검토에 발현수동측토압을 적용하는 것이 현실적으로 필요하다고 판단하였다. 본 연구에서는 모래지반에 대하여 문헌조사를 통해 흙막이 구조물의 안정성 확보가 가능한 허용수평변위를 0.002H(H:굴착깊이)로 제안하였으며, 임의수평변위에서 발생되는 발현수동측토압을 산정할 수 있는 반경험식을 사용하였다. 그리고 사질토 지반에서 구해진 발현수동측토압 자료를 바탕으로 실무에서 간단하게 적용할 수 있도록 벽체의 거동양상에 따른 Rankine의 수동토압에 적용 가능한 감소계수를 제안하였다.

• Geomechanics and Engineering
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• 제11권6호
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• pp.879-896
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• 2016

A new earth pressure equation considering the arching effect in $c-{\phi}$ soils was proposed for the accurate calculation of earth pressure on circular vertical shafts. The arching effect and the subsequent load recovery phenomenon occurring due to multi-step excavation were quantitatively investigated through laboratory tests. The new earth pressure equation was verified by comparing the test results with the earth pressures predicted by new equation in various soil conditions. Resulting from testing by using multi-step excavation, the arching effect and load recovery were clearly observed. The test results in $c-{\phi}$ soil showed that even a small amount of cohesion can cause the earth pressure to decrease significantly. Therefore, predicting earth pressure without considering such cohesion can lead to overestimation of earth pressure. The test results in various ground conditions demonstrated that the newly proposed equation, which enables consideration of cohesion as appropriate, is the most reliable equation for predicting earth pressure in both ${\phi}$ soil and $c-{\phi}$ soil. The comparison of the theoretical equations with the field data measured on a real construction site also highlighted the best-fitness of the theoretical equation in predicting earth pressure.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.387-394
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• 2001

An apparent earth pressure envelope for anchored walls proposed by FHWA was compared with Terzaghi & Peck's earth pressure envelope. The anchor design load, the maximum bending moment and the penetration depth were calculated by a simple beam analogy method for each type of envelope.

• 한국지반환경공학회 논문집
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• 제19권2호
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• pp.13-21
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• 2018

The magnitude and distribution of earth pressure on the excavation wall in jointed rock mass were examined by considering different wall permeability conditions as well as rock types and joint inclination angles. The study was numerically extended based on a physical model test (Son & Park, 2014), considering rock-structure interactions with the discrete element method, which can consider various characteristics of rock joints. This study focused on the effect of the permeability condition of excavation wall on the earth pressure in jointed rock masses under a groundwater condition, which is important but has not been studied previously. The study results showed that the earth pressure was highly influenced by wall permeability as well as rock type and joint condition. Earth pressure resulted from the study was also compared with Peck's earth pressure in soil ground, and the comparison clearly showed that the earth pressure in jointed rock mass can be greatly different from that in soil ground.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.489-496
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• 1999

The safety of a structure can be improved by applying the three dimensional passive earth pressure. Because the three dimensional passive earth pressure is much larger than the two dimensional passive earth pressure and it is determined by the size(width B and height H) and the wall frictional angle of the resistant wall. Therefore, the three dimensional passive resistance behavior was studied through the model tests in sandy ground, where the size of the resistant wall and the wall frictional angle were varied. The results show that three dimensional passive earth pressure is 1.1∼3.4 times larger than that of the two dimensional value depending on the wall size and the wall friction.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1073-1080
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• 2010

In this paper, the centrifuge model tests were conducted for the sake of measuring three dimensional arching earth pressure while two step excavation of the vertical shaft. The results of the centrifuge model tests were compared to newly suggested arching earth pressure equation proposed by Kim et al(2009) and two dimension earth pressure(Rankine). As the results, Measured arching earth pressure revealed about 35 percentages of two dimension earth pressure(Rankine) and almost same as that of newly suggested arching earth pressure equation.

• Geomechanics and Engineering
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• 제8권4호
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• pp.523-540
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• 2015

Based on limit equilibrium principles, this study presents a theoretical derivation of a new analytical formulation for estimating magnitude and lateral earth pressure distribution on a retaining wall subjected to seismic loads. The proposed solution accounts for failure wedge inclination, unit weight and friction angle of backfill soil, wall roughness, and horizontal and vertical seismic ground accelerations. The current analysis predicts a nonlinear lateral earth pressure variation along the wall with and without seismic loads. A parametric study is conducted to examine the influence of various parameters on lateral earth pressure distribution. Findings reveal that lateral earth pressure increases with the increase of horizontal ground acceleration while it decreases with the increase of vertical ground acceleration. Compared to classical theory, the position of resultant lateral earth force is located at a higher distance from wall base which in turn has a direct impact on wall stability and economy. A numerical example is presented to illustrate the computations of lateral earth pressure distribution based on the suggested analytical method.