• Geomechanics and Engineering
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• 제17권5호
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• pp.413-420
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• 2019

The changes in earth pressure and ground settlement due to underground excavation near an existing retaining wall were studied experimentally according to the separation distance between the underground excavation and the retaining wall. In addition, this study attempted to experimentally prove that the arching phenomenon occurred during the construction of the underground space. A model tank having 120 cm in length, 160 cm in height, and 40 cm in width was manufactured to simulate underground excavation through the use of five separated base wall bodies. The variation of earth pressure on the retaining wall was measured according to the underground excavation phase through the use of 10 separated right wall bodies. The results showed that the earth pressure on the retaining wall was changed by the lowering of the first base bottom wall; however, the earth pressure was not changed significantly by the lowering of the third base bottom wall, since the third base wall had sufficient separation distance from the retaining wall. Lowering of the first base wall induced a decrease in the earth pressure in the lower part of the retaining wall; in contrast, lowering of the first base wall induced an increase in the earth pressure in the middle part of the retaining wall, proving the arching effect experimentally. It is necessary to consider the changes in earth pressure on the retaining wall in designing earth retaining structures for sections where the arching effect occurs.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.158-167
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• 2008

Reinforced earth wall system has been popularized since its introduction to Korean civil engineering society in early 1980's. Nowadays, the increased use of reinforced earth wall for the purpose of obtaining more land brings several additional demands such as environmental-friendly, better stable and constructible, and economical system. This paper introduces some recently developed reinforced earth wall systems with consideration of the current demands.

• 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.

• 한국안전학회지
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• 제24권5호
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• pp.57-62
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• 2009

In this study, the numerical analyses regarding the distance between the guardrail and the reinforced earth wall as parameter were performed to determine the safe distance of guardrail installed on reinforced earth wall from the reinforced earth wall. The analyses were fulfilled by increasing the distance between the guardrail and reinforced earth wall from 150mm to 750mm. The computer program used in this research is LS-DYNA, which is very' popular in analysis of vehicle collision. Ford single unit truck in NCAC was employed as the model of vehicle and the velocity of vehicle collision was 80km/hr. As a results of analyses, the safety of guardrail was secured regardless of the distance between the guardrail and block of reinforced earth wall. However, to secure the safety of block of reinforced earth wall the distance between the guardrail and block of reinforced earth wall should be over 600mm.

• 한국태양에너지학회 논문집
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• 제24권2호
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• pp.63-71
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• 2004

Energy and environmental concerns accelerate the interest in passive solar heating in buildings, which utilizes solar energy through natural heat transfer. Moreover concerns about environmentally friendly materials were also increased. This study aims to evaluate the thermal performance of a Trombe wall built with earth. The thermal performance of the Trombe walls was analysed with results from computer simulations with TRNSYS 15. The thermal performance of the three types of Trombe wall was compared.: concrete. rammed earth. adobe. It was found that Trombe wall with the thermal storage wall of earth performed better than that of concrete. Rammed earth and adobe Trombe walls gained 4.7% and 12.8% more solar energy. respectively. than the concrete Trombe wall. In earth-applied Trombe walls. the energy gain by natural convection released from the airspace was about 75% of the total solar gains. that took 15% more than concrete Trombe wall. Rammed earth and adobe Trombe walls seem to be more suitable for buildings that use mostly in daytime. such as school, office and so on.

• 한국지반환경공학회 논문집
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• 제11권6호
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• pp.39-46
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• 2010

기존의 보강토 옹벽의 연구는 보강토 옹벽의 내적 외적파괴에 중점이 되어 연구가 이루어져 왔고 외부 충격에 관한 연구는 지진에 관한 것이 전부인 것이 현실이다. 도로의 발달로 인해서 도로 주변의 보강토 옹벽에 차량의 충돌 같은 외부 충격을 받는 경우가 늘어나고 있다. 그래서 본 연구에서는 신뢰도를 인정받고 있는 범용 유한요소 프로그램인 LS-DYNA를 사용하여 도로 주변 보강토 옹벽을 모델링하였고, NCAC에서 제공하는 8톤 중량의 Ford single unit truck을 이용하여 차량속도에 따른 보강토 옹벽의 거동 양상을 분석하였다. 그리고 향후 도로 주변에 시공되어지는 보강토 옹벽의 충돌에 관한 안정성을 확보하기 위해서 하단에 중력식 옹벽을 적용하였고 또한 높이를(0.5m, 1.0m, 1.5m) 변화시켜가면서 수치해석을 수행하여 보강토 옹벽의 거동을 분석하고 보강토 옹벽의 안정성을 확인 하였다.

• 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.

• 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 2005년도 지반공학 공동 학술발표회
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• pp.84-91
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• 2005

In case of soil nailing system, there have been many attempts to expand into slope and temporary earth retaining system stabilization method since the first ground excavation earth retaining system construction in 1993. Recently, jointing wall, underground wall of buildings and excavation earth retaining wall, construction were increasingly applied for effective utilization of the limited underground space and land application maximized. However, the application of joining wall into retaining wall or building by temporary soil nailing system and design of permanent wall were performed by using Rankine earth pressure theory without considering the distribution of earth pressure in the soil nailing. In this study was performed to introduce the design case by 'Two-Body Translation mechanism (TBTM)' to be able to consider distribution of earth pressure in the soil nailing when designing the permanent jointing wall using soil nailing system for effective utilization of ground space. Also, this study attempts to evaluate the earth pressure change, decreasing effect of wall displacement and increasing effect of stability when advanced soil nailing system is constructed using $FLAC^{2D}$ ${\nu}er.$ 3.30 program and 'Two-Body Translation mechanism'.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.87-94
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• 2000

This paper concerns the distribution of earth pressures on a cantilever wall with unattached reinforcements in the backfill. This type of walls is different from the existing reinforced earth walls in that unattached reinforcements are placed in the backfill of rigid retaining wall such as gravity wall and cantilever wall, instead of connecting reinforcements to the wall segments. Two large-scale prototype tests have been carried out with a 4m high cantilever wall; one with unreinforced backfill, the other with unattached strips in the backfill. The reinforcing effect of unattached strips are discussed based on the earth pressure distribution measured in two large-scale prototype tests. Also, the comparison between measured and predicted earth pressure on a wall with unattached strips are discussed herein to confirm the validity of analytical prediction.