The reinforced retaining wall was introduced in the late 1980s and has been actively used since the 1990s in Korea 's expressway construction. At the beginning of the introduction, proper stiffeners and backfill materials were used and compaction management was thoroughly carried out, which was recognized as an economical and excellent workability method. However, the current understanding of reinforced earth retaining walls about 30 years old is a negative image such as inadequate reinforcement materials, backfill materials, insufficient compaction, and insufficient drainage system. In this way, the reinforced earth retaining walls that have been constructed in the midst of the negative perception are about 1,000 at the expressway site, and about 1000 will be completed in a few years and about 2,000 will be used. Most of the problems of reinforced earth retaining wall were found during maintenance, and countermeasures are suggested by tracing back to what problems were observed in the design and construction of the observed phenomena. The retaining walls to be installed in future maintenance should be minimized in designing and constructing to prevent problems. It is estimated that such a problem can be solved by changing the recognition. Therefore, in this study, damage cases of reinforcement retaining wall which is frequently occurred in the expressway of Korea were analyzed to derive the preventive maintenance method of reinforced earth retaining walls. Then, the problems and countermeasures were analyzed for each type of damage.

In Korea, the structure is mostly located on the upper part of the high embankment considering the geographical conditions at the time of expressway construction. Embankment was managed stepwise compaction according to height, but creep settlement of embankment itself may negatively affect superstructure. Reinforced earth retaining walls, which were recognized as flexible structures, were no exception to such geographical conditions. Especially, in the case of reinforced earth retaining wall located on abutment wing wall, damage due to differential settlement supported by pile, damage due to differential settlement and uneven settlement of reinforced earth retaining wall itself was frequently occurred. Therefore, in this study, the damage of reinforced earth retaining wall structure located on the high toe part was analyzed based on case. These data will be used as basic data for future maintenance.

본 연구는 공용 중 보강토옹벽에 발생하는 배부름현상을 보강하기 위한 방법을 제안하고 현장실험으로 보강방법의 신뢰성을 파악 하고자 하였다. 보강토옹벽의 배수시설을 미설치하여 강우에 의해 배부름현상이 유도되도록 하였으며, 시공 후 15일간 변위속도가 크게 발생한 후 점차적으로 감소하였다. 유도된 배부름현상의 변위는 미연방도로국(FHWA)의 시공 중 수평변위 기준을 적용하여 판단하였다. 배부름 현상을 보강하기 위해 보강토옹벽에 소일네일을 설치하고, 네일의 두부를 수평으로 서로 연결하여 보강토 옹벽의 블록들을 서로 지지할 수 있도록 하였다. 보강재들의 보호를 위해 숏크리트로 보강면을 마감하고 계측장치를 설치하였다. 배부름현상 보강방법의 신뢰성을 확인하기 위하여 변위의 진행을 검측한 결과 보강 후 수평변위는 거의 발생하지 않았으며, 보강방법의 신뢰성을 확인할 수 있었다.

In this study, field survey was carried out on reinforced earth retaining wall located on the expressway, and the damage type was classified and basic data about the state evaluation method was prepared

In this study, a case study on the field survey method and repair and reinforcement method of reinforced earth retaining wall damaged by salinity was carried out.

Reinforced earth retaining wall is being applied in many construction sites such as slopes, roads, retaining walls with the development of geosynthetic. The case caused a problem with the stability of the reinforced earth retaining walls often occurs because the construction is being conducted, ignoring the basic assumptions of the economical design. In this study, reinforced earth retaining wall damage cases were analyzed in order to derive the causes. The results of this study will be useful for future maintenance of reinforced earth retaining wall.

Highway construction to the reinforced earth retaining wall which is under constant traffic load there is a possibility of generating the displacement at the top. In this study, it was conducted determine how to repair reinforcement method through examination of cause and stability analysis when occurs the displacement of reinforced earth retaining wall.

프리캐스트 콘크리트제품은 빠른 시공, 노동력 절감, 높은 품질확보의 장점을 가지고 있어 옹벽구조물 분야에도 많이 적용하고 있다. 본 논문에서는 철도에 적용되는 프리캐스트 프리스트레스트로 제작된 옹벽의 동적안정성을 평가하기 위하여 이동열차하중 재하상태에서의 수치해석을 수행하였다. 해석에는 2차원 유한요소 해석이 적용되었다. 궤도에 작용하는 이동열차하중은 이동하중에 대한 충격력을 대표하는 조도성분의 위상각 자료와 열차자중을 대표하는 준정적 하중을 조합하여 사용하였다. 해석에는 노반과 옹벽구조물의 시간영역 변위, 응력, 가속도 결과값을 이용하여 옹벽의 동적안정성을 평가하였으며, 평가결과 충분한 적용성을 확인하였다.

Steel net gabion is eco-friendly retaining wall structure showing favorable ability to overcome construction and environmental restriction and also to resist corrosion, chemical attack and degradation. This paper is dealt with the applicability of gabion metal net as a substitution of existing strengthening material. Pull out test was carried out to verify the applicability of gabion metal net. According to results, the increase of surcharge loading and horizontal load resulted in a yield of metal net. The stress at the time of yield was in the range of elasticity. Accordingly, gabion metal net can be substituted for existing geogrid and there is a need for experiment and analysis of arrangement direction and durability of gabion steel net.

This paper presents eco-friendly planting method to overcome the problems of existing concrete retaining wall and gabion retaining wall, respectively, based on the examination on existing concrete and gabion retaining wall. Prior to doing this, proper design method was provided through pull out test. Planting method using gabion metal net and L shape green net retaining wall were compared and analyzed. According to this study, it is confirmed that reduction of construction period and economical profit in construction can be achieved by both manufacturing at the factory and self procurement at the job site as well as the use of metal net, which is applied as a substitution of existing strengthening material. For the effect of planting method, the use of L shape green net retaining wall shows superiority to environment-friendly gabion retaining wall in its ability to rootage and germination of the grass. The L shape green net retaining wall had excellent performance in helping rootage of grass and prevention of soil leakage, and even if raining period, remarkable damage of planting mat does not occur when planting mat is applied.

본 연구에서는 블록형 보강토 옹벽에 경사계, 침하계, 토압계, 수직 및 수형 변위계, 스트레인게이지 등의 각종 계측기를 매설하여 시공 중 및 시공 후의 보강토 옹벽의거동과 전면벽체에 작용하는 수평토압의 크기 및 분포형태. 그리드에 발현되는 변형 형태 및 인장력의 크기와 침하특성 등을 옹벽의 직선부와 곡선부로 구분하여 분석하였다.