• Title/Summary/Keyword: soil-structure interaction, tunnelling

Search Result 26, Processing Time 0.023 seconds

Damage Analysis of Nearby Structures with the Consideration of Tunnel Construction Conditions in Sandy and Clayey Ground (모래 및 점토지반에서 터널시공조건을 고려한 인접구조물의 손상도 분석)

  • Son, Moorak;Yun, Jongcheol
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.1C
    • /
    • pp.53-63
    • /
    • 2011
  • This paper investigates the effects of tunnelling-induced ground movements on nearby structures, considering soil-structure interactions of different ground (loose sand, dense sand, soft clay, stiff clay) and construction conditions (ground loss). The response of four-story block structures, which are subjected to tunnelling-induced ground movements, has been investigated in different ground and construction conditions (ground loss) using numerical analysis. The structures for numerical analysis has been modelled using Discrete Element Method (DEM) to have real cracks when the shear and tensile stress exceed the maximum shear and tensile strength. The response of four-story block structures has been investigated with a ground movement magnitude and compared in terms of ground and construction conditions (ground loss) considering the magnitude of deformations and cracks in structures. In addition, the damage levels, which are possibly induced in structures, has been provided in terms of ground and construction conditions (ground loss) using the state of strain damage estimation criterion (Son and Cording, 2005). The results of this study will provide a background for better understandings for controlling and minimizing building damage on nearby structures due to tunnelling-induced ground movements.

The Seismic Behavior of Corrugated Steel Plate Lining in Cut-and-Cover Tunnel (개착식 터널에서 파형강판 라이닝의 동적 거동 특성)

  • Kim Jung-Ho;Kim Nag-Young;Lee Yong-Jun;Lee Seung-Ho;Chung Hyung-Sik
    • 한국터널공학회:학술대회논문집
    • /
    • 2005.04a
    • /
    • pp.233-247
    • /
    • 2005
  • Most tunnel lining material which has been used in the domestic is a concrete. But many problems as the construction period, the cost, and the crack occurrence for the design, construction, and management were happened in the concrete lining. For this reason, many research institutes like the Korea Highway Corporation recognize the necessity of an alternate material development and grow on the interest for that. So in this study, the seismic behaviour characteristics for the application of the Corrugated Steel Plate Lining in cut-and-cover tunnel are evaluated as several conditions for the backfill height, the cutting slope, and the relative density of backfill soil are changed. The compressive stress which is calculated in the Corrugated Steel Plate Lining by the seismic load is decreased as the backfill height increases and the cut slope grows gentle. Also, the moment shows the tendency of decrease according to the increase of the backfill height. But in the case of the relative density of the backfill soil is small, the moment increases according to the increase of the backfill height and affects the dynamic behaviour characteristic. So it is considered that the relative density of the backfill soil is also the important point. As the result in analyzing the seismic response characteristics of the reinforcement spacing of the Corrugated Steel Plate, the variation in the compressive force is hardly happened, but the moment and the shear force increase on the reinforcement spacing being narrow.

  • PDF

Effects of interface stiffness on dynamic behavior of connections between vertical shafts and tunnels under earthquake (지진 시 공동구용 수직구-터널 접속부 거동에 대한 경계면 강성 계수의 영향)

  • Kim, Jung-Tae;Hong, Eun-Soo;Kang, Seok-Jun;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.6
    • /
    • pp.861-874
    • /
    • 2019
  • A great interest in the seismic performance evaluation of small size tunnel structures such as utility tunnel has been taken since recent earthquakes at Pohang and Gyeongju in Korea. In this study, the three-dimensional dynamic analyses of vertical shaft and horizontal tunnel under seismic load were carried out using FLAC3D. Especially, parametric analyses was performed to investigate the effects of interfacial stiffness on interfacial behavior between soil and structure. The parametric analysis showed that the interfacial stiffness scarcely gave an effect on the global dynamic behavior of the structure, while had a significant effect on the local displacement behavior of the connections. The magnitude of the interfacial stiffness was inversely proportional to the displacement, while the magnitude of interface stiffness was proportional to the normal and shear stresses. The results of this study suggest the limitations of the existing empirical equations for interfacial stiffness and emphasize the need to develop new interfacial stiffness models.

Damage Assessment of Adjacent Structures due to Tunnel Excavation in Urban Areas (II) - Focused on the Variations of Building Stiffness Ratio - (도심지 터널 굴착에 따른 인접구조물의 손상평가에 관한 연구 (II) - 지상 건물의 강성비 변화를 중심으로 -)

  • 김창용;배규진;문현구;박치현;오명렬
    • Journal of the Korean Geotechnical Society
    • /
    • v.15 no.5
    • /
    • pp.81-98
    • /
    • 1999
  • The influence of tunnelling on buildings has become an important issue in urban areas. The problem is an interactive one: not only do tunnelling settlements affect existing structures, but existing structures affect tunnel-induced soil movements. In order to examine the constraint of surface settlement and the degradation of building damage parameters, 3-dimensional elasto-plastic finite element analyses are peformed. Also, in this paper, the results of the parametric studies for the variations of the damage parameters due to the ground movements are presented by utilizing 2-dimensional elasto-plastic finite element models, totally 162 models. The width of a structure, its bending and axial stiffness, its position relative to the tunnel and the depth of tunnel are considered. The interaction is shown by reference to commonly-used building damage parameters, namely angular distortion, deflection ratio, maximum building settlements, maximum differential settlements and horizontal strain. By introducing relative stiffness parameters which combine the bending and axial stiffness of the structure with its width and stiffness of soil, design curves are established. These give a guide as to the likely modification of the greenfield settlement trough caused by a surface structure. They can be used to give initial estimates of likely building damage.

  • PDF

A comparative study on dynamic behavior of high-rise building and low-rise building considering SSI analysis (SSI 해석을 고려한 초고층 및 저층 건물 동적거동 비교 연구)

  • You, Kwang-Ho;Kim, Seung-Jin
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.20 no.6
    • /
    • pp.973-987
    • /
    • 2018
  • Most of the previous seismic analyses have been carried out by separating the ground and structures, and there is a lack of comparative study on the dynamic behavior of high-rise and low-rise buildings. Therefore, in this study, the sensitivity analysis was performed with selected parameters by using a finite element analysis program in order to grasp the dynamic behavior of high-rise and low-rise buildings. As a result, it was turned out that the horizontal displacement, the interstory drift ratio, and the bending stress of a high-rise building were more affected by a long seismic wave than a low-rise buildings. Also, the weak parts of a high-rise and low-rise building were more affected by type of seismic wave than the ground conditions. Therefore, it is inferred that it will be helpful for seismic designs to consider the influence of ground conditions and seismic wave type on buildings.

Analysis on the characteristics of the earth pressure distribution induced by the integrated steel pipe-roof construction (일체형 강관 파이프루프 시공에 따른 주변 지반의 토압 분포 특성 분석)

  • Sim, Youngjong;Jin, Kyu-Nam;Song, Ki-Il
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.15 no.5
    • /
    • pp.455-468
    • /
    • 2013
  • In recent, various types of steel pipe-roof methods, which is reinforced by mortar after propulsion of steel pipe into the ground, have been used for the construction of trenchless underpass. Integrated steel pipe-roof has flexural stiffness and can resist against overburden load and reduce the stress acting on the concrete underpass structures. Due to arching effect, vertical and horizontal stress distribution around the steel pipe-roof is changing. In this study, therefore, the characteristic of stress distribution around the underpass induced by the construction of integrated steel pipe-roof is investigated by using numerical method. To examine the soil-structure interaction, interface element is introduced. Results show that vertical stress acting on the concrete structure placing inside the steel pipe-roof is significantly reduced due to arching effect and flexural stiffness of integrated steel pipe-roof. Design load can be reduced and effective design of underpass will be available if the earth pressure reduction due to arching effect is considered in the design stage.