• 제목/요약/키워드: Lateral displacement

검색결과 1,272건 처리시간 0.026초

교량구조물의 측방이동 측정방법에 관한 연구 (The Measurement Method of Lateral Displacement in Bridge Abutment.)

  • 장용채
    • 한국항만학회지
    • /
    • 제14권1호
    • /
    • pp.115-124
    • /
    • 2000
  • This study is a suggest a measurement method of lateral displacement, which can be used to judge the stability of bridge abutment on soil undergoing lateral movement. The abutment of bridge on soft foundation makes lateral movement due to the settlement of back fill and lateral flow. To measure the displacement of such a abutment, there are a lot of indirect method for measurement such as survey of leveling or inclinometer gauge around the abutment. But all of them are not sufficient to confirm the ground behavior and measure the exact lateral behavior of structure. As making the structure and pile cooperatively by measuring the movement of lateral displacement, for measuring the abutment displacement precisely by using the inclinometer. In this work, we try to suggest efficient measuring method of abutment displacement and its application.

  • PDF

경사계를 이용한 교대변위 계측에 관한 연구 (The Measurement of Lateral Displacement of Abutment Using a Inclinometer)

    • 한국항해항만학회:학술대회논문집
    • /
    • 한국항해항만학회 2000년도 춘계학술대회논문집
    • /
    • pp.82-90
    • /
    • 2000
  • The abutment of bridge on soft foundation makes lateral movement due to the settlement of back fill and lateral flow. To measure the displacement of such a abutment, there are a lot of indirect method for measurement such as survey of leveling or inclinometer gauge around the abutment. But all of them are not sufficient to confirm the ground behavior and measure the exact lateral behavior of structure. As making the structure and pile cooperatively by measuring the movement of lateral displacement, for measuring the abutment displacement precisely by using the incliinometer. In this work, we try to suggest efficient measuring method of abutment displacement and its application.

  • PDF

연약지반상에 축조된 호안의 측방유동에 따른 안벽말뚝의 변위 (Displacement of Quaywall Pile by Lateral Movement of Revetment on Soft Ground)

  • 신은철;류인기;김종인
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.932-939
    • /
    • 2005
  • Recently, the lateral displacement of the passive piles which installed under the revetment on soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of the ground when the revetment loading is exceeded a certain limit. The lateral displacement of ground causes an excessive deformation of under structure itself and develops lateral earth pressure against the pile foundation as well. Especially passive piles subjected to lateral earth pressures are likely to have excessive horizontal displacement and large bending moment, which induces structural failure of pile foundation and harmful effects on superstructure. The subject of study is to investigate the later displacement of pile foundation during the construction of container terminal at the south port of Incheon. Actual field measurement data and finite element method(FEM) by AFFIMEX Ver 3.4 were used to analyze the displacement of pile and the vertical settlement of soft ground. This analysis was carried out at each sequence of construction work.

  • PDF

Extending torsional balance concept for one and two way asymmetric structures with viscous dampers

  • Amir Shahmohammadian;Mohammad Reza Mansoori;Mir Hamid Hosseini;Negar Lotfabadi Bidgoli
    • Earthquakes and Structures
    • /
    • 제25권6호
    • /
    • pp.417-427
    • /
    • 2023
  • If the center of mass and center of stiffness or strength of a structure plan do not coincide, the structure is considered asymmetric. During an earthquake, in addition to lateral vibration, the structure experiences torsional vibration as well. Lateraltorsional coupling in asymmetric structures in the plan will increase lateral displacement at the ends of the structure plan and, as a result, uneven deformation demand in seismically resistant frames. The demand for displacement in resistant frames depends on the magnitude of transitional displacement to rotational displacement in the plan and the correlation between these two. With regard to the inability to eliminate the asymmetrical condition due to various reasons, such as architectural issues, this study has attempted to use supplemental viscous dampers to decrease the correlation between lateral and torsional acceleration or displacement in the plan. This results in an almost even demand for lateral deformation and acceleration of seismic resistant frames. On this basis, using the concept of Torsional Balance, adequate distribution of viscous dampers for the decrease of this correlation was determined by transferring the "Empirical Center of Balance" (ECB) to the geometrical center of the structure plan and thus obtaining an equal mean square value of displacement and acceleration of the plan edges. This study analyzed stiff and flexible torsional structures with one-way and two-way mass asymmetry in the Opensees software. By implementing the Particle Swarm Optimization (PSO) algorithm, the optimum formation of dampers for controlling lateral displacement and acceleration is determined. The results indicate that with the appropriate distribution of viscous dampers, not only does the lateral displacement and acceleration of structure edges decrease but the lateral displacement or acceleration of the structure edges also become equal. It is also observed that the optimized center of viscous dampers for control of displacement and acceleration of structure depends on the amount of mass eccentricity, the ratio of uncoupled torsional-to-lateral frequency, and the amount of supplemental damping ratio. Accordingly, distributions of viscous dampers in the structure plan are presented to control the structure's torsion based on the parameters mentioned.

A novel approach for predicting lateral displacement caused by pile installation

  • Li, Chao;Zou, Jin-feng;Li, Lin
    • Geomechanics and Engineering
    • /
    • 제20권2호
    • /
    • pp.147-154
    • /
    • 2020
  • A novel approach for predicting lateral displacement caused by pile installation in anisotropic clay is presented, on the basis of the cylindrical and spherical cavities expansion theory. The K0-based modified Cam-clay (K0-MCC) model is adopted for the K0-consolidated clay and the process of pile installation is taken as the cavity expansion problem in undrained condition. The radial displacement of plastic region is obtained by combining the cavity wall boundary and the elastic-plastic (EP) boundary conditions. The predicted equations of lateral displacement during single pile and multi-pile installation are proposed, and the hydraulic fracture problem in the vicinity of the pile tip is investigated. The comparison between the lateral displacement obtained from the presented approach and the measured data from Chai et al. (2005) is carried out and shows a good agreement. It is suggested that the presented approach is a useful tool for the design of soft subsoil improvement resulting from the pile installation.

철도차량의 횡 변위에 대한 연구 (Study for The Lateral Displacement of Railway Vehicle)

  • 양희주;오택열
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 추계학술대회 논문집
    • /
    • pp.535-538
    • /
    • 1997
  • Studied in this paper was the lateral displacement of railway vehicle using the multi-body dynamic simulation program (VAMPIRE) and the BASS 501. The lateral displacement of railway vehicle is occurred by thc clearance between wheel flange and rail, the track irregularity, the property of each suspension of vehicle and the cant etc. The results of analysis shown that Vehicle is not interfere with subway platform in any conditions namely the tare and full load condition, the wheel. wear condition and the stationary and running of vehicle.

  • PDF

철도차량 2 차 횡댐퍼 및 궤도특성에 따른 차체 횡변위 변화 연구 (Carbody Lateral Displacement of Railway Vehicle According to 2nd Lateral Damper and Track Characteristics)

  • 유원희;신유정;허현무;박준혁
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2012년도 춘계학술대회 논문집
    • /
    • pp.722-728
    • /
    • 2012
  • In railway vehicle, riding comfort depends mainly on the secondary lateral damper and track condition. When the damping force of lateral damper becomes abnormal condition or the track condition is worse, the running stability and ride comfort of the railway vehicles go down. In addition, the lateral motion of carbody is increased. Therefore, the lateral motion of carbody is reviewed carefully by considering lateral damping force and track condition of the railway line in design stage. In this study, the lateral displacement of carbody was studied in accordance with lateral damping force and track condition. The target vehicle is EMU for subway line.

  • PDF

모래지반에서 횡방향 반복하중을 받는 말뚝의 영구수평변위 평가 (Evaluation of Permanent Lateral Displacement of a Cyclic Laterally Loaded Pile in Sandy Soil)

  • 백성하;김준영;이승환;정충기
    • 한국지반공학회논문집
    • /
    • 제33권2호
    • /
    • pp.17-26
    • /
    • 2017
  • 해상구조물, 송전탑 등을 지지하는 말뚝기초는 바람, 조류, 파랑 등의 영향으로 횡방향 반복하중을 지배적으로 받으며, 이는 말뚝 주변 지반에 영구수평변위를 발생시켜 구조물의 안정성 및 기능성을 저해한다. 본 연구에서는 횡방향 반복하중에 의해 발생하는 말뚝의 영구수평변위를 평가하기 위하여, 서로 다른 세 가지 상대밀도(40%, 70%, 90%)로 조성된 건조 및 포화 모래지반에서 모형말뚝시험을 수행하였다. 모형시험 결과, 모든 시험조건에서 말뚝에 재하 된 횡방향 반복하중은 말뚝 주변 지반에 영구수평변위를 발생시켰다. 누적된 영구수평변위의 크기는 말뚝에 재하되는 횡방향 반복하중의 크기 및 재하횟수가 증가함에 따라 증가하였지만, 1회 재하로 인하여 발생되는 영구수평변위의 증가량은 점차 감소하였다. 또한, 말뚝에 발생하는 영구수평변위는 지반의 상대밀도가 클수록 작게 발생하고, 지반이 포화되면 크게 발생되는 것으로 평가되었다. 추가적으로, 누적 영구수평변위를 최초 재하 시 발생한 영구수평변위로 정규화한 영구수평변위를 평가하였으며, 이를 모래지반의 상대밀도, 횡방향 반복하중의 재하횟수에 관한 식으로 나타내었다.

Experimental investigation of lateral displacement of PVD-improved deposit

  • Chai, Jin-Chun;Xu, Fang
    • Geomechanics and Engineering
    • /
    • 제9권5호
    • /
    • pp.585-599
    • /
    • 2015
  • Laboratory model tests were conducted to investigate the effect of surcharge loading rate on the magnitude of lateral displacement of prefabricated vertical drains (PVDs) improved deposit. The test results indicate that under the condition that the system had sufficient factor of safety (FS) ($FS{\geq}1.2$), for the similar model ground under the same total applied surcharge load, the lateral displacement increases with the increase of loading rate. The test results have been used to check the validity of a previously proposed method for predicting the maximum lateral displacement, and it shows that the data points are around the middle line of the predicted range, which supports the usefulness of the proposed method. The basic idea of the prediction method is an empirical relationship between the normalized lateral displacement (NLD) and a ration of load to the undrained shear strength of the deposit (RLS). The model test results offer some modifications of the NLD-RLS relationship: (1) instead of a bilinear relationship, NLD-RLS relationship may be entirely nonlinear; (2) the upper bound value of RLS for the proposed method can be used may be limited to 2.1 instead of the originally proposed value of 3.0.

배전용 콘크리트전주 기초지반의 횡방향변위 분석 (Lateral Displacement Analysis of Concrete Electric Pole Foundation Grounds)

  • 안태봉
    • 조명전기설비학회논문지
    • /
    • 제23권5호
    • /
    • pp.42-49
    • /
    • 2009
  • 배전용 콘크리트 전주에 작용하는 힘들이 지반의 변위에 미치는 영향을 유한요소법을 이용하여 분석하였다. 지반의 종류, 풍하중, 근가의 위치, 매입길이, 경간의 길이를 변화시키며 단전주와 겹전주의 경우에 지반의 변위를 분석하였다. 근가의 위치는 매입길이의 1/4지점에서 변위가 최소로 나타났다. 지반의 종류는 지반의 강성이 클수록 변위가 작아서 연약한 점토나 느슨한 모래지반 또는 실트 지반은 변위가 크다. 겹전주는 굴착면적이 커서 변위가 다소 큰 것으로 판단되며 시공시에는 콘크리트보강이 필요하다. 지표면에 가까울수록 횡방향 변위는 매입길이비가 작은 전주가 더 크게 나타났다. 횡방향 변위를 줄이기 위해서는 매입길이를 크게 하는 것이 좋다. 경간길이는 횡방향 변위에 영향이 별로 없는 것으로 나타났다.