• Title/Summary/Keyword: lateral damage

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Comparison of Displacement of the Braced Retaining Wall by Developed Elasto-Plastic Analysis (개선된 탄소성 해석을 이용한 버팀지지 흙막이벽의 거동비교)

  • Shin, Jin-Whan;Kim, Dong-Shin
    • Journal of the Korean Society of Safety
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    • v.19 no.2
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    • pp.112-118
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    • 2004
  • Recently, when being constructed the large structures, the deep excavations have performed to utilize the underground space. As the ground excavation is deeper, the damage of the adjacent structure and the ground is frequently occurred. the Analysis of the retaining structures is necessary to safety of the excavation works. There are many methods such as elasto-plastic theory, FEM, and FDM to analyze the displacement of the retaining structure. In this thesis, GEBA-1 program by the Nakamura-Nakajawa elasto-plastic method was developed. The lateral displacement of the wall was analyzed by the developed program GEBA-1, SUNEX, and EXCAD, and compared with the measured displacement bye the Inclinometer. The monitored fields were three excavation work site in S-I, S-II, and S-III area. Excavation method of each site is braced retaining wall using H-pile. Excavation depth is 14m, 14m, and 8.2m.

High Lumbar Disc Herniation Treated with A Modified Posterolateral Approach - Case Report - (상위 요추간판 탈출증에 대한 후측방 접근술 - 증 례 보 고 -)

  • Hwang, Hyung Sik
    • Journal of Korean Neurosurgical Society
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    • v.30 no.1
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    • pp.114-117
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    • 2001
  • Generally, the posterolateral approach had been recommended in case of extraforaminal disc herniation or lateral stenosis but it has been speculated that this procedure may be feasible to posterolateral disc herniation at the high lumbar levels of the L1-L2 interspace. Topographically, a posterolateral approach should be able to access anteromedial side of the spinal canal without the risk of the bony instability and damage to the neural structures. During the past one year period, three patients with high lumbar discs at the L1-L2 level were treated by the modified posterolateral approach. This article describeds the details of this approach with pertinent literature review.

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Modelling seismically repaired and retrofitted reinforced concrete shear walls

  • Cortes-Puentes, W. Leonardo;Palermo, Dan
    • Computers and Concrete
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    • v.8 no.5
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    • pp.541-561
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    • 2011
  • The Finite Element Method (FEM) was employed to demonstrate that accurate simulations of seismically repaired and retrofitted reinforced concrete shear walls can be achieved provided a good analysis program with comprehensive models for material and structural behaviour is used. Furthermore, the analysis tool should have the capability to retain residual damage experienced by the original structure and carry it forward in the repaired and retrofitted structure. The focus herein is to provide quick, simple, but reliable modelling procedures for repair and retrofitting strategies such as concrete replacement, addition of diagonal reinforcing bars, bolting of external steel plates, and bonding of external steel plates and fibre reinforced polymer sheets, thus illustrating versatility in the modelling. Slender, squat, and slender-squat shear walls were investigated. The modelling utilized simple rectangular membrane elements for the concrete, truss bar elements for the steel and FRP retrofitting materials, and bond-link elements for the bonding interface between steel or FRP to concrete. The analyses satisfactorily simulated seismic behaviour, including lateral load capacity, displacement capacity, energy dissipation, hysteretic response, and failure mode.

A CASE REPORT OF SURGICAL CORRECTION OF POSTTRAUMATIC LAGOPHTHALMOS (외상에 의한 마비성 토안(兎眼)의 외과적 치험례)

  • Lee, Tae-Young;Chung, Bong-Jun;Kim, Myung-Sub
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.12 no.2
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    • pp.55-61
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    • 1990
  • Patients with facial paralysis, in whom nerve damage is irreparable or in whom the innervation of the paralyzed musculature cannot be restored by nerve suture, grafting, or cross-face nerve transplantation, should be offered some form of reconstructive static and dynamic aid. Temporalis muscle-fascia unit used as a circumorbital sling and motor unit is a dynamic controlled reconstructive procedure, but it has several disadvantages such as wide surgical exposure, bulky-looking at lateral canthal area, insufficient voluntary control. This is a case report of facial palsy of posttraumatic lagophthalmos of 41-year-old male, which was corrected by temporalis muscle-tendon transfer with plantaris tendon transplantation.

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The Development of Ultimate Compressive Strength for Ship Curved Plates (선체곡판의 압축최종강도 설계식의 개발)

  • 박영일;권용우;백점기;이제명;고재용
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.10a
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    • pp.101-109
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    • 2004
  • Ship structures is thin-walled structures and she has lots of curved platings. In these days, lots different kinds of closed-formulas are development for ultimate strength of flat plate but for curved panels, there are not enough study or papers for this field. In this study, the ultimate strength characteristics for ship curved plates are studied. The ship plating is generally subjected to combined in-plane and lateral pressure loads. In-plane loads included biaxial compression/tension and edge shear. This is first report about the developing of ultimate compressive strength for ship curved plating. A closed-form formula for predicting the ultimate compressive strength of curved plates are empirically derived by curve fitting based on the computed results. The results and insights developed in the present study will be useful for damage tolerant design of curved plated structures.

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Structural Performance Evaluation of Repaired Structural Walls (보수된 전단벽의 강도 및 변형능력 회복 여부에 관한 연구)

  • 유승욱;한상환;이리형
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.525-528
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    • 1999
  • Structural walls have been favored for the design of reinforced concrete buildings in seismic zone areas because they provide an efficient bracing system and offer great potential for lateral load resistance and drift control. Loads on structures due to earthquakes are not unlikely to reach, if not exceed, the design load levels. Hence, structural damage to walls is inevitable, and it is necessary to repair this damaged walls. Yet, information on repair method and data related to the strength and deformation characteristics of repaired walls is limited. In this study, specimens which have their aspect ratios of about 1 to 3 will be repaired. For the repairing the damaged walls, new concrete and new reinforcing bar are replaced with cracked concrete and the buckled reinforcing bar, respectively. The objective of this study is to evaluate the performance of the repaired structural walls in the capacity of strength, stiffness, and maximum deformation comparing with the undamaged walls.

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Gate Pier damage assessment by vessel collision (선박충돌에 따른 콘크리트 배수갑문 교각 구조해석)

  • Kim, Kwan-Ho;Cho, Jae-Yong;Cho, Young-Kweon
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.165-166
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    • 2010
  • Collision scenario was 12 cases considering gate location, water level and lateral location of collision etc. And then, analysis result of trunnion by collision loads (reservoir side gate). Compressive fracture may not occur because the maximum compressive stress of concrete is below the allowable compressive strength. but, it is possible to appear some local crack because the maximum tensile stress exceed the tensile strength.

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Application of the Direct Displacement Based Design Methodology for Different Types of RC Structural Systems

  • Malekpour, Saleh;Dashti, Farhad
    • International Journal of Concrete Structures and Materials
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    • v.7 no.2
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    • pp.135-153
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    • 2013
  • This study investigates the direct displacement based design (DDBD) approach for different types of reinforced concrete structural systems including single moment-resisting, dual wall-frame and dual steel-braced systems. In this methodology, the displacement profile is calculated and the equivalent single degree of freedom system is then modeled considering the damping characteristics of each member. Having calculated the effective period and secant stiffness of the structure, the base shear is obtained, based on which the design process can be carried out. For each system three frames are designed using DDBD approach. The frames are then analyzed using nonlinear time-history analysis with 7 earthquake accelerograms and the damage index is investigated through lateral drift profile of the models. Results of the analyses and comparison of the nonlinear time-history analysis results indicate efficiency of the DDBD approach for different reinforced concrete structural systems.

Structural Characteristics of Damaged Offshore Tubular Members

  • Cho, Sang-Rai;Kwon, Jong-Sig;Kwak, Dong-Il
    • Journal of Ocean Engineering and Technology
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    • v.24 no.4
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    • pp.1-7
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    • 2010
  • Over the past few decades various experimental and theoretical investigations have been performed on offshore tubular members with regard to damage resistance and residual strength. Analysis of damaged tubular members requires a three-dimensional shell analysis for accurate results. Even though various commercial packages are available for this purpose, a beam-column analysis is preferred for offshore structural designs. In this paper, empirical equations are provided for a more accurate beam-column analysis of damaged tubes including the relationships between the lateral denting load and the depth of the dent, the rate of dent deepening due to increasing curvature and the longitudinal variation in the dent depth of damaged tubes. A design equation to predict the ultimate bending capacities of damaged offshore tubular members is also presented.

Seismic performance of 1/4-scale RC frames subjected to axial and cyclic reversed lateral loads

  • Bechtoula, Hakim;Sakashita, Masanobu;Kono, Susumu;Watanabe, Fumio
    • Computers and Concrete
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    • v.2 no.2
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    • pp.147-164
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    • 2005
  • This paper summarizes an experimental study on the seismic behavior of lower stories of a mid-rise reinforced concrete frame building. Two reinforced concrete frames with two stories and one span were tested and each frame represents lower two stories of an 11-story RC frame building. Both frames were designed in accordance with Japanese design guidelines and were identical except in the variation of axial force. The tests demonstrated that the overall load-displacement relations of the two frames were nearly the same and the first-story column shear was closely related to the column axial load. The columns and beams elongated during both of the tests, with the second-floor beam elongation exceeding 1.5% of the beam clear span length. The frame with higher axial loads developed more cracks that the frame under moderate axial load.