• 제목/요약/키워드: Lateral

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교대말뚝기초의 측방이동 판정기준 분석 (Design Guidelines of Piled Bridge Abutment subjected to Lateral Soil Movements)

  • 정상섬;이진형;서동희;김유석;장범수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.381-388
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    • 2002
  • A series of centrifuge model tests were performed to investigate the behavior of piled bridge abutment subjected to lateral soil movements induced by the construction of approach embankment. In these tests, both the depth of soft clay and the rate of embankment construction are chosen as key parameters to examine the effects on lateral soil movements. The depth of soft clay layer varies from 5.2 m to 11.6 m, and the rate of embankment construction has two types of staged construction(1m/30days, 1m/15days) and instant construction. It is shown that, the distribution of lateral flow induced by stage embankment construction has a trapezoidal distribution. And practical guidelines to check the possibility of some lateral movement of piled abutment were investigated. The validity of the proposed guidelines by centrifuge test was compared with the observed performance by lateral movement index, F(Japan Highway Public Corporation) and modified I index(Korea Highway Corporation). Based on the results obtained, the critical values of F and modified I, as a practical guidelines, are proposed to 0.03 and 2.0, respectively.

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A Study on Comparison between Center of Lateral Resistance and Pivot Point being Used in Handling Ships at the Present Time

  • Jeong, Tae-Gweon
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2012년도 추계학술대회
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    • pp.160-161
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    • 2012
  • The traditional theory regarding the pivot point of a ship during maneuvering, so called apparent pivot point, is located nearly at 1/3 ship's length from the bow when the ship is moving ahead, and between 1/4 ship's length from the stern and the rudder post when going astern. The pivot point is sometimes considered to be the centre of leverage for forces acting on the ship. However, the pivot point is located out of ship due to strong lateral force, such as current and it is very inconvenient to use during maneuvering a ship. In this paper firstly, pivot points due to ship's condition are investigated carefully. And then the center of lateral resistance used at the present are determined. While a new lateral force is added, we can compare the pivot point with the center of lateral forces. Finally, we will suggest the center of all lateral forces for maneuvering instead of pivot point. Especially, it will be very helpful for pilots to handle ships in simulation.

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850 nm GaAs/AlGaAs MQW LD의 Lateral-mode 특성 연구 (Analysis of Lateral-mode Characteristics of 850-nm MQW GaAs/(Al,Ga)As Laser Diodes)

  • 양정택;곽정근;최안식;김태경;최우영
    • 한국광학회지
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    • 제32권2호
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    • pp.55-61
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    • 2021
  • 850 nm 대역의 발진 파장을 갖는 GaAs/AlGaAs 다중양자우물 레이저 다이오드의 lateral-mode 특성과 이 특성이 출력 광파워 kink에 미치는 영향을 조사하였다. 이를 위해 전기적-열적-광학적 시뮬레이션을 self-consistent하게 수행하고, 제작된 레이저 다이오드 소자들을 측정하였다. 연구 결과를 바탕으로 높은 출력 파워에서도 single lateral-mode를 유지해서 좋은 beam quality를 유지할 수 있는 최적의 P-cladding 두께를 결정하였다.

Optimal lateral load pattern for pushover analysis of building structures

  • Habibi, Alireza;Saffari, Hooman;Izadpanah, Mehdi
    • Steel and Composite Structures
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    • 제32권1호
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    • pp.67-77
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    • 2019
  • Pushover analysis captures the behavior of a structure from fully elastic to collapse. In this analysis, the structure is subjected to increasing lateral load with constant gravity one. Neglecting the effects of the higher modes and the changes in the vibration characteristics during the nonlinear analysis are the main obstacles of the proposed lateral load patterns. To overcome these drawbacks, whereas some methods have been presented to achieve updated lateral load distribution, these methods are not precisely capable to predict the response of structures, precisely. In this study, a new method based on optimization procedure is developed to obtain a lateral load pattern for which the difference between the floor displacements of pushover and Nonlinear Dynamic Analyses (NDA) is minimal. For this purpose, an optimization problem is considered and the genetic algorithm is applied to calculate optimal lateral load pattern. Three special moment resisting steel frames with different dynamic characteristics are simulated and their optimal load patterns are derived. The floor displacements of these frames subjected to the proposed and conventional load patterns are acquired and the accuracy of them is evaluated via comparing with NDA responses. The outcomes reveal that the proposed lateral load distribution is more accurate than the previous ones.

Experimental study on shear damage and lateral stiffness of transfer column in SRC-RC hybrid structure

  • Wu, Kai;Zhai, Jiangpeng;Xue, Jianyang;Xu, Fangyuan;Zhao, Hongtie
    • Computers and Concrete
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    • 제23권5호
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    • pp.335-349
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    • 2019
  • A low-cycle loading experiment of 16 transfer column specimens was conducted to study the influence of parameters, likes the extension length of shape steel, the ratio of shape steel, the axial compression ratio and the volumetric ratio of stirrups, on the shear distribution between steel and concrete, the concrete damage state and the degradation of lateral stiffness. Shear force of shape steel reacted at the core area of concrete section and led to tension effect which accelerated the damage of concrete. At the same time, the damage of concrete diminished its shear capacity and resulted in the shear enlargement of shape steel. The interplay between concrete damage and shear force of shape steel ultimately made for the failures of transfer columns. With the increase of extension length, the lateral stiffness first increases and then decreases, but the stiffness degradation gets faster; With the increase of steel ratio, the lateral stiffness remains the same, but the degradation gets faster; With the increase of the axial compression ratio, the lateral stiffness increases, and the degradation is more significant. Using more stirrups can effectively restrain the development of cracks and increase the lateral stiffness at the yielding point. Also, a formula for calculating the yielding lateral stiffness is obtained by a regression analysis of the test data.

외측상과염의 추나 치료에 대한 체계적 문헌 고찰 (Chuna Manual Therapy for Lateral Epicondylitis: A Systematic Review)

  • 한다영;이지윤;남수현;손정민;정다해;조혜미
    • 한방재활의학과학회지
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    • 제32권3호
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    • pp.65-75
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    • 2022
  • Objectives This study was conducted to analyze the therapeutic effect of Chuna therapy for lateral epicondylitis. Methods Key words such as lateral epicondylitis and Chuna were searched in 10 databases (National Digital Science Library [NDSL], Oriental Medicine Advanced Searching Integrated System [OASIS], Research Information Sharing Service [RISS], Koreanstudies Information Service [KISS], KMBASE, Cochrane Library, PubMed, EMBASE, J-STAGE, China Academic Jurnals [CAJ]), and only suitable randomized controlled trials (RCTs) were selected. Results 8 RCTs were finally selected, and Chuna therapy showed positive results for lateral epicondylitis compared to western medicine, acupuncture, warm-acupuncture and Chinese medicine iontophoresis. Conclusions In this study, we finally reviewed 8 studies about Chuna therpay used for lateral epicondylitis. The studies showed that Chuna therapy is effective in treating lateral epicondylitis. However, because all of selected studies were found in Chinese database, more high-quality clinical trials about Chuna therapy for lateral epicondylitis are needed in Korea.

Simulation of monopile-wheel hybrid foundations under eccentric lateral load in sand-over-clay

  • Zou, Xinjun;Wang, Yikang;Zhou, Mi;Zhang, Xihong
    • Geomechanics and Engineering
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    • 제28권6호
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    • pp.585-598
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    • 2022
  • The monopile-friction wheel hybrid foundation is an innovative solution for offshore structures which are mainly subjected to large lateral eccentric load induced by winds, waves, and currents during their service life. This paper presents an extensive numerical analysis to investigate the lateral load and moment bearing performances of hybrid foundation, considering various potential influencing factors in sand-overlaying-clay soil deposits, with the complex lateral loads being simplified into a resultant lateral load acting at a certain height above the mudline. Finite element models are generated and validated against experimental data where very good agreements are obtained. The failure mechanisms of hybrid foundations under lateral loading are illustrated to demonstrate the effect of the friction wheel in the hybrid system. Parametric study shows that the load bearing performances of the hybrid foundation is significantly dependent of wheel diameter, pile embedment depth, internal friction angle of sand, loading eccentricity (distance from the load application point to the ground level), and the thickness of upper sandy layer. Simplified empirical formulae is proposed based on the numerical results to predict the corresponding lateral load and moment bearing capacities of the hybrid foundation for design application.

Lateral impact behaviour of concrete-filled steel tubes with localised pitting corrosion

  • Gen Li;Chao Hou;Luming Shen;Chuan-Chuan Hou
    • Steel and Composite Structures
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    • 제47권5호
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    • pp.615-631
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    • 2023
  • Steel corrosion induces structural deterioration of concrete-filled steel tubes (CFSTs), and any potential extreme action on a corroded CFST would pose a severe threat. This paper presents a comprehensive investigation on the lateral impact behaviour of CFSTs suffering from localised pitting corrosion damage. A refined finite element analysis model is developed for the simulation of locally corroded CFSTs subjected to lateral impact loads, which takes into account the strain rate effects on concrete and steel materials as well as the random nature of corrosion pits, i.e., the distribution patterns and the geometric characteristics. Full-range nonlinear analysis on the lateral impact behaviour in terms of loading and deforming time-history relations, nonlinear material stresses, composite actions, and energy dissipations are presented for CFSTs with no corrosion, uniform corrosion and pitting corrosion, respectively. Localised pitting corrosion is found to pose a more severe deterioration on the lateral impact behaviour of CFSTs due to the plastic deformation concentration, the weakened confinement and the reduction in energy absorption capacity of the steel tube. An extended parametric study is then carried out to identify the influence of the key parameters on the lateral impact behaviour of CFSTs with localised pitting corrosion. Finally, simplified design methods considering the features of pitting corrosion are proposed to predict the dynamic flexural capacity of locally pitted CFSTs subjected to lateral impact loads, and reasonable accuracy is obtained.

석회성 외측 상과병증의 초음파 유도 하 세척흡인술과 체외충격파치료의 병행 (Chronic Intractable Calcific Lateral Epicondylopathy Treated with Ultrasound-Guided Barbotage Combined with Extracorporeal Shock-Wave Therapy)

  • 김건우;윤경재;도종걸;황진태;이용택
    • Clinical Pain
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    • 제18권2호
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    • pp.138-141
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    • 2019
  • Lateral epicondylopathy represents pain in the lateral (radial aspect) of the elbow caused by degeneration in the common extensor tendon. Calcium deposit frequently developes in lateral epicondylopathy, with the prevalence up to 46%. There are considerable debates on its treatment protocols for lateral epicondylopathy so far, likewise, the effective treatment method for calcific lateral epicondylopathy has not been established. We report here a case of chronic intractable calcific lateral epicondylopathy treated with ultrasound-guided barbotage and focused type extracorporeal shock wave therapy (ESWT). To our knowledge, this is the first report of calcific lateral epicondylopathy treated by ultrasound-guided barbotage combined with ESWT.

시공 중 풍하중에 의한 PSC 교량 거더의 횡방향 거동 해석 (Analysis of Lateral Behavior of PSC Bridge Girders under Wind Load During Construction)

  • 이종한;김경환;조백순
    • 콘크리트학회논문집
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    • 제27권4호
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    • pp.377-385
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    • 2015
  • PSC I 거더의 장경간화는 단면의 세장비와 자중의 영향 등을 증가시켜 거더의 횡적 불안정에 대한 위험성을 높였다. 특히 최근에는 시공 중 거더의 전도 붕괴사고가 증가하고 있어 거더의 횡적 불안정성에 대한 평가 기술이 절실히 요구되고 있다. 따라서, 본 연구에서는 시공 중 전도 붕괴의 한 원인으로 판단되어지고 있는 풍하중에 대하여 PSC I 거더의 횡방향 거동 특성과 안정성을 평가하였다. 거더의 횡방향 불안정성은 주로 거더의 길이와 받침의 강성 변화에 의해 영향을 받는다. 해석결과에 의하면 거더의 경간장이 증가함에 따라 거더의 횡적 불안정성을 유발할 수 있는 임계 풍하중은 감소하고, 거더의 변형과 회전각, 받침의 회전각은 모두 증가하였다. 최종적으로 시공 시 PSC I 거더의 임계 풍하중과 임계 횡변위량을 계산할 수 있는 해석식을 제시함으로써, 시공 시 거더의 횡적 안정성을 유지하기 위한 정량적 관리 수치를 제공할 수 있으리라 판단된다.