• Title/Summary/Keyword: Upper structures

Search Result 903, Processing Time 0.026 seconds

Stability Analysis of Upper Structures by Soil Grouting (지반 그라우팅에 의한 상부구조물의 안전성 분석)

  • Hwang, Chulsung
    • Journal of the Korean Society of Safety
    • /
    • v.28 no.4
    • /
    • pp.58-65
    • /
    • 2013
  • Transportation and further expansion of social infrastructure was needed along the development of urbanization and population concentration. To use the underground space due to the lack of availability of land, it is inevitable to intersect between present structure and tunnel during construction. Soil grouting is one of the ground improvement methods to reinforce weak soil around the underground structures by injection of grouting liquid. Some of central columns of an upper structure are damaged during injection of grouting liquid by injection pressure. To investigate and improve the stability of the tunnel, three dimensional analysis are performed with full construction stages which includes the construction of present underpass, damaging columns of the underpass, reinforcing the columns by H-pile and shear walls, and excavation and construct tunnel. The arrangement of grouting holes such as curtain and horizontal type affects largely to the stability of upper structure and horizontal arrangement diminish the shear forces which is the cause of damage of central columns. The liquid injection type of reinforcement for tunnel is not recommended while the presence of upper structure with columns. Wall type reinforcing is utilize for permant support of upper structures which is affected by grouting injection pressure. H-pile is utilize for temporary support, but not for permanent since the sharing of shear forces is not much to shear wall during tunnel construction.

Response modification factor of mixed structures

  • Fanaie, Nader;Shamlou, Shahab O.
    • Steel and Composite Structures
    • /
    • v.19 no.6
    • /
    • pp.1449-1466
    • /
    • 2015
  • Mixed structures consist of two parts: a lower part and an upper part. The lower part is usually made of concrete while the upper part is made of steel. Analyzing these structures is complicated and code-based design of them has many associated problems. In this research, the seismic behavior of mixed structures which have reinforced concrete frames and shear walls in their lower storeys and steel frames with bracing in their upper storeys were studied. For this purpose, seventeen structures in three groups of 5, 9 and 15 storey structures with different numbers of concrete and steel storeys were designed. Static pushover analysis, linear dynamic analysis and incremental dynamic analysis (IDA) using 15 earthquake records were performed by OpenSees software. Seismic parameters such as period, response modification factor and ductility factor were then obtained for the mixed (hybrid) structures using more than 4600 nonlinear dynamic analysis and used in the regression analysis for achieving proper formula. Finally, some formulas, effective in designing such structures, are presented for the mentioned parameters. According to the results obtained from this research, the response modification factor values of mixed structures are lower compared to those of steel or concrete ones with the same heights. This fact might be due to the irregularities of stiffness, mass, etc., at different heights of the structure. It should be mentioned that for the first time, the performance and seismic response of such structures were studied against real earthquake accelerations using nonlinear dynamic analysis, andresponse modification factor was obtained by IDA.

A STUDY ON THE ANTERO-POSTERIOR MORPHOLOGY OF THE UPPER FACE IN ANGLE'S CLASS III MALOCCLUSION PATIENTS (Angle씨 III급 不正交合者(부정교합자) 上顔面(상안면)의 前後方(전후방) 形態(형태)에 관한 硏究(연구))

  • Lee, Jee-Hee;Cha, Kyung-Suk
    • The korean journal of orthodontics
    • /
    • v.24 no.2
    • /
    • pp.395-403
    • /
    • 1994
  • To find out the antero-posterior morphology of the upper face in Angle's class III malocclusion patients, 90 patients, adults in Heilman's Dental age, were used as samples and following results were obtained after the relative comparision of antero-posterior relationship of upper facial structures between Angle's class I malocclusion patients and Angle's class III malocclusion patients and of antero-posterior size of upper facial structures to horizontal and vertical structures in each patients. 1. After comparison of the distance from PMV line to anterior margin of maxillary sinus and cheek, which determines the antero-posterior position of the upper face, upper face in Angle's class III patients are underdeveloped relative to Angle's class I patients. The distance between orbitale and anterior margin of maxillary sinus were greater in Angle's class I patients, whic implies thart the upper face in Angle's class III are depressed. 2. Antero-posterior dimension of anterior cranial base from PMV line and vertical dimension of upper face are statistically insignificant between two groups. After comparing antero-posterior position of upper face to anterior cranial base, the upper face in Angle's class Et patients are depressed antero-posteriorly in relation to anterior cranial base. Following the comparision of antero-posterior position of upper face in relation to vertical dimension of upper face, the upper face in Angle's class III patients seem to be narrow antero-posteriorly

  • PDF

Saturation impulses for dynamically loaded structures with finite-deflections

  • Zhao, Ya-Pu;Yu, T.X.;Fang, J.
    • Structural Engineering and Mechanics
    • /
    • v.3 no.6
    • /
    • pp.583-592
    • /
    • 1995
  • The concept of "Saturation Impulse" for rigid, perfectly plastic structures with finite-deflections subjected to dynamic loading was put forward by Zhao, Yu and Fang (1994a). This paper extends the concept of Saturation Impulse to the analysis of structures such as simply supported circular plates, simply supported and fully clamped square plates, and cylindrical shells subjected to rectangular pressure pulses in the medium load range. Both upper and lower bounds of nondimensional saturation impulses are presented.

The Influence of Artificial Structures on Benthic Macroinvertebrate Communities in Streams (하천의 인공구조물이 저서성 대형무척추동물 군집에 미치는 영향)

  • Kim, Bong Sung;Sim, Kwang Sub;Kim, Sun Hee;Kwon, O Chang;Seo, Eul Won;Lee, Jong Eun
    • Journal of Environmental Science International
    • /
    • v.22 no.3
    • /
    • pp.309-318
    • /
    • 2013
  • This study was conducted for determining the influence of artificial structures on benthic macroinvertebrate communities in stream. Sampling was taken at upper(pool), down(riffle) and control(riffle) from two check dams, two weirs, one agricultural reservoir, and one multipurpose dam in northern part of Gyeongsangbuk-do. The benthic macroinvertebrate communities of these structures were surveyed during 2009 to 2011. The simple habitat of benthic macroinvertebrates occurred at the upper sites due to pooling effects from artificial structures. Specifically, Check dam1, Jusanji, Imha dam showed very low biological attribute values compared to the down and control sites, which have greater difference in substrate characteristics. However, in the upper sites of Check dam2, Weir1 and Weir2, the difference of values of biological attributes was relatively smaller. Also, proportion of functional feeding groups and functional habit groups were relatively simpler at upper stream and the degree of community differences was greater between upper and down, control sites. Spearman's correlation between biological attributes and substrate characteristics, water quality parameters had significant correlations; particularly, the substrate characteristics were more significantly related. In conclusion, the pool caused by artificial structures had negative effects on benthic macroinvertebrate communities thus leading to simplified stream habitats at upper stream ecosystems.

Seismic Response Analysis According to the Height of Substructure of the Dome Structure Using Mid-Story Isolation System (중간층 면진을 적용한 돔 구조물의 하부 구조 높이에 따른 지진 응답 분석)

  • Choi, Na-Young;Kim, Hyun-Su;Kang, Joo-Won
    • Journal of Korean Association for Spatial Structures
    • /
    • v.19 no.4
    • /
    • pp.27-34
    • /
    • 2019
  • Spatial structure does not have columns and walls installed inside, so they have a large space. There are upper structure and substructure supporting them. The response of seismic loads to the upper structure may be increased or decreased due to the effects of the substructure. Therefore, in this study, the seismic response of the upper structure and the floor response spectrum of the substructure were compared and analyzed according to the height of the substructure in the spatial structure where the LRB was installed. As a result, the possibility of amplification of response was confirmed as seismic waves passed though the substructure, which is likely to increase the response of the upper structures.

Key Pose-based Proposal Distribution for Upper Body Pose Tracking (상반신 포즈 추적을 위한 키포즈 기반 예측분포)

  • Oh, Chi-Min;Lee, Chil-Woo
    • The KIPS Transactions:PartB
    • /
    • v.18B no.1
    • /
    • pp.11-20
    • /
    • 2011
  • Pictorial Structures is known as an effective method that recognizes and tracks human poses. In this paper, the upper body pose is also tracked by PS and a particle filter(PF). PF is one of dynamic programming methods. But Markov chain-based dynamic motion model which is used in dynamic programming methods such as PF, couldn't predict effectively the highly articulated upper body motions. Therefore PF often fails to track upper body pose. In this paper we propose the key pose-based proposal distribution for proper particle prediction based on the similarities between key poses and an upper body silhouette. In the experimental results we confirmed our 70.51% improved performance comparing with a conventional method.

A Study for Transfer Girder Details of the Upper-Wall and Lower-Frame Structures (주상복합구조의 전이보 상세설계기법 연구)

  • 이한선;김상연;고동우
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2000.10a
    • /
    • pp.529-534
    • /
    • 2000
  • Hybrid building structure, which comprise both the residential and commercial spaces in a building, are composed of upper shear-walls and lower frames. In these hybrid structures, the structural analysis and design of transfer systems which link upper-wall and lower-frame are crucial. The available structural design methods for the transfer girder are performed by taking a prototype structure, and the details of transfer girder based on these design methods are presented and compared with regard to the dimensions and amount of reinforcements.

  • PDF

Surgical anatomy for Asian rhinoplasty: Part II

  • Kim, Taek Kyun;Jeong, Jae Yong
    • Archives of Craniofacial Surgery
    • /
    • v.21 no.3
    • /
    • pp.143-155
    • /
    • 2020
  • Surgical anatomy for Asian rhinoplasty Part I reviewed layered anatomy with neurovascular system of the nose. Part II discusses upper two-thirds of nose which consists of nasal bony and cartilaginous structures. Nasal physiology is mentioned briefly since there are several key structures that are important in nasal function. Following Part III will cover lower one-third of nose including in-depth anatomic structures which are important for advanced Asian rhinoplasty.

Experimental Study on the Structural Capacity of the U-Flanged Truss Steel Beam (U-플랜지 트러스 보의 구조 내력에 관한 실험 연구)

  • Oh, Myoung Ho;Kim, Young Ho;Kang, Jae Yoon;Kim, Myeong Han
    • Journal of Korean Association for Spatial Structures
    • /
    • v.18 no.4
    • /
    • pp.113-121
    • /
    • 2018
  • U-flanged truss beam is composed of u-shaped upper steel flange, lower steel plate of 8mm or more thickness, and connecting lattice bars. Upper flange and lower plate are connected by the diagonal lattice bars welded on the upper and lower sides. In this study the structural experiments on the U-flanged truss beams with various shapes of upper flange were performed, and the flexural and shear capacities of U-flanged truss beam in the construction stage were evaluated. The principal test parameters were the shape of upper flange and the alignment space of diagonal lattice bars. In all the test specimens, the peak loads were determined by the buckling of lattice bar regardless of the upper flange shape. The test results have shown that the buckling of lattice bar is very important design factor and there is no need to reinforce the basic u-shaped upper flange. However, the early lattice buckling occurred in the truss beam with upper steel bars because of the insufficient strength and stiffness of upper chord, and the reinforcement in the upper chord is necessary. The formulae of Eurocode 3 (2005) have presented more exact evaluations of lattice buckling load than those of KBC 2016.