• Title/Summary/Keyword: Column rib

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Experimental study on reinforced concrete filled circular steel tubular columns

  • Hua, Wei;Wang, Hai-Jun;Hasegawa, Akira
    • Steel and Composite Structures
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    • v.17 no.4
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    • pp.517-533
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    • 2014
  • Experimental results of 39 specimens including concrete columns, RC columns, hollow steel tube columns, concrete filled steel tubular (CFT) columns, and reinforced concrete filled steel tubular (RCFT) columns are presented. Based on the experimental results, the load-carrying capacity, confined effect, ductility, and failure mode of test columns are investigated. The effects of the main factors such as width-thickness ratio (the ratio of external diameter and wall thickness for steel tubes), concrete strength, steel tube with or without rib, and arrangement of reinforcing bars on the mechanical characteristics of columns are discussed as well. The differences between CFT and RCFT are compared. As a result, it is thought that strength, rigidity and ductility of RCFT are improved; especially strength and ductility are improved after the peak of load-displacement curve.

A Clinical Observation of the Traumatic Sternal Fracture (흉골 골절에 대한 임상적 고찰)

  • 심재영
    • Journal of Chest Surgery
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    • v.23 no.5
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    • pp.916-921
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    • 1990
  • Clinical observations were performed on 17 cases of the traumatic sternal fracture, those were admitted and treated at the department of thoracic and cardiovascular surgery in Chosun University Hospital during the past 6 years 5months period from January 1983 to May 1989. Obtained results were as follows: 1. The frequency was about 4.8% of the nonpenetrating chest trauma. 2. The ratio of male to female was 16: 1 in male predominance and age distribution was from 24 to 62 years old. 3. The common cause were high decelerating injury [impact of the steering column] and falling down[more than 3 m in high]. 4. The most common fracture site was sternal body and next was sternomanubrial junction. 5. Associated intrathoracic organ injuries were cardiac contusion [6 cases], hemopneumothorax[1 Case], mediastinal bleeding[1 case], and thoracic cage and extrathoracic organ injuries were rib fracture, head injuries, thoracic spinal fracture, and long bone fracture. 6. Abnormal EGG findings were sinus bradycardia[1 case], bundle branch block [2 cases], and sinus tachycardia[3 cases]. 7. The operative reduction and fixation was necessary in only one case and the others were treated with conservative treatment.

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A basic study of reinforcement tools development for Productivity Improvement of Composite PC connection work (합성 PC 구조 접합부공사의 생산성 향상을 위한 철근배근 도구 개발 기초연구)

  • Kim, Geun-Ho;Lim, Chae-yeon;Na, Young-Joo;Kim, Sun-Kuk
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.05a
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    • pp.339-340
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    • 2012
  • Green frame is combined by structural steel and reinforcements of Green column and beam and unified by cast-in-place concrete. However, when upper reinforcements penetrate structural steel hole, the execution is difficult due to interference of joint and a rib of deformed reinforcements. Therefore, the objective of this study is to propose the reinforcement tools to improve productivity of precast structure connection construction. The reinforcement tools proposed in this study can be helpful to improve constructability, safety, duration, and cost comparing with conventional reinforcement method since unskilled workers can deal with reinforcements easily.

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Cystic Echinococcosis of the Pelvic Bone with Recurrences: A Case Report

  • Jain, Sunila;Chopra, Prem
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.277-279
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    • 2011
  • Hydatid cysts commonly affect the liver and the lung. However, they rarely involve bones with vertebral column. We hereby report a case of a female patient with cystic echinococcosis of the hip bone and ilium. She presented with a long history of frequent recurrences highlighting the dismal prognosis at this rare site. Resection of the hydatid cyst from the sacroiliac region was done with allograft and autograft (rib graft) with lumbosacroiliac fixation. Follow-up of the patient at 6 months showed no detectable abnormality on radiology and the patient was doing well.

Seismic Evaluation of Exposed Column-base Plate Weak-axis Connections Using L-shaped Hooked Anchor Bolts (L형 갈고리 앵커볼트를 사용한 약축방향 노출형 주각부의 내진성능 평가)

  • Lim, Woo-Young;You, Young-Chan
    • Journal of Korean Society of Steel Construction
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    • v.29 no.4
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    • pp.269-280
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    • 2017
  • In this study, seismic performance was evaluated for the exposed column-base plate weak-axis connections of small size steel structures through cyclic loading tests. The primary test parameters are the thickness of base plate, the presence of rib plates, the number of anchor bolts and embedment length of anchor bolts. To investigate the effect of bond performance of anchor bolts on the seismic performance of column-base plate connections, L-shaped round bars and thread bars were used as the hooked anchor bolts in the test specimens. Test results showed that bond performance of anchor bolts and the thickness of base plate significantly affect the structural performance and energy dissipation capacity. In particular, it was found that even if the requirements for minimum thickness of the base plate that is satisfied, the base plate can yield before the capacity of steel column reaches the plastic moment resulting in decreasing the structural performance of the connections. However, the proposed details of the connections might be considered as the partially restrained, that is semi-rigid connections. Consequently, the L-shaped thread anchor bolts is applicable in the exposed column-base plate weak-axis connections of small-size steel structures.

Seismic Performance Evaluation of Beam-Column Connection for Panel Zone Strength (패널존의 강도비에 따른 기둥-보 접합부의 내진성능 평가)

  • Kim, Sung-Young;Shin, Chang-Hoon
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.1 s.24
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    • pp.11-20
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    • 2007
  • The study proposes the method to cancel the scallop to avoid fracture of the circumstance of the scallop at H shape column-to-beam connection and reinforce at beam flange two faces with the cover plates and rib. A total of four specimens were tested to enhance seismic performance of building structure by reducing the frequency of stress concentration and preventing the brittle fracture of scallop. For this purpose, four full-scale test specimens were made and loaded with quasi-static reversed cyclic loading. The main analytical parameters are panel-zone-strength ratio, yield strengths, initial stiffness, total plastic rotation, contribution of each element to total plastic rotation and energy dissipation capability. For the specimens tested under repeated loading, the experimental result was satisfied with seismic performance requirement as the Special Moment Frames (SMF). The analysis results show that all of the test specimens were found to have good performance to 4% story drift and satisfied the criteria for the plastic roation capacity of SMFs that is 0.03 rad. according to the 1997 AISC seismic provision.

Intraosseous hemangioma of the orbit

  • Choi, June Seok;Bae, Yong Chan;Kang, Gyu Bin;Choi, Kyung-Un
    • Archives of Craniofacial Surgery
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    • v.19 no.1
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    • pp.68-71
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    • 2018
  • Intraosseous hemangioma is an extremely rare tumor that accounts for 1% or fewer of all osseous tumors. The most common sites of its occurrence are the vertebral column and calvaria. Occurrence in a facial bone is very rare. The authors aim to report a case of the surgical treatment of intraosseous hemangioma occurring in the periorbital region, which is a very rare site of occurrence and to introduce our own experiences with the diagnosis and treatment of this condition along with a literature review. A 73-year-old male patient visited our hospital with the chief complaint of a mass touching the left orbital rim. A biopsy was performed by applying a direct incision after local anesthesia. Eventually, intraosseous hemangioma was diagnosed histologically. To fully resect the mass, the orbital floor and zygoma were exposed through a subciliary incision under general anesthesia, and then the tumor was completely eliminated. Bony defect was reconstructed by performing a seventh rib bone graft. Follow-up observation has so far been conducted for 10 months after surgery without recurrence or symptoms.

Retrograde Analysis of Clinical Characteristics of Bone Metastasis in 1,031 Cases of Preliminarily Diagnosed Nasopharyngeal Carcinoma

  • Zhao, Chang-Lin;Qian, Guo-Qiang;Chen, Xiao-Yin;Chen, Chao
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3785-3788
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    • 2014
  • Purpose: To explore the clinical characteristics of bone metastasis (BM) in a large sample of preliminarily diagnosed nasopharyngeal carcinomas (NPCs). Methods: The sample consisted of 1,031 patients diagnosed with NPC at first visitg clinics between October 1989 and June 2012. Several parameters including metastasis locus, T/N staging, diagnosis, therapy and prognosis of BM were analyzed retrospectively. Results: In 70 patients who had been preliminarily diagnosed with BM, the incidence of BM in N0, N1, N2 and N3 stage was 5.7%, 17.2%, 50.2%, and 25.7%, respectively, while the incidence in T0, T1, T2 and T3 stage was 0%, 23.8%, 47.6% and 28.6% respectively. BM occurred in most common in vertebral column, rib, sternum, ilium and femur. Positive rate of Epstein-Barr virus antibody was 77.6%. The median survival time was 12 months. Conclusion: The incidence of BM in NPC preliminarily diagnosed is about 7% and it is related to N classification but not T classification.

Osteological Development of Korean Striped Bitterling, Acheilognathus yamatsutae (Cyprinidae) (줄납자루, Acheilognathus yamatsutae (잉어과)의 골격 발달)

  • Song, Ho-Bok;Son, Yeong-Mok
    • Korean Journal of Ichthyology
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    • v.17 no.1
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    • pp.19-28
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    • 2005
  • Osteolgical development of Korean striped bitterling, Acheilognathus yamatsutae (Cyprinidae), were investigated using cartilage and bone staining. The parasphenoid, dentary, pterygoid, ceratohyal, branchial arch and parts of the caudal skeleton were formed first as cartilaginous elements at $6.82{\pm}0.08mm$ total length (TL). Formation of frontal, parietal, and maxillary were notable at $7.76{\pm}0.09mm$ TL, and the proximal radial, scapula,and coracoid in the pectoral girdle were developed at this stage. At the same time, the neural and hemal spine were present in the caudal vertebra. The opercle and branchiostegals were observed at $9.68{\pm}0,14mm$, and the posttemporal was formed at $12.9{\pm}40.64mm$ TL, respectively. Ossification in the parasphenoid, pharyngeal bone, dentary, premaxillary, maxillary, and opercle began at about $9.68{\pm}0.14mm$ TL. The cleithrum, supracleithrum, urostyle, and caudal fin were calcified at this stage. The vertebral column was formed and ossified at $11.52{\pm}0.13mm$ TL, and the frontal, preopercle, subopercle, and hyomandibular were ossified at $15.30{\pm}0.68mm$ TL. This fish was late in developing the skeletal formation and ossification as compared with other fishes.