• Title/Summary/Keyword: Diaphragm Wall

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Equivalent lateral force method for buildings with setback: adequacy in elastic range

  • Roy, Rana;Mahato, Somen
    • Earthquakes and Structures
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    • v.4 no.6
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    • pp.685-710
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    • 2013
  • Static torsional provisions employing equivalent lateral force method (ELF) require that the earthquake-induced lateral force at each story be applied at a distance equal to design eccentricity ($e_d$) from a reference resistance centre of the corresponding story. Such code torsional provisions, albeit not explicitly stated, are generally believed to be applicable to the regularly asymmetric buildings. Examined herein is the applicability of such code-torsional provisions to buildings with set-back using rigid as well as flexible diaphragm model. Response of a number of set-back systems computed through ELF with static torsional provisions is compared to that by response spectrum based procedure. Influence of infill wall with a range of opening is also investigated. Results of comprehensive parametric studies suggest that the ELF may, with rational engineering judgment, be used for practical purposes taking some care of the surroundings of the setback for stiff systems in particular.

A Study on the Compression of Construction Period by the Improvement of Trench Excavation for Slurry Wall Method (지하연속벽 시공 시 트렌치 굴착방법 개선을 통한 공기단축에 관한 연구: 현장적용사례를 중심으로)

  • Lee, Young Soo;Park, Hyung-Keun;Kang, Kyubyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5D
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    • pp.499-505
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    • 2012
  • As the excavation depths during excavation works in urban sites are getting deeper and bigger, It is necessary to study for the improvements to solve the problems in the excavation processes. This research deals with the excavation method that can not only minimize the effect on the surrounding constructions, but also shorten the construction period of the excavation work. For this research, there have been an extensive literature review of the bibliographic data about Slurry Wall Method, which is recognized around the world, and the analysis of the major problems in the existing ineffective construction step. These efforts led to the technical improvements. Accordingly, a new construction method applied with the new technical factors has been suggested, and it was possible to compare Slurry Wall Method with the construction method and analyze them on the base of the examples using the suggested method. This new method decreased the excavation period by 15 days. It took only 33days to finish the excavation work, as compared to 48 days that can be seen on the pre-modification schedule. Furthermore, the suggested method in this research is safer, more economically feasible, and better for the environment than Slurry Wall Method. It will contribute to shortening the construction period of Slurry Wall Method in the end.

Evaluation of Flexural Behavior of Hollow Prestressed Concrete Pile for Continuous Pile Wall (주열식 벽체용 중공 프리스트레스트 콘크리트 파일의 휨거동 평가)

  • Lee, Young-Geun;Jang, Min-Jun;Yoon, Soon-Jong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.3
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    • pp.20-27
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    • 2014
  • In the construction site, various earth retaining systems are developed and applied to maintain stability of excavated area and structures. Among the methods, the underground continuous wall and the column-type diaphragm wall methods are especially used in construction site nearby buildings or roads. However, these methods have some disadvantages such as the difficulty of quality control and long curing time because these methods need to cast fresh concrete at the construction site. In addition, these methods are usually applied to the site for the temporary purpose. In this paper, we suggest precast hollow prestressed concrete pile for continuous pile wall system. To investigate the structural behavior of suggested pile, which is the main member of the suggested system, tests pertaining to the structural behavior and prestressing force applied in the pile are conducted. From the test results, it was found that the prestressing force measured is sufficient compared with the value obtained by the design equation and the cracking moment measured is 34% higher than the design value. In addition to the above, this precast hollow prestressed concrete pile has an additional safety margin that the maximum moment is 59.2% higher than the cracking moment which is one of the serviceability limits for the design of the system.

M-mode Ultrasound Assessment of Diaphragmatic Excursions in Chronic Obstructive Pulmonary Disease : Relation to Pulmonary Function Test and Mouth Pressure (만성폐쇄성 폐질환 환자에서 M-mode 초음파로 측정한 횡격막 운동)

  • Lim, Sung-Chul;Jang, Il-Gweon;Park, Hyeong-Kwan;Hwang, Jun-Hwa;Kang, Yu-Ho;Kim, Young-Chul;Park, Kyung-Ok
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.4
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    • pp.736-745
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    • 1998
  • Background: Respiratory muscle interaction is further profoundly affected by a number of pathologic conditions. Hyperinflation may be particularly severe in chronic obstructive pulmonary disease(COPD) patients, in whom the functional residual capacity(FRC) often exceeds predicted total lung capacity(TLC). Hyperinflation reduces the diaphragmatic effectiveness as a pressure generator and reduces diaphragmatic contribution to chest wall motion. Ultrasonography has recently been shown to be a sensitive and reproducible method of assessing diaphragmatic excursion. This study was performed to evaluate how differences of diaphragmatic excursion measured by ultrasonography associate with normal subjects and COPD patients. Methods: We measured diaphragmatic excursions with ultrasonography on 28 healthy subjects(l6 medical students, 12 age-matched control) and 17 COPD patients. Ultrasonographic measurements were performed during tidal breathing and maximal respiratory efforts approximating vital capacity breathing using Aloka KEC-620 with 3.5 MHz transducer. Measurements were taken in the supine posture. The ultrasonographic probe was positioned transversely in the midclavicular line below the right subcostal margin. After detecting the right hemidiaphragm in the B-mode the ultrasound beam was then positioned so that it was approximately parallel to the movement of middle or posterior third of right diaphragm. Recordings in the M-mode at this position were made throughout the test. Measurements of diaphragmatic excursion on M-mode tracing were calculated by the average gap in 3 times-respiration cycle. Pulmonary function test(SensorMedics 2800), maximal inspiratory(PImax) and expiratory mouth pressure(PEmax, Vitalopower KH-101, Chest) were measured in the seated posture. Results: During the tidal breathing, diaphragmatic excursions were recorded $1.5{\pm}0.5cm$, $1.7{\pm}0.5cm$ and $1.5{\pm}0.6cm$ in medical students, age-matched control group and COPD patients, respectively. Diaphragm excursions during maximal respiratory efforts were significantly decreased in COPD patients ($3.7{\pm}1.3cm$) when compared with medical students, age-matched control group($6.7{\pm}1.3cm$, $5.8{\pm}1.2cm$, p< 0.05}. During maximal respiratory efforts in control subjects, diaphragm excursions were correlated with $FEV_1$, FEVl/FVC, PEF, PIF, and height. In COPD patients, diaphragm excursions during maximal respiratory efforts were correlated with PEmax(maximal expiratory pressure), age, and %FVC. In multiple regression analysis, the combination of PEmax and age was an independent marker of diaphragm excursions during maximal respiratory efforts with COPD patients. Conclusion: COPD subjects had smaller diaphragmatic excursions during maximal respiratory efforts than control subjects. During maximal respiratory efforts in COPD patients, diaphragm excursions were well correlated with PEmax. These results suggest that diaphragm excursions during maximal respiratory efforts with COPD patients may be valuable at predicting the pulmonary function.

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Current Status of General Thoracic Surgery in Korea (한국의 일반 흉부수술 현황)

  • 전영진
    • Journal of Chest Surgery
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    • v.25 no.5
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    • pp.504-510
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    • 1992
  • Overall 25,095 cases of general thoracic surgery were analysed, which were performed by 48 institutes in Korea during recent 6 years[242 hospital-years]. The proportions of tumorous disease and infectious disease to be operated were 6,864 cases[27.4%] and 6,775 cases [27.0%], The most common organ involved for operation was lung-bronchus 16,542 cases [69.5%], and remainders were pleura 2,500 [10.0%], esophagus 2,433[9.7%], mediastinum 1,902[7.6%], chest wall 1,297 [5.2%], and diaphragm 421 [1.7%] in order. Among 6,864 cases of tumorous diseases, the most common causes for operation were lung-bronchus tumor 3132 cases [45.6%] and most of them were lung cancer 2,731 cases [88.7%]. In the 2,019 cases of primary lung cancer with known cell type, squamous cell carcinoma 1,296 cases [64.2%] and adenocarcinoma 460 cases [22.8%] were the most. The common types in the 1,207 cases of mediastinal tumor with known cell type were neurogenic tumor 348 cases [28.8%], thymoma 311 [25.8%], and teratoma 252[20.9%]. The annual cases of operation for tumorous disease including malignant tumor were increased steadily. Operation for infectious lung diseases [including bronchiectasis and tuberculosis] were about twice common than infectious pleural disease [i.e. empyema], and operations for tuberculous disease occupied about half cases of infectious lung disease. In 11,456 cases of other disease entities, excluding tumorous and infectious disease, there were bullous lung disease 9,074 cases[79.2%], benign esophageal disease 484[4.2%], myasthenia gravis 356[3.1%], chest wall deformity 483[4.2%], and diaphragmatic lesion 421[3. 7%] in order. We propose that above results for inquiry can be used as the basic data of general thoracic surgery in Korea.

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A CFD Study on the Combustion Pressure Oscillation by a Location of a Pressure Transducer inside Closed Vessel (밀폐용기 연소실험 시 센서위치에 따라 변화하는 압력 진동에 대한 수치적 연구)

  • Han, Doo-hee;Ahn, Gil-hwan;Ryu, Byung-tae;Sung, Hong-gye
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.2
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    • pp.66-73
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    • 2018
  • A computational fluid dynamics simulation of pyrotechnic material combustion inside a cylindrical closed vessel was carried out using the Eulerian-Lagrangian method. The 5th order upwind WENO scheme and the improved delayed detached eddy turbulence model were implemented to capture shock waves. The flow structure was analyzed inside the cylindrical vessel with a pressure sensor installed at the side wall center. The analysis revealed that the pressure oscillated because of the shock wave vibration. Additionally, the simulation results with four different sensor tab depths implied that, inside the sensor tab, eddies were generated by the excessively large gap between the sensor diaphragm and the side wall. These eddies caused irregularity to the measured time-pressure curve, which is an undesirable characteristic.

Evaluation of Load Transfer Characteristics of Barrette Pile Based on Bi-directional Loading Tests (양방향 재하시험결과를 활용한 바렛말뚝의 하중전이특성 평가)

  • Park, Seong Wan;Lim, Dae Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.2C
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    • pp.41-49
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    • 2009
  • Due to the increased size of civil infrastructure and the cost of materials, the needs exists for utilizing large sized cast-inplace piles in lieu of conventional precast piles. Among them, the barrette pile has become more commonly used in fields where a diaphragm wall is the retaining wall, to improve workability and economical efficiency, and to ensure hole stability under deep soil layers. In this paper, the bearing capacity and displacement characteristics of the barrette pile are evaluated by using the bi-directional loading test data obtained from four different sites. In addition, the design value of pile shaft resistance, ${\beta}$, is assessed with previous literatures and load transfer analysis. Finally, numerical analyses were performed to analyze the load-displacement behavior, and the interface effect on the piles, using the 3-dimensional finite element method.

Extensive Rib Osteosarcoma with Intraperitoneal Invasion in a Small Breed Dog: Clinical and Histopathologic Findings

  • Lim, Chae-Young;Yoo, Jong-Hyun;Park, Chul;Jung, Dong-In;Kim, Ju-Won;Kang, Byeong-Teck;Kim, Ha-Jung;Sur, Jung-Hyang;Park, Hee-Myung
    • Journal of Veterinary Clinics
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    • v.25 no.3
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    • pp.182-186
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    • 2008
  • An 11-year-old mixed breed male dog was presented with a thoracoabdominal wall mass of 3-year duration. Initial tentative diagnosis of osteosarcoma was made. Despite chemotherapy treatment, 72 days following the date of presentation, the dog was euthanized. Based upon necropsy and histopathologic findings, the tumor was definitely diagnosed as a combined type osteosarcoma of the rib. At necropsy examination, the tumor extended the left kidney and diaphragm, but distant metastasis was not found. The tumor's weight was 2.3kg and that was 38.3% of the dog's weight. This case report describes the clinicopathological, computed tomographic, histopathologic and immunohistochemical findings of extensive rib osteosarcoma in a small breed dog.

Supradiaphragmatic Heterotopic Liver Presenting as a Pleural Mass: A Case Report

  • An, Jung-Suk;Han, Joung-Ho;Lee, Kyung-Soo;Choi, Yong-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.69 no.3
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    • pp.191-195
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    • 2010
  • Abnormally located liver tissue has been described in the vicinity of the liver proper, near anatomical structures such as the gallbladder, the umbilical fossa, the adrenal gland, the pancreas, and the spleen. Supradiaphragmatic ectopic liver is a rare finding, but has been reported to have been found in the intrathoracic cavity and in the pericardium. In the majority of supradiaphragmatic ectopic liver cases, there was an accompanying transdiaphragmatic pedicle of the main liver body into the abdominal cavity. In a minority of supradiaphramatic ectopic liver cases, the liver was completely separated from the abdominal cavity without a connection between the thorax and the abdomen, with accompanying diaphragmatic anomalies. We describe one case of intrathoracic ectopic liver in a patient with a previous history of lower chest wall trauma, and a brief review of the English-language medical literature on this topic.

Performance-based Design of 300 m Vertical City "ABENO HARUKAS"

  • Hirakawa, Kiyoaki;Saburi, Kazuhiro;Kushima, Souichirou;Kojima, Kazutaka
    • International Journal of High-Rise Buildings
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    • v.3 no.1
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    • pp.35-48
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    • 2014
  • In designing a 300 meter high skyscraper expected to be the tallest building in Japan, an earthquake-ridden country, we launched on the full-scale performance based design to ensure redundancy and establish new specifications using below new techniques. The following new techniques are applied because the existing techniques/materials are not enough to meet the established design criteria for the large-scale, irregularly-shaped building, and earth-conscious material saving and construction streamlining for reconstructing a station building are also required: ${\bullet}$ High strength materials: Concrete filled steel tube ("CFT") columns made of high-strength concrete and steels; ${\bullet}$ New joint system: Combination of outer diaphragm and aluminium spray jointing; ${\bullet}$ Various dampers including corrugated steel-plate walls, rotational friction dampers, oil dampers, and inverted-pendulum adaptive tuned mass damper (ATMD): Installed as appropriate; and ${\bullet}$ Foundation system: Piled raft foundation, soil cement earth-retaining wall construction, and beer bottle shaped high-strength CFT piles.