• Title, Summary, Keyword: JES Method

Search Result 268, Processing Time 0.054 seconds

A Study on the Joint Element Connection of Joint Element Structure Method (JES 공법의 JOINT ELEMENT 이음부에 관한 연구)

  • 엄기영;박명준
    • Journal of the Korean Society for Railway
    • /
    • v.5 no.3
    • /
    • pp.133-141
    • /
    • 2002
  • Recently developed JES(Joint Element Structure) Method was researched as a more safe and economic method than other under pass construction method and was applied to many construction sites. The joint element connection of JES Method is the most important factor for the to behavior of structure. The connection of JES method is filled with the mortar, and the steel and mortar of connections produce the same behavior as one material. The results of experience and numerical analysis are following: The maximum internal stress of connection is decided by the end of connection. also, The connection of joint element structure method have sufficient internal stress against fatigue.

Joint Element Structure Method on the Subway Box Structure unere Railroad (철도하부 가도교 설치에 대한 JES공법)

  • Pi, Tae-Hee;Cho, Kook-Hwan;SaGong, Myung
    • Proceedings of the KSR Conference
    • /
    • /
    • pp.973-981
    • /
    • 2008
  • This document presents the JES(Joint Element Structure) method that has been adopted for the firs time in our country for the construction of the structure crossing under the railroad without open excavation. Front Jacking Method, Tubular Roof Construction Method, New Tubular Roof Method and Joint Element Structure Method are commonly used for the construction of structures crossing under the railroad. JES Method, frequently used in Japan recently, is a new method to construct the structures crossing under the railroad in a safe manner and in a relatively short period of time by utilizing the steel elements with the joints through which the load in the vertical angle to the axial direction is transferred to the next element. The elements are tied to each other through the joints to form the permanent walls of a Rahmen structure under the road without open excavation and without limitation to the length in a convenient way. Through the case study in the project of a Subway Box Culvert Improvement for the Gyeonguiseon Railroad in front of Yonsei University using the JES Method, the cost and period of construction in various types of soil is investigated compared to the Front Jacking Method. Furthermore, by analyzing the results of instrumentation measurements carried out throughout the construction, comparison between the actual displacement in the ground and the predicted displacement in the design is made to provide the considerations to be counted for the design. In conclusion, comparison in the field of economic feasibility, constructability and safety between the JES Method and Front Jacking Method, which is most frequently adopted in our country at present, is made to present the JES Method as a new alternative for the non-open excavation construction method for the structures crossing under the railway.

  • PDF

The design and construction with the JES method used steel elements for under pass in korea and the practical use of the JES method (강재 엘리먼트를 이용한 기계식 UNDER PASS 공법(JES 공법)의 국내 적용 사례 및 활용 방안 연구)

  • Jeong, Gyeong-Hwan;Jung, Sun-Tae;Kim, Do-Hyeong;Kim, Jung-Sung;Hwang, Young-Chul;Park, Min-Kwan
    • Proceedings of the KSR Conference
    • /
    • /
    • pp.1498-1508
    • /
    • 2009
  • Recently, the expansion of roads are necessary because the population and vehicles have rapidly increased, but those are restricted because of the limited site. JES(Jointed Element Structure) method is the method of the new cross-structure, which is element-traction method which draws and excavates elements under the existing structure with high accuracy within a short time. Also JES(Jointed Element Structure) method has a facility of the economical execution, a small effect on the train-service during construction period and no limit of the crossing length under the trade In this study, the tractive force and settlement are compared with the upper element, side wall element and the lower element respectively in the section which the JES method is applied In the case of element located at left side wall, the tractive force measured by a guage is double or more than the tractive force calculated by a formula. It is expected that many boulder contented in the ground contrary to the site investigation data cause high tractive force. For comparison of the settlement, the settlement as excavating the upper element is the largest in all steps. It is expected that this is the same as the cause of high tractive force. Also in this study, the practical use of the JES method when some under pass structures are extended in the future is studied.

  • PDF

Improvement of Rating-curve by HEC-RAS (HEC-RAS를 이용한 수위-유량곡선의 개선방안)

  • Lee, Yeong Hwa;Lee, Chang Su;Park, Gi Beom
    • Journal of Environmental Science International
    • /
    • v.13 no.9
    • /
    • pp.759-765
    • /
    • 2004
  • HEC-RAS model is used for estimation of rating-curve of Musung in Wi stream. Discharge is computed from stage estimated by HEC-RAS model, is compared with the discharge of water surface slope method. The relative deviation of observed and computed discharge is 5.37%, and shows as a good results. A rating-curve by HEC-RAS model shows better results than by water surface slope method.

Variability of Surface Water Properties in the Japan/East Sea on Different Time Scales

  • Ponomarev, Vladimir;Rudykh, Natalya;Dmitrieva, Elena;Ishida, Hajime
    • Ocean and Polar Research
    • /
    • v.31 no.2
    • /
    • pp.177-187
    • /
    • 2009
  • This study examined the multi-scale variabilities of sea surface temperature (SST) and salinity in the Japan/East Sea (JES) based on statistical analyses of observational data, with a focus on the northwestern part of the sea. The regionality of JES SST variability was estimated for different frequency ranges on semimonthly (11-17 days), monthly to seasonal (30-90 days), quasi-semiannual (157-220 days), and quasi-biennial (1.5-3 years) time scales using cluster analyses of daily gridded SST data for 1996 to 2007 from the Japan Meteorological Agency (JMA). Several significant peaks and regional cores were found in each frequency range of the SST anomaly (SSTA) oscillations. Quasi-semiannual SSTA oscillations with high amplitude were found in the south-southwestern part of the Japan Basin ($41-43^{\circ}N$) and were amplified in the area adjacent to Peter the Great Bay. Oscillations with periods of 79 and 55 days also prevailed over the southwest Japan Basin between the Yamato Rise and the continental slope. A similar method was applied to classify SST and the annual cycle of surface salinity using Generalized Digital Environmental Model (GDEM) gridded data. The Tatarskii Strait and adjacent area showed the most specific annual cycles and variability in salinity on interannual to interdecadal time scales. The most significant inverse relationship between surface salinity in the Tatarskii Strait and southern JES areas was found on the interdecadal time scale. Linkages of sea water salinity in the Tatarskii Strait with Amur River discharge and wind velocity over Amurskii Liman were also revealed.

Development of Multi-Residue Methods for Carbamate Pesticides by the Enzyme Inhibition Test (효소 저해법을 이용한 Carbamate계 농약의 다성분 잔류분석법 개발)

  • Kim, Jung-Ho
    • Journal of Environmental Science International
    • /
    • v.17 no.12
    • /
    • pp.1325-1330
    • /
    • 2008
  • This study was carried out with the detection for multiresidue of the carbamate pesticide such as carbaryl and cabofuran by enzyme-inhibition method. The check time for determination of acetylcholinesterase(AChE) activity was selected at 60 sec. The AChE activity in chicken brain determined by the Ellman's method was $162{\mu}$mol/min/g protein. $I_{50}$ for AChE by carbamate pesticide with wet kit was 0.169mg/L of carbaryl and 0.089mg/L of cabofuran, respectively. The incubation time for enzyme kit with substrate kit was 30min for determination of AChE activity. Enzyme kit with substrate kit was stable at $4^{\circ}C\;and\;25^{\circ}C$ for 5 days. Limit detection concentration of carbaryl with dry kit for AChE was 0.05mg/L. The dry kit such as wet kit applied Enzyme-Inhibition(EI) method with AChE was confirmed the multi residue method to detect the carbamate pesticides.

Relationship between Image-processed Color Content and Human Color Visibility Estimation of Natural Forest Scenes

  • Yhang, Wii-Joo
    • Journal of Environmental Science International
    • /
    • v.11 no.8
    • /
    • pp.765-771
    • /
    • 2002
  • The current study investigated the relationship between image processed data and human visibility data for natural forest scenes from the perspective of color. In particular, the results indicated relatively low Pearson product-moment correlations between the color ratings obtained from the two methods used in the study. The first method measured the color content of slides using a image processing program, while the second used a panel of human judges to rate the color content of each slide.

The Management Planning of Pollutant Loading Allocation in the Kumho River Basin (금호강 유역의 오염총량 관리 대책 수립)

  • 황병기;정효준
    • Journal of Environmental Science International
    • /
    • v.11 no.10
    • /
    • pp.1125-1131
    • /
    • 2002
  • This study was performed to plan pollutant loading allocation by sub-watershed at Kumho river basin located in the north Kyeongsang province. HEC-geoHMS which is extension program of ArcView was used to extract sub-watershed. To simulate water quality, Qua12eu model was calibrated and validated. BOD was simulated under several scenarios to evaluate reduction effects of pollutant loading. Uniform treatment and transfer matrix method was considered. Effects of headwater flow rate and efficiency waste water treatment plant were also considered.

Visualization of Thecal Plates of Lightly Armored Dinoflagellates Cryptoperidiniopsis brodyi and Pfiesteria piscicida (Dinophyceae) (유각 와편모조류 Pfiesteria piscicida (Dinophyceae)의 형태분석)

  • Park, Tae-Gyu;Bae, Heon-Meen;Kang, Yang-Soon
    • Journal of Environmental Science International
    • /
    • v.18 no.1
    • /
    • pp.15-19
    • /
    • 2009
  • Early studies claimed that heterotrophic dinoflagellates Pfiesteria piscicida and related genera may produce a putative water-soluble toxin that causes death of fish and other marine animals. Several methods were tested to visualize plate morphology of Cryptoperidiniopsis brodyi and Pfiesteria piscicida. Cellulose plates of cells were exposed and visualized- by a membrane stripping method using Triton X-100. While calcofluor M2R white stain could readily bind to the thecal plates, details of the plate tabulation were difficult to observe. Fixation with osmium tetroxide $(OsO_4)$ produced well preserved cells with little morphological distortion, but thecal plates could not be visualized. Scanning electron microscopy (SEM) observation using the membrane stripping method showed distinctive plate tabulations between C. brodyi and P. piscicida suggesting that this method is a useful tool for morphological identification of lightly armored dinoflagellates.

Uncertainty Analysis for Parameter Estimation of Probability Distribution in Rainfall Frequency Analysis Using Bootstrap (강우빈도해석에서 Bootstrap을 이용한 확률분포의 매개변수 추정에 대한 불확실성 해석)

  • Seo, Young-Min;Park, Ki-Bum
    • Journal of Environmental Science International
    • /
    • v.20 no.3
    • /
    • pp.321-327
    • /
    • 2011
  • Bootstrap methods is the computer-based resampling method that estimates the standard errors and confidence intervals of summary statistics using the plug-in principle for assessing the accuracy or uncertainty of statistical estimates, and the BCa method among the Bootstrap methods is known much superior to other Bootstrap methods in respect of the standards of statistical validation. Therefore this study suggests the method of the representation and treatment of uncertainty in flood risk assessment and water resources planning from the construction and application of rainfall frequency analysis model considersing the uncertainty based on the nonparametric BCa method among the Bootstrap methods for the assessement of the estimation of probability rainfall and the effect of uncertainty considering the uncertainty of the parameter estimation of probability in the rainfall frequency analysis that is the most fundamental in flood risk assessement and water resources planning.