원심모형시험에 의한 복개터널 복공의 변위특성에 관한 연구

이명욱,박병수,이종호,유남재 강원대학교 산업기술연구소 2003 産業技術硏究 Vol.23 No.A

This thesis is results of experimental works on the behavior of the cut-and-cover tunnel. Centrifuge model tests were performed to simulate the behavior of the cut-and-cover tunnels having cross sections of national road and subway tunnels Model experiments were carried out with changing the cut slope and the slope of filling ground surface Displacements of tunnel lining resulted from artificially accelerated gravitational force up to 40g of covered material used in model tests, were measured during centrifuge model tests In model tests. Jumunjin Standard Sand with the relative density of 80 % and the zinc plates were used for the covered material and the flexible tunnel lining. respectively Basic soil property tests were performed to obtain it's the property of Jumumjin Standard Sand Shear strength parameters of Jumunjin Standard Sand were obtained by performing the triaxial compression tests Direct shear tests were also carried out to find the mechanical properties of the interface between the lining and the covered material Compared results model tests estimation with respect to displacements of the lining

원심모형시험에 의한 복개터널 복공의 토압특성에 관한 연구

이명욱,박병수,정길수,유남재 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.B

This thesis is results of experimental works on the behavior of the cut-and-cover tunnel. Centrifuge model tests were performed to simulate the behavior of the cut-and-cover tunnels having cross sections of national road and subway tunnels. Model experiments were carried out with changing the cut slope and the slope of filling ground surface. Displacements of tunnel lining resulted from artificially accelerated gravitational force up to 40g of covered material used in model tests, were measured during centrifuge model tests. In model tests, Jumunjin Standard Sand with the relative density of 80 % and the zinc plates were used for the covered material and the flexible tunnel lining, respectively. Basic soil property tests were performed to obtain it's the property of Jumumjin Standard Sand. Shear strength parameters of Jumunjin Standard Sand were obtained by performing the triaxial compression tests. Direct shear tests were also carried out to find the mechanical properties of the interface between the lining and the covered material. Compared results model tests estimation with respect to displacements of the lining.

수치해석에 의한 복개터널 라이닝의 변위거동

이명욱,박병수,전용배,유남재 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.A

This paper is results of experimental and nunerical works on the behavior of the cut-and-cover tunnel. Centrifuge model tests were performed to simulate the behavior of the cut-and-cover tunnels having cross sections of national road and subway tunnels. Model experiments were carried out with changing the cut slope and the slope of filling ground surface. Displacements of tunnel lining resulted from artificially accelerated gravitational force up to 40g of covered material used in model tests, were measured during centrifuge model tests. In model tests, Jumunjin Standard Sand with the relative density of 80% and the zinc plates were used for the covered material and the flexible tunnel lining, respectively. Basic soil property tests were performed to obtain it's the property of Jumumjin Standard Sand. Shear strength parameters of Jumunjin Standard Sand were obtained by performing the triaxial compression tests. Direct shear tests were also carried out to find the mechanical properties of the interface between the lining and the covered material. Numerical analysis with the commercially available program of FLAC were performed to compare with results of centrifuge model experiment. In numerical modelling. Mohr-Coulomb elasto-plastic constitutive model was used to simulaye the behavoor of Jumunjin Standard Sand and the interface element between the lining and the covered material was implemented to simulate the interaction between them. Compared results between model tests and numerical estimation with respect to displacement of the lining showed in good agreements.

경사진 사석층의 지지력에 관한 원심모형실험 및 수치해석

이명욱,박병수,정길수,유남재 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.B

This paper is an experimental and numerical research works about the effects of the bearing capacity of sloped rubble mound on the density of rubble mound and the position of footing. Centrifuge model tests were performed to investigate the bearing capacity of rubble mound by changing the density of rubble mound and the location of loading in forms of strip loading to simulate the caisson. Materials of rubble mound used in the model tests were crushed rocks having similar value of uniformity coefficient to the value in field. Two different relative densities of 80% and 90% were prepared during tests. The dimens ions of centrifuge model were trapezoidal shape of model mound having the bottom width of mound, 30cm and height of mound, 10cm. Gravity level applied during the centrifuge test was 50G. Surcharge loading in the forms of strip loading was applied on the top of the sloped model mound. Tests were carried out by changing the position of loadi ng. The rigid model footing was located in the center of top of the model rubble mound and the edge of model footing was at the crest of mound. Test results were analyzed by using the limit equilibrium methods proposed by Meyer hof(1957) and Bowles(1982) and the numerical approach with FLAC being available commercially software. For the numerical estimations with FLAC, the rubble mound was simulated with the constitutive relationship of Mohr-Coulomb elasto-plastic model.

N/O/N 박막 다이아프레임을 이용한 광섬유 압력센서의 제작 및 그 압력특성

유양욱,김명규,박동수,김창원,김진섭,이정희,손병기 경북대학교 센서기술연구소 1995 센서技術學術大會論文集 Vol.6 No.1

The 0.6 μm N/O/N triple layer, Si_(3)N_(4)(150 nm)/SiO_(2)(300 nm)/Si_(3)N_(4)(150 nm), was deposited on silicon substrate and the N/O/N thin film diaphragm was formed using anisotropic etching technique. The stress of the formed diaphragm was very small with temperature variations. Combining this diaphragm and the optical fiber, intensity-type pressure sensor was fabricated and its pressure characteristics were investigated. The relation between the optical output power, inversely proportional to the deflection of the diaphragm, and the applied pressure was almost linear in 0~77 torr range.

준설토의 건조수축에 의한 강도증가 특성과 지지력에 관한 연구

유남재,이종호,이명욱,김현주 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.A

This research is results of experimental and numerical works on characteristic of strength increase and bearing capacity in dredged and reclaimed soil due to desiccation shrinkage. For a soil sampled from southern coastal area in Korea, basic soil property tests and standard consolidation test with falling head permeability tests were carried out to obtain consolidational characteristics of soil. Double cone penetration test. laboratory vane test and unconfined compression test were also performed to investigate the change of shear strength with degree of desiccation. Model tests were performed in 1G environment and 30G level artificially accelerated condition by using the centrifuge model test facilities to investigate the bearing capacity of desiccated ground. Test results were analyzed by using the bearing capacity of desiccated ground. Test results were analyzed by using the theoretical and load-settlement characteristics method proposed by Meyehof & Hanna(1978). On the other hands, the numerical technique, using the finite strain consolidation theory considering the effect of desiccation was used to estimate the appropriate time of using heavy construction equipments in field with respect to strength increase due to desiccation.

과재하중 재하에 따른 역 T형 옹벽의 활동거동에 관한 수치해석

유남재,이명욱,박병수,이승주 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.B

This paper is experimental and numerical research about the sliding behavior of cantilever retaining walls resisting surcharge loads. In experimental research, centrifuge model tests at the 1g and 40g-level were performed by changing the location of model footing and its width. Bearing capacity of model footing and characteristics of load-settlement and load-lateral displacement of retaining wall were investigated. Test results of bearing capacity were compared with modified jarquio method, based on the limit equilibrium method with elasticity theory. For the numerical analysis, the commericially available program of FLAC was used by implementing the hyperbolic constitutive relationships to compare with test result about load-settlement and load-displacement of retaining wall, bearing capacity of strip footing.

有限變形率 壓密理論에 의한 軟弱 粘土의 一次元 壓密에 관한 數値 解析的 연구

鄭潤和,李明旭,兪南在 江原大學校 産業技術硏究所 1991 産業技術硏究 Vol.11 No.-

A numerical study was performed to investigate characteristics of one-dimensional consolidation of soft clay. Results of consolidation tests with the remolded normally consolidation clay of having a very high initial void ratio were analyzed by using the numerical technique of finite difference method based on the finite strain consolidation theory, to evaluate consolidational characteristics of soft clay under surcharges on the top of clay. On the other hand, a numerical parametric study on soft clay consolidated due to its self-weight was also carried out to find its effect on one-dimensional consolidation. Terzaghi's conventional consolidation theory, finite strain consolidation theories with linear and non-linear interpolation of effective stress-void ratio -permeability realtion were used to analyze the test results and their results were compared to each other to figure out the difference between them.Therefore, the validity of theories was assessed.

터널의 지보방법에 관한 遠心模型實驗

유남재,이명욱,박병수 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.B

This research is experimental thesis to prepare the structural safety of the upper bridge for support type on tunnel and the effect of settlement. Unit weight test and uni-axial compression test have been performed to simulate the physical property of foundation on the tunnel. Tunnel model of slip form type for centrifuge model has been developed to performed the tunnel excavation while field stress is activated. And the support type of tunnel such as umbrella arch method and large diameter steel pipe reinforce method has been tested for the centrifuge model. After the analysis of experiment, results show that internal displacement of large diameter steel pipe reinforce method is smaller than that of the umbrella arch method.

상재하중에 의한 연약점토의 일차원 압밀에 관한 원심모형실험

유남재,이명육,이종호 江原大學校 産業技術硏究所 1997 産業技術硏究 Vol.17 No.-

This thesis is to investigate the one-dimensional consolidation behavior of soft marine clay with uniform surcharges by performing numerical and experimental works. Parametric experimental works of centrifuge model test were carried out changing test conditions of gravitational level in centrifuge, magnitude of surcharges and construction sequence of applying surcharges. Results of centrifuge model experiments were analyzed by using the numerical technique of explicit finite difference method based on the finite strain consolidation theory, being known to be appropriate to analyze the consolidational behavior of soft clay with a very high initial void ratio using the Lagrangian and the material coordinate systems. Test result were in relatively good agreements with analyzed results in terms of excess pore pressure dissipation and consolidation settlement with time and final void ratio distribution.