• Journal of the Korean Society of Hazard Mitigation
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• v.1 no.3 s.3
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• pp.103-110
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• 2001

The objective of this study is to investigate the behavior of superstructure considering several factors such as change of pile rigidity, soil characteristics, and the constraint condition of support. The results of this study are as follows: 1. Pile-rigidity computed by the rotating deformed plane method is continuously varied up to approximately 5D(D=diameter of pile) below the ground level. This result is consistent with the previous study$^{(12)}$, in which the pile deformation occurs at approximately $3{\sim}6$ times of pile diameter from the ground level. 2. For bridge structure-pile system, analytical results of internal forces and deformations show different values for modified pile rigidity and unchanged pile rigidity. 3. Detaild analysis considering modified pile rigidity is required for the long-span bridge design with structure pile system.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.253-259
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• 2000

This thesis investigated the behavior of super structure by varying the factors such as the change of pile rigidity, the characteristics of soil and the constraint condition of support. The results of this study are as follows; 1. The pile rigidity in the Fig 3.3 computed by the rotating deformed plane method becomes the elastic range at approximately about 5.1 m (D : 1.0 m) below the ground level. This result is consistent with the previous study that the pile deformation occurs approximately 3 to 6 times pile diameter from the pile head. 2. The values of forces and deformations for the structure-pile system in Y-direction appeared larger than that in X-direction, since the pile rigidity and constraint condition of support were changed as shown Fig.3.5 to 3.8. 3. The current practice for the analysis of structure-pile system has not considered the variation of pile rigidity and the constraint condition of support. So, the analysis of structure-pile system with large difference in super-structure rigidity must includes these factors in both X and Y directions.

• Journal of the Korean Geosynthetics Society
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• v.17 no.1
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• pp.33-43
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• 2018

Two-row Overlap Pile wall is a novel retaining wall system with high flexural rigidity and waterproofing for deep excavation support currently being developed in Korea. The Two-row Overlap Pile wall is constructed by making an overlap between consecutive four-axis (or two-axis) auger piles which themselves are overlapped and arranged in zigzag manner. In this study, the flexural rigidity of the Two-row Overlap Pile wall, including the effect of cross-sectional shape, was examined using both theoretical and numerical approaches. The results of investigation suggested that the Two-row Overlap Pile wall formed with two-row piles exhibit greatly higher flexural rigidity than conventional one-row pile walls such as Cast in place pile (CIP) and Secant pile wall (SPW), whereas the effect of overlap length between piles on the flexural rigidity is relatively minimal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2505-2510
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• 2013

Parametric studies on nonhomogeneous pile and homogeneous pile installed in clay were performed through the developed technique to investigate the effects of considered factors on the lateral pile behaviors. Values of the parameters with embedment depths of the two piles having different flexural rigidity show that values of the parameters for more rigid pile were greater than those for smaller one. Parameters for the case of the nonhomogeneous pile were converged to the same ones of the homogeneous pile as nodal point moves away from point of material boundary. In order to determine adequate upper length of the nonhomogeneous pile, changing patterns of the parameters, lateral displacement, member forces and so forth should be compared.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1C
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• pp.41-51
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• 2008

The load distribution and deformation of single piles which is embedded in Jumunjin sand and Kimhae clay are investigated, based on small scale model tests. Special attention is given to the consideration of flexural rigidity in laterally loaded piles. To consider the flexural rigidity of the pile, tests are performed with the aluminium piles of three different length under different relative densities and undrained shear strength. The test results indicate that the initial slope from the results of tests is proportional to the depth and pile-soil rigidity in both soils. But the increasing rate of the initial slope in the clay is less than in the sand. In addition, the soil resistance is more related to the depth and soil condition than the pile rigidity. Base on the test results, an empirical formula is proposed, which is good agreement with previously published small scale model test and field lateral load test.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.109-118
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• 2018

Two-row overlap pile wall, currently under development for use in deep excavations, is a novel retaining structure designed to perform itself as a cutoff wall as well as a high-stiffness wall by constructing four overlapping piles arranged in zigzag manner at a time using a tetra-axis auger. This wall has a relatively complex cross-section, compared with other types of pile wall, which would make it difficult to determine design parameters related to cross-section. In this study, a flexural rigidity equation has been derived by analyzing both theoretically and statistically various wall cross-sections with different pile diameters and overlap lengths. The flexural rigidity equation was found to show the maximum error rate of 3%.

• Polymer(Korea)
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• v.35 no.5
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• pp.385-389
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• 2011

In rubbing process, process factors, the properties of alignment layer and the physical properties of rubbing cloth have acted as important variables. These factors affect the orientation properties of the alignment layer by rubbed extent that is determined by rubbing density and rubbing force. In this work, we studied the effects of rubbing cloths with different pile density and rigidity on rubbing density(length) and rubbing force. As the pile density and rigidity of rubbing cloths increased, the birefringence and the surface roughness of the rubbed alignment layers became bigger, but the characteristics of rubbing-effect had differed each other. The pile density of rubbing cloths which was related with the number of pile, affected the rubbing density(length). On the other hand, the pile rigidity of rubbing was closely related to rubbing force rather than the rubbing density(length).

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.6
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• pp.1039-1047
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• 1996

The purpose of this study is to examine and to evaluate the properties of pile materials to produce velvet fabrics which have excellent handle. In order to perform this purpose, the mechanical properties, hand value (H.V.), total hand value (T.H.V.), total appearance value (T.A.V.) of acetate, cuprammonium rayon, cotton materials for velvet as the typical commercial Pile fabric were measured and analyzed by KES-F system. The important results obtained by this study are as follows. 1 For acetate pile, elogational deformation was easy and bending rigidity of weft was high and elastic recovery was excellent compared with the other materials. 2. Cuprammonium rayon velvet was shown that pile bending rigidity and hysterisis were low. Cotton velvet was shown that compressional energy was high and compressinal elasticity was exellent. 3. In the case that specimens were applied by men's winter suit program, H.V was shown that Koshi of acetate velvet was similar to that of cotton. Numeri of cuprammonium rayon velvet was higher than the others and Fukurami values for all of the three fabrics were similar. 4. But in case that specimens were applied by women's winter suit program Koshi of cuprammonium rayon velvet was lower. But Numeri of that was higher than the others and Fukurami for all of the three fabrics were similar and Sofutosa of cotton velvet was lower than the others. T.H.V. of the acetate velvet was the highest in men's winter suit program while cuprammonium rayon velvet was the highest in women's winter suit program T.A.V. of acetate velvet was highest.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1C
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• pp.31-40
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• 2008

This study presents the assessment of pseudostatic approach for obtaining the internal response of Single Column/Shaft subjected to earthquake loading. In numerical procedure, various lateral load transfer characteristics (p-y curve and Bi-linear curve) were used to model the nonlinear behavior of soil reactions including soil-pile interaction. The analysis using nonlinear soil model could estimate the seismic performance of soil-pile system, despite its relative simplicity. It was found that lateral behavior of single column/shaft obtained from the response displacement method was larger than those by seismic intensity method. To investigate the effects of soil-pile rigidity and pile head condition on the internal pile response, parametric studies were carried out for various soil models. The results from numerical analysis showed that lateral deflection was decreased with fixed condition of pile head and decreasing the soil-pile rigidity. The seismic analysis using Bi-linear model of JRA could reasonably predict the lateral behavior of Single Column/Shaft.

• Journal of Astronomy and Space Sciences
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• v.35 no.4
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• pp.219-225
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• 2018

Cosmic rays are ions that move at relativistic speeds. They generate secondary cosmic rays by successive collisions with atmospheric particles, and then, the secondary particles reach the ground. The secondary particles are mainly neutrons and muons, and the neutrons are observed by the ground neutron monitor. This study compared the diurnal variation in cosmic ray intensity obtained via harmonic analysis and that obtained through the pile-up method, which was examined in a previous study. In addition, we analyzed the maximum phase of the diurnal variation using four neutron monitors with a cutoff rigidity below approximately 6 GV, located at similar longitudes to the Oulu and Rome neutron monitors. Expanding the data of solar cycles 20-24, we examined the time of the maximum cosmic ray intensity, that is, the maximum phase regarding the solar cyclic modulation. During solar cycles 20-24, the maximum phase derived by harmonic analysis showed no significant difference with that derived by the pile-up method. Thus, the pile-up method, a relatively straightforward process to analyze diurnal variation, could replace the complex harmonic analysis. In addition, the maximum phase at six neutron monitors shows the 22-year cyclic variation very clearly. The maximum phase tends to appear earlier and increase the width of the variation in solar cycles as the cutoff rigidity increases.