• Journal of the Korean Geosynthetics Society
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• v.11 no.1
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• pp.11-21
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• 2012

The Rankine(1857)'s earth pressure and the Hong and Yun(1995a)'s earth pressure was applied to analyze the lateral displacement of diaphragm wall applied to the Top-Down construction method using the computer program, which is a common design program for diaphragm wall. The lateral displacement estimated by the computer program was compared with the lateral displacement measured by inclinometer. The Rankine's earth pressure has been widely used to design the diaphragm wall in the analysis of computer program. As the result of comparison, the lateral displacement of diaphragm wall was predicted differently according to the applied earth pressures. The behavior of lateral displacement predicted by the Rankine's earth pressure was different with displacement measured by inclinometer and the lateral displacement at the bottom part was overestimated. However, the lateral displacement predicted by the Hong and Yun's earth pressure is similar to the behavior and maximum value of real displacement. Therefore, the Hong and Yun's earth pressure is more suitable than the Rankine' earth pressure to design the diaphragm walls applied to the Top-Down Construction Method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.129-137
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• 2020

In performing the structural analysis, the foundation is considered to be a fixed end as a plastic hinge model. In this study, the displacements of the foundation, pier, and shoe were compared when the foundation modeled as a fixed end, a shallow foundation constructed on bedrock of 2m depth, and a pile foundation constructed in the 10m to 20m depth of bedrock. The shear force was also compared, and the probability of damage was calculated and compared for the critical condition. When calculated as a fixed end, the displacement of the foundation converged to 0mm, but the shallow foundation built on the bedrock with a depth of 2m caused relatively displacement, and the pile foundation constructed to contact the bedrock with a depth of 18m caused a larger displacement. In addition, it was analyzed that the displacement of the foundation, which is the lower structure, affects the displacement of the super structure, but the difference in shear force applied to the foundation was insignificant in the three cases. There was no difference between the shallow foundation and the pile foundation in the influence on the displacement of the top of the pier, but there was a big difference from the analysis assuming as a fixed end.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.573-580
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• 2014

In this paper, axial strains and lateral displacements of columns in a 58-story reinforced concrete building were measured using vibrating wire gauge and laser scanner, respectively, and compared with predicted values. Predictions were obtained using ASAP, which is a 3D construction stage analysis program developed based on PCA report. Comparisons indicated that columns in the middle of floor plan showed good correlation with predictions. However, the columns in the corners showed some deviations. Lateral displacement of columns between measurement and estimation showed similar trends but considerable deviations, which are seemingly caused by construction error of column faces, and inaccuracy in differential vertical displacement prediction.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.4
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• pp.17-25
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• 2006

Thermo-mechanical behavior of flip-chip plastic ball grid array (FC-PBGA) packages are characterized by high sensitive $moir\'{e}$ interferometry. $Moir\'{e}$ fringe patterns are recorded and analyzed for several temperatures. Deformation analysis of bending displacements of the packages and average strains in the solder balls for both single and double-sided package assemblies are presented. The bending displacement of the double-sided package assembly is smaller than that of the single-sided one because of its symmetric structure. The largest effective strain occurred at the solder ball located on the edge of the chip and its magnitude of the double-sided package assembly is greater than that of single-sided one by 50%.

• Journal of the Korean GEO-environmental Society
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• v.9 no.4
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• pp.53-61
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• 2008

Various components including wave scattering, wave passage, and site amplification effects cause the ground motion to vary spatially. The spatially varying ground motion can significantly influence the dynamic response of longitudinal structures such as bridges and tunnels. While its effect on bridges has been extensively studied, there is a lack of study on its effect on underground tunnels. This paper develops a new procedure for simulating the tunnel response under spatially varying ground motion. The procedure utilizes the longitudinal displacement profile, which is developed from spatially variable ground motion time histories. The longitudinal displacement profile is used to perform a series of pseudo-static three dimensional finite element analyses. Results of the analyses show that the spatially variable ground motion cause longitudinal bending of the tunnel and can induce substantial axial stress on the tunnel lining. The effect can be significant at boundaries at which the material properties of the ground change in the longitudinal direction.

• Journal of the Korean Geosynthetics Society
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• v.22 no.1
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• pp.75-85
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• 2023

In areas where excavation works are carried out, it is very important to select a retaining wall method to minimize ground water level and ground subsidence changes. In this regard, the use of Secant Pile Wall(SPW) method, which can complement the disadvantages of the CIP method, is gradually domestic increasing for the construction of retaining wall method. This study investigated the design elements of the SPW method and the interrelationship between the structural stability factors of the wall. The design elements for the retaining method are the overlap length between piles, pile diameter, and the specifications of the H-Beam specifications, while the structural stability factors of the wall are the bending stress, shear stress, horizontal displacement, and concrete strength. The study results showed that the pile diameter and H-Beam specifications have a significant impact on the capacity of the H-Beam, the overlap length and pile diameter have a significant impact on the horizontal displacement, and the pile diameter and H-Beam specifications have a significant impact on the required strength of the concrete.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.3
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• pp.195-206
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• 2011

The capacity spectrum method(CSM) has been more frequently used as a tool to evaluate the seismic capacity of the structure. Many formulas of strength reduction factors(SRF) have been proposed and adopted to generate the inelastic demand spectrum for the CSM. This study evaluates the impacts of the type of the SRF on the inelastic demand spectrum and finally on the seismic response displacement of curved bridge. For the purpose, the several existing formulas of SRFs were comparatively investigated through the case study. Curved bridges with different subtended angles were selected and the displacements of the bridge piers were estimated by using the different formulas of SRFs. Nonlinear time history analyses were also performed for the validation purpose of the CSM results. According to study results, the CSM may generate the larger displacement responses than the actual behaviors for the curved bridge with larger subtended angles. Though many methods have been suggested to generate the inelastic demand spectrum for CSM, they might not give noticeable differences in inelastic displacement of the bridge pier.

• Tunnel and Underground Space
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• v.28 no.1
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• pp.59-71
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• 2018

Since the generalized Hoek-Brown (GHB) function predicts the strength of the jointed rock mass in a systematic manner by use of GSI index, it is widely used in rock engineering practices. In this study, a series of 2D elasto-plastic FE analysis, which adopts the GHB criterion as a yield function, was carried out to investigate the radial convergence characteristics of circular tunnel excavated in the GHB rock mass. The effect of the plastic potential function on the elasto-plastic displacement was also examined. In the analysis, the wide range of both the $K(={\sigma}_h/{\sigma}_v)$ and GSI values are considered. For each K value, the variation of the ratio of sidewall displacement to roof displacement was calculated with varying GSI values and the obtained displacement patterns were analysed. The calculation results show that the displacement ratio significantly depends not only on the K value but also on the range of GSI value. In particular, for lower range of GSI value, the displacement ratio pattern calculated in the elasto-plastic regime is opposite to that predicted by the elasticity theory. In addition, the variation of the radial displacement ratio with GSI value for different types of plastic potential function showed similar trend.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.2
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• pp.23-31
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• 2008

Dynamic earth pressure acting on geotechnical structures can be driving force or resisting force for the displacement of the structure according to the phase relation between the dynamic earth pressure and inertia force of structures. In this research, the evaluation procedure of the phase relation between the dynamic earth pressure and the inertia force was proposed. According to the procedure, numerical analyses on caisson foundation of bridges were performed and the phase relation was analyzed. The analysis results showed that the dynamic earth pressure becomes the driving force, which increases the displacement of the structure, if the displacement amplitude of ground is larger than that of structure due to the low stiffness of the ground, and the dynamic earth pressure becomes the resisting force against the displacement of the structure if the displacement amplitude of ground is smaller than that of structure due to the high stiffness of the ground.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.2
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• pp.135-140
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• 2010

A new treatment is proposed to handle a deflection limit in the open-loop-onset-point (OLOP), which is commonly used in the prediction of pilot in-the-loop oscillation (PIO) due to a rate saturation. The new approach is motivated by the frequency response of a stand-alone actuator in that, unlike the suggestion by the original OLOP procedure, the rate limit onset is not delayed to a higher frequency by a deflection limit. Indeed, if a feedback control loop is closed, the rate limit onset can be shifted to a lower frequency since the controller tends to react with larger commands when deflection limited. The amplitude of the command at this onset frequency is combined with the deflection limit to estimate the associated gain reduction in the open-loop-onset-point in the final step of the OLOP process. The comparison of the new approach with the previous method reveals that an inaccurate optimism which can occur in the previous method is corrected by the proposed treatment.