• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.1-12
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• 2019

The purpose of this study is to enhance the seismic performance of exposed column-base plate weak-axis connections for small-sized steel buildings. According to the site inspection for the small-sized building construction, the arbitrary connection details in steel buildings have been applied at the job site, which is considered to be insufficient to guarantee structural safety and stability considering the increased seismic risk in Korea. Therefore, a series of test programs had been done to develop enhanced connection details in order to ensue the adequate seismic stability and safety of small-sized steel buildings. From the test results, It was found that the exposed column-base plate weak-axis connections commonly used in Korea shows very poor seismic behavior due to the "Rocking" phenomena caused by the residual plastic deformation of anchor bolts between anchor plate and concrete. A series of hysteretic tests for finding that solution were conducted to reduce the "Rocking" phenomena of the column-base plate connections, and local buckling of webs in H-column. Finally the enhanced stable seismic behavior was obtained by reinforcing at least 8 anchor bolts with good bonding strength and stiffeners to the webs in H-column.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.46-49
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• 2006

In general, the shear behavior mode of URM wall expresses four types of modes such as rocking failure, sliding shear failure, toe crushing failure, and diagonal tension failure. From the comparison of each equation according to the shear behavior modes, the failure modes based on the aspect ratio and vertical axial stress can be expected. The objectives of this study is to find out the shear behavior of URM wall with different aspect ratio. The test results show that the aspect ratio is understood as an important variable.

• Earthquakes and Structures
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• v.20 no.1
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• pp.71-86
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• 2021

This paper focuses on the development and assessment of the expected damage for the rocking response of rigid anchored blocks, with irregular geometry and non-uniform mass distribution, considering the site conditions and the seismicity of Mexico City. The non-linear behavior of the restrainers is incorporated to evaluate the pure tension and tension-shear failure mechanisms. A probabilistic framework is performed covering a wide range of block sizes, slenderness ratios and eccentricities using physics-based ground motion simulation. In order to incorporate the uncertainties related to the propagation of far-field earthquakes with a significant contribution to the seismic hazard at study sites, it was simulated a set of scenarios using a stochastic summation methods of small-earthquakes records, considered as Empirical Green's Function (EGFs). As Engineering Demand Parameter (EDP), the absolute value of the maximum block rotation normalized by the body slenderness, as a function of the peak ground acceleration (PGA) is adopted. The results show that anchorages are more efficient for blocks with slenderness ratio between two and three, while slenderness above four provide a better stability when they are not restrained. Besides, there is a range of peak intensities where anchored blocks located in soft soils are less vulnerable with respect to those located in firm soils. The procedure used in here allows to take decisions about risk, reliability and resilience assessment of different types of contents, and it is easily adaptable to other seismic environments.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.04a
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• pp.298-307
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• 2000

The behavior of a unreinforced cement brick building structure subjected to earthquake loading was experimentally investigated. for this four full size wall specimens were tested under quasi-static in-plane cyclic loading. Experimental observations indicate that the failure modes of unreinforced masonry walls are principally governed by sliding or/and rocking depending on the aspect ration and magnitude of axial loading. Also found was the flexure or shear mode resulting from the degraded strength of brick and/or mortar due to the cyclic loading effect.

• Journal of English Language & Literature
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• v.54 no.4
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• pp.443-459
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• 2008

This paper examines the discourse of masturbation in modern England and aims to re-draw the map of male sexuality related to such issues as nation, empire, family, and economy. It argues that the discourse of masturbation in modern England reflects national anxieties for the future of empire and an economic concern for unproductive sexual behavior, which were the main factors to transform masturbation into "solitary vice." The anxieties about empire and British dominance were constituted as the core of the anti-masturbation discourse on the boys. The imperial destiny was regarded to depend on the protection of the middle- and upper-class boys from the harmful psychological and physiological effects of masturbation represented in Lawrence's "The Rocking-Horse Winner." In the case of a single male, the concern for masturbation is constructed as a concern about economy, family, and human solidarity. As seen in Eliot's Silas Marner, the act of masturbation was condemned as the fulfillment of illegitimate sexual desire outside the familial sphere and a commercial economy, and thus without the possibility of human community. Silas Marner and Meredith's The Ordeal of Richard Feverel show the ways of reconstituting sexual others as normalized subjects: Boys were forced to be asexual through the regime of surveillance; and a single male was required to enroll in a remedial course on familial respectability.

• Geomechanics and Engineering
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• v.4 no.3
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• pp.173-190
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• 2012

With recent growing interests in the Performance-Based Seismic Design and Assessment Methodology, more realistic modeling of a structural system is deemed essential in analyzing, designing, and evaluating both newly constructed and existing buildings under seismic events. Consequently, a shallow foundation element becomes an essential constituent in the implementation of this seismic design and assessment methodology. In this paper, a contact interface fiber section element is presented for use in modeling soil-shallow foundation systems. The assumption of a rigid footing on a Winkler-based soil rests simply on the Euler-Bernoulli's hypothesis on sectional kinematics. Fiber section discretization is employed to represent the contact interface sectional response. The hyperbolic function provides an adequate means of representing the stress-deformation behavior of each soil fiber. The element is simple but efficient in representing salient features of the soil-shallow foundation system (sliding, settling, and rocking). Two experimental results from centrifuge-scale and full-scale cyclic loading tests on shallow foundations are used to illustrate the model characteristics and verify the accuracy of the model. Based on this comprehensive model validation, it is observed that the model performs quite satisfactorily. It resembles reasonably well the experimental results in terms of moment, shear, settlement, and rotation demands. The hysteretic behavior of moment-rotation responses and the rotation-settlement feature are also captured well by the model.

• Structural Engineering and Mechanics
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• v.60 no.4
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• pp.633-653
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• 2016

One of the major threats to the stability of classical columns and colonnades are earthquakes. The behavior of columns under high seismic excitation loads is non-linear and complex since rocking, wobbling and sliding failure modes can occur. Therefore, three dimensional simulation approaches are essential to investigate the in-plane and out-of-plane response of such structures during harmonic and seismic loading excitations. Using a software based on the Distinct Element Method (DEM) of analysis, a three dimensional numerical study has been performed to investigate the parameters affecting the seismic behaviour of colonnades' structural systems. A typical section of the two-storey colonnade of the Forum in Pompeii has been modelled and studied parametrically, in order to identify the main factors affecting the stability and to improve our understanding of the earthquake behaviour of such structures. The model is then used to compare the results between 2D and 3D simulations emphasizing the different response for the selected earthquake records. From the results analysis, it was found that the high-frequency motion requires large base acceleration amplitude to lead to the collapse of the colonnade in a shear-slip mode between the drums. However, low-frequency harmonic excitations are more prominent to cause structural collapse of the two-storey colonnade than the high-frequency ones with predominant rocking failure mode. Finally, the 2D analysis found to be unconservative since underestimates the displacement demands of the colonnade system when compared with the 3D analysis.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.448-454
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• 2000

Piled multi-block system has been frequently adopted in the historic structures or monuments of cultural heritage. It is well known that such a structural system is very vulnerable to the earthquake shaking. If the structure is of slender type, then it may experience overturning at very low level intensity of ground shaking. One of the methods used to protect such structures from earthquake is seismic isolation system. But the behavior of multi-block systems mounted on the isolated basis is not well understood yet. In this paper we investigate the dynamic behavior of single slender rigid block mounted on the three different isolation systems, i.e., P-F system, FPS and LRB system. Sliding at the isolation interface of P-F system and FPS is formulated based on Coulomb friction. The mounted single block is assumed undergoing rocking or sticking only. Impacting of a single block is described using distinct element method (DEM). Free vibrations due to a prescribed initial conditions are studied. Responses to the harmonic excitation and earthquake motions are calculated

• Geomechanics and Engineering
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• v.34 no.6
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• pp.649-664
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• 2023

Structural inertial interaction is a representative the effect of dynamic soil-foundation-structure interaction (SFSI), which leads to a relative displacement between soil and foundation, period lengthening, and damping increasing phenomena. However, for a system with a significantly heavy foundation, the dynamic inertia of the foundation influences and interacts with the structural seismic response. The structure-to-foundation mass ratio (MR) quantifies the distribution of mass between the structure and foundation for a structure on a shallow foundation. Although both systems exhibit the same vertical factor of safety (FS_v), the MR and corresponding seismic responses attributed to the structure and foundation masses may differ. This study explored the influence of MR on the permanent deformation and seismic response of soil-foundation-structure system considering SFSI via numerical simulations. Given that numerous dimensionless parameters of SFSI described its influence on the structural seismic response, the parameters, except for MR and FS_v, were fixed for the sensitivity analysis. The results demonstrated that the foundation inertia of heavier foundations induced more settlement due to sliding behavior of heavily-loaded systems. Moreover, the structural inertia of heavier structures evidently exhibited foundation rocking behavior, which results in a more elongated natural period of the structure for lightly-loaded systems.

• Korean Journal of Materials Research
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• v.4 no.1
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• pp.90-96
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• 1994

ZnO thin films were deposited using Diethylzinc and $N_{2}O$ gas by plasma enhanced CVD (PECVD) at low substrate temperatures below $300^{\circ}C$. The effect of deposition parameters on the growth rate and the structural properties was determined at various deposition conditions. Crystallized ZnO thin films were successfully deposited even at $150^{\circ}C$ of substrate temperature. Above $200^{\circ}C$ c-axis oriented ZnO thin films, of which a standard deviation of X-ray rocking curve was less than $6^{\circ}$. were deposited on glass substrates. The variation of deposition rate showed different trends depending on substrate temperature and rf-input power. According to the deposition rate behavior as a function of substrate temperature, the transition points were observed resulting from crystallization of ZnO thin films. The activation energies for the deposition of ZnO thin films were 3.1KJ/mol and 1.9KJ/mol for the rf powers of 200W and 250W, respectively.