• Journal of Korean Association for Spatial Structures
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• v.20 no.2
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• pp.95-104
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• 2020

Phaya-Thon-Zu temple has a unique architectural style connected by the three temples, and cultural values are highly as murals remain on some of the walls. However, various damages in internal walls and vaults have occurred due to earthquake and environmental influences. In order to analyze these damages, accurate structural analysis is required, but structural modeling is difficult, because Phaya-Thon-Zu temple is the complex masonry structure which is stacked with small bricks. Therefore, this study intends to analyze the causes of damages by examining collapse mechanism for cross section and longitudinal section of vaults in the entrance hall and shrine by using thrust line analysis, which is a geometric method, and to compare it with the actual damage situation.

• Journal of Korean Association for Spatial Structures
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• v.16 no.3
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• pp.67-78
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• 2016

Determining of the shape in the process of design for natural draught cooling tower is very important, because the shape of hyperbolic shell is respond sensitively to dynamic behavior of the whole cooling tower against wind load. In engineering practice, the geometric parameters have been determining based on the natural frequency. This study analyses influence of the tower shell geometric parameters on the structural behavior. For three representative models were selected, they were analyzed based on evaluation of damage by means of nonlinear FE-method. As a result, a hyperbolic rotational shell with the small radius overall was the lowest damage index induced by sufficient capacity of the stress redistribution and thus a wind-insensitive structure.

• Structural Engineering and Mechanics
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• v.24 no.1
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• pp.91-105
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• 2006

In this paper, post-earthquake capacity evaluation method of reinforced concrete buildings was studied. Substructure pseudo-dynamic test and static loading test of first story column in a four-story R/C building was carried out in order to investigate the validity of the evaluation method proposed in the Damage Assessment Guideline (JBDPA 2001). In pseudo-dynamic test, different levels of damage were induced in the specimens by pre-loading, and input levels of seismic motion, at which the specimens reached to the ultimate stage, were examined. From the experimental result, no significant difference in damage levels such as residual crack width between the specimens under static and pseudo-dynamic loading was found. It is shown that the seismic capacity reduction factors ${\eta}$ can provide a reasonable estimation of post-earthquake seismic capacity of R/C buildings suffered earthquakes.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.6
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• pp.93-100
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• 2019

Modern society is transforming into an extreme climate environment. This is fatal to humans and ecosystems and is expected to cause large-scale damage. As this spokesman, natural disasters are increasing as this global average temperature rises. Social and economic damage by this tendency is also increasing. In addition, the frequency and scale of social disasters are increasing. Damage to the living area due to the damage of the infrastructure due to the increased reliance on infrastructure has been increasingly enlarged. In this research, various disasters such as natural disasters and social disasters analyze the impact on urban safety. A local autonomous entity K Priority Management Establish a kind of disaster, prepare crisis management manual, and use it as a basic material of education / training.

• Earthquakes and Structures
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• v.22 no.3
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• pp.305-318
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• 2022

This paper presents a comparative study of the damage potentials for the 2016 Gyeongju and 2017 Pohang earthquakes in Korea. Plausible technical explanations are provided for the more severe damage observed in the 2017 Pohang earthquake in spite of its relatively weaker magnitude and intensity measures based on the response analysis of elastic and inelastic single-degree-of-freedom systems for the recorded ground motions. In addition, a detailed case study was conducted for a fatally damaged piloti building with an eccentric shear wall core based on nonlinear dynamic analysis using the input ground motions modified for the building site.

• Smart Structures and Systems
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• v.9 no.3
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• pp.253-271
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• 2012

Finite element (FE) model updating is a useful tool for global damage detection technique, which identifies the damage of the structure using measured vibration data. This paper presents the application of a finite element model updating method to detect the damage of a small-scale reinforced concrete building structure using measured acceleration data from shaking table tests. An iterative FE model updating strategy using the least-squares solution based on sensitivity of frequency response functions and natural frequencies was provided. In addition, a side constraint to mitigate numerical difficulties associated with ill-conditioning was described. The test structure was subjected to six El Centro 1942 ground motion histories with different Peak Ground Accelerations (PGA) ranging from 0.06 g to 0.5 g, and analytical models corresponding to each stage of the shaking were obtained using the model updating method. Flexural stiffness values of the structural members were chosen as the updating parameters. In model updating at each stage of shaking, the initial values of the parameter were set to those obtained from the previous stage. Severity of damage at each stage of shaking was determined from the change of the updated stiffness values. Results indicated that larger reductions in stiffness values occurred at the slab members than at the wall members, and this was consistent with the observed damage pattern of the test structure.

• Journal of architectural history
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• v.22 no.6
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• pp.47-58
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• 2013

The purpose of this study is to analyze the cause of damage to the three storied stone pagoda of Bulguksa temple in GyeongJu. This report is attempted to making reinforcement and conservation plan through investigating and analyzing the cause of damage to that. The damage is caused by occurring of stress, degrading of stone strength, changing of underground soil structure, natural disasters and so on. Compressive stress, shear stress, bending stress and lateral pressure affected to the pagoda since built up. Ultrasonic examination data tells the strength of the stone. According to this result, strength of the stereobate stone materials is enough to support the weight of the upper ones. But we could found many other factors of the damage could consider, for example the problems occurred on building the pagoda construction and the weakness of the stone material(soft rock). And many environmental factors being changed in soil structure(subsidence of soil and degradation of bearing power of soil and freezing and melting of soil) can be seen as the cause of the damage. Natural disasters like earthquake, lightning and heavy rain were also thought to give direct impact to the damage. At last Concentration of compressive stress caused the crack and exfoliation on the stone materials and shear stress, bending stress and lateral pressure were main causes of the stereobate stone materials shearing.

• Earthquakes and Structures
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• v.7 no.5
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• pp.609-626
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• 2014

The capabilities of a high-resolution Digital Image Correlation (DIC) system are presented within the context of deformation measurements of full-scale concrete columns tested under reversed cyclic loading. The system was developed to have very high-resolution such that material strains on the order of the cracking stain of concrete could be measured on the surface of full-scale structural members. The high-resolution DIC system allows the measurement of a wide range of deformations and strains that could only be inferred or assumed previously. The DIC system is able to resolve the full profiles of member curvatures, rotations, plasticity spread, shear deformations, and bar-slip induced rotations. The system allows for automatic and objective measurement of crack widths and other damage indices that are indicative of cumulated damage and required repair time and cost. DIC damage measures contrast prevailing proxy damage indices based on member force-deformation data and subjective damage measures obtained using visual inspection. Data derived from high-resolution DIC systems is shown to be of great use in advancing the state of behavioral knowledge, calibrating behavioral and analytical models, and improving simulation accuracy.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.11a
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• pp.93-96
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• 2007

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.4
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• pp.235-244
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• 2018

The main function of the general hospital building is to provide medical facilities and service. However, damage to the non-structural elements such as architectural, medical, mechanical and other components will interrupt those functions after the earthquake. Especially, it is considered that, damage to the non-structural elements is a serious event because it is directly associated with the lives of patients. Therefore, this study evaluated whether the certain non-structural elements of general hospital building has the seismic performance to provide hospital medical services after the earthquake. The evaluation is conducted by selecting the non-structural elements used in general hospital which are sensitive to acceleration, such as cooling towers, air handler, MRI and CT. As a result, the non-structural elements located on the upper floor without suitable support method did not meet the performance objective. Therefore, adequate anchorage against the seismic event is required for such non-structural elements that are acceleration-sensitives.