• Journal of the Korean Institute of Rural Architecture
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• v.16 no.4
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• pp.59-66
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• 2014

This paper deals with vibration of plates with concentrated mass on elastic foundation. The object of investigating natural frequencies of tapered thick plate on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Free vibration analysis that tapered thick plate in this paper. Finite element analysis of rectangular plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on pasternak foundation. The Winkler parameter is varied with 10, $10^2$, $10^3$ and the shear foundation parameter is 5, 10. This paper is analyzed varying thickness by taper ratio. The taper ratio is applied as 0.0, 0.25, 0.5, 0.75, 1.0. And the Concentrated Mass is applied as P1, Pc, P2 respectively.

• Earthquakes and Structures
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• v.2 no.1
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• pp.25-42
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• 2011

This paper discusses a mechanical model for the vulnerability assessment of old masonry building aggregates that takes into account the uncertainties inherent to the building parameters, to the seismic demand and to the model error. The structural capacity is represented as an analytical function of a selected number of geometrical and mechanical parameters. Applying a suitable procedure for the uncertainty propagation, the statistical moments of the capacity curve are obtained as a function of the statistical moments of the input parameters, showing the role of each one in the overall capacity definition. The seismic demand is represented by response spectra; vulnerability analysis is carried out with respect to a certain number of random limit states. Fragility curves are derived taking into account the uncertainties of each quantity involved.

• Structural Engineering and Mechanics
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• v.84 no.4
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• pp.479-488
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• 2022

Aiming to examine different failure patterns in multistory URM walls, two 1/3 scaled three-story and three-bay URM models were designed for the quasi-static loading tests to contrastively investigate the failure processes and characteristics of the multistory URM walls. Two different failure responses were observed with special attention paid to the behavior of spandrel-failure mode. By evaluating the seismic performance and deformation behavior of two test walls, it is demonstrated that spandrels, that haven't been properly designed in some codes, are of great significance in the failure of entire URM walls. Additionally, compared with pier-failure mode, spandrel-failure for multistory URM building is more reasonable and advisable as its effectively participation in energy dissipation and its efficiently improvement on seismic capacity and deformation in the overall structure. Furthermore, the experimental results are beneficial to improve seismic design and optimize reinforcement method of URM buildings.

• Earthquakes and Structures
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• v.26 no.3
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• pp.191-201
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• 2024

A comprehensive probabilistic seismic hazard analysis was carried out in Istanbul to examine the seismotectonic features of the region. The results showed that earthquakes can trigger one another, resulting in the grouping of earthquakes in both time and space. The hazard analysis utilized the Poisson model and a conventional integration technique to generate the hazard curve, which shows the likelihood of ground motion surpassing specific values over a given period. Additionally, the study evaluated the impact of seismic hazard on the structural integrity of an existing masonry tower by simulating its seismic response under different ground motion intensities. The study's results emphasize the importance of considering the seismotectonic characteristics of an area when assessing seismic hazard and the structural performance of buildings in seismic-prone regions.

• International Journal of High-Rise Buildings
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• v.9 no.1
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• pp.17-41
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• 2020

In Part One, I documented the evolution of the use of the elevator and the iron frame to build ever-taller buildings that would eventually be called "skyscrapers," to offset the ever-increasing cost of Manhattan real estate. By the start of the Great Depression of the 1870s in 1873, New York architects had erected two ten-storied skyscrapers. In Part Two I document the major events, designers, and buildings in New York, Chicago, and other American cities that eventually culminated in the ability to erect 20 story skyscrapers by 1890.

• Earthquakes and Structures
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• v.9 no.4
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• pp.789-830
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• 2015

The recent re-assessment of the seismic hazard in Europe led for many regions of low to moderate seismicity to an increase in the seismic demand. As a consequence, several modern unreinforced masonry (URM) buildings, constructed with reinforced concrete (RC) slabs that provide an efficient rigid diaphragm action, no longer satisfy the seismic design check and have been retrofitted by adding or replacing URM walls with RC walls. Of late, also several new construction projects have been conceived directly as buildings with both RC and URM walls. Despite the widespread use of such construction technique, very little is known about the seismic behaviour of mixed RC-URM wall structures and codes do not provide adequate support to designers. The aim of the paper is therefore to propose a displacement-based design methodology for the design of mixed RC-URM edifices and the retrofit of URM buildings by replacing or adding selected URM walls with RC ones. The article describes also two tools developed for estimating important quantities relevant for the displacement-based design of structures with both RC and URM walls. The tools are (i) a mechanical model based on the shear-flexure interaction between URM and RC walls and (ii) an elastic model for estimating the contribution of the RC slabs to the overturning moment capacity of the system. In the last part of the article the proposed design method is verified through nonlinear dynamic analyses of several case studies. These results show that the proposed design approach has the ability of controlling the displacement profile of the designed structures, avoiding concentration of deformations in one single storey, a typical feature of URM wall structures.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.113-121
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• 2015

Building using masonry accounts for most of the smaller houses in Korea but due to brittle behavior and low ductility the frequency of usage has decreased in recent years. Despite this, this form of building has been gaining attention overseas for its low cost in construction and environment-friendliness of the materials. As such, many studies are being conducted to resolve the disadvantages in structure. This study produced an specimen for masonry-filled wall and the intersection to confirm the difference in structural movement depends on the existence or lack of expansion joint and verified the reinforcement effect from inserting a connecting steel item (steel plate, stainless steel twist bar). The experiment results show that the specimen with a steel plate inserted saw an increase in durability and an improvement in the strength of the specimens, while the specimen that had stainless steel twists bar inserted saw an increase in ductility that did not cause brittle failure, indicating that the reinforcement effects of inserting a connecting steel item are effective.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.4
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• pp.59-66
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• 2022

This study is to investigate the old buildings that have been built more than 50 years ago, targeting the areas of Seongan and Jungang-dong, the historic urban area of Cheongju. Their types and distribution characteristics are as follows. 1) First, the old buildings existing in downtown Cheongju account for 21.4% of 1,070 out of the total 5,000 buildings. Among them, wooden buildings before the 1950s accounted for 60% of them, resulting in severe aging. 2) Second, by use, 728 detached houses and 276 neighborhood living facilities account for 93.8% of the total, with 16 offices and 12 religious facilities. By structure, there are wood 65%, masonry 30%, and reinforced concrete 5% (54 buildings). By number of floors, the first floor 90%, the second floor 7.3%, and the third floor or higher 2.7% (30 buildings). The roof material is 51.6% of earthenware, followed by slate, cement, and slab. 3) Third, the old buildings are scattered all over the streets, and are concentrated in Namju-dong, Nammun-ro 1-ga-dong, Seoun-dong, and Sudong at the foot of Uamsan Mountain, a former refugee village. Also old buildings are distributed in Seoun-dong and Seokgyo-dong where hanok(korean traditional houses) are concentrated, in Namju and Nammunro 1 ga-dong blocks connected by alleys, and in cul-de-sac all over the place.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.1
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• pp.37-44
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• 2011

The maintenance works for brick-structured buildings are a new field in Korea, and practical cases are yet inadequate so that such works may cause adverse effects of damaging the buildings after all. Therefore, this study has extracted a preservation technology believed to be most desirable in minimizing the damage to the original state of the buildings and preserving the value as the cultural assets through maintenance work details from 1986 to 2010 regarding brick-structured buildings designated as cultural properties. Firstly, a brick replacement method of using the brick used at the time of construction is efficient in replacement and repair of brick material for preserving value of cultural assets and minimizing damage of the original form. Secondly, use of lime mortar through material analysis is effective in repair of masonry joint and mortar but it is not used often due to high experimental cost. Finally, reinforcement of structure using a form for a building with severe damage is most efficient when considering additional problems. However, damage on the original form of a building can be minimized and value of a building can be preserved only when consideration on sufficient case analysis, materials to be used, and conditions of a building is supported.

• Architectural research
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• v.2 no.1
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• pp.1-6
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• 2000

Ever since Viollet-le-Due began to examine Gothic structural elements using his method of geometrical analysis in the nineteenth century, art and architectural historians and a few engineers have periodically attempted to ascertain the structural advantages of the various characteristic features of Gothic architecture. In none of these studies, however, has the way forces work within the lightweight and spacious masonry Gothic buildings been precisely interpreted. The approach taken by art and architectural historians has therefore tended to be primarily descriptive and to be based on intuitive assumptions. This study intend to analyze the Gothic non-vaulted nef unique(aisleless) structures of Lower Languedoc which has never been scientifically tested, and to provide as comprehensive an explanation as possible of the way in which these non-vaulted buildings work. In order to achieve this goal, this paper Is to examine, by means of finite element analysis. the links between the width of non-vaulted aisleless structures, the configuration of the arches, diaphragm arch, and the buttress. Finite element analysis with a computer provides a more accurate analysis than the methods of analysis that have been heretofore applied to Gothic structures, as well as permits us to visualize the global stress behavior of the structure. Combined with traditional methods of studying historical buildings, therefore, finite element analysis inevitably give us a broader understanding of the processes involved in the design and construction of medieval buildings.