• Smart Structures and Systems
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• v.4 no.2
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• pp.261-278
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• 2008

The results of the application of shape memory alloy (SMA) prestressing devices on an aqueduct are presented in this paper. The aqueduct was built in 1747 to provide water to the city of Larnaca and to its port. Because of its importance to the cultural heritage of Cyprus, the aqueduct has been selected as one of the case-study monuments in the project Wide-Range Non-Intrusive devices toward Conservation of Historical Monuments in the Mediterranean Area (WIND-CHIME). The Department of Antiquities of Cyprus, acting in a pioneering way, have given their permission to apply the devices in order to investigate their effectiveness in providing protection to the monument against probable catastrophic effects of earthquake excitation. The dynamic characteristics of the structure were determined in two separate occasions and computational models were developed that matched very closely the dynamic characteristics of the structure. In this paper the experimental setup and the measured changes in the dynamic characteristics of the monument after the application of the SMA devices are described.

• Earthquakes and Structures
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• v.9 no.4
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• pp.719-733
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• 2015

Seismic risk management of the built environment is integrated by two main stages, the assessment and the remedial measures to attain its reduction, representing both stages a complex task. The seismic risk of a certain structure located in a seismic zone is determined by the conjunct of the seismic hazard and its structural vulnerability. The hazard level mainly depends on the proximity of the site to a seismic source. On the other hand, the ground shaking depends on the seismic source, geology and topography of the site, but definitely on the inherent earthquake characteristics. Seismic hazard characterization of a site under study is suggested to be estimated by a combination of studies with the history of earthquakes. In this Paper, the most important methods of seismic vulnerability evaluation of buildings and their application are described. The selection of the most suitable method depends on different factors such as number of buildings, importance, available data and aim of the study. These approaches are classified in empirical, analytical, experimental and hybrid. For obtaining more reliable results, it is recommends applying a hybrid approach, which consists of a combination between methods depending on the case. Finally, a recommended approach depending on the building importance and aim of the study is described.

• Smart Structures and Systems
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• v.4 no.2
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• pp.209-220
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• 2008

A methodology for the seismic vulnerability assessment of historical monuments is presented in this paper. The ongoing work has been conducted in Tunisia within the framework of the FP6 European Union project (WIND-CHIME) on the use of appropriate modern seismic protective systems in the conservation of Mediterranean historical buildings in earthquake-prone areas. The case study is the five-century-old Zaouia of Sidi Kassem Djilizi, located downtown Tunis, the capital of Tunisia. Ambient vibration tests were conducted on the case study using a number of force-balance accelerometers placed at selected locations. The Enhanced Frequency Domain Decomposition (EFDD) technique was applied to extract the dynamic characteristics of the monument. A 3-D finite element model was developed and updated to obtain reasonable correlation between experimental and numerical modal properties. The set of parameters selected for the updating consists of the modulus of elasticity in each wall element of the finite element model. Seismic vulnerability assessment of the case study was carried out via three-dimensional time-history dynamic analyses of the structure. Dynamic stresses were computed and damage was evaluated according to a masonry specific plane failure criterion. Statistics on the occurrence, location and type of failure provide a general view for the probable damage level and mode. Results indicate a high vulnerability that confirms the need for intervention and retrofit.

• Structural Engineering and Mechanics
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• v.86 no.4
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• pp.547-571
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• 2023

To deeply probe the actual earthquake level and fragility of typical reinforced concrete (RC) structures under multiple intensity grades, considering diachronic measurement building stock samples and actual observations of representative catastrophic earth shocks in China from 1990 to 2010, RC structures were divided into traditional RC structures (TRCs) and bottom reinforced concrete frame seismic wall masonry (BFM) structures, and the empirical damage characteristics and mechanisms were analysed. A great deal of statistics and induction were developed on the historical experience investigation data of 59 typical catastrophic earthquakes in 9 provinces of China. The database and fragility matrix prediction model were established with TRCs of 4,122.5284×104 m² and 5,844 buildings and BFMs of 5,872 buildings as empirical seismic damage samples. By employing the methods of structural damage probability and statistics, nonlinear prediction of seismic vulnerability, and numerical and applied functional analysis, the comparison matrix of actual fragility probability prediction of TRC and BFM in multiple intensity regions under the latest version of China's macrointensity standard was established. A novel nonlinear regression prediction model of seismic vulnerability was proposed, and prediction models considering the seismic damage ratio and transcendental probability parameters were constructed. The time-varying vulnerability comparative model of the sample database was developed according to the different periods of multiple earthquakes. The new calculation method of the average fragility prediction index (AFPI) matrix parameter model has been proposed to predict the seismic fragility of an areal RC structure.

• 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.

• Journal of architectural history
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• v.32 no.3
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• pp.63-76
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• 2023

Homogot Lighthouse is located in Pohang of the easternmost of Korean Peninsula. Homogot has become first known as Cape Clonard in the West through the navigation log by La Perouse, a Frenchman who embarked on a global exploration in 1785. Homogot Lighthouse represents an outstanding accomplishment of modernization that numerous civilized countries scrambled to attain in the early 20^th century. Located where the geographical risk of earthquakes is high, the structure was nonetheless built to be 26.4m high with brick masonry. Structurally safe and aesthetically graceful, it demonstrates neoclassical ideas superbly in terms of style as well. Although the history of Asian lighthouses is shorter than that of European ones. Homogot Lighthouse, which demonstrates the history of a modern lighthouse along with those in Japan and China, is differentiated by the following characteristics. ① The 'living lighthouse heritage' is linked to one of the largest lighthouse museum in the world. ② Where you can see the earliest sunrise at the easternmost of the Eurasian Continent. ③ The completion of a modern-style lighthouse constructed at the easternmost of the Far East after being initiated in Europe. ④ Differentiated historical, architectural, and aesthetic value. ⑤ The heart of the national marine park.

• Journal of Conservation Science
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• v.32 no.3
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• pp.425-436
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• 2016

The Yakhyeon catholic church (Historic Site No. 252 in Korea) that was constructed in 1892 has been the first western brick structure to ever have existed and one of the most important historical materials in the Korean modern architecture. After a fire had broken out at the catholic church in 1998, the stained glass on the back wall, the slab glass (dalle de verre) introduced by Lee Nam Guy in 1974, was repaired in 1999 because of singe scorch and water leakage. An analysis of the coloration elements showed that yellow, red and green included Zn, K and Cd, respectively. The glass of red contained Se, dark green contained Mn and Cr, and blue contained Pb and S. According to material analysis, the masonry joint was identified dolomite ($CaMg(CO_3)_2$) and calcite ($CaCO_3$), which was observed plate, columnar, rhombic and square of crystalline particles. Meanwhile, ultrasonic velocity in the stained glass recorded low speed in the middle and lower right of the window (an average of 4,130 m/s). And the joint was measured the lowest physical properties of the top left and middle of the window (an average of 2,053 m/s). This study have showed that extensive physical damage was founded to the left and middle rather than the right side. In this respect, more research in needed to conserve the correlation between color and physical properties.