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Nemrut Dağ Tumulus and Monuments, constructed during the Commagenian Kingdom approximately 2000 years ago on the peak of Mount Nemrut, is a UNESCO World Heritage Site in Turkey. The region is about 5 km away from the East Anatolian Fault, therefore, this paper focuses on dynamic testing and earthquake simulations carried out within the framework of...
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Context 1
... earthquakes correlate with the internationally accepted response spectrum curves (Fig. 3). The results show that (Table 1) Kobe earthquake causes the head to fall. Erzincan, Gölcük and Lan- ders earthquakes result in a few centimeters of openings between stone blocks. ...
Context 2
... Düzce ×2 earthquake, the head falls and openings are formed between blocks. Finally, after Düzce ×3 earthquake, the monument collapses completely (Table 1). The results indicate that the monu- ments perform generally well for major earthquake records, receive minor damage when the records are multiplied by two, and major damage when records are tripled in amplitude. ...
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Citations
... Finite element analysis is widely accepted as an effective method for the structural evaluation or restoration of historical buildings [14][15][16][17][18][19][20][21][22][23][24][25][26]. It is one of the most important modeling methods whose use in the structural analysis process has become more frequent with the development of technology. ...
Finite element method (FEM) provides the numerically solving differential equations arising in engineering and mathematical modeling of physical systems. This process begins by determining the assignment of a theoretical node. A node is a single point on a frame, shell, or solid element and each element can be programmed with its location's material and structural data. Programming with the FEM is quite time-consuming for complex geometry such as historical buildings. This study aims to examine a low-cost and time-saving technology to build a FEM model using photogrammetry. In accordance with this aim, classical modeling techniques and photogrammetric modeling techniques were discussed. The results demonstrated that similar values were revealed in stress and deformation values. Consequently, the study emphasizes the potential of photogrammetry technology as an integrated approach for bringing together the disciplines of architecture and engineering that usually require two distinct expertise in analysing the structural behavior of historical buildings.
... This "System Identification" process requires different setups for cross-correlation during the signal processing of the captured vibrations. In optimal conditions, the instrumentation is positioned either inside the building [6,27,28] or at the exterior of the monument [1,29,30]. ...
Historic Cairo has been a UNESCO World Heritage Site since 1979. It has more than
600 historic structures, which require extensive studies to sustain their cultural, religious, and economic values. The main aim of this paper is to undertake dynamic investigation tests for the dome of Fatima Khatun, a historic mausoleum in Historic Cairo dating back to the 13th century and consisting of mainly bricks and stones. The challenge was that the structure was difficult to access, and only a small portion of the top was accessible for the attachment of accelerometers. Current dynamic identification procedures typically adopt methods in which the sensors are arranged at optimal locations and permit direct assessment of the natural frequencies, mode shapes, and damping ratios of a structure. Approaches that allow for the evaluation of dynamic response for structures with limited accessibility are lacking. To this end, in addition to in situ dynamic investigation tests, a numerical
model was created based on available architectural, structural, and material documentation to obtain detailed insight into the dominant modes of vibration. The free vibration analysis of the numerical model identified the dynamic properties of the structure using reasonable assumptions on boundary conditions. System identification, which was carried out using in situ dynamic investigation tests
and input from modelling, captured three experimental natural frequencies of the structure with their mode shapes and damping ratios. The approach proposed in this study informs and directs structural restoration for the mausoleum and can be used for other heritage structures located in congested historic sites.
... This issue becomes even more important when tunnels were constructed adjacent of historic monuments. Afifipour et al. [1], Azadi [2], Sevim et al. [3], Russo [4] and Didem Aktas & Turer [5] researched on effect of seismic waves of historic monument. In their studies, the effect of scattering around the tunnels was not considered. ...
... where [17] researched the dynamics behavior of scattering phenomena with Fourier's series. The scatter waves in the cylindrical cavity are expressed based on Eq. (5). ...
During the recent earthquake, a lot of damage was reported from the historical monuments in the adjacent twin tunnels. While scientific research shows, the vulnerability of other monuments is much less than the monuments adjacent twin tunnels. The first type of Hankel function was used to study scattering waves in time domain analysis. The time domain results were transferred to the frequency domain using Fourier transform criteria. Extra stress concentrations were calculated based on the results of frequency domain analysis and developed a new approach to scattering. Arg-Karim Khani citadel and twin subway tunnels in Shiraz were selected as a case study. Three near-field earthquakes to perform the time history analysis were considered. The statistical difference based on Mann–Whitney test illustrates the seismic behavior of monument with and without considering twin tunnels, which shows that there is significant difference between them. The mean of P value amount of this comparison in horizontal and vertical direction is 0.005 and 0.016, respectively (P value < 0.05). The integrated analysis shows the importance of frequencies in creating different scattering around twin tunnels, which depends on the distance tunnels, the diameter of the tunnels, the soil characteristics, the seismic wave types, etc.
... In order to some important researches are given without regarding scattering waves. [16][17][18][19][20] An analytical solution for the dynamic stress concentration of circular twin tunnels presented against vertical and shear waves in a filled space using derivatives of complex variables. The results illustrated the main effect on the dynamic response of the walls of the tunnel. ...
Stress concentration around twin tunnels and its impact on monuments have been receiving much attention by researchers. To investigate the effect of scattering in twin tunnels, Hankel function of the first kind has been used by various researchers. The mathematical relation of Fourier expansion was modified and the time-domain analysis was transformed to frequency-domain analysis to provide a novel method for analyzing stress concentration factor. The combined finite element scattering model (FESCAM) was designed and developed in MATLAB. Analysis was performed in the presence of twin tunnels with scattering of P wave and in the absence of twin tunnels under the effect of near-field earthquake. According to the results, dynamic stress concentration factor (DSCF) for Kobe earthquake P-wave with different wave angles and maximum frequency showed maximum scattering at α=0° and θ=0° in the tunnel. In addition to increased stress concentration factor, the results of Mann-Whitney statistical test in SPSS revealed a significant difference between the seismic performance of Arg-e Karim Khani and Zand underpass in the presence and absence of the tunnel (P Value<0.05). A scattering effect of less than 10% was calculated taking into account the combined effect of the calculated seismic waves using incremental extended finite element software. Scattering depends on frequency, and higher scattering was reported for higher frequencies.
... Different methodologies for the structural restoration of historical buildings are described [12][13][14][15]. e acquired experience on the analysis and strengthening of numerous buildings in Italy after the recent earthquakes were also useful for this study [16][17][18][19][20]. e interdisciplinary study [21], the nondestructive tests, and the tests performed on the shake table [22][23][24] were also used in the analysis of the damages and the strengthening for complex masonry buildings. Also, different studies about structural analysis of historical building along with their numerical modelling are reported [25][26][27][28][29]. ...
Firstly, some important aspects of the restoration and structural strengthening of historical masonry buildings are briefly discussed. Particularly, as an illustration of the appropriate approach to solving such an issue, an example of the restoration of the Minceta fortress in Dubrovnik has been described. Based on the results of the extensive field and laboratory works with defined damages and cracking state in the fortress, as well as located sliding surfaces in foundation rock near deep excavation, the static and dynamic analysis of stress-strain states and safety was performed at the characteristic time point in the history of the fortress. Different geometry models for discretization of the fortress and the foundation rock, as well as different constitutive models for masonry and rock, were considered. Based on the results of the case study, the solutions were proposed for the strengthening of the foundation rock, as well as for the restoration and the limited allowed strengthening of the fortress. It is believed that this study may be helpful in the restoration and strengthening of similar historical masonry structures.
... To evaluate the structural response of historical masonry monuments, both numerical and experimental research have been conducted. Finite element analysis is widely recognized as an effective method for the structural assessment or restoration of old structures [20][21][22][23][24][25][26]. In particular, static and dynamic numerical finite element analysis is commonly used to assess the structural response of masonry structures. ...
... Ideally, experimental and numerical results can be combined in order to verify the structural performance of monuments. In particular, results obtained from eigenmode finite element analysis, such as natural frequencies and shape modes, can be compared with experimental research, in order to verify the validity of the material properties and other assumptions considered in the model [21,54]. ...
In this article an overall procedure is proposed, for the numerical investigation of the structural response of ancient monuments made of megalithic stones. The procedure is implemented on the middle temple of the Mnajdra Megalithic structure, listed as UNESCO World Heritage and regarded as one of the oldest structures from early civilization dating back to about the 4th millennium BC. First, the geometry of the structure is obtained from a point cloud using terrestrial laser scanning. To investigate and estimate the material properties of the structural system, parametric eigenvalue analysis is conducted using the finite element method and results are compared with experimental data from ambient vibration sensors applied to the same structure. The structural response of the system is then evaluated, using nonlinear finite element analysis. Variation of unilateral, frictional contact conditions between megaliths in a preceding analysis step may influence the eigenvalue analysis which follows, indicating the importance of the proper consideration of contact conditions, on the response of the structure. An old collapse in a part of the structure is also reproduced by the numerical model. The proposed scheme, which combines numerical analysis and experimental vibration output to derive structural properties of the monument, can be used in similar structural systems, consisting of multi-body megalithic stones.
... As mentioned above, many researchers have studied the seismic behavior of monument and historic structures without considering the effect of scattering such as subway tunneles. The most important researches in this field were done without considering scattering waves (Afifipour et al., 2011;Azadi and Zahedi, 2011;Sevim et al., 2011;Russo, 2013;Didem Aktas and Turer, 2015). Previous researches have not been considered the scattering of actual seismic waves. ...
The frequent failure of newly built tunnels under earthquake loading has led to a broader range of research into assessing the effect of seismic waves on tunnels. Numerous researchers have worked on twin tunnels and the effect of wave scattering due to vibration of harmonic waves to date. As for the near-field wave scattering and range of the recording of the acceleration of the ground during an earthquake. However, little research has been conducted on a comprehensive scale. This study attempted to examine the scattering in Si-o-seh Pol Bridge, a monument in Isfahan city, using the Hankel’s function of the first and second kinds for near-field earthquakes (Northridge, Tabas and Kobe). All of scattering analysis were done through FESCAM code that designed and developed in MATLAB software as a toolbox by authors of this paper. The historic bridge of Si-o-seh Pol Bridge and its neighboring twin tunnels for subway were selected as a case study. The first kind of Hankel’s function was considered as a supplementary parameter to the seismic analysis using finite element method procedure. The amount of dynamic scattering of twin tunnels subjected seismic loads considered as extra strain and stress around tunnels using Hankel’s function results. The results between two cases with and without considering scattering waves of tunnels show that the mean horizontal displacement and the mean vertical displacement of Si-o-seh Pol Bridge can be increased about 28.8% and 30.11% respectively. The results of statistical analysis with Mann-Whitney test show that there is no significant difference between the seismic performance of Si-o-seh Pol Bridge with and without consideration of the scattering effect of the tunnels (P-Value = 0.6 > 0.05). However, the results of this study versus the past studies reflect the fact that horizontal and vertical displacements when involving the tunnel are 34.10% increase and −48.51% decline, respectively. This means that the twin tunnels are effective in displacement of the adjacent monument from the engineering perspective.
... They further studied the effect of rigid restraint systems through dynamic finite element analyses. Most recently, Aktaş and Turer incorporated modal analysis and system identification of the large freestanding Nemrut monuments in Turkey [7]. The determined modal frequencies were used to calibrate a detailed finite element model, which was subsequently used to assess the monuments' vulnerability and guide seismic mitigation strategies. ...
The seismic protection of cultural heritage, particularly statues, is a critical issue due to its high cultural significance, difficulty to repair or replace artifacts, and observed poor behavior during past earthquakes. Recent research has explored analysis techniques and methodologies for predicting the seismic response of statues; however, these studies typically assume the statue to be either freestanding or rigidly attached. The seismic response of statues with these different boundary conditions varies widely and therefore accurate characterization is critical. While modern mounting techniques aim to rigidly attach a statue to the floor or to a pedestal, the degree of rigidity of the as-built system may vary greatly, particularly for large and heavy statues, which are difficult to mount. To this end, experimental modal analysis and system identification were conducted on six statues while in their installed condition at the Asian Art Museum in San Francisco, California. The tested statues were large, typically stone, and restrained with different mechanisms for comparison. The statue-pedestal-restraint systems were observed to be quite flexible with natural frequencies as low as 3 Hz. However, certain systems, which incorporated an embedded base of the statue, were much stiffer with frequencies around 14 Hz. It is noted that this type of testing requires significant contact and excitation of the statue. This rare opportunity to work directly with the statues resulted in a valuable dataset summarizing their dynamic characteristics for museum engineers and curators. In cases where rigidity is not attained, there is concern that the statue's natural frequency may be too close to that of the anticipated floor motions. For this reason, a simple and non-intrusive base isolation system is detailed. This system was further verified through shake table testing and is shown to sufficiently reduce earthquake demands to the statue.
Damage of the historical monuments was reported during the earthquakes in the nearby underground tunnels such as twin tunnels. The dynamic stress concentration has been used as a major parameter that evaluates the damage of underground structures. In this study, the dynamic interaction between arge-Karim Khani citadel and twin tunnels was investigated subjected to seismic P waves. The scattered wave fields by twin tunnels were determined with wave function expansion and Fourier transform criteria. In this regard, a new approach was employed to determine scattering based on dynamic stress concentration criteria around two circular tunnels. The seismic responses of twin tunnels were calculated with a verified finite element method using different ranges of the incident seismic wave. The dimensionless analysis was used to evaluate DSCF as known criteria to evaluate scattering. In this way, the different ranges of variables including incident wave angles, frequencies, tunnel sizes, and distance between monitoring point and tunnel center were considered in dimensionless analysis. The results illustrate that DSCF was decreased with increasing the position off the monitoring point and reducing the size of tunnels.
