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Capacity curve for the pushover analysis for the model with and without reinforcement in the +Y (control point in the top of the eyvan), -Y and –X (control point in the top of the dome) directions.
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Structural assessment and seismic vulnerability of ancient masonry buildings is a difficult task even when employing advanced specialized technical skills, which requires a complex study. This paper aims to assess the structural and seismic safety of the Esfahan Shah Mosque in Iran by numerically investigating the nonlinear behavior of the mosque f...
Citations
... Assessing the material properties of these structures poses a significant challenge. Researchers have employed various experimental techniques in the literature on damaged and undamaged specimens to ascertain the material properties of historical mosques [43][44][45]. It is essential to note that the natural stone materials utilized in each mosque contribute unique characteristics to the overall structural composition. ...
The earthquakes that occurred on February 6, 2023, in Kahramanmaras¸, Turkiye, caused extensive damage, particularly in historical mosques built with traditional methods. This study aims to investigate the collapse mechanism of Malatya Yeni Mosque, which underwent a strengthening operation before the Kahramanmaras¸ Earthquakes. The primary objective of this study is to offer insights into the rehabilitation of similar structures. Post-earthquake field surveys, combined with finite element modeling and dynamic analysis using city center acceleration data from Malatya, were utilized to assess structural vulnerabilities. The results of numerical analyses and field studies have indicated that seismic damages generally occurred in specific Mosque areas, particularly in the domes, minarets, columns (elephant feet), and arch systems supporting the central dome. The observed damage patterns in these areas signify the zones where the structural inadequacies generally coincide. The main findings of this study shed light on the necessity of strengthening these unique structures exposed to seismic forces and offer an
essential step in minimizing the adverse effects of such disasters in the future. This study guides the planning and implementation of efficacious engineering interventions to preserve historical buildings.
... Other scholars have focused on the spatial functionality of mosque architecture [13,14], its refuge capabilities [15,16], seismic resistance [17,18], dome lighting performance [19], and architectural energy efficiency [20]. Research on individual structures mainly focuses on architectural structural performance [21], column styles [22], and visual comfort [23]. Current research is predominantly concentrated in regions with a high Muslim population, such as Saudi Arabia [24], Iran [25], and Algeria [26], in Western Asia and North Africa. ...
Clarifying the spatiotemporal distribution and influencing factors of mosque architecture in China’s Hehuang region has significant positive implications for the overall protection and development of the region’s architectural cultural heritage. This study utilizes field surveys and acquires POI data of traditional mosques built before 1993 in the region to analyze the distribution characteristics of mosques, aiming to explore future development trends of these religious structures. It also investigates the influencing factors, with the goal of emphasizing the primary and secondary factors affecting mosque distribution. The study finds the following: (1) Mosques are generally centered around the Huangshui Valley, displaying a “central clustering, peripheral dispersal” distribution pattern, forming a spatial structure of “two cores, one belt, multiple points”, with distinct differentiation and overall uneven distribution. (2) Mosques are primarily situated at elevations between 2147 and 2764 m; on slopes less than 15°, in sunny and gentle slopes; within 20 km from rivers; within 14 km from roads; in areas receiving 400–500 mm annual rainfall; and within temperature ranges of 5.54–10.22°C. (3) The study also finds that the spatial distribution of mosques is profoundly influenced by both natural geographical factors and human environmental factors. The better the natural location, the larger and denser the population, the richer the cultural resources, the higher the level of economic development, and the greater the concentration of Hui people, the more numerous and concentrated the mosques. (4) Population factors are the dominant factors for the clustered distribution of traditional mosques in the Hehuang area. Since the construction of mosques in the region is closely related to the number of Hui people and the proportion of Muslim adherents, areas with a high concentration of mosques also have relatively larger populations of Hui people. Temperature, precipitation, altitude, rivers, and roads are foundational factors for traditional mosques in the Hehuang area, influencing mosque distribution as external factors.
... Once convergence is obtained for all the scaled records separately, the vectors must be compared to find the optimal solution. To this purpose the cosine similarity is used (Dinani et al. 2021): where h n and k n are the two generic vectors for which the level of similarity is estimated. All the vectors contained in the last generation matrices (for which the differential evolution algorithm converged) are compared using Eq. ...
In unreinforced masonry structures, among the most dangerous events that can occur during earthquakes are the out-of-plane mechanisms. This type of response significantly changes if the wall is restrained by a horizontal element. The collapse, in this case, could take place for slipping/failure of the diaphragm connection or for overturning of the wall, following the formation of a crack at an intermediate height between the base and the top. A specific analytical model is used to capture the complex dynamic behavior of the wall, formed by two stacked rigid bodies (free to rock) with the top one connected to a flexible diaphragm. The model is calibrated using experimental data available in the literature and it is then used to carry out a dynamic parametric analysis. The variation range of relevant parameters refers to the building features surveyed in Emilia-Romagna region, Italy, and their effect on the global response of the system is investigated. Further, the influence of ground motion is considered, using different ground accelerations. The results of the analysis highlight that, for the considered area and return period, the maximum rotations of the system are significant only for large slenderness values. Further, the investigation shows that the diaphragm plays a crucial role in the dynamic response of the system. The stiffness of the diaphragm can significantly reduce the rotations and consequently the risk of overturning. Additionally, the study on the effect of the wall size pointed out how a top spring causes a reverse scale effect.
... Nevertheless, it merits noting that the lead connectors enhance tensile strength, distinguishing them from their masonry wall counterparts. The literature on historical masonry minaret studies shows that compressive strength values are widely accepted in a range of 5-50 MPa [42][43][44][45]. However, considering the unit stone strength in the studies, compressive strength in the range of 50 MPa has been suggested. ...
Historical minarets are culturally and architecturally significant structures, often susceptible to substantial damage over time due to different load conditions. Therefore, the reinforcement of such buildings holds paramount importance. This study presented a proposal for strengthening historical rubble stone minarets, exemplified by the minaret of Murat Pasha Mosque in Erzurum, Turkey. A finite element model of the minaret was constructed to comprehend its behavior, with the suggested reinforcement method integrated into this model. The impact of the proposed reinforcement on the minaret’s behavior was comprehensively investigated through various numerical methods including modal analyses, pushover analyses, and non-linear dynamic analyses. The analyses revealed that the proposed reinforcement increased the first mode frequency of the minaret by approximately 9.8%. Additionally, it was observed that the reinforcement method augmented the minaret’s lateral load-carrying capacity by 58%. Consequently, it was concluded that the proposed reinforcement technique effectively enhances the minaret’s resilience under demanding conditions, potentially preventing damage. The proposed reinforcement configuration also significantly alters the collapse mechanism of the minaret, as evidenced by the dynamic analysis results, facilitating a more controlled mode of failure. In this regard, it provides a more secure solution by enhancing the minaret’s resilience in an earthquake, thereby reducing environmental safety risks. In conclusion, this study contributes to preserving this invaluable cultural heritage by offering an effective reinforcement method to enchance the seismic resilience of historical minarets. Future research endeavors may further refine these reinforcement techniques and explore alternative material options.
... Historical masonry mosques are susceptible to significant damage when subjected to seismic loads [17][18][19][20]. Common damage mechanisms observed in these mosques include minaret collapse, an out-of-plane overturning of walls, collapse of the narthex, deep cracks in load-bearing walls, and complete structural failure (Fig. 1). ...
... Determining the material properties of these structures, which have been exposed to various influences over the years, can be quite challenging. Researchers have employed various experimental techniques in the literature on damaged and undamaged samples to ascertain the material properties of historical mosques [17,18,51,52]. Moreover, the natural stone materials employed in each mosque possess their unique characteristics. ...
Historic mosques are structures that are highly sensitive to seismic events. Strengthening these buildings, which have been exposed to earthquakes throughout history, and ensuring their safe transfer to future generations is crucial. This research study focuses on three significant historic mosques in the eastern province of Türkiye, Erzurum. Their seismic performance, which has not been extensively studied in the existing literature, is investigated using finite element analysis. Dynamic analyses are conducted, utilizing seismic records from notable earthquakes that have caused significant damage to historic mosques in Türkiye, including the 1992 Erzincan, 1997 Düzce, and 2023 Kahramanmaraş earthquakes. As a result of dynamic analyses, the seismic vulnerability of the considered mosques has been determined. These vulnerable areas include the junctions of load-bearing walls, the dome ring, and the main dome. Based on these findings and considering recommendations from the literature, cost-effective and practical retrofit strategies are proposed to enhance the seismic performance of the mosques. The proposed strengthening aims to improve the interaction between load-bearing walls (diaphragm effect) and reduce displacements in the dome. Dynamic analyses are performed using the retrofitted models to assess the effectiveness of the proposed retrofit measures. These assessments were made considering displacements obtained from the dome and walls and the distribution of global damage. The results of 18 dynamic analyses confirm the efficacy of the suggested retrofit configurations in mosques featuring square plan layouts and single dome architectural styles.
... These approaches provide information related with the collapse mechanism and the force capacity. On the other hand, continuum [30][31][32][33][34] and discrete approaches [35][36][37][38] are preferred when information on the displacement capacity and damage evolution are of particular interest. ...
Conventional formworks for concrete curved shells either are expensive, complex and wasteful or have formal restrictions. Using tile vaults (also known as timbrel, Guastavino, thin-tile or Catalan vaults) as stay-in-place formwork for concrete shells could significantly reduce construction costs and material waste. Tile vaults only require formwork at the boundaries and provide a high formal flexibility. The combination of masonry and reinforced concrete creates a new type of composite structure that needs experimental validation and new structural analysis models to deal with the specific features of the system. This paper presents experimental research on the component materials, load tests on doubly-curved, full-scale prototypes and the definition of a reliable Finite Element structural model for the analysis of the proposed hybrid structure. The experimental research has involved the characterisation of the bricks, mortar, concrete and reinforcement composing the proposed system in order to provide the material properties to be considered in the structural analysis. The construction and testing of two composite sail domes in the laboratory have allowed the validation of the proposed FE model by comparing its predictions with the collapse mechanisms, damage, ultimate loads and load-displacement curves obtained experimentally.
... In this typology, the compressive strength is determined by considering the strength of each leaf [55,69,70]. In addition, in the studies carried out in historical mosques, it is seen that the compressive strength values vary between 2.1 and 4.2 MPa [81][82][83][84][85]. Therefore, a compressive strength of 3 MPa was assumed for both the walls and domes in the finite element models used in this study. ...
Historical mosques are important cultural heritages that should be confidently transferred to the future. These structures are damaged due to earthquakes. The minarets, domes and load-carrying walls of historical mosques are the most damaged and studied in the literature. Field observations made after the earthquakes show that; the narthex part of the historical mosques is also very seismic sensitive. However, there is no study in the literature about the collapse mechanisms of these structures/parts. In this study, 3 narthex places with different architectural features were considered. By creating a finite element model of the narthexes, dynamic analyses were carried out under the earthquake records of 1999 Düzce (Bolu) (Mw = 7.1), 2011 Van (Mw = 7.0), 2020 Elazıg (Sivrice) (Mw = 6.8). An evaluation has been done to assess mode shapes, maximum strains, displacements, damage distributions, and failure mechanisms of the narthex parts. As a result of dynamic analyses, the general collapse mechanism of each narthex was revealed. As a result of all analyses, it has been seen that the most seismically sensitive areas of the narthex are stone columns.
... Both static and kinematic approaches (i.e., lower-bound [45][46][47][48][49][50] and upper-bound [51][52][53][54] theorems, respectively) are a matter of research. However, when there is a specific interest in understanding displacement capacity and damage evolution, researchers often turn to continuum approaches [55][56][57][58][59] or discrete approaches [60][61][62][63]. Due to the masonry's composite character, namely its brittle response in tension, frictional response in shear and anisotropy, its complex structural behaviour is today still difficult to model [64]. ...
The complex structural behaviour of masonry, with its brittle response in tension, frictional response in shear, and anisotropy, makes it challenging to model accurately. Tile vaults, with their unique features such as different binders and bricks placed flat, have distinctive structural performance, and determining the most suitable assessment method is still a subject of debate in both academic and professional circles. This paper presents a study on the structural analysis of tile vaults, aiming at evaluating different numerical approaches for this type of structure. The examination of these approaches and their effectiveness in capturing the structural behaviour of tile vaults intends to offer valuable insights to researchers and professionals in this field. Experimental research was initially carried out in order to provide data for the calibration of the structural models. Two full-scale vaults were tested. Furthermore, several material characterization tests were also performed. The numerical assessment was carried out through limit analysis and non-linear static analysis with numerical models based on the Finite Element Method (FEM). Two FEM models were prepared using different modelling approaches for masonry, namely the macro-modelling and the simplified micro-modelling approaches. The results of the limit analysis presented a load capacity significantly lower than the ultimate load obtained from the experimental tests. The calibrated FEM models presented good results in comparison to the experimental results, namely in terms of damage pattern and load capacity.
... Out-of-plane (OOP) failure for masonry structures is one of the most complex and ill understood subject of seismic analysis according to Paulay and Priestley [1]. If the connections are inadequate, unreinforced masonry (URM) structures are particularly vulnerable to out-of-plane mechanisms during earthquakes [2][3][4][5][6], assuming no masonry disintegration occurs [4]. ...
In unreinforced masonry structures, one of the most dangerous events that can occur during earthquakes is an out-of-plane mechanism. The use of tie rods can be a powerful tool in pre-venting these types of failure mechanisms, especially given the simplicity and the low cost of the strengthening intervention. When the wall is restrained to a horizontal element, such as a tie rod, its response significantly changes. The collapse, in this case, could take place for slipping / failure of the tie rod or for overturning of the wall, following the formation of a crack at an intermediate height between the base and the top.
In the literature are present models accounting for geometric non-linearities in the case of a wall rigidly restrained at the top. The same can be stated for the model free at the top, which considers four different patterns. No model accounting for all previously mentioned phe-nomena while also presenting a non-rigid restraint, is available. Therefore, a model formed by two bodies of finite thickness and a flexible restraint at the top capable to capture the dy-namic response of the system is proposed here. The model is characterized by four motion patterns, and it can detect the transition among them, as well as the collapse mechanisms which can occur for overturning of the entire wall or of the upper body alone.
Explanatory time-histories describe the complex response of the system to recorded ground motion, pointing out its highly non-linear behavior. Finally, the investigation on the influ-ence of the tie rods diameter confirms that the main advantages are obtained for tie rods characterized by a large cross-section.
... In recent years, the seismic behavior of different historical structures has been investigated using this method. The elastic modulus of wall elements in historical structures is proposed in a very wide range [52][53][54][55][56][57][58][59]. In order to reduce this uncertainty, experimental vibration tests in historical structures are important. ...
The protection of historical masonry mosques against earthquakes can be achieved by an accurate assessment of nonlinear behavior, such as heavy damage and collapse. For this reason, historical buildings have been strengthened many times in the past and today. To this end, nonlinear analysis of 3D finite element models of structures is a common and reliable approach. This article examines the seismic performance of historical Molla Siyah Mosques, which are defined as cultural assets by the Ministry of Tourism and Culture of the Republic of Turkey, under the influence of earthquake ground motions. It has been investigated how the concrete vault cover applied to the mosque in previous years affects seismic behavior, force-displacement capacity and collapse mechanism of the structure. The mosque has not been studied before using any advanced numerical simulation method. In addition, no studies have been conducted to determine the damage propagation and collapse mechanisms of the mosque. Detailed finite element model was developed by defining the architectural features of mosque. The finite element model was calibrated in the light of the experimental modal analysis results found in the literature. In order to obtain the seismic behavior and collapse mechanisms of the mosques, nonlinear dynamic analyses were performed using the ground motion records from 1992 Erzincan, 1992 Cape Mendocino and 1995 Kobe earthquakes. An evaluation has been made for concrete cover vault in terms of maximum principal strains, maximum displacements, damage distributions and failure mechanisms of the mosque. It has been determined that the reinforcements applied in historical structures can significantly change the seismic behavior of the structures.
Keywords: historical masonry mosque, crack pattern, collapse mechanism, non-linear dynamic analysis, strong ground motion, restoration effect.
