Analysis of Existing Masonry Heritage Building Subjected to Earthquake Loading Procedia Engineering 173 ( 2017 ) 1833 – 1840 Available online at www sciencedirect com 1877 7058 © 2017 The Authors Publ[.]
Available online at www.sciencedirect.com ScienceDirect Procedia Engineering 173 (2017) 1833 – 1840 11th International Symposium on Plasticity and Impact Mechanics, Implast 2016 Analysis of existing masonry heritage building subjected to earthquake loading M Shariqa,*, S Haseebb and M Arifc a Assistant Professor, Department of Civil Engineering, AMU Aligarh 202002, India b M Tech.,Student, Department of Civil Engineering, AMU Aligarh 202002, India c Professor, Department of Civil Engineering, AMU Aligarh 202002, India Abstract In the present study, the finite element analysis has been carried out on masonry building subjected to earthquake loading For this purpose, an existing masonry heritage building situated in Aligarh city has been chosen The time history method using ElCentro earthquake data has been employed for seismic performance of the chosen building The maximum principal tensile stress and maximum shear stress has been observed and compared with permissible stresses It has been found that these stresses exceed the permissible limit at few locations such as dome-wall junction, wall-roof junctions and the minarets It has also been found that these locations are the most critical portion of the building under earthquake forces © 2017 The Authors Published by Elsevier Ltd This is an open access article under the CC BY-NC-ND license © 2016 The Authors Published by Elsevier Ltd (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-reviewunder under responsibility of organizing the organizing committee of Implast Peer-review responsibility of the committee of Implast 2016 2016 Keywords: Masonry heritage building; FEM; earthquake loading; maximum principal tensile stress; maximum shear stress Introduction It is well known fact that the effect of earthquake forces on building is unpredictable and can occur at any time and at any place Masonry building whether residential or historical/heritage have high compressive strength but low tensile strength Analysis and strengthening of heritage building subjected to earthquake loading has always been a challenging task because of its geometrical complexity and lack of knowledge about the used material, structural modifications during the time and ageing of material Past studies [1-6] show that the critical issues affecting the * Corresponding author Tel.: +91-9897903968 E-mail address: mshariqdce@gmail.com 1877-7058 © 2017 The Authors Published by Elsevier Ltd This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the organizing committee of Implast 2016 doi:10.1016/j.proeng.2016.12.229 1834 M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 seismic response of historic masonry buildings namely masonry quality; connections among structural elements; diaphragm flexibility; out-of plane resistance of masonry walls; structural irregularities; wrong retrofit interventions and earthquake ground motion characteristics In some studies [7-10] finite element analysis has also been carried out on masonry buildings subjected to earthquake forces It has been found that the memory and time requirements become too large and if a compromise between accuracy and economy is needed, a macro-modeling strategy is likely to be more efficient Past studies show that the existing forms of the buildings are highly vulnerable for future earthquake Due to increase the seismic activities in every part of the country, there is a need of research to preserve and examine the performance of masonry heritage buildings under earthquake loading, particularly with regard to wall-floor connections and openings Aligarh is located at 27.88 degree N, 78.08 degree E in the province of Uttar Pradesh, India It has an average elevation of 178 m (587) Aligarh falls in seismic zone IV as per IS: 1893 (2002) which is a high seismicity zone The Jama Masjid of Aligarh Muslim University (AMU) is a heritage building and needs to be analyzed under heavy earthquake forces Fig and shows the front and back view of Jama Masjid, AMU respectively Fig Front view of Jama Masjid Fig Backside view of Jama Masjid Finite element modeling (FEM) The finite element modeling of mosque was carried out using macro-modeling techniques due to the reduced time and memory requirements as well as user friendly mesh generation This type of modeling is most valuable when a compromise between accuracy and efficiency is needed The whole building is analyzed using shell/plate elements with triangular plate elements are used in the arches and domes while quadrilateral plate elements are used for the rest of the structure 2.1 Geometric properties for jama masjid The structure is very massive, the walls in the structure are very thick more than 1.5 m at the central portion of the building Height of building is m at left and right side of the building while the central portion of the building is 11 m high The building has one central dome of diameter 7.3 m and two other domes of smaller diameter at either side of the building of diameter 5.2 m The whole structure is symmetrical about one axis having two minarets at either end of height 24 m The building rests on a very firm soil Hence the support condition is taken as fixed Masonry columns are provided in the buildings The structure has a large number of openings at the front side of the structure whereas very few openings of very less dimension is present at the backside of the structures The openings present at the backside of the structure are not considered in the model because these openings are of very less dimension which does not have much effect on the stiffness The openings are provided in the form of arches, the modeling of these arches is very complex and time consuming 1835 M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 2.2 Mechanical properties for jama masjid The mechanical properties of the material given in Table have been taken from the literature [11] for the seismic analysis of existing masonry heritage building Table Mechanical properties of the material Material Modulus of Poisson’s ratio Mass density elasticity ‘μ’ (kN /m3) ‘E’ (N/mm ) Brick masonry 2100 0.13 19.2 2.3 Finite element model for jama masjid The FEM of jama masjid chosen as masonry heritage building has been carried out using commercially available finite element software The parts of the building are first modeled using plate element and then fine meshing has been done in order to get better results Proper connectivity is ensured throughout the structure by varying the size of the mesh at few places as well as by using triangular plates in place of rectangular plates Triangular plates are also used in the structure where arches are present and are also used in the dome to provide proper connectivity The total number of plate elements and nodes used in the FEM is 30391 and 30308 respectively Fig to are showing the salient features of the analytical finite element model of the heritage building chosen for the present investigation Fig Backside view of the FEM Fig 3D front view of the FEM Fig FEM showing nodes and plates in the structure Results and discussion The building has been analyzed by using the acceleration vs time data of El Centro earthquake as seismic input ground motion The structure is analyzed considering the seismic forces in X and Z directions The permissible values of the stresses given in [12], taken as tensile stress and shear stress must not exceed 0.07 MPa and 0.25 MPa respectively 3.1 Maximum principal tensile stresses for earthquake in X direction It can be seen from Fig that the maximum value of tensile stress is observed as 1.12 N/mm² In most of the parts of the building, the tensile stresses are within permissible limits but the value is exceeding at the dome-wall junction, roof-wall junction and few other parts of the structure 1836 M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 Fig Principal tensile stresses for earthquake loading in X direction M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 3.2 Maximum shear stresses for earthquake in X direction Fig shows that the maximum value of shear stress is observed as 0.544 N/mm² In most of the parts of the building, the shear stresses are within permissible limits but the value is exceeding in few other parts of the structure The maximum value is found to be at the back side of the structure near the corner junction of dome and wall Fig Shear stresses for earthquake loading in X direction 3.3 Maximum principal tensile stresses for earthquake in Z direction The maximum value of tensile stress has been observed is 1.12 N/mm² as shown in Fig which is comparable with the value obtained while considering earthquake in X direction The most part of the structure is experiencing tensile stresses within permissible limits but the value is exceeding at the junction of domes-wall junction and roof- 1837 1838 M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 wall junction and few other parts of the structure The value of tensile stress is also slightly higher at the arches as well as at the junction of two walls Fig Principal tensile stresses for earthquake loading in Z direction 3.4 Maximum shear stresses for earthquake in Z direction From the Fig 9, the maximum value of shear stress is 0.531 N/mm² and slightly lower than the values obtained from earthquake loading in X direction The structure is experiencing shear stresses within permissible limits but M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 value is exceeding at few parts of the structure The maximum value is found to be at the place that is at the back side of the structure at the corner junction of dome and wall Fig Shear stresses for earthquake loading in Z direction 1839 1840 M Shariq et al / Procedia Engineering 173 (2017) 1833 – 1840 Conclusions The principal tensile stresses and shear stresses in the masonry heritage building subjected to earthquake loading in X and Z direction are found within the permissible limit at most part of the structure but the value exceeds beyond the permissible limit at few places The front portion of the building is found to be vulnerable under earthquake loading due to the presence of large number of openings The stresses are beyond the permissible values around the openings The wall-roof junctions and dome-wall junctions and the corners of the adjacent walls are found to be critical while considering the earthquake in any of the two directions The minarets are found be the most critical portion of the structure as per the results of response spectrum analysis of finite element model considering earthquake in X direction The maximum value of the stresses are found be to be at the junction of minaret and the roof References [1] A.W Page, (1995), “Reinforced masonry structures, Australian overview”, Pacific Conference on Earthquake Engineering, PCEE 95 (1995), Melbourne [2] G Magenes, A.D Fontana, Simplified non-linear seismic analysis of masonry buildings, Proc International Masonry Society, (1998) 190195 [3] R Cardoso, M Lopes, R Bento, Seismic evaluation of old masonry buildings, Part I: Method description and application to a case study, Eng Struct 27 (2005) 2024-2035 [4] P.B Lourenco, J.A Roque, Simplified indexes for the seismic vulnerability of ancient masonry buildings, Constr Build Mater 20 (2006) 200-208 [5] F Ceroni, M Pecce, S Sica, A Garofano, Assessment of seismic vulnerability of a historical masonry building, Build (2012) 332-358 [6] F Parisi, N Augenti, Earthquake damages to cultural heritage constructions and simplified assessment of artworks, Eng Fail Analy 34 (2013) 735-760 [7] P.B Lourenco, Computational strategies for masonry structures, PhD dissertation, Delft University of Technology, Holland, 1996 [8] G.V Guinea, J Planas, M Elices, K1 evaluation by the displacement extrapolation technique, Eng Fract Mechan 66 (2000) 243-255 [9] M.A Elgawady, P Lestuzzi, and M Badoux, Analytical model for in-plane shear behaviour of URM walls retrofitted with FRP”, Compos Sci Techno 66 (2006) 459-474 [10] S.S Khadka, Seismic performance of tradational unreinforced masonry building in nepal, Kathmandu University J Sci (2013) 15-28 [11] M Shariq, H Abbas, H Irtaza, M Qamaruddin, Influence of openings on seismic performance of masonry building walls, Build Environm 43 (2008) 1232-1240 [12] IS 1905, Indian Standard Code of Practice for Structural Use of Unreinforced Masonry, Bureau of Indian Standards, New Delhi, India (1987) ... future earthquake Due to increase the seismic activities in every part of the country, there is a need of research to preserve and examine the performance of masonry heritage buildings under earthquake. .. central portion of the building Height of building is m at left and right side of the building while the central portion of the building is 11 m high The building has one central dome of diameter... Simplified non-linear seismic analysis of masonry buildings, Proc International Masonry Society, (1998) 190195 [3] R Cardoso, M Lopes, R Bento, Seismic evaluation of old masonry buildings, Part I: Method