ISSN (Online) : 2319 - 8753 ISSN (Print) : 2347 - 6710 International Journal of Innovative Research in Science, Engineering and Technology An ISO 3297: 2007 Certified Organization Volume 3, Special Issue 4, March 2014 National Conference on Recent Advances in Civil Engineering (NCRACE-2013) During 15-16 November, 2013 Organized by Department of Civil Engineering, North Eastern Regional Institute of Science and Technology, Nirjuli, Itanagar, Arunachal Pradesh, India. Copyright to IJIRSET www.ijirset.com 144 Finite Element modelling of ‘Rang Ghar’ monument, Assam Shashank Burman 1 , Kumar Pallav 2 , Konjengbam Darunkumar Singh 3 Undergraduate Student, Department of Civil Engineering, IIT Guwahati, India 1 Assistant Professor, Department of Civil Engineering MNNIT Allahabad 2 Associate Professor, Department of Civil Engineering, IIT Guwahati, India 3 Abstract: This paper presents the results of static and dynamic analyses of the masonry monumental structure ‘Rang Ghar’ constructed during the Ahom dynasty (1744-1751 AD) in Sibsagar district of Assam, India, using the commercial finite element (FE) software, Abaqus (2010). Rang Ghar is a two storied masonry monumental structure of 12 meter height, with a dome type roof, thick masonry walls and a series of arch openings at both floors. The static analysis shows that, in general, the structural configuration of the masonry complex is adequate to withstand gravity loads (self weight and live load). Most stressed region is the entrance arch walls at the ground level with a maximum value of compressive stress of about 0.45 MPa. Also, displacement resultant distribution suggests that a maximum displacement of around 0.94 mm at top arch roof. Based on the dynamic analysis, first three mode shapes of the Rang Ghar have been presented. Keywords: Ran Ghar, FE Modelling, Static and Dynamic analysis, Modal Analysis. I. INTRODUCTION North-East India is seismically one of the most active regions of the world. The Indian Standard code of practice [8] identified north-east India, including Assam as a highly seismic zone by placing it in the highest zonal level i.e. zone V. The northeastern part of India has an exceptionally complex tectonic and geologic setup. It has the Himalayan mountain belt in the north, Mishmi hills in the west, Naga Patkoi mountain range in the south, and the Brahmaputra plain at the middle, along with the Shillong Plateau, the Burmese arc, the Tripura folded belt, and the Surma Valley, that makes this region among most seismically active regions of the world [15,19]. In the literature [2, 5] it is reported that the first known historic event for Northeastern region occurred near Guwahati around 825-835 A.D. (Mw ~8.0). [11] provided a list historical earthquakes, prior to 18 century A.D. Damages due to two major earthquakes i.e., the 1869 Cachar and the 1897 Great Assam earthquakes were well documented in [16,18]. As much as 18 large earthquakes (Mw > 7) have occurred in the recent centuries including the great earthquakes of Shillong (12.06.1897, Mw 8.7) and Assam-Tibet border (15.08.1950, Mw 8.6) [12, 15, 17]. Hence, it has become pertinent to assess the structural behaviour of landmark historical masonry monuments such as Ranghar, Kachari palace, Ahom Raja palace, Ghanashyam's house, Karengghar, etc., both due to static and anticipated earthquake loads. Many of these monuments have shown signs of damages due to material ageing, soil settlement etc., in addition to the possible earthquake effects. High seismic vulnerability historical structures can arise, both to the particular configuration (often characterized by open space, slender walls, lack of effective connections among the structural elements) and to the mechanical properties of masonry material (highly nonlinear behaviour and very small tensile strength) [3]. Structural analyses using state of art FE approach would enable to identify repairs and retrofitting techniques. Hence, in the present study, an attempt has been made to conduct static and dynamic structural analyses of an old masonry structure ‘Ranghar’ by employing finite element analysis using Abaqus [1] II. DESCRIPTION OF RANGHAR Rang Ghar is a two storied royal pavilion of Ahom kings with unique architectural features. The amphitheatre of