Journal of Earthquake Engineering ISSN: 1363-2469 (Print) 1559-808X (Online) Journal homepage: http://www.tandfonline.com/loi/ueqe20 Damage to Cultural Heritage Structures and Buildings Due to the 2015 Nepal Gorkha Earthquake Satish Bhagat, H. A. D. Samith Buddika, Rohit Kumar Adhikari, Anuja Shrestha, Sanjeema Bajracharya, Rejina Joshi, Jenisha Singh, Rajali Maharjan & Anil C. Wijeyewickrema To cite this article: Satish Bhagat, H. A. D. Samith Buddika, Rohit Kumar Adhikari, Anuja Shrestha, Sanjeema Bajracharya, Rejina Joshi, Jenisha Singh, Rajali Maharjan & Anil C. Wijeyewickrema (2018) Damage to Cultural Heritage Structures and Buildings Due to the 2015 Nepal Gorkha Earthquake, Journal of Earthquake Engineering, 22:10, 1861-1880, DOI: 10.1080/13632469.2017.1309608 To link to this article: https://doi.org/10.1080/13632469.2017.1309608 Published online: 23 Jun 2017. Submit your article to this journal Article views: 265 View Crossmark data Citing articles: 2 View citing articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ueqe20 JOURNAL OF EARTHQUAKE ENGINEERING 2018, VOL. 22, NO. 10, 1861–1880 https://doi.org/10.1080/13632469.2017.1309608 Damage to Cultural Heritage Structures and Buildings Due to the 2015 Nepal Gorkha Earthquake Satish Bhagata, H. A. D. Samith Buddikaa, Rohit Kumar Adhikaria, Anuja Shresthaa, Sanjeema Bajracharyaa, Rejina Joshia, Jenisha Singha, Rajali Maharjanb, and Anil C. Wijeyewickremaa aDepartment of Civil and Environmental Engineering, Tokyo Institute of Technology, Tokyo, Japan; bDepartment of International Development Engineering, Tokyo Institute of Technology, Tokyo, Japan ABSTRACT ARTICLE HISTORY Cultural heritage structures are an integral facet of the irreplaceable Received 10 February 2017 cultural heritage of a nation and have been constructed several hun- Accepted 27 February 2017 fi dreds and even thousands of years ago. In this paper, based on a eld KEYWORDS reconnaissance of the highly damaged areas of Kathmandu Valley and Cultural Heritage Structures; Sindhupalchowk district, damage to cultural heritage structures due to Earthquake Reconnaissance the 2015 Nepal Gorkha earthquake and its impact on Nepal are Survey; Engineered and reported. Damages to engineered and non-engineered buildings are Non-Engineered Buildings; also discussed. The damage patterns observed and discussed will be Structural Damage; 2015 useful for the prevention of damage to cultural heritage structures and Nepal Gorkha Earthquake other buildings in seismically active countries. 1. Introduction An earthquake of momentous magnitude ðMwÞ 7.8 occurred in the central region of Nepal on April 25, 2015, at 11:56 Nepal Standard Time. The epicenter (28.147°N, 84.708°E) of the earthquake was located in the village of Barpak, Gorkha district, which is approxi- mately 78 km northwest of the capital city, Kathmandu (Fig. 1), and its focal depth was 15 km [USGS, 2015]. Over 472 aftershocks with Mw greater than 4.0 have been recorded as of October 2016 [NSC, 2016], with some significant seismic events having Mw 6:7 on April 26, 2015, and Mw 7:3 on May 12, 2015 (Fig. 1). The earthquake resulted in a Maximum Mercalli Intensity of IX (Violent) with about 8790 deaths, and 22,300 people injured [NPC, 2015]. Significant damages to many public and private buildings were reported. In addition, many cultural heritage structures were also damaged, ranging from moderate damage to total collapse. It was reported that 2900 structures with a historical and religious significance were affected [NPC, 2015], of which 133 had collapsed, 95 were partially collapsed and 515 were partly damaged [DOA, 2015]. The cultural heritage of a nation depicts the social beliefs, customs, and traditions that connect people and provide a sense of unity and belonging to a nation. Cultural heritage structures (i.e. tangible cultural heritage) also serve as tourist attractions but are vulnerable to strong ground shaking due to seismic events, as these structures were obviously built before structural design guidelines were established. The traditional materials used for the CONTACT Anil C. Wijeyewickrema [email protected] Department of Civil and Environmental Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan. Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/ueqe. © 2018 Taylor & Francis Group, LLC 1862 S. BHAGAT ET AL. Figure 1. Location of the mainshock and two major aftershocks of the 2015 Nepal Gorkha earthquake [modified from Parajuli and Kiyono, 2015]. Note: Kathmandu Valley consists of Kathmandu, Lalitpur, and Bhaktapur districts. construction of cultural heritage structures need proper maintenance at regular intervals to maintain structural integrity. Lack of regular maintenance and deterioration of con- struction materials can lead to significant damage to these structures, even under minor ground motion intensity levels. Damage to cultural heritage structures in Italy are discussed in detail by Parisi and Augenti [2013]. Protection of cultural heritage structures is always a matter of concern and has gained significant attention in many European countries [Kappos et al., 2007; Milani and Valente, 2015]. In Nepal, the Ancient Monuments Preservation Act empowers the Department of Archeology to be responsible for all heritage sites in the country. Inadequate resources and mechanisms to implement projects and protect heritage sites, and conflicting interests of multiple stakeholders involved in conservation and mainte- nance of heritage structures, have led to a situation where there are problems with the implementation of regular maintenance of all cultural heritage structures [Chapagain, 2008]. This resulted in extensive damage to cultural heritage structures due to the 2015 Nepal Gorkha earthquake. Many engineered and non-engineered buildings were also damaged due to the 2015 Nepal Gorkha earthquake. A total of 498,852 buildings were fully damaged and 256,697 buildings were partially damaged [NPC, 2015]. This includes both engineered and non-engineered buildings. Damage to buildings due to the 2015 Nepal Gorkha earthquake have been reported in many studies [for e.g. Adhikari et al., 2015;SunandYan,2015;Godaet al., 2015;Shakya and Kawan, 2016;Sharmaet al., 2016]. These studies mainly focused on damage to JOURNAL OF EARTHQUAKE ENGINEERING 1863 reinforced concrete buildings highlighting some of the major causes such as weak column- strong beam mechanism, lack of confining reinforcement, low-quality construction materi- als, and poor reinforcement detailing. Parajuli and Kiyono [2015] investigated damage to stone masonry structures. However, these studies do not discuss damage to cultural heritage structures, which are one of the most valuable cultural assets of a nation. In the last few decades, shortly after the occurrence of a major seismic event, many reconnaissance surveys have been carried out by different groups of researchers. The reconnais- sance surveys mainly focusing on structural damage can be broadly categorized as focusing on (a) damage to building structures [e.g. Tsai et al., 2000;Eberhardet al., 2010;Kawashimaet al., 2010;Romãoet al., 2013; Parajuli and Kiyono 2015; Lukkunaprasit et al., 2016;Yazganet al., 2016]; (b) damage to cultural heritage structures [e.g. Leite et al., 2013; Sorrentino et al., 2014; Adami et al., 2016] (c) seismic pounding of buildings [e.g. Kasai and Maison, 1997;Coleet al. 2012]; and (d) damage to bridges [e.g. Kawashima et al., 2009; Schanack et al. 2012]. The present paper reports the findings of the earthquake reconnaissance after the 2015 Nepal Gorkha earthquake, where the focus is on the damage caused to cultural heritage structures and the resulting impact on Nepal. A field reconnaissance of the highly damaged areas of Kathmandu Valley (which consists of Kathmandu, Lalitpur, and Bhaktapur districts) and Sindhupalchowk district (Fig. 1) was conducted by a team from the Tokyo Institute of Technology, Japan from June 1 to 8, 2015. In addition, damage to engineered and non- engineered buildings located in areas where there were a large number of casualties is also discussed. The observations and related discussionsprovidedinthispaperwouldbeusefulwhen formulating plans to preserve cultural heritage structures and other buildings from future earthquakes in seismically active nations. 2. Characteristics of Nepalese Heritage Structures Kathmandu Valley has seven monument zones included in the list of UNESCO World heritage sites, revealing a wide range of historic and artistic achievements over the centuries. These monument zones include the Durbar Squares of Kathmandu, Patan, and Bhaktapur, the Buddhist stupas of Swayambhu and Boudhanath, and the Hindu temples of Pashupatinath and Changu Narayan [UNESCO, 2016]. All these cultural heritage structures have unique features and depict the traditions and culture of Nepal. Besides this, the design approach, materials, and craftsmanship adopted during the construction of these structures represent the ancient remarkable architectural typologies. Most of these cultural heritage structures are built using stone masonry and brick masonry bonded withmudmortarorlimemortar,whicheasily deterioratewithtime(inafewofthesestructuresthemainframeismadeoftimber),thus making them susceptible to damage under lateral shaking. In general, Nepalese temples can be broadly grouped into three categories based on their architectural