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“...Technology
COMMISSION II
KEYWORDS: IT Documentation, Risk Preparedness, Nepal, Built Heritage, Natural Hazards, Capacity-Building, Digital Workflows for Heritage Conservation, 3D Imaging, Georadar, Photogrammetry, Electronic Distance Measurements (EDM), Computer-Aided Drawing.
ABSTRACT:
On 25 April 2015, the Gorkha earthquake of magnitude 7.8, severely damaged the cultural heritage sites of Nepal. In particular, the seven monument zones of the Kathmandu Valley World Heritage Site suffered extensive damage. Out of 195 surveyed monuments, 38 have completely collapsed and 157 partially damaged (DoA, 2015). In particular, the world historic city of Bhaktapur was heavily affected by the earthquake. There is, in general, a lack of knowledge regarding the traditional construction technology used in many of the most important temple monuments in Bhaktapur. To address this limitation and to assist in reconstruction and rehabilitation of the area, this study documents the existing condition of different...”
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“...(Schuller, 2003). Due to the critical heritage value of the temple, destructive evaluation of the structure to determine material properties was not possible. Therefore, any analysis must rely on qualitative observation of material condition and damage and literature on the strength and material properties from similar structures. A bounded analysis will provide a range of structural behaviour based on a likely range of material properties.
To assess future performance, a seismic structural investigation of the tallest temple in Nepal, the Nyatapola temple in Bhaktapur, will be conducted. This temple survived the earthquake well with some minor damage to the upper tiers of the temple; however, it is not clear what the exact extent of the existing damage is, why this temple was resistant to collapse, or how the temple will perform in a potential fixture earthquake. One primary goal of this investigation is to determine what aspects of the traditional construction technology are present and had...”
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“...capacity to do similar work in future. The focused project location for this study is Taumadhi Square in the Bhaktapur World Heritage Site (WHS). At the north end of the square is the five-tiered temple with a square footprint called the Nyatapola Temple. This temple is the tallest in Nepal and was constructed in 1701/1702 AD by King Bhupatindra Malla. Since its construction, this structure has resisted three major earthquakes (Mw 8.0 in 1833, Mw 8.4 in 1934, and Mw 7.8 in 2015) without major damage. It is clear that the study of this monument and its traditional construction technology has significant consequences for the seismic performance of other structures in the valley and equally important to digitally record structure before any other catastrophic disaster. The other major structure studied in Taumadhi Square is the Bhairavnath Temple on the eastern side, which is a three-tier temple with a rectangular footprint.
In addition to the Taumadhi Square, recording, documentation and ...”
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“...deodara) and Gobresalla (Pinus roxbughii) were used in the construction (Vaidya, 2004). Two major features of this remarkable construction are the nse of a higher plinth and no internal floors above the first-floor level forming open well type structure (Figure 9,10).
inwards from the level below, i.e., the outer edge of the upper wall is aligned roughly with the center of the wall below. The walls of each level were constructed just above timber beams. 3.2.2 Recording of existing damage condition
Major damage is concentrated in upper tier of structure and wall was found to be partially collapsed. The upper tier was recorded to be collapsed in previous 1934 AD earthquake as well and which is reconstructed later on. A major renovation was done during 1996 AD by Bhaktapur Municipality in which majorly roof was repaired wooden post in the upper tier was replaced after founding it was decayed (Figure 11) (Bhaktapur, 1998). This also suggests that there may be the presence of the timber element...”
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“...ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume IV-2/W2, 2017 26th International CIPA Symposium 2017, 28 August-01 September 2017, Ottawa, Canada
Existing damage in the structure is digitally recorded using the photogrammetry and laser scanning data. Partially collapsed top wall was found to be torsionally distorted by approximately 3.557° clockwise in respect to the base of the superstructure. However, several shear cracks developed in the doorway on all four-side wall also identified. High-quality orthophotos are generated from the close-range laser scanning and photogrammetric models. These orthophotos were used for mapping existing cracks in the wall (figure 12). Mapping of these cracks will then be introduced in the finite element modeling for assessing the existing performance of structure in future.
Figure 12. Mapping of existing cracks in structural wall
3.2.3 Geo- Radar Investigation
In addition to the surface documentation using laser...”
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“...the interior wall, and exterior photogrammetry.
AtTaumadhi Square:
• Bhairavnath Temple - Complete georadar evaluation of the walls, laser scanning of the interior and exterior, terrestrial and aerial photogrammetry, ambient vibration dynamic analysis.
5. CONCLUSION
The research aims to contribute to the conservation process for the historic buildings in Bhaktapur, Nepal which suffered damage in the 2015 earthquake. The outcome of research addresses the important difficulties related to the preparation of existing condition drawings, acquisition of data on material properties, internal morphology and damage, and determination of structural load paths.
In this study, an existing methodology for digital recording is implemented for recording heritage structure of Kathmandu Valley and comparative studies were made. This will contribute towards adaptation of the sustainable recording methodology suitable for the Kathmandu Valley Heritage.
Furthermore, uncertainty related with timber structure...”
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“...Symposium 2017, 28 August-01 September 2017, Ottawa, Canada
REFERENCES
Bernier, R.M., 1979. The Nepalese Pagoda Origins and Style
Bhaktapur., 1998. Nyatapola Jimodwar ko Bibaran, Bhaktapur Monthly Magazine Vol. 150, pp. 18-26
Binda, L., Colla, C. & Forde, M.C.,1994. Identification of moisture capillarity in masonry using digital impulse radar, J. Construction & Building Materials, Vol. 8, No. 2, pp. 101-107.
Binda, L., Saisi, A., Tirabosehi, C., 2001. Application of Sonic Tests to the Diagnosis of Damage and Repaired Structures, Non Destructive Testing and Evaluation Int., 34(2), 123- 138.
Binda, L, Saisi, A., Gerosa, L. & Lenzi, G., 1997. GPR application to multiple leaf stone masonries, Proc. of the International Colloquium “Inspection and Monitoring of the Architectural Heritage”, IABSE-ISMES, pp. 215-222.
Binda, L., Lenzi, G. & Saisi, A., 1998. NDE of masonry structures: use of radar test for the characterisation of stone masonries, J. Non Destructive Testing and Evaluation International...”
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