Repairing and Recovering Structural Performance of Earthen Walls Used in Japanese Dozo-Style Structures After Seismic Damage
Hajime Yokouchi*, and Yoshimitsu Ohashi**
4-28-1 Setagaya, Setagaya-ku, Tokyo 154-8515, Japan
**Tokyo City University, Tokyo, Japan
Several traditional building group districts exist in Japan as a system for preserving the remaining historical villages and townscapes of the country, along with their surrounding environment. In the northern Kanto region of Japan, there remain examples of many dozo-style structures called “Dozo-dukuri,” forming a distinctive historical townscape. In the 2011 Tohoku Region Pacific Offshore Earthquake, the traditional townscapes and dozo-style structures of the Kanto region were seriously damaged. When restoring the walls of damaged dozo-style structures to a sound condition, demolishing and reconstructing all the mud requires considerable labor; moreover, few modern artisans can construct mud walls. However, if there was a method that could recover the structural performance of the walls immediately via partial repair, the restoration of the walls could again become economical. Therefore, in this study, we first surveyed the specifications of mud walls in the northern Kanto region. Then, we performed horizontal loading tests on full-scale walls produced according to the survey results to determine the structural performance of walls under a horizontal force, e.g., an earthquake. Further, a test specimen damaged by a horizontal force was repaired, and a horizontal loading test was performed again. The results elucidated the structural performance recoverability obtained by the proposed repair method.
-  H. Yokouchi and Y. Ohashi, “Earthquake resistance evaluations and seismic damage assessment of Japanese traditional building in Tochigi,” Proc. of the 15th World Conf. on Earthquake Engineering, No.1272, 2012.
-  Joint Editorial Committee for the Report on the Great East Japan Earthquake Disaster, “Report on the Great East Japan Earthquake Disaster, Building Series Vol.4, Structural Damage to Timber Buildings / Damage of Historic Buildings,” Architectural Institute of Japan, 2015 (in Japanese).
-  C. Kawashima, “Design of private houses, Overseas version,” Suiyosha Publishing Inc., pp. 67-96, 2016 (in Japanese).
-  K. Ohta, “Wooden building in Eastern Europe,” Sagami-Syobo, pp. 39-48, 1988 (in Japanese).
-  E. Fodde, “Traditional Earthen Building Techniques in Central Asia,” Int. J. of Architectural Heritage, Vol.3, No.2, pp. 145-168, 2009.
-  N. Quinn, D. D’Ayala, and T. Descamps, “Structural Characterization and Numerical Modeling of Historic Quincha Walls,” Int. J. of Architectural Heritage, Vol.10, No.2-3, pp. 300-331, 2016.
-  M. Blondet, J. Vargas-Neumann, N. Tarque, J. Soto, C. Sosa, and J. Sarmiento, “Seismic protection of earthen vernacular and historical constructions,” Proc. of the 10th Int. Conf. on Structural Analysis of Historical Constructions, pp. 3-14, 2016.
-  M. R. Maheri, A. Maheri, S. Pourfallah, R. Azarm, and A. Hadjipour, “Improving the Durability of Straw-Reinforced Clay Plaster Cladding for Earthen Buildings,” Int. J. of Architectural Heritage, Vol.5, No.3, pp. 349-366, 2011.
-  Q. Ali, N. Ahmad, M. Ashraf, M. Rashid, and T. Schacher, “Shake Table Tests on Single-Story Dhajji Dewari Traditional Buildings,” Int. J. of Architectural Heritage, Vol.11, No.7, pp. 1046-1059, 2017.
-  National Institute for Land and Infrastructure Management, “Technical manual on the shear wall factor of mud wall, surface lattice wall and inserted wooden siding wall,” Japanese Housing and Wood Technology Center, pp. 144-147, 2004 (in Japanese).
-  A. Shibata, “Dynamic Analysis of Earthquake Resistant Structures,” Tohoku University Press, 2010.
-  National Institute for Land and Infrastructure Management, Building Research Institute, “Allowable Stress Design for House with Timber Frame Construction (2017 Edition),” Japanese Housing and Wood Technology Center, pp. 300-301, 2017 (in Japanese).