ABSTRACT

The 2015 Gorkha earthquake damaged many unreinforced masonry buildings in the UNESCO World Heritage Sites of Kathmandu Valley, such as Kathmandu, Patan, and Bhaktapur. But there were a few multi-tiered temples, with high plinths, that survived the recent earthquake. The temples with a massive high plinth have shown better seismic performance both in past historical earthquakes as well as in the recent 2015 earthquake. In this paper, the results of a reconnaissance survey conducted to assess the seismic effect on the high plinth caused by the 2015 Gorkha earthquake is presented first. Extensive field investigation of excavation works indicates the bulky volume of the traditional construction materials were used to build the high plinth with distinct construction techniques. Second, the dynamic properties of high plinths of nine Nepalese temples measured from microtremor data are presented. The damage assessment shows that the 2015 Gorkha earthquake had minor effects on the plinths. The predominant frequencies obtained at the ground points nearby the temples vary from 0.44–1.32 Hz and predominant frequencies obtained from the H/V spectral ratio ranged 2.88–12.70 Hz. Damping ratios obtained vary from 2.01–8.50%. 1-D wave propagation shows that the plinth act as damping agent.

摘要

2015 年廓尔喀地震破坏了加德满都、帕坦和巴克塔普尔等联合国教科文组织世界遗产地加德满都谷地的许多未加固砌体建筑。但是有一些多层的寺庙，有高基座，在最近的地震中幸存下来。具有巨大高基座的寺庙在过去的历史地震以及最近的 2015 年地震中都表现出更好的抗震性能。在本文中，首先介绍了为评估 2015 年廓尔喀地震对高基座的地震影响而进行的勘测结果。对挖掘工程的广泛现场调查表明，传统建筑材料的体积庞大，用于建造具有独特施工技术的高基座。第二，介绍了从微震数据测量的九个尼泊尔寺庙高基座的动态特性。损坏评估表明，2015 年廓尔喀地震对基座的影响较小。在寺庙附近的地面点获得的主要频率在 0.44-1.32 Hz 之间变化，从 H/V 频谱比获得的主要频率范围为 2.88-12.70 Hz。获得的阻尼比从 2.01% 到 8.50% 不等。1-D 波传播表明基座充当阻尼剂。获得的阻尼比从 2.01% 到 8.50% 不等。1-D 波传播表明基座充当阻尼剂。获得的阻尼比从 2.01% 到 8.50% 不等。1-D 波传播表明基座充当阻尼剂。