Field Survey on the construction time, the heritage registration and the stability of the Longyou Caves in Zhejiang Province, China

本研究的目的是阐明1992年在中国浙江省龙游发现的五个巨大地下洞室周围岩石的劣化和风化状态。一些当地的历史学家指出，它们大约建于2，300 - 2，400年前（春秋时期）。我们需要通过岩石力学和保护科学研究如下：1）地质调查：除了地形和地质调查外，还应用了电法（电阻率法）。详细调查了地质构造、开口结构、断层和裂缝。2）地下开口的尺寸：而不是传统的激光过境，这被认为需要非常长的时间。最新的3D-Scanner系统。在一周内测量了四个开口的精确尺寸。3）岩石的物理性质：岩石样品从表面取样， ...更多信息 并从颗粒分布、崩解性、矿物组成、差热行为、比表面积、孔径、盐渍化及生物风化效应等方面进行了分析。结果表明，粘土矿物的膨胀压力和溶解性是风化过程的主要原因，氢离子浓度的变化可以作为表征风化过程的一个很好的指标。4）洞穴环境监测：连续两年对洞穴内的温度、相对湿度、照度和气压进行了监测。建立了地下洞室环境数据库。根据这次调查和各个开口上方地面电阻率的分布，我们建议当地政府（负责保护开口）拆除几个本应招待游客的人工水库。5）沉积物分析：确定开孔的施工时间是关键。由于海关规定，不允许运输从开口底部取样的疯狂沉积物。最重要的是，我们发现电阻率法，三维激光扫描和氢离子分析的应用非常有用，并且成功地建立了通过非破坏性方法调查有价值的遗产遗址的新途径，调查，综合信息。少

The objective of this research is to clarify a state of deterioration and weathering of rock, surrounding the five huge underground openings which were found in Longyou, Zhejiang Province, China, 1992. Several local historians pointed out that they were constructed approximately 2,300-2,400 years ago (the Spring-and-Autumn Period). We needed to study through rock mechanics and conservation science as follows:1) Geological survey: In addition to topography and geological surveys, the electric prospecting (Electric Resistivity Method) was applied. The geological formations, structure of the openings, faults and fissures were investigated in detail.2) Dimensions of the underground openings: Instead of a conventional laser transit, which was considered to require a tremendously long time for. survey, the latest 3D-Scanner system was employed. The precise dimensions of four openings were measured in one week.3) Physical properties of rock: Rock specimens were sampled from the surface and th … More e wall of openings, and analyzed from the points of view on particle distribution, slakability, mineral components, differential thermal behavior, specific surface area, pore size, salinization and biological weathering effect. We concluded that swelling pressure and solubility of clay minerals are main causes in weathering process, and a change of hydrogen ion concentration can be a good indicator for characterization.4) Environmental monitoring in caves: Temperature, relative humidity, illuminance, and barometric pressure have been measured continuously over two years. We establish the data base for the environment of the underground opening. from this survey and the distribution of electric resistivity in the ground above the respective openings we suggested the local government (charged in preserving the openings) to remove several man-made reservoirs which were supposed to entertain visitors. The seeping water from the reservoirs remarkably accelerated weathering damage.5) Analysis of sediments: it was the key issue for us to identify a construction time of the openings. Due to the custom regulations it was not allowed to transport the mad sediments which had been sampled from the bottoms of the openings.Above all, we found that the application of the Electric Resistivity Method, the 3D Laser Scanning, and the hydrogen ion analysis were very informative, and it was successful to establish the new access to investigate valuable heritage sites through the non-destructive methods, surveys, and integrated information. Less