Design,construction and mechanical behavior of relics of complete large Longyou rock caverns carved in argillaceous siltstone ground  

作　　者：Zhifa Yang1, Zhongqi Yue2, Lihui Li1 1 Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China 2 Department of Civil Engineering, the University of Hong Kong, Hong Kong, China 

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2011年第2期131-152,共22页岩石力学与岩土工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (40902088 and 40672190);the Key Project of Zhejiang Province Science and Technology (2007C23093)

摘　　要：This paper presents a comprehensive summary of data, analyses and findings from the investigations over the past twelve years about the relics of large Longyou rock caverns carved about 2 000 years ago at shallow depths in argillaceous siltstone. The paper presents the typical features associated with the rock caverns. They include structures, large spans, portals, extreme shallow-buried depths, imprints, drainages, inclined ceiling, inclined sidewalls, slender rock pillars, rock staircases, site and strata selections, caving lighting, carving method, and underground construction surveying. They are used to reconstruct and highlight the design and construction methods adopted by the ancients. The paper further demonstrates that the relics of the complete large rock caverns are a consequence of coincidental combinations of ancient human effort and natural factors. The full occupation of water with weak acidity in the large rock caverns with the soft surrounding rocks of weak alkalinity is found to be the main factor ensuring and preserving the caverns to have been stable and integral over 2 000 years. However, the five unwatered complete rock cavern relics have been experiencing various deteriorations and small failures including cracks, seepage, small rock falls and delaminating ceiling rocks. Although these deteriorations have been repaired and stabilized effectively, the paper demonstrates that an entire roof collapse failure is highly possible in the near future to each of the five unwatered rock cavern relics. The findings presented in this paper are also invaluable both to the long-term protection and preservation of the large rock cavern relics of national and international interests and importance, and to extend and enrich our experience and knowledge on the long-term stability and integrity of man-made underground rock cavern engineering projects.This paper presents a comprehensive summary of data, analyses and findings from the investigations over the past twelve years about the relics of large Longyou rock caverns carved about 2 000 years ago at shallow depths in argillaceous siltstone. The paper presents the typical features associated with the rock caverns. They include structures, large spans, portals, extreme shallow-buried depths, imprints, drainages, inclined ceiling, inclined sidewalls, slender rock pillars, rock staircases, site and strata selections, caving lighting, carving method, and underground construction surveying. They are used to reconstruct and highlight the design and construction methods adopted by the ancients. The paper further demonstrates that the relics of the complete large rock caverns are a consequence of coincidental combinations of ancient human effort and natural factors. The full occupation of water with weak acidity in the large rock caverns with the soft surrounding rocks of weak alkalinity is found to be the main factor ensuring and preserving the caverns to have been stable and integral over 2 000 years. However, the five unwatered complete rock cavern relics have been experiencing various deteriorations and small failures including cracks, seepage, small rock falls and delaminating ceiling rocks. Although these deteriorations have been repaired and stabilized effectively, the paper demonstrates that an entire roof collapse failure is highly possible in the near future to each of the five unwatered rock cavern relics. The findings presented in this paper are also invaluable both to the long-term protection and preservation of the large rock cavern relics of national and international interests and importance, and to extend and enrich our experience and knowledge on the long-term stability and integrity of man-made underground rock cavern engineering projects.

关 键 词：rock cavern rock mechanics rock engineering long-term stability and integrity argillaceous siltstone environment 

分 类 号：TU45[建筑科学—岩土工程]