摘要：
作者近20年来在中国浙江省发现多处大型古地下工程洞室群,包括3000余个古洞室.通过现场调查发现,在这些古洞室群中,既有迄今为止所发现的最大跨度为92 m的天台县黑洞大型古地下采石场洞室,又有最大高度为99 m的长屿硐天水云硐古地下采石场洞室,还有洞壁刻凿最为华丽的龙游石窟古地下洞室.这些洞室均具有共同的特点:始采于几百年-几千年,即均保持了上千年的稳定;它们又具有各自独特的结构:斜墙、鱼尾形柱托、斜顶、穹顶、肋形仰拱,洞间隔墙,洞间水平隔板等等.研究表明,这些独特的结构均对洞室的长期稳定起到了至关重要的作用;除此之外,在这些古地下洞室群中还发现了古人高超的测量技术、开凿技术和防水技术等.这些保持了上千年稳定的无支护大跨度人工洞室群,对现代岩石力学有着诸多启示.然而,随着对这些洞室群的发现及旅游开发,各种破坏现象已经产生,严重威胁着这些古工程遗迹的稳定和安全,同时也对如何开展大跨度人工洞室群的长期保护提出了新课题和新挑战.%In the recent two decades,the authors have investigated many large underground caverns in Zhejiang, Anhui and other places in China,including more than 3 000 ancient man-made rock caverns.Through field investigations,it is found that Tiantai Heidong underground rock caverns have the largest span of 92 m, Changyudongtian caverns have the maximum height of 99 m,as well as the most exquisite chisel imprints on sidewalls in Longyou Grottoes.These caverns have the same characteristics including excavated a few hundred years to several thousand years ago,have maintained the stability of thousands of years.These caverns have their own unique structures including inclined walls,fishtail-shaped pillars,inclined roof,dome,rib-shaped arch,thin common sidewall and horizontal partition between two caverns.Research results show that these unique structures play a crucial role in the long-term stability of the caverns.In addition,there are also many high-level technologies in the ancient large underground caverns such as the measurement technology,excavation technology and waterproof technology.These groups of unsupported large-span artificial caverns,which have been maintained for more than a thousand years,provide some enlightenments of the long-term strength,the water effect on surrounding rock and the evaluation of blasting damage.However,with the discovery of these caverns and the development of tourism, various kinds of deformations and failures have been produced,posing a serious threat to the stability and security of these ancient rock cavern relics.At the same time,some new topics and challenges have been proposed for the long-term protection of large-span artificial rock caverns.
