中文摘要：

在中薄层砂岩中开挖的石窟，经常会发生顶板下沉、弯曲、冒落等病害，但顶板岩层薄片状剥落的现象不多。安徽屯溪花山谜窟对外开放后洞室顶板发生了严重薄片状剥落现象。研究表明，泥质粉砂岩的岩石结构和成份、砂岩中大量云母片沿层理方向呈定向排列及垂向上抗拉强度低均会引起洞室顶板变形破坏，开放前后环境温湿条件变化较大，顶板岩层产生大量平行于洞顶壁的片状剥落。本文着重对35号洞室顶板片状剥落物的岩石物理性质进行分析，认为因矿物的定向排列导致的结构各向异性对顶板片状剥落病害的发生起控制作用。

英文摘要：

There frequently occur roof subsidence, roof warping, and roof breaking away in Caves excavated in medium-thin bedded sandstones, but roof sheet-like peeling is rarely seen. However, it is in Huashan fiddle grottos in Tunsi, Anhui Province opening to the public that has often occurred a serious roof sheet-like peeling. These caves were excavated long time ago in sandstone and argillaceous sandstone. The sandstones contain a lot of mica oriented parallel to bedding and have a lower tensile strength, so the cave roof consisting of them is easily to be deformed and damagd. In addition, more differences in temperature and humidity before and after opening could be also a reason to roof damage. The paper focuses on analyzing physical properties of roof-peeled material in cave No. 35 of Huashan fiddle grottos and think that the roof sheet-like peeling should mainly be controlled by a structural anisotropy due to mineral orienting.