Study On Roof Stability Of Yuanjue Cave In Dazu Stone Carving

Stone carvings are immovable artifacts and occupy a large proportion.According to the statistics of 2018,there are more than 30 state-level key cultural relics protection units and 94 provincial-level protection units in the existing stone carvings and cliff sculptures in China.In the classification of cultural relics protection in China,the stone inscriptions belong to the category of immovable cultural relics,and belong to the category of "cave temples and stone inscriptions" in the classification of immovable cultural relics,juxtaposed with ancient tombs,ancient sites,ancient buildings and modern architectural histories.However,in the study and specific classification system of world cultural heritage,stone inscriptions are not classified into separate types of cultural relics protection.According to the basic types and characteristic attributes such as "ruins"," buildings" and "monuments",the cave temple,Ancient tombs,ancient ruins,ancient buildings and other buildings and stone(stone)carvings are the constituent elements of this cultural heritage classification.The sculptures completed by ancient architects and artists through stone materials reflect the culture,customs,and historical traditions of the creator’s life.Therefore,the stone carvings preserved to this day have important historical and artistic value.Compared with the cultural relics selected from wood,ceramics,bauxite and other materials,stone materials have better durability characteristics,but they are easily exposed to wind and rain due to prolonged exposure to natural environmental conditions,especially in the harsher.In natural geomorphology and geological environment,deterioration and disease of stone artifacts are inevitable.Therefore,the materials used for stone carvings are limited by the natural environment and topographical conditions.The stone has lithological change and diversity,and the environment is harsh and complicated,resulting in the preservation of stone inscriptions in the natural environment.Threat.After on-site investigation and investigation,stone carvings exposed to the natural environment generally have a series of dangerous cultural relics protection problems such as flooding,structural instability and pollution.The joint fissures around the circle of the cave are developed,and the lower layer of the bedrock is partially suspended due to the weathering and crust.Although the pile-beam structure support and the masonry filling have been done,there may still be sagging and bending moments,plus weathering.The denudation and water damage have seriously affected the stability and safety of the round cave.Numerous scientific research institutions,experts and scholars have not been able to determine their stability and finalize reinforcement technology programs after decades of research.For example,in 1996,"Baodingshan Stone Carving Dangerous Rock Disease Investigation and Rock Mass Stability Analysis"emphasized the stability of the circular sensation roof,but lacked the lithology subdivision,and did not consider the lithologic soft and hard interbed conditions and The two-dimensional plane strain calculation method is inconsistent with the three-dimensional anisotropic spatial shape of the block and the fracture.In 2012,the Chongqing Dazu Rock Carving Baodingshan Dafowan Water Damage Control Project Investigation and Research on the large-scale fracture distribution and water level in the Dazu Rock Carving Area The situation has been studied in more detail,but the stability of the circle hole has not been investigated and analyzed.The foundation of the protection work of grottoes is the comprehensive cognition of the geological bodies in which they are located.The first thing to be aware of is the material nature and structural characteristics of the geological bodies,so as to analyze the stability of the grottoes,which is largely determined.The possibility that the value of the cave cultural relics continues.In view of this,on the basis of making full use of the previous work results,this paper analyzes the stability problem of the circular sensation roof through regional geological survey,geometric feature mapping,refined survey and stable three-dimensional numerical simulation analysis,and finally based on the research results.Provide preliminary reinforcement and treatment suggestions for the round hole,and provide a scientific basis for stability management.The main research contents include the following four aspects:1.Regional geological survey:Identify the environmental geology,engineering geology,hydrogeology and geology in the surrounding area of Yuanjue Cave.2.Investigation and evaluation of roof rock mass stability:Identify the geometric characteristics of the circle cave,identify the lithology of the stratum,the stratum structure,and evaluate the stability of the roof.3.Establish a geomechanical model of the circular sensation roof and evaluate the three-dimensional numerical stability.4.Monitoring the stability of the roof of the round hole.As a result,it is concluded that the roof of Yuanjue Cave is uneven,which is supported by four areas:the filling area of the east side of the window,the triangle area of the back wall,the filling area of the west side of the window and the triangle area of the west side of the window.there is the phenomenon and development trend of stress concentration,as well as the risk of roof separation,and it is concluded that relevant measures should be taken as soon as possible.