Experimental Study On Disease Characteristic And Dissolution Mechanism Of Limestone In Guihai Forest Of Steles

Guilin Beilin is a national key cultural relics protection unit and the most concentrated and typical place of Guilin stone carvings.Due to the long-term exposure of stone in the natural environment,it has suffered from different degrees of weathering.In this paper,the stone carvings of the Stone Forest in Guihai were taken as the research object.The types of stone carving diseases,the disease area and the causes of water disasters were investigated.The degree of stone carving disease and its influencing factors were analyzed.The dissolution test of limestone was studied to study the disease characteristics and dissolution mechanism.The main research work and results of this paper are as follows:(1)Water quality testing of river water and water seepage in the study area indicates weak alkaline or neutral.The mineral chemical composition and physical and mechanical properties of the limestone samples were tested.The results show that the limestone is a granitic limestone with few pores and compact structure.(2)Statistical analysis was carried out on the types and extents of 191 stone carving diseases,disease areas and diseases.The results showed that the types of stone carving diseases were mainly microbes,local missing,surface flaking,erosion,rust crust,and human pollution.According to the correlation analysis between the disease area and the severity of the disease,it is shown that the erosion caused a large damage on the surface of the stone carving.According to the analysis results of water seepage,slope rainwater,condensed water and stone carving type and degree,it is shown that the stone intrusion affected by water seepage and slope rain is most likely to cause erosion,which is more destructive to stone carving.(3)10 times of rain cycle test(1200 hours)were carried out on the granule limestone test block,and the surface topography,mass loss and wave velocity properties of the test block were measured after each cycle.Studies have shown that under the action of kinetic water(rain),the calcite matrix on the surface first melts,and then the granules fall off.Then,the calcite matrix continues to slowly dissolve,waiting for the next breakout.During this process,no degradation occurred inside the test piece.