Risk Analysis Preventive Protection Of Salt Weathering Based On The Stone Bell Mountain Grottoes In Jianchuan

The Jianchuan Stone Bell Mountain Grottoes,located in the southwestern border,are highly preserved.According to the investigation,salt damage is the main disease risk that threatens the long-term preservation of the Stone Bell Mountain Grottoes.It is of great practical significance to analyze and evaluate the salt weathering risk level and give corresponding protection suggestions.For stone cultural relics,salt weathering is the main factor for their body to be destroyed.The pore structure inside stone cultural relics is complex.In groundwater environment or salt spray environment,the internal pores of stone cultural relics will generate salt due to infiltration and capillary rise.For the retention of solution,it is generally believed that larger pores are the channels for the salt solution to enter the interior of the body,and smaller pores will retain the salt solution,but the change of the concentration difference between the pores is dynamic,which means that the body pores’ salt crystallization activities during internal sub-weathering are active and complex.Through a large number of long-term studies,scholars have found that the salt weathering mechanism of porous materials is closely related to the porosity,pore size distribution,pore size and other parameters of porous materials under a certain temperature and humidity,and the theory of salt crystallization stress has also been discussed in depth.In order to have a deeper understanding of the sub-weathering effect of salt crystallization on stone cultural relics and solve the problem that the evaluation index of salt weathering degree in the protection project of stone cultural relics is not pertinent,this paper proposes that rock micropores absorbing salt strength coefficient on the basis of previous research,established a theoretical model that can explain the law of salt crystallization in a complex porous system,revised the salt crystallization pressure formula through theoretical derivation,and put forward the speed of salt entering into rock micropores for quantitative analysis of the risk of salt weathering and the degree of salt weathering in rock cultural relics.Degree Index(SSPN)and Rock Salt Weathering Risk Index(SWRI).The salt weathering risk analysis of the Jianchuan Stone Bell Mountain Grottoes was carried out by combining the rock salt sensitivity index(SSI),the speed and slowness index of rock micropores(SSPN)and the corrected crystallization pressure.It also provides preventive protection suggestions for building a micro-environment monitoring system for the Stone Bell Mountain Grottoes,carrying out the digitization of the Stone Bell Mountain Grottoes,and regularly assessing the risk of salt weathering in the grottoes.