Optimization And Assessment Of The Protective Shed Of The Eastern Wu Tomb For Biodeterioration Control

As one of the world’s four ancient civilizations,China has a long history and a large number of brick and stone architectural sites,which bear important historical and cultural information.Due to the fluctuation of environmental factors,the brick and stone sites are prone to biodeteration,which will bring chemical,mechanical and also apparent damage to the site and threaten the heritage value.Microbial spores are ubiquitous in the air and tend to adhere to material surfaces exposed to air.Once the temperature,humidity,nutrients and other conditions are suitable,microbial spores adhered on material surfaces will be "activated" and microorganisms began to colonize and multiply.At present,in the field of heritage conservation,the measures for inhibiting biodeteration are mostly surface cleaning and sterilization,which are " addressing the symptoms,not the cause" from the perspective of mechanism of microbial growth and reproduction.The brick and stone archaeological sites are directly connected with the ground,which are susceptible to the influence of groundwater and the rising damp.At the same time,the open environment of the site brings continuous evaporation and fluctuation of temperature and humidity,which lead to local condensation on the surface of the sites,high water content of the material in the sites,and then provide a favorable environment for the colonization and growth of microorganisms.Starting with the site’s dependent environment,this study takes the Eastern Wu tomb in Nanjing as an example and brings forward adding a functional space to the existing protective shed.The functional space can absorb solar radiation and transfer solar energy to the tomb through heat conduction or air exchange,then change the site’s dependent environment and reduce the dew on the site’s surface and fundamentally inhibit the deterioration of microorganisms through environmental regulation.Firstly,this paper investigated and sort out the recent status and the environmental causes of microbial deterioration in the Eastern Wu tomb in Shangfang.Secondly,Fortran program was used to establish a numerical analysis model for hygrothermal transfer in the Eastern Wu tomb and an environmental evaluation system was established for biodeteration.Then,from the perspective of environmental regulation,the paper brought forward the plan of adding a functional space and optimized the existing protective shed.Finally,by comparing and analyzing the simulation results of hygrothermal transfer before and after the addition of the functional space,the paper evaluated the dependent environmental changes around the Eastern Wu tomb brought by the addition of the functional space and its effectiveness in inhibiting biodeteration.The functional space proposed in this study is a simple,economical and nearly passive environmental control system with no long-term management cost,which is very important for conservation management.Adding a functional space is a method of inhibiting biodeteration based on environmental regulation,which has a lasting effect on inhibiting biodeteration by improving the physical environment around the site.It is an active exploration for inhibiting biodeteration in the field of heritage conservation,and provides a reference strategy for the protection of other similar sites to control biodeteration.At the same time,this study uses numerical model to study hygrothermal transfer in the environment of architectural heritage and establishes a scientific evaluation system for the biodeteration,which provides strong scientific support for the heritage conservation work and promotes the application and progress of heritage protection technology.Words: 49,400;Figures and tables: 122.