The effect of the soft decay destructive effect on the historical wooden doors made of the plane located in Beit-o-Lahm church in Isfahan

Wood is one of the raw materials used in the monument of Beit-o-Lahm church in Isfahan. The wooden door is in the altar of the church and the door opens to the cellar. The wooden door is made of plane and soft decay by fungi has decreased its strength. The purpose of the research is to examine the destructive effects of soft decay for reducing the strength of the historical wooden door made of plane in the cellar of the altar of Beit-o-Lahm church in Isfahan. In addition, physical, chemical, and mechanical strengths and structural changes of the wooden door are evaluated. For this purpose, documentation, statistical software, experimental studies, microscopic observations and FTIR and SEM are used to examine the chemical changes of the wood structure and morphological observations of the wood surface under the soft decay by fungi. The results of the tests show that fungi in the structure of the plane wood have destroyed the cell walls, increased the moisture, decreased density, cellulose and lignin and finally, they have declined the bending strength, compressive strength and impact strength and have reduced the resistance of the wood. The lack of the strengths has destroyed the historical wooden door