Abstract
This paper attempts to improve a fuzzy expert system which was developed previously to help maintenance engineers to evaluate the damage state of reinforced concrete bridge deck. One of important items in the maintenance program is that the repairing methods are automatically selected. The present system can provide several appropriate repairing methods by taking account of the damage cause, damage degree, and damage propagation speed. Since the system is built on a 32 bit engineering workstation and is written with Common Lisp, anyone can use this system without difficulty. Furthermore, adding the ability of executing backward reasoning in the procedure of fuzzy inference, it is possible to reduce the computation time to a quarter of that required for the previous system.
