Prediction-Based Maintenance of Existing Bridges Using Neural Network and Sensitivity Analysis

Table 2

Inspection grades and corresponding conditions of bridges.

Grade	Conditions	Descriptions
1	Healthy	A state that the function of the structure is not disturbed.
2	Preventive action required	Although the function of the structure is not hindered, it is desirable to take measures from the viewpoint of preventive maintenance.
3	Early action required	The function of the structure has interfered and measures should be taken as soon as possible.
4	Emergency action required	A condition in which the function of the structure has been or is likely to be impaired, and measures should be taken urgently.