Considering the functional decline of the river and the basic characteristics of function of maintenance of the river.

Abstract

For formalize the characteristics of the functional decline of the river, we organized the basic characteristics of the function and its degradations of the river for practice of river administrator.

Also, this report is to illustrate the characteristics using examples of past disaster and inspection results, and consider the perspective to take a comprehensive and panoramic view of river rather than capturing the function and state for each structure, meaning and issues of affairs which understands the state of river, future areas of technology development.

In addition, using the concept of performance specified in such as "general principles of reliability of the structure" ISO2394, we studied the introduction of acceptable level against degrading rivers, and organized the check methods and empirical knowledge which is necessary to judge it.