EVALUATION TEST METHOD FOR DEGRADATION OF INCORE STRUCTURE MATERIAL

PROBLEM TO BE SOLVED: To properly diagnose and evaluate the degradation of incore structure materials, by inserting test pieces for material degradation evaluation in the core in advance, and testing directly the material characteristics using the test pieces. SOLUTION: In the case test pieces for evaluation is attached in the core in advance, the test pieces are taken out and material evaluation test is conducted. In the case test pieces for evaluation are not attached, the attaching position of the test piece for evaluation, test piece shape, etc., are examined. In the case, for example, evaluating the material characteristics of jet pump material, the test pieces for evaluation are attached in the hole of hanging jig used for attaching pumps during construction. A test piece container 11 completely sealed after inserting the test piece for evaluation 10 made of the same material as the pump is passed through the hole of the hanging jig 2, by using a monitoring camera or remote operation robot and operating a guide wire 20 and the like and fixed. The test pieces for evaluation 10 is taken out, if it has a shape capable of evaluating, and is transported to a hot laboratory and directly tested.