ML16054A436
| ML16054A436 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 01/26/2016 |
| From: | Northern States Power Co, Xcel Energy |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16054A376 | List:
|
| References | |
| L-MT-16-004 | |
| Download: ML16054A436 (49) | |
Text
A.4-1 Rev. 28 MONTICELLO NUCLEAR GENERATION PLANT REACTOR PRESSURE VESSEL SEISMIC ANALYSIS INTRODUCTION The purpose of this report is to summarize the results of the seismic investigation of the Monticello Nuclear Generation Plant Reactor Pressure Vessel. Based on the recommended earthquake design criteria 1, design envelopes of maximum acceleration, displacement, moment and shear have been developed and are presented herein. In addition, the response of the reactor pressure vessel to the jet load reactions has also been determined and is presented.
Some minor differences exist between the known RPV component weights as compared to those used in this analysis. The differences result in a net decrease in weight that is a small percentage of overall system mass. Therefore, Monticello recognizes this analysis as providing conservative results for the RPV seismic response.
DESCRIPTION OF REACTOR PRESSURE VESSEL The reactor pressure vessel consists of a 63' - 2" long cylindrical shell having an inside diameter of 17' - 1". It is supported by concrete pedestal through steel skirt.
Lateral support is provided by stabilizers between reactor pressure vessel and shield wall at El. 994' - 2". A truss consisting of 16' - 10" XXS pipes between shield wall and reactor building laterally support the shield wall at El. 992' - 51/2". Geometric relation between reactor pressure vessel, shield wall, pedestal wall and reactor building is shown in Appendix A, Sheet 1.
MATHEMATICAL MODEL OF REACTOR PRESSURE VESSEL The entire Monticello reactor structure (i.e., building, drywell, pressure vessel and shield) was mathematically modeled as a 27 mass coupled system. The system couples model described in previous report2 with the shield wall, reactor pressure vessel and pedestal wall. The mathematical model is shown in Appendix A, Sheet 2.
ANALYTICAL PROCEDURES PERIODS AND MODE SHAPES Subsequent to the formation of mass and stiffness matrices for the coupled system, the periods and mode shapes are calculated by solving for the eigenvalues and eigenvectors of Equation (1). 01245382
A.4-1 Rev. 28 MONTICELLO NUCLEAR GENERATION PLANT REACTOR PRESSURE VESSEL SEISMIC ANALYSIS INTRODUCTION The purpose of this report is to summarize the results of the seismic investigation of the Monticello Nuclear Generation Plant Reactor Pressure Vessel. Based on the recommended earthquake design criteria 1, design envelopes of maximum acceleration, displacement, moment and shear have been developed and are presented herein. In addition, the response of the reactor pressure vessel to the jet load reactions has also been determined and is presented.
Some minor differences exist between the known RPV component weights as compared to those used in this analysis. The differences result in a net decrease in weight that is a small percentage of overall system mass. Therefore, Monticello recognizes this analysis as providing conservative results for the RPV seismic response.
DESCRIPTION OF REACTOR PRESSURE VESSEL The reactor pressure vessel consists of a 63' - 2" long cylindrical shell having an inside diameter of 17' - 1". It is supported by concrete pedestal through steel skirt.
Lateral support is provided by stabilizers between reactor pressure vessel and shield wall at El. 994' - 2". A truss consisting of 16' - 10" XXS pipes between shield wall and reactor building laterally support the shield wall at El. 992' - 51/2". Geometric relation between reactor pressure vessel, shield wall, pedestal wall and reactor building is shown in Appendix A, Sheet 1.
MATHEMATICAL MODEL OF REACTOR PRESSURE VESSEL The entire Monticello reactor structure (i.e., building, drywell, pressure vessel and shield) was mathematically modeled as a 27 mass coupled system. The system couples model described in previous report2 with the shield wall, reactor pressure vessel and pedestal wall. The mathematical model is shown in Appendix A, Sheet 2.
ANALYTICAL PROCEDURES PERIODS AND MODE SHAPES Subsequent to the formation of mass and stiffness matrices for the coupled system, the periods and mode shapes are calculated by solving for the eigenvalues and eigenvectors of Equation (1). 01245382