ML20033D334
| ML20033D334 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 12/03/1981 |
| From: | Geier J ILLINOIS POWER CO. |
| To: | John Miller Office of Nuclear Reactor Regulation |
| References | |
| U-0379, U-379, NUDOCS 8112070538 | |
| Download: ML20033D334 (3) | |
Text
{{#Wiki_filter:-- s 8. U-0379 ILL/NOIS POWER 00MPANY L30-81 (12-03)-6 500 SOUTH 27TH STREET, DECATUR, ILLINOls 62525 December 3, 1981 Mr. James R. Miller, Chief . \\ gg Mf'/ Standardization & Special Projects Branch \\ Division of Licensing 'f Office of Nuclear Reactor Rcgulation /7 /q, L U. S. Nuclear Regulatory Commissitn ggC [ ${ Washington, D. C. 20555 g_ p, g ISg/ A
Dear Mr. Miller:
4 Clinton Power Station Unit 1 h'/ ),a Docket No. 50-461 In response to Mr. B. Jagannath's, HGEB reviewer, questions on settlement of Unit 1 due to Unit 2 construction, we are submitting the enclosed material. Sincerely, (. 'J.D. Geier Manager, Nuclear Station Engineering Attachments cc: J.H. Williams, NRC Clinton Project' Manager H.H. Livermore, NRC Resident Inspector B. Jagannath, NRC HGEB of 1 4 /00: 3, he# VAN 8112070538 8 -{DRADOCK05 y_* 3.. ~ ui:
~-a x 7j ' sa CLINTON STATION CLARIFICATION ON PLANT SETTLEMENT -1. What are the elastic settlements of the structural fill under Unit 1 due to loads from Unit 2 when constructed at a later date?
Response
.The maximum elastic settlement of the structural fill under Unit'l due to Unit 2 construction at a later date is estimated to be 0.02 inches. 2. Provide a time-dependent tuttlement plot of the till layer under Unit I due to loads from Unit 2 when ;onstructed at a later date.
Response
The attached Figure 1 shows the settlement vs. time plot for the till layer under the radwaste building, which will be most affected by the loads from Unit 2. The final settlement is estimated to be 0.72 inches. 3. Provide a quantitative assessment of the short-term'(initial) settle-ment of the till layer under Unit 1 due to the load from Unit 2 when - constructed at a later date.
Response
.The initial. settlement of a saturated cohesive material may be defined as - the. settlement during undrained condition, which is ' generally very 1 small compared to the total settlement which accounts for the drained condition (consolidation settlement) It is_not possible to separatej ott the initial settlement and consolidation settlement in cases where the loading is also a time variant. However, a quantitative assessment-has been made using elastic theory and the elastic modulus corresponding to the compression wave velocity:in water (undrained condition). Based on this approach, the. maximum initial settlement in the till layer under. . Unit 1 is computed as' O.03 inch. 4. What is the incremental increase in settlement between Unit l-and ~the buried pipes under Unit 1 due to loads from Unit 2 when constructed at a later date; evaluate itsreffect on the~ design of'the-buried _ pipes..
Response
The. maximum incremental settlement between Unit 1 and the buried pipes-under Unit 1 due!to loadsifrom Unit 2 when constructed'at a later date
- is' estimated.to be 0.5 inches.
It may-be noted that the buried pipes: .under_. Unit 1 are designed for a ' differential settlement of 1-~1nch be-tween buildings and the pipes _(see response ~to; Question 241.8), which includes this 0.5: inch settlement. w N .n. m m .2...I ..5 m. m. .I& .. EM
CLIETON rG SR STATION ~ 4 4 TINE (YEARS) O. O~ 10 15 20 S 1 .72 inch 25 w g-9 i5 2 '- t
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- 3-Figure.1 Time va, Settlement for Till Layer'under Radwaste Building (at a Location Close to Unit 2} due to Constrdction of Unit 2 at a Later Date o
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