ML13329A716
| ML13329A716 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/12/1983 |
| From: | Southern California Edison Co |
| To: | |
| Shared Package | |
| ML13310A945 | List: |
| References | |
| TASK-02-04.F, TASK-2-4.F, TASK-RR NUDOCS 8309070428 | |
| Download: ML13329A716 (6) | |
Text
ENCLOSURE 2 ADDENDUM 1 TO REPORT ON SOIL BACKFILL CONDITIONS SAN ONOFRE NUCLEAR GENERATING STATION UNIT 1 JULY 12, 1983 8309070428 830901 PDR ADOCK 05000206 P
ADDENDUM 1 TO REPORT ON SOIL BACKFILL CONDITIONS This addendum provides additional information regarding the insitu backfill soil conditions which was not included in Chapters 1 to 3 and the appendices of the report on this matter. Specifically, this addendum provides (1) additional results of soil density tests and observations of footing conditions made at the site;
- 2) a discussion of the use of 85 percent relative compaction as a minimum average at the site.
Additional Test Data and Observations The results of additional tests made in the backfill at the site are given in Table 1. The additional data are in the south extension of the Turbine Building and outside area pipe trench excavations. In addition, the following observations have been made:
a)
In reviewing the results of the tests given in Table 1, it was noted that soil backfill exposed in the Footing F excavation in the south extension of the Turbine Building shows several tests in the range of 81 to 87 percent relative compaction. The excavations also revealed the remnant of an old dewatering well (loose soil and gravel pack), the location of which is in general agreement with the construction photographs of the site. Some of the tests are low due to their proximity to the dewatering well backfill. Based on these test results and an inspection of the footing excavation, the soil characterization in this area has been modified locally from Category B to Category D soil fill.
This change is reflected in the attached revised Figure 2-22.
b)
Review of additional observations made in December 1980 for the foundation for the dog house structure north of the Ventilation Equipment Building showed that the backfill beneath the west wall of the Ventilation Equipment Building is less than what was previously indicated in Section 2 of the report.
It should be noted that the above data are not reflected in the figures in sections 2 and 3 and the appendices of the Soil Backfill Conditions report.
However, they are considered in section 4 and 5 of the report and in this addendum.
Discussion of 85 Percent Relative Compaction Charactarization A density of 85 percent average relative compaction was used to characterize Category D fills as well as deep/narrow portions of Category B and C fills as shown in Figure 2-22. The relative compaction of the fill is an important parameter which is used as basic input to the evaluation of seismically induced settlements.
Case histories indicate that the amount of seismically induced settlement for a sandy soil deposit can be calculated using the average density of the deposit.
The selection of the average value in this case was based on inspection of density test results for fill soils. For such fills a mean value of relative compaction for all tests on fills is about 89 percent with a standard
deviation of 5 to 6 percent. These observations represent all categories of fill. Perhaps the most representative area to evaluate the average density of deep narrow fills is the backfill which was tested adjacent to the east side of the Fuel Storage Building. In that area, 11 tests were made in backfill between elevation +5 feet and +13 feet. These tests showed a mean relative compaction of between 85 and 86 percent and a standard deviation of 4 percent. It was not possible to obtain test results below elevation +5 feet in this area due to the congested nature of the excavation below that elevation. To evaluate the effect of elevation on relative compaction, the 175 tests taken on backfill between elevation 0 and 20 were statistically analyzed at 2-foot intervals. These tests were selected from density tests documented in Table B-1 of the soil conditions report and Table 1 of this addendum. It is noted that only those tests representing existing backfill were utilized. The calculated mean and mean minus one standard deviation of the available data are plotted in Figure 1 along with all data points for each interval. Also shown for reference is the mean and mean minus one standard deviation for all tests in the depth range.
As shown by Figure 1, the overall mean and mean minus one standard deviation are about 89 and 83 to 84 percent relative compaction, respectively. The corresponding two-foot interval results and the distribution of data points show no specific trend with elevation. Further, as shown in Figure 1, 85 percent relative compaction corresponds to 50 percent relative density while 80 percent relative compaction corresponds to 30 percent relative density. It is considered unlikely that a soil deposit could remain at 30 percent relative density areally in a location such as the SONGS site where vibrations due to the operation of the power plant equipment or construction equipment have been almost continuous for over 15 years.
Based on the aforementioned observation, the results of the 11 tests obtained at the east end of the Fuel Storage Building and on the lack in trend of density with elevation shown in Figure 1, it is concluded that 85 percent relative compaction is the appropriate value for use in settlement calculations.
TABOjC 0 OODARDCL CONSULTANTS Job Name:
SONGS 1 Field Data Sheet Sheet No.:
19 Job Number:
41009K(
SEISMIC MODIFICATIONS SHORT TERM OUTAGE PROJECT Field Dry Max.
Rel. Spec Drawing Test Retest Retest Grid Density Moist.
Lab. Comp Reg. No.,
Quality Date Number by of Number Location of Test Elev. (pcf)
(pcf) %
Spec. Class 12+8 Fill M-N-8 See Plot Jan 24 711 W4+99 Turbine Bldg. Ftg. ""+14.'
97 4
S1 :
120 81 95 Plan 2
S12+94 Fill N-9 Jan 24 712 W5401 Turbine Bldg. Ftq.
" " +16.
100 6
83 T81+79 Fill M-8 Jan 26 713 W4+93 Turbine Bldg. Ftq. " "
+11' 98 5
82 o"
S12+99 Fill N-8 Feb 3
714 W4+93 Turbine Bldg. Ftq. " "
+16' 98 3
.L S11+71 Fill Trench Feb 3
715 W5+42 Turbine Bldg. Piping
+17.
103 4
86 S11+84 Fill Trench Feb 3
716 W5442 Turbine Bldg. Piping
+17.
104 5
86 S11+96 Backfill, E. side Feb 7
717 W5+72 Piping Trench Overcu
+11.
115 9
96 511+72 Backfill, N. side Feb 7
718 W5+72 Piping Trench Overcu
+12' 115 9
9L S12+72 Native Feb 8
719 W5+72 Waste Oil Line S.G.
+11' 120 5
100
- 2 S13+36 Native Feb 8 720 W5+71 Waste Oil Line S.G.
+12' 120 4
2 1W S13+40 Fill Feb 9
721 726 W5467 Waste Oil Line S.G.
+12' 100 5
3 3
- 2 S12+96 Native Feb 11 722 W5406 Turbine Bldq. Fty.
+16' 120 4
1 S12+99 Native Feb 11 723 W4+97 Turbine Bldg. Ftq. " "+14,'
119 9T 99
- 7 S12+78 Fill M-8 Feb11 724 W4+94 TurbineBldg.
9..92'
.y S13+62 Native Feb 15 725 W5+38 Waste Oil Line S.G.
+14 I.1 4
01
"."."Z*
Remarks: *2 Test.reqqgsted by Bechtel Class 1 & 2 Reviewed By:
Class 3 & 4 Reviewe& By:
TABVh IOODWARD-C CONSULTANTS Job Name:
SONGS. 1 Field Data Sheet Sheet No.:
20 SEISMIC MODIFICATIONS SHORT TERM OUTAGE PROJECT Job Number:
41009K Field Dry Max.
Rel. Spec Drawing Test Retest Retest Grid Density Hoist.
Lab. Comp Reg. No.,
Quality Date Number by of Number Location of Test Elev. (pcf)
(pcf) %
Spec.
Class S13+39 Backfill See Plot Feb 24 726 721 4568 ste Oil Line S.G.
+12' 117 5
3/d 120 97 95 Plan 2
- 2 512+77 Fill Feb 24 727 403 bine Bldg. Ft.
"I 8.5 97 8
"1 "1
81 "o
so
- 2 512+98 ative Feb 26 728 402 Tbine_
lg.
- a.
+14.5 120
- 4.
_100.
"*2 912+61 FillSo to 9gofof Mar 3
729
_5+71 1 " Eve Wash.Line
+12' 109 7
"L 512+52 Fill Mar 3 730 5+71 IS" En Wash Line
+12 '
I93
"*2 512+77 Fill, Drain Line Mar 3
731 44+90 rurineBldq.
aq."I" 7'
I 6
RT 7_
R3 312+90 Bckfill Mar 7
732 733
_5+72 i
Waste Line
+13' 110 6
2 "t
"o
- 2 512+93 Bckfill Mar 7
733 732 5+72.
I Waste Lineoom
+13' 114 R
"f f
9 "f
513+42 Bckfill Mar 8
734
_5+55 il Waste Line
+195 118 10 98 "f"
- 2 313+37 Bckfill Mar 8
735
_5405 Level Indicator Line
+1' 1-17 a
98 R-
"f "i
13+13 Bckfill Mar 9
736 5403 evel Indic atr Line
+19'11 1o94
- 2 512+87 Bckfill Mar 11 737 739
_3+18 r Line Lateral
+181 Il 7
9o 9t92.
11+95 ckfill Mar 11 738 q1+78 r Line Lateral
+22' 116 9
312+87 Bckfill Mar 11 739 737 V3+18 Sewer Line Lateral
-+15
.96-Remarks a *2 Test reaested y Bechtel Class 1 & 2 RevieweK By:
Class 3 &
4 Reviewer By:
Relative Density, %
0 30 50 60 70 80 90 100 Relative Compaction, %
Number 75 80 85 90 95 100 ofTests I
I II overall mean - 10 overall mean mean - 10 mean
+20
/
.1 e
e e
8
.2.
40 131 I
4-e e
- S *
+5 -
- 9
- 1 0
2 NII
- oa
- ube of
- est 115 Project: SEISMIC RE-EVALUATION SMAYO ECN EAIEFg Project No.
413521 COMPACTION AS A FUNCTION OF ELEVATION I
WOODWARD-CLYDE CONSULTANTS