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Revised Proposed Tech Specs 3.6.1.6, Containment Structural Integrity
	ML20052F477
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Site:	Summer
Issue date:	05/05/1982
From:	; SOUTH CAROLINA ELECTRIC & GAS CO.
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ML20052F474	List: ML20052F473; ML20052F477;
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	NUDOCS 8205130058
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CONTAINMENT SYSTEMS CONTAINMENT STRUCTURAL INTEGRITY LIMITING CONDITIONS FOR OPERATION 3.6.1.6 The structural integrity of the containment shall be maintsined at a level consistent with the acceptance criteria in Specification 4.6.1.6.

APPLICABILITY: MODES 1, 2, 3 and 4.

ACTION:

a.

With the structural integrity of the containment not conforming to the requirements of Specification 4.6.1.6.1.b, perform an engineer-ing evaluation of the containment to demonstrate the acceptability of containment tendons within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ; ~otherwise, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b.

With the structural integrity of the containment otherwise not conforming to the requirements of Specification 4.6.1.6, in lieu of any other report required by Specification 6.9.1, prepare and submit a Special Report to the Commission pursuant to Specifica-tion 6.9.2 within 30 days describing the tendon condition, the condition of the concrete (especially at tendon anchorages), the inspection procedures, the tolerances on cracking, and the corrective actions taken.

SURVEILLANCE REQUIREMENTS 4.6.1.6.1 The structural integrity of the containment tendons shall be demon-strated at the end of one, three and five years following the initial containment structural integrity test and at five year intervals.thereafter. The structural integrity of the tendons shall be demonstrated by:

a.

Determining that for a representative sample

of at least 15 tendons (4 dome, 5 vertical and 6 hoop) each has a lift off force greater than or equal to its Lower Limit indicated in Table 4.6-la.

If the lift off force of a selected tendon in a group lies between the prescribed Lower Limit and 90% of the Lower Limit, one tendon on each side of this tendon shall be checked for its lift off force.

If the lift off forces of the adjacent tendons are greater than or equal to their Lower Limits in Table 4.6-lb, the single deficiency shall be considered I

For each inspection, the tendons shall be selected on a random but representa-t tive basis so that the sample group will change somewhat for each inspection; however, to develop a history of tendon performance and to correlate the observed data, one tendon from each group (dome, vertical, and hoop) may be i

kept unchanged after the initial selection.

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9205130050 820505 PDR ADOCK 05000395 3/4 6-8 PDR l

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CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) unique and acceptable.

For tendon (s) not conforming to these requirements, a determination shall be made as to the cause of the occurrence and the tendon (s) shall be restored to the required level of integrity.

If the lift-off force of the selected tendon lies below 90% of the pre-scribed Lower Limit, the tendon shall be completely detensioned and a determination made as to the cause of the occurrence, b.

Determining that the average of the Normalized Lift Off Forces for each tendon group (vertical, dome and hoop) is greater than or equal to the minimum required average tendon force for the group. The minimum required average tendon force is 1195 kips for vertical tendons, 1115 kips for dome tendons, and 1181 kips for hoop tendons. The Normalized Lift Off Force for a tendon is obtained by adding the Normalizing Factor appearing in Table 4.6-2 to the lift off force.

Failure to comply with this requirement may be evidence of abnormal degradation of the containment structure.

If the Normalized Lift-Off Force of any tendon is less than the applicable minimum required average tendon force, an investigation shall be cot. ducted to determine the cause and extent of occurrence. This investigation shall includa as a minimum the measurement of lift-off forces of tendons adjacent to the deficient tendon to determine if the average of the tendon lift-off forces in this region of the containment is equal to or greater than the minimum required average tendon force.

Failure to comply with this require-ment may be evidence of abnormal degradation of the containment structure.

Detensioning one tendon in each group (dome, vertical and hoop) from the c.

representative sample. One wire shall be removed from each detensioned tendon and examined to determine:

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l.

That over the entire length of the tendon wire, the wire has not undergone corrosion, cracks or damage to the extent that an abnormal condition is indicated.

l 2.

A minimum tensile strength value of 240,000 psi (guaranteed ultimate strength of the tendon material) for at least three wire samples (one from each end and one at mid-length) cut from each removed wire.

l d.

Determining for each tendon in the above representative tendon sample, that an analysis of a sample of the sheathing filler grease is within the following limits:

1.

Grease Voids

[ 5% of net duct volume 2.

Chlorides y[ 10 PPM 3.

Sulphides

< 10 PPM 4.

Nitrates j! 10 PPM 5.

Water Content

< 10% by weight 3/4 6-9

I CONTAINMENT SYSTEMS

' SURVEILLANCE REQUIREMENTS (Continued)

If the inspections performed at 1, 3, and 5 years indicate no abnormal degradation of the tendon system, the number of sample tendons may be reduced to 3 dome, 3 vertical, and 3 hoop for subsequent inspections. Upon the completion of the five year inspection, the results of the first three inspections shall be evaluated to determine if an abnormal condition is evident for the tendon system. Based on the conclusions of this evaluation, the sample tendons and their Lower Limit Values will be specified for all subsequent inspections.

4.6.1.6.2 At the same inspection frequency as the tendons, the structural integrity of the end anchorages of a11' tendons inspected pursuant to Specification 4.6.1.6.1 and the adjacent concrete surfaces shall be determined by a visual inspection and verifying that no abnormal material or structural behavior is. evident..

4.6.1.6.3 At the same inspection frequency as the Type A containment leakage rate test, the structural integrity of the exposed accessible interior and exterior surfaces of the containment shall be determined prior to each Type A containment-leakage rate test (Specification 4.6.1.2) by a visual inspection of these surfaces and verifying that no abnormal material or structural behavior is evident.

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r-I TABLE 4.6-la TENDON FORCE ACCEPTANCE CRITERIA SURVEILLANCE TENDONS INSPECTION PERIOD 1

2 3

Tendon Lower Limit (kips)

D-104 1251 D-125 1208 D-108 1260 D-129 1222 D-219 1233 D-121 1202 D-219 1241 D-228 1250 D-219 1228 D-328 1262 D-324 1249 D-312 1245 V-23 1303 V-23 1294 V-23 1288 V-46 1282 V-30 1262 V-37 1275 V-67 1307 V-53 1289 V-60 1269 V-92 1273 V-76 1288 V-83 1287 V-115 1296 V-99 1280 V-106 1273 3AC 1295 3AC 1287 3AC 1280 8BA 1250 13BA 1258 8CB 1230 13CB 1260 18CB 1240 18BA 1230 28CB 1242 28BA 1239 28AC 1238 38AC 1232-33CB 1257 33BA 1252 38BA 1230 36AC 125Y.

38CB 1211 -

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A TABLE 4.6-lb TENDON FORCE ACCEPTANCE CRITERIA ADJACENT TENDONS INSPECTION PERIOD 1

2 3

Tendon Lower Limit (kips)

D-103 1225 D-124 1259 D-107 1217 D-105 1229 D-126 1238 D-109 1198 D-128 1271 D-218 1260 D-120 1256 D-130 1242 D-220 1262 D-122 1237 D-218 1272 D-227 1247 D-218 1253 D-220 1273 D-229 1211 D-220 1257 D-327 1222 D-323 1230 D-311 1240 D-329 1214 D-325 1204 D-313 1212 V-22 1281 V-22 1275 V-22 1270 V-24 1292 V-24 1284 V-24 1280 V-45 1285 V-29 1278 V-36 1262 V-47 1300 Vv31 1300 V-38 1269 V-66 1283 V-52 1288 V-59 1282 V-68 1284

.V-54 1273 V-61 1282 V-91 1286 V-75 1280 V-82 1273 V-93 1302 V-77 1289 V-84 1278 V-114 1289 V-98 1256 V-105 1271 V-1 1290

'V-100 1273 V-107

'~1281 2AC 1257 2AC 1248 2AC 1242 4AC 1239 4AC 1230 4AC 1223 7BA 1296 12BA 1243 7CB 1272 9BA 1267 14BA 1239 9CB 1257 12CB 1260 17CB 1249 17BA 1233 14CB 1250 19CB 1262 19BA 1262 27CB 1254 27BA 1264 27AC 1268 29CB 1257 29BA 1248 29AC 1231 37.AC 1260. -

32CB 1237 32BA

-1230 39AC 1272 _,

34CB 1211 34BA 1229 37BA 1273 35AC 1270 37CB 1252 39BA 1250 37AC 1250 39CB 1262 3/4 6-10b

e TABL: 4.rd NORMALIZING FACTORS (N.F.)'

7 INSPECTION PERIOD l

1 2

3 Tendon N.F.

(kips)

Tendon N.F.

(kips)

Tendon N.F. (kips)

D-104

-24 D-125 36 D-108 D-129 33 D-219 10 D-121 40 D-219 10 D-228

-28 D-219 10 D-328

-21 D-324

-12 D-312 V-23

-15 V-23

-15 V-46 11 V-30 31 V-37

-5 V-67

-21 V-53

-24

~

V-60 11 V-92 25 V-76

-11 V-83

-15 V-115

-10 V-99 5

V-106 7

3AC

-56 3AC

-56 8BA 18 13BA

-26 8CB 26 13CB

-23 18CB 29 18BA 34 28CB 26 28BA 17 28AC 10 3BAC

- 40 33CB

-17 33BA

-16 38BA 40 36AC

.". 0 38CB 54 I

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CONTAINMENT SYSTEMS BASES 3/4.6.1.6 REACTOR BUILDING STRUCTURAL INTEGRITY This limitation ensures that the structural integrity of the containment will be maintained comparable to the original design standards for the life of the

facility, Structural integrity is required to ensure that the containment will withstand the maximum pressure of 47.1 psig in the event of a steam line break accident. The measurement of containment tendon lift off force, the tensile tests of thef tendon wires, the visual examination of tendons, anchorages and exposed interior and exterior surfaces of the containment, and the Type A leakage test are sufficient to demonstrate this capability.

The tendon lift off forces are evaluated to ensure that 1) the rate of tendon force loss is within predicted limits, and 2) a minimum required prestress level exists in the containment.

In vrder to assess the rate of force loss, the lift off force for a tendon force is compared with the force predicted for the tendon. This predicted force includes a tolerance on force losses which are: +20% for concrete shrinkage, +25% for concrete creep, and +15% for stress relaxation. The resulting force is referred to as the Lower Limit force.

In order for the tendon lif t off force to be indicative of the level of pre-stress force in the containment, each measured force must be adjusted for the known differences which exist among the tendons due to original stressing force and elastic shortening loss.

This adjustment is accomplished through the use of a Normalizing Factor (NF (t)).

This factor is added to the lift off force, which results in the f

Normalized Lift Off Force. The Normalizing Factor is given by:

NF (t) = [F,y,(o) - F (o) ) [1 SR t)),37 (N - 2 3

+

N

[Fave( } ~ 1( )] is the group average lock-off force at original stressing, minus the original stressing force for the specific tendon.

SR(.t) is stress relaxation (percent) which occurs at time t after original stressing.

AF, is the total elastic shortening tendon force loss.

n is the stressing sequence comprising the specific tendon.

N is the total number of stressing sequences for the group,of tendons which comprise the suecific tendons.

i refers to the specific tendon.

t refers to che time after original stressing of the current inspec' ion period.

The surveillance requirements for demonstrating the containment's structural integrity are in compliance with the recommendations of Proposed Revision 3 to Regulatory Guide 1.35, " Inservice Inspection of Ungrouted Tendons in Prestressed a

CONTAIhM.in SYSTEMS

. BASES (Continued)

Concrete Containments," April 1979;'and Proposed Regulatory Guide 1.35.1, " Inservice Surveillance of Ungrouted Tendons in Prestressed Concrete Containment Structures,"

April 1979.

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ATTACHMENT I Page 16 3/82 ARTICLE IWX-3000 ACCEPTANCE STANDARDS IWX-3100 GENERAL The acceptance standards for various items (concrete, prestressing tendon components, liner deformations, etc.) of concrete cont 91nments shall be in accordance with IWX-3200, IWX-3300, IWX-3400, and IWX-?:00.

IWX-3200 PRESTRESSED CONCRETE CONTAINMENT WITH UNGROUTED TENDONS IWX-3210 TENDON FORCE ACCEPTANCE CRITERIA The containment shall be considered to have satisfied the prestressing system examination if the following tendon force (average of forces measured at both ends, if applicable) requirements are met:

a.

The average of all measured tendon forces for each type of tendon is equal to or greater than the minimum required prestress level at the anchorage for that type.

b.

The force measured in any individual tendon is equal to or greater than 95% of its predicted prestress force at the time of the test.

c.

The tendon force measured in any individual tendon divided by the total area of the effective prestressing elements which comprise the tendon, as defined in the Construction Specifications, shall not exceed 70% of the minimum specified ultimate strength of the prestressing elements.

In calculating the average force in part (a), each measured tendon force shall be corrected for initial installation conditions (actual anchorage force and clastic shortening loss during initial post-tensioning, and any other signi-l ficant effects) so that the measured force is indicative of the average level of prestress.

l The predicted prestress force at the time of the test in (b) may be determined by the method recommended in USNRC Regulatory Guide 1.35.1 or by an equivalent method.

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ATTACHMENT I Page 17

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.. 3/82 If the criterion of part (a) is not met, an investigation of the tendon system and structural integrity of the containment shall be conducted. The investigation shall include consideration of the design margins available in the containment design.

If the measured force in an individual tendon does not meet the criteria of part (b), but is equal to or greater than 90% of its predicted force, the force in adjacent tendons on each side of the individual tendon shall be measured.

If the forces in these two tendons are equal to or greater than 95% of their respective predicted forces, the inspection program shall proceed considering the event unique and acceptable. The measured forces in adjacent tendons shall be included in the calculation of the average tendon force of part (a) of this section.

If the measured force in either of the adjacent tendons or in more than one of the original sample tendons is less than 95% of its predicted force, but is not less than 90% of its predicted force, the deficient adjacent tendon (a) and the inspection tendcn shall be evaluated.

If the reason for the deficiency cannot be determined, these tendons shall have their forces measured as additional tendons in the next scheduled inspection period in order to determine if the rate of force loss is significantly greater than predicted.

If the measured force in any tendon is less than 90% of its predicted force, the tendon shall be completely detensioned and a determination shall be made as to the cause of such an occurrence and corrective action shall be taken.

In addition, all such tendons shall have their forces measured as additional tendons in the next scheduled inspection period.

ML20052F477

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