ML102871046

5.5 Exhibit 3a Petrographic Erlin Hime May 19

ML102871046
Person / Time
Site:	Crystal River
Issue date:	01/01/2010
From:	Erlin, Hime Associates
To:	Office of Information Services
References
FOIA/PA-2010-0116
Download: ML102871046 (3)

Text

F_ 5.5 Exhibit 3a2 page 1 of 3.

ATTACI IM1ENT C II ERLIN, HIME ASSOCIATES MATERIALS AND CONCRETE CONSULTANTS "hc~ll GOULIEVARID (312) 272.7730 ILLINOIS 60062

• PETROGRAPHIC STUDIES OF CONCRETE FOR CONSTRUCTION ENGINEERING CONSULTANTS

SUMMARY

AND DISCUSSION

-The specimen represented alr-entrained concrete made with, crushed fossiliferous coarse aa re-Awater-cement ratio paste. :There was no evidence that the aggregates had een either chemically or physically unsound.

The specimen was from an area where fractures had existed for a period of time and where moisture had been present. That was demon-strated by secondary deposits on fracture surfaces.

The specimen was relatively small. Larger specimens fr.om different areas of the struc-ture would be desirable for examination in order to obtain a better representation of the concrete.

"t, . . .* * *. *.*. * .,

INTRODUCTION Reported herein are the results of petrographic studies of a concrete fragment submitted by J. Artuso of Con-struc'tion Engineering Consultants. The specimen is from the dome of the containment structure of the Florida Power Corporation, Crystal River, Unit III.

• Requested by Mr. Artuso were petrographic studies for evaluating the specimen, and particularly for evidence of features that would cause volume instability.

C-12 FM 5.5 Exhibit 3a 01/01/10 page 1 of 3 1

r . I FM 5.5 Exhibit 3a page 2 of 3 ERLIN. HIME ASSOCIATES MATERIALS AND CONCRETE CONSULTANTS STUDIES-Specimen - The specimen was an elongated fragment having nominal-lateral dimensions of 5 inches, and a maximum thickness of about 3/4 inch.

All surfaces were fracture surfaces except for a shallow channel about 3/32 inch wide and 1/8 inch deep. The channel appears to be the terminal area of a saw cut.

Petrographic Studies - Coarse aggregate of the specimen was a buff to light brown, fine-grained, fossiliferous limestone having a maximum nominal size of 3/4 inch.

The fine aggregate was a siliceous sand composed prin-cipally of quartz.

The aggregates were not particUiarly well graded, as evidenced by deficiencies of the finer sizes of the coarse aggregate and the coarser sizes of the fine aggregate.

There was no evidence that the aggregates had been chemically or physically unsound. Particular attention was directed to alkali-silica reactivity with respect to the coarse aggregate because a similar type of aggregate does contain a highly reactive variety of chert. Neither the chert nor the product of the reaction of the chert with alkalies (alkali-silica gel) was present.

Paste of the specimhen was medium dark grey, firm, and contained abundant residual and relict cement. The Iquality of the paste reflects a low watei-cement ratio.

Air occurred as small, discrete, spherical voids that bccasionally were very slightly distorted, and as coarser irregularly shaped voids. The spherical voids are characteristic of entrained air voids; the irregularly

• shaped voids ,:. of entrapped air,. The air content of :the specimen is estimated to be 51 percent and the parameters of the air-void system are judged to be effective for protecting critically saturated concrete exposed to cyclic freezing.

On one of the lateral surfaces were secondary deposits composed of tufts of fine acicularletti'ngit'_(3CaO.

A1203"3CaSO4 31H2 0), and calcite ( 6 aC0 3 ). Ettringite) was also present as tufts in some air voids"just-below.

the fracture-surface.

The fragment was not uniformly thick; it tapered to a knife-like edge. Along that edge, were fine fractures C-13 FM 5.5 Exhibit 3a IIII ~~01011 I I II page 2 of 3 FM 5.5 Exhibit 3a 01/01 / 10 page 2 of 3

FM 5.5 Exhibit 3a a -

page 3 of 3 ERLIN, HIME ASSOCIATES - MATERIALS AND CONCRETE CONSUJLrANTS oriented subparallel to the long axis of the fragment.

The fractures transected coarse aggregate those fracture s-urfaces were secondary particles. On to those described above. deposits similar The secondary compounds demonstrate was from an area where fractures that the fragment present for a period of time had been exposed to moisture.

May 10, 1976 Erlin, Hime Associates, Inc.

by Bernard Erlin, President Petrographer I'F,

.6 ",

C-14 FM 5.5 Exhibit 3a Fh/01/1oa page 3 of 3