ML102920064
| ML102920064 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 09/20/2010 |
| From: | Erlin B Erlin, Hime Associates |
| To: | Office of Information Services |
| References | |
| FOIA/PA-2010-0116 | |
| Download: ML102920064 (5) | |
Text
- .* , ATTACHME'.NT , "C" Q.2 ERLIN, HIME ASSOCIATES MATERIALS AND CONCRETE CONSULTANTS Su-* KItE DOULEVARO (312) 272.7730
.,*$,t~ l~C'x. ILLINOIS 60062 PETROGRAPHIC STUIES OF CONCRETE FOR CONSTRUCTION ENGINEERING CONSULTANTS
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SUMMARY
AND DISCUSSION
- The specimen represented air-entrained concrete.
made with. crushed fossiliferous coarse aggre-gate and siliceous fine aggregate and a low water-cement ratio paste. There was no evidence that the aggregates had been 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.
INTRODUCTION Reported R herein are the results of petrographic studies of a concrete fragment submitted by J. Artuso of Con-struction 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.
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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 partichlarly 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 specirhen was medium dark grey' firm, and contained abundant residual and relict cement. The quality of the paste reflects a low wate+/--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 5- 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 aciculariettringit'i (3CaO-A1203"3CaSO4 '31H 2 0), and calcite ( 6 aCQ 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
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ERLIN. HIME ASSOCIATES - MATERIALS AND CONCRETE CONSULTANTS oriented subparallel to the long axis. of the fragment.
The fractures transected coarse aggregate particles. On those fracture s-urfaces were secondary deposits similar to those described above.
I The secondary compounds demonstrate that the fragment was from an area where fractures present for a period of time had been exposed to moisture.
.May 10, 1976 Erlin, Hime Associates, Inc.
by Bernard Erlin, President Petrographer c-14
DIRECT TENSILE STRENGTH TEST RESULTS NOMINAL TOTAL AREA DIAMETER LOAD CORE SO. IN IN. LBS. P.S.I. REMARKS Granite aggregate .8.19 3 1/4 3400 415 concrete 5000 p.s.i. value 8.14 3 1/4 3200 390 Crystal River Cores Average 400 p.s.i.
N Pour XVI -10.69 3 3/4 2500 230 All Coarse
____ ..... aggregate soft MPour XVIII 10.69 3 3/4 4600 430 Hard Coarse aggregate except.
two soft pieces L Pour XV 10.69 3 3/4 5400 505 All hard coarse Ln aggregate L Pour 9B 10.69 3 3/4 5400 485 Most coarse aggregate hard P Pour XIII 10.69 3 3/4 5400 505 All hard coarse
___aggregate Pour XII .:10.63 3 3/4 3800 3 All small soft
,.,-_coarse aggregate' Average 420 p.s.i.
6ote: The Granite Aggregate concrete cores fractured surfaces indicated all coarse aggregate was hard and dense and several pieces of the CA pulled out of the Matrix, indicating rt ft greater tensile strength than the Matrix. There was no pull out of the Crystal River coarse aggregate - all fractured at the fractured surface.
0 ft
ATTACHMENT E Preliminary Report of Crystal River Coarse Aggregate ASTM Spec Sieve Wgt. Ret. % Passing # 67 1 0 100 100 3/4 1.0 97 90-100 1/2 15.8 58 3/8 28.4 24 20-55 4 35.8 4 0-10 8 36.3 3 0-5 Pan 37.3 Test Result ASTM Specification C-117 200 Wash Loss 1.3%(Primarily 1% Max*
dust of fracture)
C-131 Los Angeles Abrasion 42 % 50% Max C-123 Lightweight Pieces in Aggregate 0.2% 0.5% Max C-29 Unit Weight of Aggregate 85.68 lbs/cu. ft. No Spec C-142 Friable Particles Later 5.0% Max C-235 Soft Particles Later 5.0% Max C-88 Soundness (Sodium Sulphate) Later 12.0% Max C-127 Specific Gravity and Absorption Later No Spec
- This limit may be increased to 1.5% if the material finer than a No. 200 consists essential of dust from fracture 0C-16