ML12200A243

Email from M. Galloway, NRR to A. Sheikh, NRR Et Al., Davis-Besse Shield Building

ML12200A243
Person / Time
Site:	Davis Besse
Issue date:	12/13/2011
From:	Galloway M Division of License Renewal
To:	Erickson A, Bryce Lehman, Sheikh A Division of License Renewal
References
FOIA/PA-2012-0121
Download: ML12200A243 (1)

Text

Erickson, Alice q1(

From: Galloway, Melanie Sent: Tuesday, December 13, 2011 8:39 AM To: Sheikh, Abdul; Lehman, Bryce; Erickson, Alice Cc: Manoly, Kamal; Hiser, Allen; Delligatti, Mark; Auluck, Rajender; Sakai, Stacie

Subject:

RE: Davis Bessee Shield Building Thanks much, Abdul.

This will be useful information as part of the comparison presentation on the 22 nd From: Sheikh, Abdul Sent: Thursday, December 08, 2011 8:09 AM To: Lehman, Bryce; Erickson, Alice Cc: Manoly, Kamal; Galloway, Melanie; Hiser, Allen; Delligatti, Mark; Auluck, Rajender; Sakai, Stacie

Subject:

Davis Bessee Shield Building During the briefing on December 6, 2011, there was a question about the similarity between Crystal River and Davis Bessee laminar cracking. The facts are:

Davis Bessee shield building laminar crack widths are between 0.005 to 0.01 inch (5-10 mils)

Crystal River containment laminar crack widths were between 0.5 to 4 inch (500 mil to 4000 mils)

Ratio of crack widths between two structures: 50 to 400 Crystal River cracking occurred 8-9 inches from the outside face of concrete Crystal River cracking is due to prestressing forces, lack of transverse shear reinforcement, and weak aggregate Davis Bessee shield building cracking is about 2-3 inches from outside face concrete Davis Bessee shield building is not prestressed Davis Bessee shield building has not been designed for containment accident pressure and temperature.

Davis Bessee has a steel containment All the above information indicates that laminar cracking at both structures are not similar.

Abdul