Memorandum from Raymond L. Murray to Dr. C. K. Beck
Typescript
2 pp.
June 14, 1951
MurNBcolemanite061451



June 14, 1951

Dr. C. K. Beck
cc: A. C. Menius
File

In accordance with your request, I checked with Dr. Kitzes of
ORNL and his assistant, Mr. Gallaher, on the Coleminite concrete.
Their remarks and recommendations are reproduced below.

1. The basic problem in the setting of this concrete is that
the boron compound dissolves in water, resulting in a solution that
inhibits the action of Portland cement. The amount of water added
must be carefully controlled, and the mix prepared in a much dryer
state than is conventional in concrete practices, and in fact, giving
such a constituency that contractors are very much alarmed. The
added water should be as cold as possible because of the solubility
problem.

2. The exact proportions at the various constituents have been
established by experiment; once they are found and the procedure for
preparation followed religiously, a reproducible satisfactory concrete
is obtained. (To my untrained eyes the test blocks I was shown looked
very good.)

3. The two mixes that have been used successfully were:


[ [2]]

TABLE
Wt. (lb)%
3/4" ASTM (Coarse)349064.2
3/8" (Fine)2103.9
Coleminite (dust)4006.4
Type III Cement (Hierly)4608.5
Lumnite4608.5
Water< 55 gal8.5 (2" slump)
5430100.0

RM
Raymond L. Murray
RLM:ab