Light Weight Concrete

Progress, Volume XV, Issue 3, 1 November 1919, Page 644

Light Weight Concrete

Considerable interest has been created among engineers in Britain in a light-weight concrete employed in the construction of reinforced concrete vessels of large tonnage building in America for the United States Government. This concrete was adopted for this form of construction after an extensive series of tests on concretes of all kinds carried out by the United States Shipping Board. The tests proved that a concrete eminently suitable for use in reinforced concrete structures, and having a much lower specific gravity than that of ordinary concrete, can be obtained, by introducing an artificial aggregate having a specific gravity less than unity. It is well known that the strength of concrete depends primarily on the' strength of the binding material, and on its adhesion to the larger aggregate. This adhesion is greater to a marked degree with*the light aggregate under discussion owing to its greater surface area. To produce this increased adhesion a larger proportion of cement must necessarily be introduced, resulting in what is commonly known as a rich mixture, and, consequently, a more costly material. However, says the British journal, Engineering, its adoption in certain reinforced concrete structures must undoubtedly prove economical. Large span -reinforced concrete bridges and similar works are at present severely handicapped owing to the weight of the concrete employed in their construction, and it is in cases of this nature that the light aggregate will serve to overcome this difficulty to a large degree.

Dad s View. The, Pastor— So God has sent you two more little brothers, Dolly Dolly (brightly) Yes, and He knows where the money’s coming from. I heard daddy say so.” Tit

• Labour Trouble.— His Better - Hale (regarding him from the bedroom window)— “ Where you bin this hour of the night ?” (1 I’ve bin at me union, considerin’ this ’ere strike.” Well, you can stay down there an’ consider this ’ere lockout.”— Tit-Bits.