Superior 

 Quality of 

 "Steelcrete" 



Value of 

 Ductility 



An Impartial 

 Opinion 



To summarize, the high elastic limit, while undoubtedly desirable, must not be attained at the 

 sacrifice of quality. It should not be overlooked that "the quality remains long after the price 

 is forgotten." "Steelcrete" Expanded Metal stands for superior quality; a uniform product with 

 a high elastic limit. 



The second distinctive feature of "Steelcrete" Expanded Metal which is intimately connect- 

 ed with the subject of the high elastic limit is ductility. 



The property of high elastic limit is generally accompanied with a great decrease in the duc- 

 tility of the material. The effect of this on the safety of a building should not be overlooked. It 

 is never possible to calculate all of the loads that a building will be required to sustain. The 

 falling of a two-ton load on a floor from the height of one foot will produce stresses on the 

 whole building that will far exceed the common calculated quiescent loads. A shock due to 

 internal or external explosions, earthquake shocks, common shocks encountered in the erection 

 of the structure; none of these can be calculated. Conservative engineers provide for them by 

 selecting a material which possesses ductility; in other words, which will yield under shock rather 

 than snap in two, such as would be the case with a material possessing a low ductility. Such 

 materials should be absolutely prohibited on beams and girders, as upon them depends the safety 

 of the building. Elsewhere we have spoken of the tendency of the diamond meshes in an Ex- 

 panded Metal sheet to close under severe loading. This will be readily granted by an observer. 

 The effect of this feature on Expanded Metal embedded in concrete is obviously to give the re- 

 inforcement a ductility unencountered in any other fabric possessing a high elastic limit. As this 

 closing cannot take place except under a severe loading or shock, the advantages of a high 

 elastic limit as well as that of a ductile metal are attained. 



This feature of Expanded Metal, namely, the tendency of the diamond meshes to close, has 

 the effect of introducing a compression into the concrete which is under tension at this point. 

 The immediate effect is to lower the neutral axis in the slab, which increases the effective area 

 of concrete available for the resistance of compressive stresses and decreases the stresses in the 

 extreme fibres. The beneficial effect cannot be denied. It has been recognized by concrete ex- 

 perts the world over. The following extracts describe it better than we could ourselves. 

 They are taken from the 600-page exhaustive treatise on Reinforced Concrete by Charles F. 

 Marsh, page 54: 



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