REINFORCED 

 CONCRETE CONSTRUCTION 



PART I 



PROPERTIES OF THE MATERIAL 



Reinforced Concrete is concrete which is strengthened by 

 having embedded in it some metal, usually steel. 



The component materials should separately possess certain 

 properties, if satisfactory strength and durability are to be 

 obtained in the structures having these materials in combination. 

 The properties of each material will now be discussed, and those 

 properties in particular will be emphasized which have the most 

 to do with the safe and economic designing of structures. 



CHAPTER I 

 CONCRETE 



1. General Requirements. Concrete used in reinforced con- 

 crete construction should be strong, of uniform quality, free 

 from voids, and thoroughly sound. These qualities are required 

 even more than in massive concrete, as the sections in reinforced 

 concrete structures are comparatively small and the stability of 

 a given structure depends upon the strength and durability of 

 every part. 



The proportions commonly used in American practice vary 

 from about 1:1 1/2:3 to 1:3:6, using either crushed stone or 

 gravel. The rich mixture is usually required in structural 

 parts subjected to high stresses or where exceptional water- 

 tightness is desired. On the other hand, the use of a 1:3:6 

 concrete requires careful grading of the materials to produce 

 satisfactory results, even for ordinary work. 



