"A beneficial action appears to be set up in the slab, due to the tendency of the meshes to 

 close up under bending. It can be easily seen if the meshes close up by a lengthening of the 

 longer, and a shortening of the short diagonal, the area within the mesh must become reduced, 

 and consequently the enclosed concrete will be compressed. This is a very valuable property, 

 since, if the sheets are so placed that the greatest tensile stresses act in the direction of the 

 longest diagonal, it causes the concrete in the lower portion to be under compression, instead of 

 tensile stresses, as is the case with most methods of reinforcement. The sheets are made in 

 many different strengths, so that almost any size of piece can be economically reinforced. Where 

 one sheet is not of sufficient length or width, a slight overlapping of the sheets in the concrete 

 gives the necessary continuity, since its form renders any slipping through the mass of concrete 

 practically impossible." 



Also on page 296 of the same treatise : 



"There is more stretching of 'expanded metal* previous to rupture than of an ordinary rod 

 ,r wire reinforcement. Reinforcements in the nature of a woven mesh probably behave in a 

 somewhat similar manner to 'expanded metal,' but not so pronounced. 



M 



"The values of the unit moment of resistance, bh 2 , are higher for a similar percentage of 

 metal in slabs reinforced with 'expanded metal' than in those with longitudinal and transverse 

 rods." 



THE CONTINUOUS BOND IN FLAT ARCH CONSTRUCTION. 



Some reinforcements in the market, manufactured and sold in rolls, lay so much stress on the 

 continuity of their material that it may be implied that this is its chief claim to superiority. We 

 have already seen that the quality of such material is uncertain, hence unreliable. We are now 

 prepared to show that the theory of the much-heralded continuous bond is exaggerated to a 

 very small extent exists in practice and this can be clearly demonstrated. 



13 



