SEWERS AND CONDUITS. 



Reinf orced-concrete sewers and conduits were developed early in the history of reinforcement. 

 The resistance to corrosion of this material in damp and wet soil and its susceptibility to special 

 design over uncertain ground and through varying depths of fill, alike drew the attention of en- 

 gineers to its possibilities. With the installment of the first reinforced concrete sewer, "Steel- 

 crete" expanded metal mesh entered this field of usefulness and the long list of notable sewers, 

 conduits, culverts and like structures in which this material has been used bears indisputable 

 evidence to the adaptibility of this reinforcement to this type of structure. "Steelcrete" mesh 

 possesses the happy combination of the two essential requirements: (1) that of being theoretically 

 correct, (2) that of being essentially practical. We submit twelve reasons why "Steelcrete" 

 mesh is superior for this particular type of structure to all other fabricated meshes or systems of 

 reinforcement. Six of these reasons are theoretical considerations and six practical ones. 



WHY "STEELCRETE" IS SUPERIOR. 



(1) It possesses a high elastic limit not less than 55,000 Ibs. per sq. in. This is not attained Theoretical 



at the sacrifice of quality or uniformity. "Steelcrete" is not a brittle and inferior steel but a Considerations 



tough, cold-drawn product with no equal in the market for uniformity of strength. The 



stresses encountered in sewer and pipe construction are uncertain and may exceed the calculated 



ones in apparently normal conditions. The need of a uniform, tough and reliable steel is at once 



apparent. 



(2) It provides against concentrated loads. Its diamond-shaped structure enables it to distri- 

 bute the effect of a sudden local load over a great many strands. No better, nor more ingenious 

 method could be devised for this important function. With straight-line reinforcement only three 

 or four strands are available, and sudden or concentrated loads are exceedingly injurious in such 

 cases. 



(3) Attains a perfect bond in the concrete. This is due to its mesh shape which does not per- 

 mit any slipping and there is no possibility of it. The concrete and steel remain intact. No 

 peeling or scaling of the concrete when subjected to heavy load. 



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