Uniform Stress and Permanent Strain. 



9 



Test of one specimen cut from a bar of wrought-iron. Brand 

 R.H. Crown B.B.B. Duration of stress jo minutes. 



No. of 

 Specm. 



Initial 



Area, 

 sq. in. 



Final 

 Area, 

 sq. in. 



Permanent 

 Strain. 



Stress on 



Reduced Section. 



Tons. 



Value 

 ofC. 



7- 



7776 



•7646 



•OI73I 



I4-5 8 3 



40'20 







— 



7594 



•O2462 



• 16*000 



40-39 











IS 2 ! 



•O3526 



17-472 



40-31 



z 







7447 

 7306 



•04914 

 •06822 



i9'ooo 

 20735 



4C36 

 40-57 



— 







•7103 



•IOO96 



22740 



40^4 



Test of one specimen cut from a bar of mild steel. Duration 



No. of 

 Specm. 



6. 



Initial 

 Area, 

 sq. in. 



7689 

 7515 

 7458 

 7390 

 7302 

 7200 

 7050 

 •6793 



of stress 30 minutes. 



Final Permanent Stress on 



Area. Set. Reduced Section, 



sq. in. Tons. 



•O2233 

 ^3015 

 •04OO3 

 •O5168 

 •06752 

 •O9OO5 

 •I3I40 



19-294 



20780 

 22-330 

 23-970 

 25-694 

 27*660 

 30-178 



Value 

 ofC. 



49-92 

 49-88 

 49-92 



50-27 



5°'4i 

 5° "49 

 5 0<I 3 



Table II. 



Tests of nine specimens cut from a bar of wrought-iron. Brand 



R.H. Crown B.B. 







Value of k= "265. 







No. of 



Initial 



Final 



Permanent 



Stress on 



Value 



Specm. 



Area. 



Area. 



Strain. 



Reduced Section. 



ofC. 





sq. in. 



sq. in. 





Tons. 





R. 5. 



7651 



7475 



•O249 



14792 



39'358 



R. 2. 



7658 



7412 



•0385 



16-554 



39-242 



R. 7. 



7667 



7344 



•0475 



I7-430 



39-090 



R 3- 



7635 



7185 



•o66l 



19*207 



39'455 



R. 6. 



7651 



7151 



•O756 



20'025 



39700 



R. 8. 



7627 



•6991 



•O99I 



2I'I70 



39-063 



R. 4. 



7658 



•6940 



•II29 



21*990 



39-200 



