TIMBKR PHYSICS — METHODS. 



395 



CKOSS BREAKING TEST. 



Longleaf pine. 



fS. 

 Mark, 3. 



|l. 



Length, 60.0 inches. 

 Height, 3.50 inches. 

 Jireadth, 3.72 inches. 



[Number annual rings per inch =23.] 



60QO [ 



Strength of extreme fiber, 



3 IF 7 

 where f=efyry= 10,230 pounds per square inch. 



Modulus of elasticity =1,760,000 pounds per square inch. 

 Total resilience =5,110 inch-pounds. El. Res., 1,780. 



Resilience, per cubic inch =6.54 inch-pounds. El. Res., 2.28. 



July | 

 20,1891. Load. 



i 



h. m. ' 



2 58 200 



3 . 1,000 



1 ' 1,600 



2 , 2,000 



3 ' 2,400 



4 2, 800 



5 3, 200 



6 3, 600 



7 4, 000 



8 4, 400 



9 4, 800 

 13 i 5,180 



Deflec- 



Micro - 



tion. 



meter. 



042 



0.958 



.208 



1.124 



.324 



1.240 



.404 



1.320 



.481 



1. 397 



.558 



1.474 



.640 



1. 556 



.721 



1.637 



.815 



1.731 



.926 



1.842 



1.074 



1.990 



1.544 



2.460 



Remarks. 



Maximum load 



D e flection in incites. 

 FINAL RECORD OF TIMBER TESTS. 



Mark. 



Longloaf pine; 



3 



3 



1 



"White pine : 



116 



1 



3 



Percent- 

 age of 



moisture 



16.8 



54.3 



Cross bending test. 



Dimensions. 



Length. 



Inches. 

 60.0 



60.0 



Height. 



Inches. 

 3.50 



3.74 



"Breadth. 



Inches. 

 3.72 



3.75 



Time. 



Min. 

 15 



16 



Load. 



Pounds. 

 5,180 



3,300 



Deflec- 

 tion. 



Inches. 



1,544 



1,521 



Strength 



per 



square 



inch, (f) 



Pounds. 

 10, 230 



5,660 



Modulus 

 of elas- 

 ticity, (e) 



Pounds. 

 1, 760, 000 



1, 320, 000 



Resilience 

 in inch- 

 pounds per 

 cubic 

 inch, (r) 



6.54 



4.11 



Maik. 



Longleaf pine : 



3 



3 



"White pine . 



116 



1 



3 



Crushing endwise. 



Dimensions. 



Height. 



Inches. 

 8.1 



7.6 



Cross 

 section. 



Inches. 



3.46 



3.72 



3.73 

 3.73 



Area. 



Sq. in. 

 12.87 



13.91 



Crushing 

 load. 



Pounds. 

 77, 700 



48, 400 



Strength 



per 



square 



inch. 



Pounds. 

 6,040 



3,480 



Crushing across grain. 



Dimensions. 



Height. 



Inches. 

 3.73 



3.72 



Cross 

 section. 



Inches. 



3.47 

 3.93 



3.72 

 3.93 



Area. 



Sq. inch. 

 } 13.63 



\ 14.62 



Crushing 

 load. 



Pounds. 

 10, 400 



5,200 



Strength 



per square 



inch. 



Pounds. 

 760 



360 



Mark. 



Longleaf pine: 



3 



3 



1 



White pine: 



116 



1 



3 , 



Tension tests. 



Size of re- 

 duced sec- 

 tion. 



Sq.inch. 



2.38 

 .41 



2.52 

 .45 



Area. 



Sq. inch. 

 \ 0. 976 



\ 1. 134 



Breaking 

 load. 



Pounds. 



11,400 



11, 200 



Strength 



per square 



inch. 



Pounds. 

 11, 680 



9,880 



Shearing tests. 



Total 



shearing 



area. 



Sq. inch. 



4.14 

 3.97 



4.16 

 4.02 



Breaking 

 load. 



Pounds. 



2,280 

 2,580 



1,700 

 1,600 



Shearing 

 strength. 



Pounds. 



551 



650 



409 

 398 



■■'"■■' — fWHHMB 



