228 RAILROAD LOCATION 



as shown in the final grade line, is .03 ft. per degree. The 

 location notes for this line are as follows: 



The elevation of the grade at Sta. 27 is fixed at 120 ft., and 

 at Sta. 52, at 152.5 ft., giving between these stations an actual 

 rise of 32.5 ft. and an uncompensated grade of 1.3 %. These 

 grade points are marked on the profile with small circles. The 

 total curvature between Sta. 27 and Sta. 52 is 108$. The 

 resistance due to each degree of curvature being taken as 

 equivalent to an increase of .03 ft. in grade, the total resistance 

 due to 108,5 is equivalent to .03X108.5 = 3.255 ft. additional 

 rise between Sta. 27 and Sta. 52. Hence, the total theoretical 

 grade between these stations is the sum of 32.5 ft., the actual 

 rise, and 3.255 ft. due to curvature, or 35.755 ft. Dividing 

 35.755 by 25, the number of stations in the given distance, 

 there results 35.755 -i- 25= +1.4302 ft., as the grade for tangents 

 on this line. The starting point of this grade is at Sta. 27. The 

 P. C. of the first curve is at Sta. 29, giving a tangent of 200 ft. 

 = 2 Sta. As the grade for tangents is +1.4302 ft. per sta., 

 the rise in grade between Sta. 27 and Sta. 29 is 1.4302X2 

 = 2.8604 ft. The elevation of grade at Sta. 27 is 120 ft., 

 and the elevation of grade at Sta. 29 is 120+2.8604 = 122.8604 

 ft., which is recorded on the profile as shown in the diagram, 

 with the rate of grade, namely, +1.4302, written above the 

 grade line. The first curve is 8, and, as the compensation 



