Self-Test C-1.7.2: Calculate Piping Measurements

Complete Self-Test C-1.7.2 and check your answers.

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = [latex]\frac{1}{8}\text{"}[/latex] per foot

Length = 95 feet

Total fall =                                                     in.

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = 1%

Length = 125 feet

Total fall =                                                     in.

  1. Calculate the pipe length:

Total fall = 0.95 feet

Grade = 2%

Length =                                                     ft.                                                     in.

  1. Calculate the pipe length:

Total fall = 11 inches

Grade = [latex]\frac{1}{8}\text{"}[/latex] per foot

Length =                                                     ft.

  1. Calculate the grade in inches per foot:

Total fall = 24 inches

Length = 192 feet

Grade =                                                     [latex]\frac{\text{in.}}{\text{ft.}}[/latex]

  1. Calculate the grade as a percentage:

Total fall = 4.5 feet

Length = 475 feet

Grade =                                                     %

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = [latex]\frac{1}{8}\text{"}[/latex] per foot

Length = 130 feet

Total fall =                                                     in.

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = 0.5%

Length = 445 feet

Total fall =                                                     in.

  1. Calculate the length:

Total fall = 162 mm

Grade = 1%

Length =                                                     m

  1. Calculate the length:

Total fall = 18 inches

Grade = 1:133

Length =                                                     ft.

  1. Calculate the grade in inches per foot:

Total fall = 8 inches

Length = 128 feet

Grade =                                                     [latex]\frac{\text{in.}}{\text{ft.}}[/latex]

  1. Calculate the grade as a percentage:

Total fall = 3 feet

Length = 555 feet

Grade =                                                     %

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = [latex]\frac{1}{4}\text{"}[/latex] per foot

Length = 19 feet

Total fall =                                                     in.

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = 1:50

Length = 95 feet

Total fall =                                                     in.

  1. Calculate the pipe length:

Total fall = 18″

Grade = 1.5%

Length =                                                     ft.

  1. Calculate the pipe length:

Total fall = [latex]8\frac{7}{8}\text{"}[/latex]

Grade = 1:50

Length =                                                     ft.                                                     in.

  1. Calculate the grade in inches per foot:

Total fall = 23″

Length = 184′

Grade =                                                     [latex]\frac{\text{in.}}{\text{ft.}}[/latex]

  1. Calculate the grade as a percentage:

Total fall = [latex]54\frac{3}{4}\text{"}[/latex]

Length = 456′

Grade =                                                     %

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = [latex]\frac{1}{16}\text{"}[/latex] per foot

Length = 165′

Total fall =                                                     in.

  1. Calculate the total fall to the nearest [latex]\frac{1}{8}[/latex] inch:

Grade = 1.5%

Length = 325 feet

Total fall =                                                     in.

  1. Calculate the length:

Total fall = 18″

Grade = 1.04%

Length =                                                     ft.

  1. Calculate the length:

Total fall = 45″

Grade = [latex]\frac{1}{8}\text{"}[/latex] per foot

Length =                                                     ft.

  1. Calculate the grade as a ratio:

Total fall = 9″

Length = 37′ 6″

Grade =                                                    

  1. Calculate the grade as a ratio:

Total fall = 4.66′

Length = 1400′

Grade =                                                    

  1. Convert each measurement to engineer’s measurement (3 decimal places):

a. 18′ 6″ =                               d. 33′ 10″ =                    

b. 15′ 5″ =                               e. 35′ 11[latex]\frac{1}{4}[/latex]” =                    

c. 32′ 9″ =                   

  1. Convert each measurement to builder’s measure (nearest [latex]\frac{1}{8}\text{"}[/latex]):

a. 84.27′ =                               d. 123.44′ =                    

b. 93.08′ =                               e. 156.92′ =                    

c. 106.71′ =                    

  1. A house construction site has a benchmark of 100.00′, basement floor elevation of 94.20′, first floor elevation of 103.75′ and second floor elevation of 113.00′.
    1. How far below the benchmark is the basement floor?

Answer =                                                                                                                  

    1. How far above the benchmark is the first floor?

Answer =                                                                                                                  

    1. What is the distance from the basement floor to the first floor?

Answer =                                                                                                                  

    1. What is the distance from the first floor to the second floor?

Answer =                                                                                                                  

  1. The low end of a sanitary building drain has an elevation of 91.55 feet. The grade is [latex]\frac{1}{8}[/latex] inch per foot.
    1. What is the elevation of a fitting 10′ upstream of the low point?

Answer =                                                                                                                  

    1. What is the elevation of a fitting 25′ upstream of the low point?

Answer =                                                                                                                  

  1. Refer to Figure 27 to solve for the unknown values.
Figure 27 Illustration for problem 29

Notes:

  • Main line (pipe sections 1 & 4) are 12″ in diameter
  • Branch line (pipe sections 2, 3, 5 & 6) are 6″ in diameter
  • Grade on all pipe sections is [latex]\frac{\frac{1}{8}\text{"}}{\text{ft.}}[/latex]

Sump:

  • Liquid depth = 24″
  • Inlet is 4″ higher than outlet
  • Sump height = 60″

Catch basin:

  • Liquid depth = 18″
  • Catch basin height = 36″ Pipe lengths:
  • Main sections:

▸ Pipe section 1 = 30′

▸ Pipe section 4 = 125′

  • Branches:

▸ Pipe section 2 = 75′

▸ Pipe section 3 = 21′

▸ Pipe section 5 = 40′

▸ Pipe section 6 = 64′

The invert level of a pipe is the level taken from the bottom inside of the pipe, as shown.

 

Figure 28 Pipe invert

Solve for the following elevations in feet to 3 decimal places:

A. Outlet invert =                               D. Outlet invert =                    

B. Inlet invert =                               E. Top elevation =                    

C. Outlet invert =                               F. Top elevation =                    

 

Answer Key: Self-Test C-1.7.2 is on the other page.

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