flakiness and elongation index

     


 The elongation index of aggregate the percentage by weight particles  who's greatest dimension length is greater then 1.8 times there means dimension. 

The flakiness index of the aggregate percentage by weight of particle whose dimension (thickness) is 0.6 times there men dimension 

         Sieve size(mm)

Weight of aggregate taken in gram

   (A)

Weight of aggregate retained on thickness gauge in gram

               (B)

Weight of aggregate passing on thickness

gauge in gram

             (C)

Weight of aggregate retained on length gauge in gram

           (D)

Passing

    Retained

25mm

20mm

348

324

24

32

20mm

16mm

870

781

89

15

16mm

12.5mm

767

672

95

255

12.5mm

10mm

325

221

104

62

10mm

6.3mm

157

89

68

41

Total weight in gram

2467

2087

380

405

 

 

Flakiness index= (C/A) *100                             = (380/2467) X 100                       =15.4

 

 

Elongation index= (D/A) *100                         = (405/2467) X 100                       =16.42

 

 

Combined Flakiness & Elongation%               = (15.4+16.42)                               =31.82


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