1. SOIL MECHANICS

2. Soil Mechanics (EEG 312)Laboratory WorksCONSOLIDATION TEST ( ) 3. : ... :saturated clayGL ( ) : . . 4. : ... ( 24 ) Coefficient of Consolidation . . 5. :Consolidometer Sample mold Loading Arm . 6. : ... One Dimensional , 40 - , 20 45 113 . . 7. : , . . 8. : :1) Coefficient of consolidation (Cv)2) Compression index (Cc). : Elastic or Immediate Settlement (Se). . Primary consolidation settlement (Sc). . Secondary consolidation settlement (Sp). . :ST = Se + Sc + Sp . 9. ...Consolidation of Soil . 10. : . 11. : : . 12. 40-20 45 113 . porous stones pour water pressure . 200( ) 200 0.002 . x 1 consolidometer . . 13. . , . . , . . 14. : :- :1. .2. .- , :1. .2. ( ).3. .4. .5. .6. . . 15. - : : : "" 20 40 45 113 1 2.5D/H = 1 - 2.5 mm , , () . (Wet Clay) (Saturated Clay) : . 16. - : : : ( ) , . Dial Gauge 4 12 . . 17. : :- : , : 200 ( 100 , 200 ). 0.002 . . 18. - : , :Kg/cm Kpa (Kn/m)1/4 251/2 501 1002 2004 4008 80016 160032 32000 : :43 Kg/cm = Kpa (Kn/m)67 Kg/m = Kpa (Kn/m)350 gm/cm = Kpa (Kn/m) : : . 19. - : :Rate of loadingKg/cm1/4 =0.251/2 = 0.5012481632 : :Stress Kg/cm Weight (kg)0,254 5000.509 11.019 22.03 44.07 88.1 1616.3 3232.6 64 . 20. : :- : () . 1 x ( = 1 10 / ( 40 25 . / = 40 / 10 = , . : . . 21. - : : : ( 500 ) , , . . 22. : : . . 23. :- : , Settlement (S) : . :Coefficient of Consolidation (Cv) :Coefficient of Axial Compressibility (av) :Coefficient of Volume Change (mv) : Compression Index (Cc) : Swelling Index (Cs) : Recompression Index (Cr) : Preconsolidation Pressure (Pc) : Compression Ratio (Cc') : Over Consolidation Ratio (O.C.R) : Coefficient of Permeability (K) 24. . :Coefficient of Consolidation (Cv) () () :Square root of time method Logarithm of time method Hyperbola method 132 25. :Coefficient of Consolidation (Cv) ( ) ( ) : . T50 T900.197 (H)T500.848 (H)T90 26. Logarithm of time method )()(%50, ) )Cv = . ( ) . 27. Square root of time method ( )( )%90, ) )=0.848 (H)T90 . 28. T50 T900.197 (H)T500.848 (H)T90 . 29. Hyperbola method )) ((, md) )= 0.3 () . 30. : ) : )T - 50 :1. .2. . , . ( ) : . 1. . . 2. . 31. : ( 250 Gm ) mm mm (0.002)mm time (min)0.25 106 0.2120.5 121 0.2421 142 0.2842 174 0.3484 214 0.4288 276 0.55215 359 0.71830 483 0.96660 564 1.128120 636 1.272240 673 1.3461440 710 1.42 . 32. , , :D , = 0D ( ) 100 % = 100D ( ) 50 % = 50T100 =% 100T 50 % ( ) = 50 . 33. Consolidation Test , Load (250 gm)D 0 :T50 T100 , , ( ) D0D50D10000.10.20.30.40.50.60.70.80.911.11.21.31.41.50.01 0.1 1 10 100 1000 10000T1 = 4*T1 : 0.5 4 ( ) 2 . 34. :D100 1.27 mmT100 135 minD0 0.15 mmD50 0.71 mmT50 17 min . 35. :- : , : . =Ws . . = Gs . = D . = r.(r) , =A 1 . = w , . = Hs . = H . = H , . = Vi . = e= = = 36. :- : , : . 37. :- : , : . 38. . . :- : 39. Coefficient of Axial Compressibility (av) : , ( ) : . =m/Kn 40. Coefficient of Axial Compressibility (av) )) (( , yx . 41. Coefficient of Volume Change (mv) , : . =1 + e m/KnSoil Type mv (m/Kn )Very Highly Compressible > 0.001Highly Compressible 0.001 0.0002Med. Compressible 0.0002 0.00005Low Compressible 0.00005 0.00002Very Low Compressible < 0.00002 42. . : Compression Index (Cc) ( )( ) ( ) ( ) :Cc =log / 43. . : Swelling Index (Cs) Cs =log / ( )( ) ( ) ( ) : 44. . : Recompression Index (Cr) Cr =log / ( ) ( ) () ( ) : 45. . Cc =log / (Unloading)(Reloading) :Compression Index Cc 46. . : Reconsolidation Pressure (Pc) ( ) ( ) ( ) ( ) : . (a) 1) .(a) (b) 2) .(a) (c) 3) (d) 4) .(b) (c) . (e) 5) (g) 6) .(d) (h) (f) acbdge 47. Strain . : Compression Ratio (Cc') Cc = log / () ( ) ( )( ) : 48. : Over Consolidation Ratio (O.C.R) : . O.C.R =PcP :Pc = = 49. O.C.R = 1O.C.R > 1 Preconsolidated Clay ( Pc > P' ) . . : O.C.R Normally consolidated Clay ( Pc = P' ) .O.C.R < 1 Under consolidated Clay ( Pc < P' ) . (Pc) 50. . : Coefficient of Permeability (K) : :mv = Cv = =K = mv Cv m/min 51. . : Coefficient of Permeability (K) , : 52. . Settlement (S) , , :S = [log log ] : = = = ( + )= = ( ( *Cc = 53. . Settlement (S) : 54. : ... . 55. . 56. . 57. . 58. . 59. . ( ( u ( ( ' ( ( ' = u + 60. .