RASCO CIVIL ENGINEERING REVIEW

ALOJA COFFEE SHOP, LIBAS, BANGA, AKLAN

CP: 09164618841 / Landline: (036) 267 - 7343

GEOTECHNICAL ENGINEERING EVALUATION 1

SET B The results of the sieve analysis of soils A, B, and C is given below. It
is required to classify these soils according to USCS.
Directions: Select the best answer.
11. Which of the following classifies Soil A?
1. Evaluate the dry unit weight of a soil mass having a void ratio of a. GP c. SP
0.50 with specific gravity of 2.5 for its solid grains, in kN/m^3. b. GW d. SW
a. 14.9 c. 16.4
b. 14.6 d. 17.3 12. Which of the following classifies Soil B?
a. SM c. GC
The coefficient of permeability below a dam is 4 m/day. The water b. SC d. GM
on the upstream side is 30 m higher than on the downstream side.
To estimate the seepage below the dam, a flow net was graphically 13. Which of the following classifies Soil C?
drawn such that the number of potential drops, Nd = 10 and the a. OL c. ML
number of flow channels Nf = 4. The base of the dam is founded 1 m b. CL d. CH
below the ground. Between the heel and the toe of the dam, a
distance of 30 m, there are 8 potential drops. Evaluate SOIL SAMPLE (percent passing)
Sieve No. Dia (mm) A B C
2. The seepage flow per meter width of the dam, in li/min 4 4.76 90 100 100
a. 18.6 c. 20.6 6 2.38 64 90 100
b. 33.33 d. 32.5 10 2.000 54 77 98
20 0.840 34 59 92
3. The uplift pressure at the heel of the dam, in kPa 40 0.420 22 51 84
a. 114 c. 198 60 0.250 17 42 79
b. 265 d. 181 100 0.149 9 35 70
200 0.074 5 33 63
4. The uplift force, in kN/m, per meter length of the dam.
a. 11.4 c. 14.7
LL - 46 47
b. 17.6 d. 4415
PL - 29 24
5. Which component of rock or soil is independent of interparticle
friction? 14. The dry unit weight of a soil sample is 10 kN/m^3. What is the
a. adhesion c. plasticity moist unit weight (kN/m^3) of the soil when its moisture content is
b. cohesion d. skin friction 15%?
a. 10.8 c. 11.5
A 5-m clay layer lies beneath an 8-m sand layer. The sand is 3 m b. 13.6 d. 12.2
below the water surface. Saturated unit weight of sand is 25 kN/m^3
and clay is 20 kN/m^3. Calculate the following: A 3-layer soil has the following properties from top to bottom:

6. The total vertical pressure (kPa) at mid-height of clay layer Layer k, cm/s Thickness, m
a. 240.1 c. 209.3 1 2 x 10^-4 4
b. 248.6 d. 279.4 2 3.2 x 10^-2 3
3 4.1 x 10^-5 6
7. The pore water pressure (kPa) at mid-height of clay layer
a. 122.6 c. 112.8 Determine
b. 132.4 d. 152.1
15. Equivalent horizontal coefficient of permeability, in cm/s
8. The effective vertical stress at mid-height of clay layer a. 0.0000709 c. 0.00809
a. 147 c. 99.4 b. 0.0000805 d. 0.00747
b. 96.5 d. 117.5
16. Equivalent vertical coefficient of permeability, in cm/s
9. According to USCS, what do you call a solid grain with grain size a. 0.0000709 c. 0.00809
greater than 4.75 mm but less than 75 mm? b. 0.0000805 d. 0.00747
a. rock c. boulder
b. gravel d. cobble 17. rate of flow in the vertical direction per sq m of layer, in li/hr, if
the hydraulic gradient is 0.50
The results of a constant head permeability test for a fine sand a. 4.65 c. 1.45
sample having a diameter of 150 mm and a length of 300 mm are as b. 3.24 d. 2.85
follows:
18. A phenomenon in which the strength and stiffness of a soil is
Constant head difference = 500 mm reduced by earthquake shaking or other rapid loading.
Time of collection of water = 5 min a. liquefaction c. erosion
Volume of water collected = 360 cc b. settlement d. solidification

10. Calculate the hydraulic conductivity of the soil in cm/s 19. The ratio of the volume of voids to the total volume of soil
a. 4.07 x 10^-3 c. 4.25 x 10^-3 a. porosity c. degree of saturation
b. 3.54 x 10^-3 d. 2.89 x 10^-3 b. void ratio d. water content

g. rasco, ce, rmp, ree

Page 1 of 3
 RASCO CIVIL ENGINEERING REVIEW
ALOJA COFFEE SHOP, LIBAS, BANGA, AKLAN
CP: 09164618841 / Landline: (036) 267 - 7343

GEOTECHNICAL ENGINEERING EVALUATION 1

Given the following soil properties: 30. The permeameter in a falling head permeability test setup
involves a cylindrical soil sample 50 mm in dia and a height of 200
Gs = 2.67 mm. The hydraulic head in the 10-mm dia standpipe through which
e = 0.45 test water passed dropped from 900 mm to 500 mmm in one-
S = 40% minute of observation. In that duration, the water collected in the
graduate was recorded at 1.5 li. Evaluate the coefficient of
Calculate: permeability of the soil sample in cm/s
a. 0.00857 c. 0.00784
20. The unit weight of the soil (kN/m^3) b. 0.00724 d. 0.00932
a. 18.52 c. 19.28
b. 18.06 d. 21.11 A confined aquifer is recharged by a continuous supply of water
from the certain source. The hydraulic conductivity of the aquifer is
21. The dry weight of the soil (kN/m^3) 35 m/day with a porosity of 25%. The piezometric (head) surface in
a. 18.52 c. 19.28 the two observation wells 1 000 m apart are at elevation 75 m and
b. 18.06 d. 21.11 65 m respectively from the common datum. The aquifer has an
average thickness of 4 m and an average width of 4 km. Determine
22. The unit weight of the soil when fully saturated
a. 18.52 c. 19.28 31. nearest value to the rate of flow of water through the aquifer, in
b. 18.06 d. 21.11 cu. m per day.
a. 5500 c. 5200
23. A soil has a specific gravity of 2.5, degree of saturation of 40%, b. 5600 d. 5800
and void ratio of 0.40. Obtain the unit weight of the soil in kN/m^3
a. 18.21 c. 19.32 32. nearest value of the seepage velocity in m/day
b. 17.52 d. 18.64 a. 1.4 c. 1.3
b. 1.5 d. 1.2
A stratified soil consists of the following layers:
33. nearest value of the time of travel from the head of aquifer to a
Layer k, cm/s Thickness, cm point 4 km downstream in days
1 3 x 10^-4 4 a. 2667 c. 3077
2 2 x 10^-5 5 b. 2857 d. 3333
3 3 x 10^-3 3
4 3 x 10^-3 3 34. A pile of sand keeps from spreading out like a liquid because the
weight of the sand keeps the grains stick together in their current
Evaluate: arrangement, mostly out of static friction. This weight and pressure
is called
24. Equivalent coefficient of permeability for flow in the horizontal a. adhesion c. cohesion
direction, cm/s b. internal friction d. effective stress
a. 0.00214 c. 0.00129
b. 0.00324 d. 0.00186 35. Which of the following is not a soil component?
a. organic materials c. gas
25. the rate of flow per meter width of the deposit in cu cm/s if the b. minerals d. none of these
hydraulic gradient for the soil formation is 0.70
a. 1.35 c. 4.58 36. Atterberg limit tests is done on aggregates that pass through
b. 3.32 d. 2.82 what sieve size?
a. 20 c. 60
26. Evaluate the discharge of the aquifer in cu. m/day b. 40 d. 30
a. 0.325 c. 0.095
b. 0.117 d. 0.228 A soil in its natural state has a moisture content of 30% and a unit
weight of 16 kN/m^3. The specific gravity of the soil particles is 2.50.
A soil sample has a dry unit weight of 17 kN/m^3 and void ratio of Determine
0.60. Evaluate
37. The void ratio of the soil sample
27. The specific gravity of the soil solids a. 0.973 c. 0.677
a. 2.77 c. 2.56 b. 0.875 d. 0.99
b. 2.44 d. 2.65
38. the dry unit weight
28. the unit weight of the sample in kN/m^3, when fully saturated a. 12.1 c. 12.3
a. 20.68 c. 2.56 b. 10.8 d. 13.6
b. 19.62 d. 18.62
39. the degree of saturation
29. hydraulic gradient of the soil at critical condition a. 78.6 c. 75.6
a. 1.45 c. 1.38 b. 90.2 d. 62.3
b. 1.11 d. 1.23

g. rasco, ce, rmp, ree

Page 2 of 3
 RASCO CIVIL ENGINEERING REVIEW
ALOJA COFFEE SHOP, LIBAS, BANGA, AKLAN
CP: 09164618841 / Landline: (036) 267 - 7343

GEOTECHNICAL ENGINEERING EVALUATION 1

b. 68.6 d. 65.8
40 Calculate the void ratio of a soil sample with porosity of 0.25.
a. 40.67% c. 20% 51. A particular station has the following earthwork cross-section.
b. 30% d. 33.33%
9.0 4.5 4.5 𝑥
+ 2.0
41. A soil sample has a water content of 15% and moist unit weight 𝑦 +4.0 +2.0 +1.0
of 18 kN/m^3. The Gs=2.65. Obtain the void ratio of the soil
a. 0.661 c. 0.632 If the width of the road base is 9 m and the side slopes are 1V:
b. 0.523 d. 0.487 1.5H,the quantity of x and y is equal to:
a. 6, 3 c. 5, 4
42. A practice or procedure used to asses the particle size b. 3, 6 d. 4, 5
distribution (gradation) of a granular material. The size distribution is
often of critical importance to the way the material performs in use. With the use of an engineer’s level, the reading on a rod held 100 m
a. consolidation test c. liquid limit test away was found to be 1.56 m. The bubble was leveled through 4
b. standard penetration test d. sieve analysis spaces on the level tube and the rod reading decreased to 1.54 m.
Determine
43. the ratio of the volume of water to the volume of voids
a. porosity c. degree of saturation 52. angle that the bubble on the tube was deviated in seconds of arc
b. void ratio d. water content a. 41.25” c. 32.33”
b. 21.25” d. 10.77”
A 300 mm dia well penetrates 27 m below the static water table.
After 24 hours of pumping 69 li/s, the water table in two observation 53. angular value of one space of the tube in seconds of arc?
wells located 35 m and 95 m from the well showed drawdowns of a. 17.65” c. 12.66”
1.1 m and 0.5 m respectively. Calculate b. 10.31” d. 14.87”

44. the discharge in cu. m per day 54. radius of the level tube if one space on the tube is 1 mm?
a. 5962 c. 4259 a. 20 m c. 15 m
b. 5692 d. 6249 b. 30 m d. 10 m

45. coefficient of permeability of the soil in m/day 55. A sight is taken with an engineer’s level at rod held 100 m away
a. 68.7 c. 55.4 and an initial reading of 1.83 m was observed. The bubble is then
b. 46.3 d. 60.27 level through five spaces on level tube and the reading is 1.91 m.
What is the sensitivity of bubble tube in seconds of arc?
46. value of transmissivity of the soil in m^2/day a. 24” c. 42”
a. 1524 c. 1724 b. 33” d. 38”
b. 1579 d. 1369
56. The photograph was exposed with a 6-in focal length camera at a
A 7.6 m thick clay layer is underlain by 15.2 m of sand to the ground. flying height above mean sea level of 10,000 ft. What is the photo
The water table is level with the ground surface. The saturated unit scale at point A if the elevation of point A on the ground is 2500 ft
weight of sand is 21.2 kN/m^3 and its dry unit weight is 18.2 above mean sea level?
kN/m^3. The saturated unit weight of clay is 18.8 kN/m^3. The a. 1:7,500 c. 1:35,000
water table is lowered to 7.6 m below the ground and the sand b. 1:25,000 d. 1:15,000
above the water table have a degree of saturation decreased by
20%. Solve 57. Points A, B, and C are three triangulation stations whose
positions were determined by the angles measured at station B to A
47. The effective pressure (kPa) at the midheight of the clay layer and C respectively. Station A is 1200 m from B with azimuth of 140
before the lowering of the water table degrees. Station C is 965 m from B with azimuth of 286deg30min. A
a. 207.3 c. 256.4 sounding at F was taken from a boat and the angles BFA and BFC
b. 324.3 d. 393.7 were measured simultaneously by two sextants from the boat and
was found to be 28deg15min and 22deg30min, respectively. How far
48. The effective pressure (kPa) at the midheight of the clay layer is F from B?
after the lowering of the water table a. 1956 m c. 1796 m
a. 261.4 c. 236.8 b. 1875 m d. 2002 m
b. 277.3 d. 297.4
58. The area bounded by the waterline of a reservoir and the
49. The effective pressure (kPa) at the midheight of the clay layer contours at an interval of 1.7 m are as follows:
when the water table is at the clay surface and assuming that all A1=15430 m^2 A2=12980 m^2
sand has the same degree of saturation A3=10650 m^2 A4=8540 m^2
a. 314.7 c. 347.3 A5=5270 m^2 A6=2180 m^2
b. 425.2 d. 369.8
Solve the volume of the reservoir by prismoidal formula in cu. m
50. The path of the typhoon “Dindo” passes thru Batanes Island at a a. 78911 c. 74681
certain location whose depth of water above the bottom of the sea b. 75108 d. 77290
equal to 150 m. Determine the approximate velocity (kph) of the
wave propagation in kph.
a. 74.6 c. 77.8
g. rasco, ce, rmp, ree
Page 3 of 3
 CALIFORNIA DEPARTMENT OF TRANSPORTATION
(CAL TRANS)

UNIFIED SOIL CLASSIFICATION SYSTEM

UNIFIED SOIL CLASSIFICATION AND SYMBOL CHART LABORATORY CLASSIFICATION CRITERIA

COARSE-GRAINED SOILS
(more than 50% of material is larger than No. 200 sieve size.)
Clean Gravels (Less than 5% fines)
D50 D30
Well-graded gravels, gravel-sand cu =- - greater than 4; Cc = between 1 and 3
GW GW D10 0 10 x D50
mixtures , little or no fines
GRAVELS
More than 50% Poorly-graded gravels , gravel-sand
GP GP Not meeting all gradation requirements for GW
of coarse mixtures, little or no fines
fraction larger Gravels with fines (More than 12% fines)
than No. 4
sieve size Atterberg limits below "A"
GM Silty gravels, gravel-sand-silt mixtures GM Above "A" line with P.I. between
line or P.I. less than 4
4 and 7 are borderline cases
Clayey gravels, gravel-sand-clay Atterberg limits above "A" requiring use of dual symbols
GC GC
mixtures line with P. I. greater than 7
Clean Sands (Less than 5% fines)
D50 D30
Well-graded sands, gravelly sands, cu =- - greater than 4; Cc = between 1 and 3
SW SW D10 0 1oxD60
little or no fines
SANDS
50% or more Poorly graded sands, gravelly sands ,
SP
of coarse little or no fines SP Not meeting all gradation requirements for GW
fraction smaller Sands with fines More than 12% fines
than No. 4
sieve size Atterberg limits below "A" Limits plotting in shaded zone
SM Silty sands , sand-silt mixtures SM
line or P.I. less than 4 with P.I. between 4 and 7 are
borderline cases requiring use
Atterberg limits above "A"
SC Clayey sands, sand-clay mixtures SC of dual symbols.
line with P. I. greater than 7
FINE-GRAINED SOILS
(50% or more of material is smaller than No. 200 sieve size.) Determine percentages of sand and gravel from grain-size curve. Depending
on percentage of fines (fraction smaller than No. 200 sieve size),
Inorganic silts and very fine sands, rock coarse-grained soils are classified as follows:
ML flour, silty of clayey fine sands or clayey Less than 5 percent .................................... GW, GP, SW, SP
SILTS silts with slight plasticity More than 12 percent ... . .............................. GM, GC, SM, SC
AND 5 to 12 percent ................... Borderline cases requiring dual symbols
CLAYS Inorganic clays of low to medium
Liquid limit CL plasticity, gravelly clays, sandy clays,
less than silty clays , lean clays PLASTICITY CHART
50%
Organic silts and organic silty clays of 60
OL
low plasticity
~
~
50
,,/
Inorganic silts, micaceous or
~ CH /
MH diatomaceous fine sandy or silty soils ,
>< 40
/
SILTS elastic silts w V" ALINE:
AND
CLAYS Inorganic clays of high plasticity, fat
C
~ 30
Vp1 = on(LL-20)

Liquid limit
CH
clays
>-
I-
u 20
CL ,,/ MHloH
50%
or greater
j:: /
Organic clays of medium to high
(/)
<( 10
/
OH ...J
plasticity, organic silts II.. CL+ML ./ ML&OL
I
00 10 20 30 40 50 60 70 80 90 100
HIGHLY
ORGANIC PT Peat and other highly organic soils LIQUID LIMIT (LL) (%)
SOILS