19/09/2011
ENB 371 : Geotechnical Engineering 2
Week 9 - Practice Questions
1
Q1)
B x L=8mx18m
Df=3m
B =8m
Cu = 120kN / m
= 18kN / m
u = 0
2
Assume no water table effect
3
Mayerhof Bearing Capacity Equation
qu = c' N c Fcs Fcd Fci + qN q Fqs Fqd Fqi + 0.
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 12 PRACTICE QUESTIONS Rock mechanics
Q1. A sandstone rock mass which is very favourable for tunnel, fractured by 2 joint sets
plus random fractures, average RQD is 70%, averag
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 11 PRACTICE QUESTIONS Pile foundations 2
Q1. As shown in the Figure Q1, a pile was driven into the ground where the sand fill was placed recently. The water table coincides wi
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 10 PRACTICE QUESTIONS Pile foundations 1
Q1. A 15 m long concrete pile with a cross section of 0.45 m x 0.45 m fully embedded in
sand. For the sand, given: unit weight, = 17 k
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 9 PRACTICE QUESTIONS Shallow Foundation - 3
Q1. Determine the net ultimate bearing capacity of mat foundations with the following
characteristics: (Use Mayerhofs bearing capac
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 8 PRACTICE QUESTIONS Shallow Foundation - 2
Q1. An eccentrically loaded foundation is shown in the following figure. Use FS of 4 and
determine the maximum net allowable load t
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 7 PRACTICE QUESTIONS Shallow Foundation
Q1. A strip footing is to be designed to support a dead load of 500 kN/m and an imposed load of 300 kN/m at a depth of 0.7 m in sand. C
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 6 PRACTICE QUESTIONS Time-dependent Consolidation
Q1.
Answer the following questions.
(i)
Tv = cvt / H 2 , What is the definition of H in this equation?
(ii)
Give typical unit
5/09/2011
ENB 371 : Geotechnical Engineering 2
Week 6 Practice Questions
1
Q1
(i)
Tv =
cv t
H
What is the definition of H in this equation?
H is the length of the average longest drainage path during consolidation (length of
the drainage path)
(a)In the c
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 5 PRACTICE QUESTIONS Consolidation settlement
Q1. Using the e vs log ' graph shown in Figure 1, determine the pre-consolidation pressure (c'), the compression index (Cc) and t
Queensland
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 4 PRACTICE QUESTIONS Elastic settlement of soil
PRACTICE
Q1.
A square foundation measuring 3x3 m, supported by a layer of sand is shown in
ng
Figure 1. Calculate th
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 3 PRACTICE QUESTIONS Subsurface stress increment
Q1.
A steel storage tank 20 m in diameter will be used to hold a liquid petroleum
product. When filled, the tank causes a bear
Queensland University of Technology
QUT
ENB371: Geotechnical Engineering 2
WEEK 2 PRACTICE QUESTIONS Review of ENB272
Q1.
A site investigation revealed a uniform deposit of clay. A sample of the clay 76 mm
high and 38 mm diameter taken from above the wate
5/08/2011
Q1
(i)
76 mm
Bulk soil mass = 175 g =0.175 kg
Dry soil mass = 143 g = 0.143 kg
Specific gravity of soil, Gs = 2.71
V=
38 mm
D2
h
4
38 76
4 1000 100
2
V=
V = 8.62 10 5 m3
Bulk density( b ) =
Bulk unit weight
Q1
(ii)
Bulk mass
0.175
=
= 2030
16/08/2011
ENB 371 : Geotechnical Engineering 2 Week 3 Practice Questions
1
Q1
Without the pressure from the tank (When the tank is empty)
Ground
20m
= . /
5m
5m
=
.
/
At 10 m depth (at A & D) =
A
= . = .
D
/ . /
. = -
+ . =
. / . -
= . =
2
1
16/08/2011
Q
REVIEW OF:
ENB371: Geotechnical Engineering 2
Content of the lecture series -1
Review of ENB272: Geotechnical Engineering 1 (week -1)
- Phase relationships in soils
- Geostatic stresses
Stress increments in the soil due to loading at the surface(Week -2
12/09/2011
ENB 371 : Geotechnical Engineering 2 Week 7 Practice Questions
1
Q1
Q
Df = 0.7 m C' = 0 = 40
w
sat
= 20 kN/m3
= 9.8 kN/m3 = 17 kN/m3
FS = 3.0
Q=500+300=800 kN/m
Df = 0.7 m
Water table may rise to foundation level d=0
B
d
B?
According to Terzag
Consolidation
Consolidation settlement in soils -2
(Rate of consolidation settlement)
Excess pore water pressure distribution with
time and depth
t =
ue
t = t1
2H
2H
t = t2
ENB371: Geotechnical Engineering 2
Chaminda Gallage
Chapter 1.13
Chapter 7
Terzagh
22/08/2011
ENB 371 : Geotechnical Engineering 2
Week 4 Practice Questions
1
Q1
Se =
(
q0 Be I G I F I E
1 s2
E0
)
B = L = 3m
Be =
4 BL
=
4 3 3
= 3.38 m
2
1
22/08/2011
Influence factor for the variation of Es with depth, IG
E
H
20
16,000
=
= 5.92, 0 =
= 11
Introduction (1)
Consolidation
Consolidation settlement in soils -1
Total settlement in soil due to loading
Deformation of soil and
rock grains
Compression of air and
water in voids
Drainage of water and
air from voids allowing
compression of soil
skel
Introduction (1)
Loading on the surface causes deformation/settlement in sub-soils
Elastic settlement in soils
Large Distributed Weight Low Weight Very Large Concentrated Weight
ENB371: Geotechnical Engineering 2 Chaminda Gallage
Weak Soil Weak Rock
Stron
10/10/2011
Introduction -2
Introduction to Rock Mechanics
Rock mechanics is applied to various engineering disciplines:
Civil
Mining
Hydropower
Petroleum.
In civil engineering, it involves:
ENB371: Geotechnical Engineering 2
Chaminda Gallage
Outline of th
27/10/2011
Q1
ENB 371 : Geotechnical Engineering 2
Week 13 Practice Questions
A sandstone rock mass which is very favourable for tunnel, fractured by 2 joint
sets plus random fractures, average RQD is 70%, average joint spacing is 0.11 m,
joint surfaces a
16/10/2011
Shear strength of Rock Discontinuity
Rock Slope Stability
ENB371: Geotechnical Engineering 2
Chaminda Gallage
Shear Strength of Planar Surfaces
Bedding surface is planar having no surface irregularities or undulations.
Filling material presents
Application of geo-engineering
knowledge in designing
Shallow Foundations -3
Combined & Matt (Raft) Foundations
Field tests used in shallow foundation design
ENB371: Geotechnical Engineering 2
Combined Footings
Under normal conditions, spread footings (sq