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Department of Civil Engineering & Applied Mechanics
CIVE 202
Construction Materials
Assignment #1
Due: February 12, 2009
1.
To be truly effective, the three “R’s” of sustainability should be considered as a
hierarchy, not a multiple choice approach. Explain why.
2.
What are the direction indices for the vector shown below (the vector exits the cell
in the center of the right hand face):
3.
What are the Miller indices of the following plane:
4.
What are crystal imperfections? What are the sources of these defects? What are
the effects of these imperfections on the properties and behaviour of materials?
5.
(a) Define the following terms:
(i)
force
(ii)
deformation
(iii)
stress
(iv)
strain
(b) Distinguish between force and stress, and deformation and strain
(c) Why is it necessary to report the gauge length when reporting the percentage
elongation?
6.
The following information was recorded during a tension test. of a metal bar.
Extension was observed over a gauge length of 200 mm wherein the original
diameter was 15 mm.
Plot the stress-strain curve and determine modulus of elasticity, yield strength,
failure strain, and ultimate strength of the material.
Did strain hardening occur, and did the material exhibit ductility?
Load
Extension
Load
Extension
(kN)
(mm)
(kN)
(mm)
5
0.036
50
4.653
10
0.061
55
6.030
15
0.088
60
9.221
20
0.131
65
13.196
25
0.137
70
25.935
30
0.190
75
28.260
35
0.200
80
45.680
40
0.218
66
Fracture
45
2.088
0
-
7.
If the atoms in a material exhibiting a BCC configuration in a cubic unit cell have
an atomic radius of 0.143 mm, calculate the volume of its unit cell in cubic meters.
8.
Provide a list of the materials discussed in David Suzuki’s video Advanced
Materials World, and specify at least one application for each (applications which
were seen in the video and that, therefore, do not have to only pertain to the
construction industry).
9.
Describe the advantages of nondestructive testing techniques as compared to
destructive methods? Consider applications in both the laboratory and in the field.
10.
A tension strut in an A/C support is exposed to the following series of stress cycles
over an 8 hour period:
15 cycles @ 38 ksi, 20 cycles @ 42 ksi, 25 cycles @ 50 ksi, 20 cycles @ 60 ksi, 15
cycles @ 65 ksi, 18 cycles @ 55 ksi, 10 cycles @ 50 ksi, 20 cycles @ 40 ksi, 10
cycles @ 35 ksi
Using the following S-N relationship for the steel making up the strut, determine
how many days of service the strut can withstand before failure. Assume the
loading series described above continues 24 hours per day (i.e. as one load series
ends, the next begins immediately).
11.
Even though concrete cylinders are subjected to compressive load, they do not fail
in compression. Explain this statement.
12.
Why is service temperature (i.e. the temperature to which a material is exposed
during service) a particularly important property in the design of steel structures?