QUESTION 1
Figure 1 shows a beam assembly.
(a) Draw and label the free body diagram for the beam.
(b) Calculate the support reaction forces at A and B. Draw the shear force and bending moment diagrams.
(c) If the beam's cross sectional area has a dimension of 150 mm x 150 mm, calculate the largest bending stress in the beam.
QUESTION 2
A test specimen is loaded in tension (tensile test). The specimen has a diameter of 10 mm and an initial gauge length (Lo) of 150 mm. Table 1 below is the load - gauge length data obtain from the tension test.
Table 1: Load - gauge length data
|
Load (kN)
|
Gauge Length, (mm)
|
|
0
|
150.00
|
|
5
|
150.03
|
|
10
|
150.06
|
|
15
|
150.09
|
|
20
|
150.12
|
|
25
|
150.20
|
|
30
|
150.62
|
|
35.3
|
152.00
|
|
35.6
|
153.00
|
|
31.9
|
155.30
|
a) Using the data in the table, calculate the engineering stress and engineering strain for each load. Tabulate your result according to the table below:
|
Load (kN)
|
Gauge Length, (mm)
|
Engineering stress (MPa)
|
Engineering strain
|
|
|
|
|
|
b) Using the engineering stress and engineering strain data calculated previously, plot a stress strain diagram on a graph paper.
c) From the stress - strain diagram plotted, calculate the stiffness of the material being tested.
d) Using the stress - strain diagram, determine the yield strength using the 0.2% offset method.