Scribd
Upload
27 views1 page

CE 08 Midterm

The document contains a midterm exam with multiple engineering problems involving structural analysis and design. Problem 1 involves calculating the maximum allowable load for a beam using two different methods. Problem 2 involves analyzing a reinforced concrete girder considering different load cases and support conditions. Calculations are required for steel reinforcement at different locations, shear reinforcement spacing, and additional reinforcement due to torsion. Problem 3 involves calculating deflection of a continuous beam loaded at different points over time.

Uploaded by

The one guy
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
27 views1 page

CE 08 Midterm

The document contains a midterm exam with multiple engineering problems involving structural analysis and design. Problem 1 involves calculating the maximum allowable load for a beam using two different methods. Problem 2 involves analyzing a reinforced concrete girder considering different load cases and support conditions. Calculations are required for steel reinforcement at different locations, shear reinforcement spacing, and additional reinforcement due to torsion. Problem 3 involves calculating deflection of a continuous beam loaded at different points over time.

Uploaded by

The one guy
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
You are on page 1/ 1

CE 08 – MIDTERM EXAM

INSTRUCTIONS: USE 4 DECIMAL PLACES IN ALL YOUR


SOLUTIONS AND 2 DECIMAL PLACES IN YOUR FINAL ANSWERS.
USE CORRECT UNIT. BOX YOUR FINAL ANSWERS. ****Figures at
the back****

1. A beam is loaded as shown in Figure A.


a. Using USD method and considering Figure B as its cross-
sectional area, solve for the maximum allowable load, Wu.
Use 3 – 25 mm diameter tension bars, f’c = 21 MPa and fy =
414 MPa. (15pts)
b. Using WSD method and considering Figure C as its cross-
sectional area, determine the critical stresses in concrete and
steel. Use W = 600 kN/m, f’c = 30 MPa, fy = 420 MPa, 4 – 28
mm diameter tension bars, and n = 9. (15pts)

2. The floor framing plan of a reinforced concrete structure is


shown in Figure D. When columns E and H are deleted, girder
BEHK carries the reaction of DEF at E and GHI at H or that
girder BEHK supports the beams DEF at E and GHI at H.
Beams ABC, DEF, GHI, JKL supports a 100 mm thick slab.
These beams are also subjected to superimposed dead load of
4 kPa and live load of 3.6 kPa on the slab. Beams DEF and
GHI weighs 4.5 kN/m while girder BEHK weighs 5 kN/m.
Unit weight of the concrete is 24 kN/m3. For beams DEF and
GHI, assume D and G are hinge supports while E, H, F, and I
are roller supports. Analyze girder BEHK with 350 mm width,
530 mm effective depth, compression bars, if necessary, will
have its centroid at 70 mm from the extreme concrete fiber,
and 40 mm clear concrete cover. Use f’c = 30 MPa, fy = 415
MPa, and fyt = 276 MPa. Apply STRENGTH DESIGN
3
METHOD. HINT: Reactions at D, F, G, and I are equal to
8
WuL while fixed-end moments of girder BEHK at B and K are
2
2 PuS 3WuS where Pu is the reaction from the
equal to +
3 4
beams carried by the girder and S is the distance between
beams.
a. Calculate the required steel area at the support and indicate
if it’s top or bottom bars. (10pts)
b. Calculate the required steel area at the midspan and
indicate if it’s top or bottom bars. (10pts)
c. Calculate the maximum spacing (round off to the nearest
10) of 10 mm diameter U-stirrups based on shear at critical
section. (10pts)
d. Calculate the maximum spacing (round off to the nearest
10) of 10 mm diameter U-stirrups based on torsion, Tu = 45
kN-m. Assume section is adequate for torsion. (10pts)
e. Calculate the maximum spacing (round off to the nearest
10) of 10 mm diameter U-stirrups based on combined shear at
critical section and torsion, Tu = 45 kN-m. Assume section is
adequate for torsion. (5pts)
f. Calculate the additional area of longitudinal reinforcement
due to torsion, Tu = 45 kN-m. (5pts)

3. The continuous beam is loaded as shown in Figure E and


has a cross-section shown in Figure C. Neglect beam weight.
Use f’c = 25 MPa, fy = 414 MPa, 4 – 28 mm diameter tension
bars, and n = 9. Solve for the total deflection at the point of 30
kN concentrated load after 17 months. Use R B = 153.29 kN
upward and RC = 2.81 kN downward. (20pts)

You might also like