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					CONFIDENTIAL                                                               AP/OCT 2007/QSD133/103




                                 UNIVERSITI TEKNOLOGI MARA
                                     FINAL EXAMINATION




      COURSE                      :     PRINCIPLES OF STRUCTURES
      COURSE CODE                 :     QSD133/103
      EXAMINATION                 :     OCTOBER 2007
      TIME                        :     2 HOURS




INSTRUCTIONS TO CANDIDATES

 1.          This question paper consists of five (5) questions.

2.           Answer four (4) questions only in the Answer Booklet. Start each answer on a new page.

3.           Do not bring any material into the examination room unless permission is given by the
             invigilator.

4.           Please check to make sure that this examination pack consists of:

                i)   the Question Paper
               ii)    a two - page Appendix
              iii)   an Answer Booklet - provided by the Faculty
              iv)    two sheets of graph paper - provided by Faculty




                      DO NOT TURN THIS PAGE UNTIL YOU ARE TOLD TO DO SO
                             This examination paper consists of 5 printed pages
© Hak Cipta Universiti Teknologi MARA                                                 CONFIDENTIAL
CONFIDENTIAL                                                     AP/OCT 2007/QSD133/103




QUESTION 1

a) Explain briefly of the following terms:

   i) Dead Load
   ii) Live / Impose Load
                                                                               (5 marks)

b) Determine the position of the center of gravity for the shape shown in Figure (1a) from
   point of reference P.


                       2m dia. void




                8m                                                15m



                4m


                                                                               (10 marks)

                                        Fiaure 1a

c) Figure (1c) shows a frame structure loaded with point loads. Determine the reaction at
   each supports.

                                50kN


                                                                  50kN



                                                                             2m




                                         Fiaure 1c                R
                                                                               (10 marks)


© Hak Cipta Universiti Teknologi MARA                                      CONFIDENTIAL
CONFIDENTIAL                                                            AP/OCT 2007/QSD133/103




QUESTION 2

a) Figure (2a) shows the loading system on the beam,

   i)     Calculate the reaction at the two supports L and R.

   ii) Draw the Shear Force and Bending Moment Diagram,

   iii) Determine the magnitude and location of maximum bending moment.

                                                                                      (25 marks)


                          Height of brickwall = 2.5m
                          Thickness of Brick Wall = 225mm
                          Density of Brick Wall = 20kN/m3                              15kN


                       10kN

                                                            BRICKWALL                         2.5m


          7kN/m Reinforced Concrete Beam

                              2.0m              3.0m
        1.0m    1.0m                                            2.0m           2.0m

                                                                         R
                                          Fiqure 2a



QUESTION 3

a) A timber beam has to support loading which will cause a maximum bending
    moment of 30 x 10 6 Nmm. Design the appropriate size of beam. Given, the permissible
    bending stress of timber is 7N/mm2.

                                                                                      (10 marks)

b) The singly reinforced concrete beam shown in Figure (3b) is required to resist ultimate
   bending moment of 750kNm. If the beam is composed of grade 35 concrete and high
   yield steel reinforcement, check the section size and determine the area of steel
   required.

    i)         Check the section size.
    ii)        Determine the area of steel required.


© Hak Cipta Universiti Teknologi MARA                                           CONFIDENTIAL
CONFIDENTIAL                                                        AP/OCT 2007/QSD133/103



                                            b=450mm




                 d=700mm




                                           Fiqure 3b

   iii)      Sketch the cross-section of the beam showings all the details.

             Given:
             Concrete cover        = 20mm
             feu                   = 35 N/mm2
             fy                    = 460 N/mm2
                                                                                  (15 marks)


QUESTION 4

a) Using suitable sketches explain the behaviour of the following columns when they are
   subject to loading.

    i) Short Column
    ii) Slender Column
                                                                                   (5 marks)

b) A short braced reinforced concrete column is required to support an ultimate axial load of
   3500kN.

    i)    Calculate the required size of a square column and choose the suitable main bars.

                                                                                  (10 marks)

    ii) Calculate the required diameter of a circular column and choose the suitable main
        bars.
                                                                              (10 marks)


© Hak Cipta Universiti Teknologi MARA                                         CONFIDENTIAL
CONFIDENTIAL                                                    AP/OCT 2007/QSD133/103




   Given:

   Concrete cover                 25mm
   Concrete grade                 G30
   Reinforcement                  Mild Steel
   Percentage of steel        -    2%


QUESTION 5

a) Using suitable sketches explain the following terms:

   i) One-way slab
   ii) Two-way Slab

                                                                               (8 marks)

b) Figure 5b shows a one-way reinforced concrete slab which is subjected to an ultimate
   moment of 50kNm/m including its self-weight. Using the simplified stress block formula
   given in BS 8110 Parti, determine the following:

    i)   The spacing of the main bars.

    ii) The size and spacing of the distribution bars.
                                                                              (17 marks)

    Given:

    Concrete cover            25mm
    Concrete grade            G30
    Reinforcement             High Yield Steel


                                                 1000mm




                                                                               12mm 0
 350mm                                                                         main bars


                                               Figure 5b




                                        END OF QUESTION PAPER

© Hak Cipta Universiti Teknologi MARA                                     CONFIDENTIAL
CONFIDENTIAL                                APPENDIX 1                AP/OCT 2007/QSD133/103

                                        LIST OF FORMULAE


Reinforced Concrete Beam

K' = 0.156

K = M/Fcubd2


For Singly Reinforced Concrete Beam, K < K'

z = d[0.5 + V(0.25-K/0.9)]

z<0.95d

As = M/0.87fyz


Short Braced Axially Loaded Column

BS 8110 equation 38(a) : N = 0.4fcu (A g - Asc) + 0.75 Ascfy


Timber Beam

M = fz

z = bd2/6


                            Areas of Round Bar Reinforcement (mm2)

                                               Number of Bars
Diameter
                 1          2           3     4          5       6       7       8       9
  (mm)
    6         28         57         85      113    142         170    198     226     255
    8         50         101        151     201    252         302    352     402     453
    10        79         157        236     314    393         471    550     628     707
    12        113        226        339     452    565         678    791     904     1017
    16        201        402        603     804    1005        1206   1407    1608    1809
    20        314        628        942     1256   1570        1884   2198    2512    2826
    25        491        983        1474    1966   2457        2946   3439    3932    4423
    32        804        1608       2412    3216   4020        4824   5628    6432    7236
    40        1257       2513       3770    5027   6283        5740   8796    10053   11310


© Hak Cipta Universiti Teknologi MARA                                          CONFIDENTIAL
CONFIDENTIAL                               APPENDIX 2                 AP/OCT 2007/QSD133/103




               Areas of Round Bars Reinforcement spaced at various centers
                                  (mm2 per lm width)

Diameter                                        Spacing (mm)
(mm)            75       100       125   150     175    200    225       250    275    300

6             377       283       226    188    162     141    126      113    103    94
8             670       503       402    335    287     251    223      201    183    168
10            1047      785       628    524    449     393    349      314    286    262
12            1508      1131      905    754    449     393    349      314    286    262
16            2681      2011      1608   1340   1149    1005   894      804    731    670
20            4189      3142      2513   2094   1795    1571   1396     1257   1142   1047




© Hak Cipta Universiti Teknologi MARA                                          CONFIDENTIAL