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					CONFIDENTIAL                                                                     AP/APR2007/QSD133




                                 UNIVERSITI TEKNOLOGI MARA
                                     FINAL EXAMINATION




     COURSE                       :     PRINCIPLES OF STRUCTURES
     COURSE CODE                  :     QSD133
     EXAMINATION                  :     APRIL 2007
     TIME                         :     2 HOURS




INSTRUCTIONS TO CANDIDATES

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

2.          Answer FOUR (4) questions 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)    an Answer Booklet - provided by the Faculty
              iii)   two sheets of graph paper - provided by the Faculty




                     DO NOT TURN THIS PAGE UNTIL YOU ARE TOLD TO DO SO
                            This examination paper consists of 7 printed pages
© Hak Cipta Universiti Teknologi MARA                                                CONFIDENTIAL
CONFIDENTIAL                                                              AP/APR2007/QSD133


QUESTION 1

a) Briefly explain any two (2) of the following:

    i)     Dead Load
    ii)    Imposed Load/Live Load
    iii)   Ultimate Design Load
    iv)    Wind Load
                                                                                       (8 marks)

b) Figure Q1b shows a simply supported beam with a cross-section 300mm x 600mm
   carrying 300mm thick brickwall and a 300mm x 300mm reinforced concrete column.

    Calculate:

    i) The ultimate design load
    ii) Reactions at the support due to ultimate design load.

    Given:
    The unit weight of reinforced concrete        = 24kN/m3
    The unit weight of brickwall                  = 22kN/m3


                                        —      300mm x 300mm reinforced concrete column




                 300mm thick                300mm thick                               3.0m
                 brickwall                  brickwall

                                                                                  A
               300mm x 600mm reinforced concrete beam



                  4.0m                                    6.0m



                                   Figure Q1b
                                                                                      (17 marks)




© Hak Cipta Universiti Teknologi MARA                                         CONFIDENTIAL
CONFIDENTIAL                                                        AP/APR2007/QSD133


QUESTION 2


a) Determine the unknown reactions at the following supports:

   i) Fixed support
   ii) Smooth pin or hinged
   iii) Rollers
                                                                               (6 marks)

b) Determine the unknown reactions at each support, due to the loads carried by the
   structures as indicated in Figure Q2b(i), Q2b(ii), and Q2b(iii).


                                   5kN



                                         10kN/m


                         0.5m              1.0m



                                           Figure Q2b(i)
                                                                              (6 marks)


                                              50kN

                                   30kN                     20kN


                                                                   10 kN




                                           Figure Q2b(ii)
                                                                                (7 marks)




© Hak Cipta Universiti Teknologi MARA                                      CONFIDENTIAL
CONFIDENTIAL                                                                           AP/APR 2007/QSD133




                                                     10kN/m                                             5kN



                                  3m                              3m                            1m


                                                                                       B

                                                 Figure Q2b(iii)
                                                                                                         (6 marks)


QUESTION 3


a) For the beam shown in Figure Q3a, calculate the reaction at support A and B and draw
   the shear force and bending moment diagrams.

                  15kN                                                                                 5kN


                  I                    10kN/m                       20kN/m

                       1.0m T          3.0m           0.5m           3.5m                       1.0m
                                                      <—N«-
                                                                                       B
                                              Figure Q3a
                                                                                                       (15 marks)
b) The cantilever beam shown in figure Q3b is loaded with uniformly distributed load and
   point loads. Determine the reactions at the support and draw the shear force and
   bending moment diagram.


                                              50kN           10kN


                                  30kN/m

                                          2.0m               ^
                                                                 1.0m   k
                                                                                1.0m
                              <                          '                  4              •)


                                                 Figure Q3b
                                                                                                       (10 marks)




© Hak Cipta Universiti Teknologi MARA                                                             CONFIDENTIAL
CONFIDENTIAL                                                          AP/APR2007/QSD133


QUESTION 4


a) What is an axially loaded column?
                                                                                 (5 marks)

b) Figure Q4b shows a cross section of an axially loaded short braced column in a situation
   of mild exposure. If the column is made of grade 35 concrete and mild steel
   reinforcement determine:

    i) the maximum load that the column could safely carry and
    ii) the maximum effective height of the column, if it is to be considered as a short
        column

    Given:       N =      0.4 feu (Ag - Asc) + 0.75 Asc fy


                                                 300mm




                                        I*             *            32mm 0 MS steel
                                                                     (total 4 numbers)


                   300mm




                              %
                                        •              •

                                         T   — 25mm cover

                                         Figure Q4b
                                                                                (10 marks)




© Hak Cipta Universiti Teknologi MARA                                     CONFIDENTIAL
CONFIDENTIAL                                                          AP/APR 2007/QSD133


c) Figure Q4c shows the cross section of a timber beam. Given, the permissible bending
   stress of the timber is 6N/mm2.

    i) Determine the maximum bending moment that the beam could safely carry,
    ii) If the beam is simply supported and loaded with a uniformly distributed load w kN/m
        throughout its 3m span, determine is the maximum value of w.




                                                             100mm x 200mm
                                                             timber beam




                                        Figure Q4c
                                                                                (10 marks)




© Hak Cipta Universiti Teknologi MARA                                      CONFIDENTIAL
CONFIDENTIAL                                                               AP/APR2007/QSD133


QUESTION 5


a) Explain the behaviour of a simply supported beam subjected to loading.
                                                                                         (8 marks)

b) A 350 mm wide singly reinforced concrete beam is required to transmit an ultimate
   bending moment of 580kNm, inclusive its own weight. The beam is made of grade 30
   concrete and high yield reinforcement. Using the simplified stress block formulae given in
   BS8110 (parti),

    i) Check the section of the beam
    ii) Determine the amount of steel reinforcement need
    iii) Sketch the cross-section of the beam.

    Given:
        K'   =   0.156
        K    =   M/fcu bd 2 where5, K < K' (singly reinforced)
        z    =   d [0.5 + V(0.25 -K/0.9)]
        z    <   0.95 d
        As   =   M/0.87fy z
                                    Areas of round bar reinforcement (mm 2)

    Diameter                            Number of bars
       (mm)           1        2        3      4      5      6      7      8      9
        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
                                                                                        (17 marks)




                                        END OF QUESTION PAPER




© Hak Cipta Universiti Teknologi MARA                                             CONFIDENTIAL