BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI
HYDERABAD CAMPUS
 Course: (CE G617) Advanced Structural Analysis                              FIRST SEMESTER 2015-2016
 Maximum Marks: 60                                                           Date: 03.12.2015
 Max Duration: Part I - 120 Min , Part II – 60 Min                           Component Weightage: 30%
                                     Comprehensive Exam (Closed book)
                                                  PART – I
Note: 1. Answer all questions.
      2. Non programmable scientific calculators are allowed.
      3. Use of Mobiles / electronic gadgets is strictly prohibited.
      4. Notations used are standard and will have their usual meaning.
      5. Assume any suitable data, if necessary.
1. Analyze the structure with combination of beam and steel rod as shown in Figure 1 using direct
   stiffness method. The beam has EI= 1.44×104 KN-m2 and is inextensible. The steel rod has EA=
   1.25×104 KN. (08 marks )
                                                                  Figure 2
                Figure 1
2. Find the bar forces for all members in the plane truss in Figure 2. Assume all bars to have equal axial
   rigidity EA. If the bars are force-fitted due to bar ‘2’ being short by 5mm (fabrication error).
   Also include the effect of the applied loads F1=50 kN and F2=225 kN. Use the Flexibility method,
   (08 marks)
3. Use the Direct Stiffness Method to analyze the structure shown in Figure 3. However, replace the L-
   shaped bracket with load P with its equivalent loads at the midspan of member a-b. E is uniform, and
   the relative values of I are shown in Figure. Neglect all axial deformations, i.e., assume that all
   members are axially inextensible. What are the unknown nodal displacements for this problem? Set
   up the stiffness equations {P} = [K] {Δ} for these free degrees of freedom but do NOT solve these for
   the displacements. (08 marks )
4. Analyse the frame shown in Figure 4 using Displacement transformation method for displacements
   (08 marks )
                        L/4
                                P                      Figure 3
           L/4
                                       b                                                                         Figure 4
       a           4I                                  2I         c
                                                                                                             20 kN-m           30 kN-m
                                                                  3I       P/L        L                           4m
                                                                                                                  (2I)
                                                                                                       4m                            4m
                                                                                                       (I)                           (I)
                                                                  d
             L/2              L/2                  L
5. Answer the following:
    a) Discuss the approach used in matrix method of analysis of structures to apply body or surface
       loads (such as spread load to a beam, plane frame, etc.) (2 marks )
    b) Discuss the approach used in matrix method of analysis of structures with inclined roller
       supports (2 marks )
    c) Obtain the horizontal deflection at top of the shear wall shown in Figure 5. You may directly
       solve for only horizontal deflection at top using the basics you know. Or you may make use of
       the following element stiffness / flexibility for shear wall element given below. Use proper load
       vector and boundary conditions depending on the shear element you choose. (4 marks )
       W
                                                                         Figure 5
                                    Flexibility Matrix                              Stiffness matrix                   ar = shear area
           Shear wall element with two d.o.f.
                                                                       Stiffness matrix
     Shear wall element with four d.o.f.
                                               PART – II
Note: 1. Answer all questions.
      2. Matlab programs for beam, framed structures and programmable device (computers) are allowed.
      3. Use of Mobiles and internet are strictly prohibited.
      4. Notations used are standard and will have their usual meaning.
      5. Assume any suitable data, if necessary.
      6. Write the steps and the results in the answer sheets
6. Figure 6 shows two identical horizontal beams, AB and CD, at right angles to each other in plan, and
    monolithically connected at E, corresponding to the mid-span locations of the two beams. Assume
    both beams to have the same span L= 5m and the same flexural rigidity EI = 80000 kN-m2, and
    torsional rigidity GJ = 0.2EI, with fixity (restraints against flexure and torsion) at both ends.
    The beam AB is subject to a concentrated load of magnitude P=130kN, acting at the quarter-span
    point F, as shown.
    a) List the displacements and the member forces (7 marks)
    b) Sketch the likely shapes (without values) of the shear force, bending moment and twisting moment
    diagrams of AB and CD. (3 marks)
   [Hint: Only 3 global coordinates are required!]
   [You may make use of the grid element stiffness given below]
7. Figure 7 shows plane frame structure under lateral loading. Find the horizontal displacements at P, O
   and N. Also find the maximum moment value and its location. Assume, E=200000000000 N/m2,
   All vertical members have b = 0.4 m and d = 0.4 m;
   All horizontal members have b = 0.3 m and d = 0.4 m;                                   (10 marks)
                   Figure 6
                                                                          Figure 7
                                                                     Grid element and Transformation matrix
  Grid element stiffness matrix