university of bolton western international … · advanced structural analysis and design module...
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OCD57
UNIVERSITY OF BOLTON
WESTERN INTERNATIONAL COLLEGE FZE
BEng(HONS) CIVIL ENGINEERING
SEMESTER ONE EXAMINATION 2016/2017
ADVANCED STRUCTURAL ANALYSIS AND DESIGN
MODULE NO: CIE6001
Date: Tuesday 10 January 2017 Time: 10.00am to 1.00pm INSTRUCTIONS TO CANDIDATES: There are FIVE questions on this
paper. Answer ALL questions.
All questions carry equal marks. Marks for parts of questions are
shown in the brackets. This examination paper carries a
total of 100 marks. All working must be shown. A
numerical solution to a question obtained by programming an electronic calculator will not be accepted.
Extracts from EC3 for use in Question 1 are attached on Pages 11-12 of this paper.
Page 2 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 1 (a) Figure Q1(a) shows a pin – ended real strut made of Aluminium having a solid
circular cross-section of diameter 25mm and 300mm length. The strut has a small initial curvature causing a departure of yo= 0.35mm at its mid length. If an axial load P = 75kN is applied to the strut, then compute the average stress in the strut at the mid length.
(10 marks)
(b) Figure Q1(b) shows the section of an internal steel column UKC 254x254x132 to be used in a multi-story building. The column has pinned boundary conditions at each end and the inter storey height is 6m.
By using the EC3 method, assess the suitability of the section to resist an ultimate design axial compressive load of 2350kN.
(10 marks)
Total 20 marks
Question1 is continued over the page…
Figure Q1(b) UKC254x254x132
Aluminium E = 70 kN/mm2 Yield strength = 160 N/mm2 Circular cross section diameter = 25mm Length L= 300mm Initial Departure y0 = 0.35mm Axial Load P = 75kN
y0
Figure Q1(a)
h = 276.3mm b = 261.3mm tw = 15.3mm tf = 25.3mm A = 168cm2 Iy = 22500cm4 Iz = 7530cm4
iy = 11.6cm iz = 6.69cm Class 1 section Steel grade S275 Modulus of Elasticity E = 210kN/mm2 Yield Strength fy = 275 N/mm2
Page 3 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question1 continued... Additional information:
Euler Critical load 2
2
cr
crl
EIN
Design method and data sheet for buckling of columns to EC3 are attached at the end of this paper on Page 11 and Page 12. Question 2 Figure 2(a) on page 4 shows a new basketball hoop that is to be installed in the sports hall of a university. The new structure is formed using SHS200x200 steelwork as shown in the figures. The structure is to be bolted to the concrete floor using six holding down bolts as shown in Figure 2(d) on page 5. The SHS steel section has the following properties: Wall thickness 15mm Depth of section 200mm Width of section 200mm A factored horizontal force of 7kN is applied at the same location and is shown on the plan view Figure 2(b) on page 4. A factored vertical force of 12kN is applied at the location shown in the free body diagram Figure 2(c) on page 5. With proper reasoning identify the hardest working bolts and then determine the tension and shear forces carried by them. Illustrate your findings with suitable figures.
(20 marks)
Total 20 marks Question 2 continued over the page
Page 4 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 2 continued
Question 2 continued over the page…
Elevation A-A’
Figure Q2(b): Plan view of the steel
structure holding the basket ball loop
Figure Q2(a): Side view and elevation
of basketball hoop structure
Page 5 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 2 continued…
Please turn the page
Figure Q2(c): Free body Diagram steel structure holding the basket
ball loop
Figure Q2(d): Section B-B’ Plan view of base plate
All dimensions are in mm
Page 6 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 3 A composite floor construction consists of a concrete floor slab supported on a steel beam as shown in Figure Q3. The steel beam is propped during casting of the concrete, so that, when the concrete has hardened, the props are removed and all loading is carried by composite beam action.
Figure Q3
The beam is simple supported over a span of 8.0m and carries the following factored uniformly distributed loads: During construction (steel section alone carries loads): 8kN/m Dead Load + 15kN/m Imposed Load In service (Loads are carried by the composite action): 13kN/m Dead Load + 20kN/m Imposed Load
i. Find the maximum working stress and maximum deflection of the beam during construction.
(3 marks)
ii. Transform the composite section to an equivalent steel beam. Find the position of the neutral axis, the value of the moment of inertia, Iy,comp, and the values of elastic section modulus, Wel,y,comp, for the transformed beam.
(10 marks)
Question 3 continued over the page
y y
1200mm
150mm
260mm
Concrete slab 1200mm x 150mm E = 13.3 kN/mm2 fcd= 16.7N/mm2
Steel beam 254x146x43 kg/m UB Grade S275 Iyy = 6540cm4 Area = 54.8cm2 E = 205 kN/mm2
Page 7 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 3 continued
iii. For the in-service condition, find the maximum stress in the steel, the
maximum stress in the concrete and the maximum deflection of the composite beam
(5 marks)
iv. Check whether the stresses in steel and concrete are within the allowable limits.
(2 marks) DATA The central deflection of a simply supported beam carrying a uniformly distributed load w per unit length is given by:
EI
wL
384
5 4
Total 20 marks
Please turn the page
Page 8 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 4
pM2
pM5.1
pM2
Figure Q4
Figure Q4 shows a rigid-jointed frame ABCDE fixed to supports at A and E. The plastic moment of resistance of the columns AB and BCD is 2Mp each and the plastic moment of resistance of the beam DE is 1.50Mp. The frame carries a vertical
point load of W kN at C and a horizontal point load of 2
WkN at B.
(a) Find the values of MP which correspond to the following collapse mechanisms:
i. Plastic hinges at B, C and D. ii. Plastic hinges at A, C and E. iii. Plastic hinges at A, B, D and E.
(13 marks) (b) Using suitable supporting calculations, draw the bending moment diagram for
the critical collapse mechanism showing values at A, B, C, D and E (7 marks)
Total 20 marks Please turn the page
7m
3m
6m
4m
A
B DC
E
2
WkN
WkN
Page 9 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
At transfer 0.6 fck in compression; 1 N/mm2
in tension
In service 0.45 fck in compression; 3.8 N/mm2
in tension
Question 5
Figure Q5
Figure Q5 shows the cross-section of a pre-stressed concrete beam. The beam contains twelve pre- stressing strands (13.5 mm diameter, 12 wire super strands) at a height of 150mm from the bottom of the beam.
The beam supports dwellings and so the proportion of the variable load to be considered in the quasi permanent loading condition is 0.3. In service, the beam is simply supported over a span of 8.0m and carries the following loads:
Permanent load (including beam self-weight) 50 kN/m
Variable load 35 kN/m Characteristic breaking load of one strand = 186KN Initial pre-stress = 70% of UTS Pre-stress losses = 25% of initial pre-stress INA = 8.10X1010 mm4 Concrete strength at transfer fck = 35 N/mm2 Concrete strength in service fck = 45 N/mm2
Limiting stresses in concrete:
Question 5 continued over the page…
............
1400mm
400mm
700mm
700mm
N A
643.33mm
150mm
Page 10 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
Question 5 continued…
(a) Calculate the stresses in the concrete at the top and bottom of the beam: (i) at transfer; (ii) in service under quasi-permanent loads
(13 marks)
(b) Draw the distribution of stress over the height of the beam in transfer and in
service under quasi-permanent loads (4 marks)
(c) Compare the calculated values of stress in the concrete with the limiting values
of stress in the concrete: (i) at transfer; (ii) in service under quasi-permanent loads. Comment on the adequacy of the beam
(3 marks)
Total 20 marks
END OF QUESTIONS
Please turn the page for supplementary information
Page 11 of 12 University of Bolton Western International College FZE BEng(Hons) Civil Engineering Semester One Examination 2016/2017 Advanced Structural Analysis and Design Module No. CIE6001
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