THE UNIVERSITY OF BOLTON SCHOOL OF ENGINEERING. BEng (Hons) CIVIL ENGINEERING SEMESTER 2 EXAMINATION 2016/2017 ADVANCED STRUCTURAL ANALYSIS & DESIGN

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1 TW41 THE UNIVERSITY OF OLTON SHOOL OF ENGINEERING Eng (Hons) IVIL ENGINEERING SEMESTER 2 EXMINTION 2016/2017 DVNED STRUTURL NLYSIS & DESIGN MODULE NO. IE6001 Date: Thursday 18 May 2017 Time: INSTRUTIONS TO NDIDTES: There are FOUR questions For Question 3, tear out and write on the page from the exam and include it in your answer booklet Total 100 marks for the paper. Extracts from E3 to be used with Question 2 are included with this paper.

2 Page 2 of 13 Question 1. 4m 2m P 2m 2m P M p = 120 knm D M p = 360 knm 6m Figure Q1 4m E F M p = 360 knm Figure Q1 shows a rigid-jointed frame DEF fixed to a support at and pinned to a support at F. Member has M p = 120 knm, members DE and EF both have M p = 360 knm. There is a horizontal point load P at and an equal vertical point load P at D a. Find the values of P which correspond to the following collapse mechanisms: i) Plastic hinges at, and ii) Plastic hinges at, D and E iii) Plastic hinges at, and E iv) Plastic hinges at, and E (15 marks) b. Draw the bending moment diagram for the critical collapse mechanism showing the important values, and state the value of P that will cause the frame to collapse. (10 marks) (Total 25 marks)

3 Page 3 of 13 Question 2 a) Explain the difference in the mode of failure between a stocky and slender column. What is the limiting value of the non-dimensional slenderness ratio for a slender column when using the E3 method? (5 marks) b) column is laterally restrained every 3.5 m against buckling about the minor axis but has no intermediate restraints against buckling about the major axis as shown in Figure Q2. The column is considered to be pinned in both directions. The column is subjected to a design load N Ed = 1000 kn. The size of the column is UK 203x203x71 with a steel grade S275. Determine the buckling resistance of the column about both axes using E3 method. omment on the results. (20 marks) UK 203x203x71: = 90.4 cm 2 I y = 7618 cm 4 I z = 2537 cm 4 b z tf h = mm tw b = mm y y t w = 10.0 mm h t f = 17.3 mm E = 210 kn/mm 2 f y = 275 N/mm 2 Partial safety factor 1 z ross-section is lass 2 2 EI N cr 2 Total 25 Marks cr m = 1000 kn Extracts from E3 to be used with Question 2 are included in ppendix. m m m Figure Q2

4 Page 4 of 13 Question mm N 150mm 550mm Figure Q mm 180mm 740mm Figure Q3-1 shows a pre-stressed concrete beam. The beam contains seven prestressing strands (12.9mm diameter, 7 wire super strand) 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 9m and carries the following loads: Permanent load (including beam self-weight) 30 kn/m Variable load 25 kn/m haracteristic breaking load of one strand = 186 kn Initial pre-stress = 70% of UTS Pre-stress losses = 25% of initial pre-stress oncrete strength at transfer f ck = 35 N/mm 2 oncrete strength in service f ck = 45 N/mm 2 For the whole concrete section: rea = 533 x 10 3 mm 2 Second moment of area of concrete section I N = 26.5 x 10 9 mm 4 (a) Evaluate unbonded post-tensioned construction for an office building with respect to safety and sustainability considering the whole life of the structure (3 marks) (b) alculate the stresses in the concrete at the top and bottom of the beam at transfer only (6 marks) (c) Draw the distribution of stress over the height of the beam at transfer and comment on the adequacy of the beam at transfer (4 marks) (d) Without doing any further calculations, estimate and sketch the distribution of stress over the height of the beam in service under quasi-permanent loads (3 marks) Question 3 continued over the page

5 Page 5 of 13 Question 3 (continued) The in-service stress distribution of a 285mm deep pre-stressed concrete slab with strands set at height h = 65mm above the bottom of the slab is shown in Figures Q3-2 and Q3-2 (the same diagram is repeated). Tear out this page and include it in your answer booklet. dd your student number at the bottom of the page. (e) On Figure Q3-2 annotate and sketch the stress distribution in service after increasing the height of the strands above the bottom of the slab (3 marks) (f) On Figure Q3-2 annotate and sketch the stress distribution in service after additional strands have been added to increase the tensile forces (with h = 65mm) (3 marks) Figure Q3-2 Figure Q3-2 Student number.. (Total 22 marks)

6 Page 6 of 13 Question 4 PRT - EENTRI OLTED ONNETION The L shaped bracket shown in Figures Q4-1 and Q4-2 is connected to a steel column 303.4mm deep with 6 NoM20 (8.8) bolts. The bracket is formed from a U 305x165x40kg/m steel section with the following properties: Web thickness Flange thickness Depth of section Width of section 6mm 10.2mm 303.4mm 165mm factored vertical force of 70kN is applied at the location shown in the plan view of the bracket. (i) What are the in and out of plane moments in the bolt group? (3 marks) (ii) Define the bolt carrying the greatest combined shear and tensile forces; give a brief explanation for your choice. (3 marks) (iii) State the maximum shear force in the left hand bolt of bolt row b3 (i.e. b3 L). (5 marks) 600mm 303.4mm centre line of column Vertical load applied to L shaped bracket at location shown 90mm Figure Q4-1 PLN VIEW ON RKET 420mm Question 4 continued on next page..

7 Page 7 of 13 Question 4 (PRT continued) L R 90mm 70mm 70mm 73.4mm 90mm Figure Q4-2 SETIONL ELEVTION - ON OLTED ENDPLTE SHOWING SETTING OUT OF OLTS b1 b2 b3 Question 4 continued on next page..

8 Page 8 of 13 Question 4 (continued) PRT Understanding structural behaviour In answering Question 4 PRT please tear out and use the multiple choice marking sheet in ppendix Q4-1 hoose the bending moment diagram (MD) that matches the structure shown (2 marks) D Question 4 continued on next page..

Page 9 of 13 Question 4 (continued) PRT Understanding structural

rectangular reinforced concrete beams with tendons positioned in

Match the tendon profiles (1, 2 and 3) with the corresponding

Ignore the self-weight of the beam (Hint different tendon

9 Page 9 of 13 Question 4 (continued) PRT Understanding structural behaviour Q pre-stress load is applied to three rectangular reinforced concrete beams with tendons positioned in different ways. Match the tendon profiles (1, 2 and 3) with the corresponding deformed shapes of the beam (, and ). Ignore the self-weight of the beam (Hint different tendon profiles may create similar deformed shapes). (3 marks) Diagrams showing tendon profiles Diagrams showing deformed shapes Question 4 continued on next page..

10 Page 10 of 13 Question 4 (continued) PRT Understanding structural behaviour Q4-3 hoose the bending moment diagram (MD) that matches the structure shown (2 marks) Q4-4 D hoose the diagram (,, or D) that shows the structural model that matches the shear force diagram (SFD) shown (2 marks) D Question 4 continued on next page..

11 Page 11 of 13 Q4-5 hoose the bending moment diagram (MD) that matches the structure shown (2 marks) D Q4-6 hoose the bending moment diagram (MD) that matches the structure shown. (3 marks) D Question 4 continued on next page..

12 Page 12 of 13 Q4-7 hoose the bending moment diagram (MD) that matches the pin jointed structure shown. onsider the values of the bending moments given in the answer choices (3 marks) D (Total 28 marks) End of Questions

13 Page 13 of 13 PPENDIX Multiple choice answer sheet to be used with Question 4 PRT Please tear out of the exam paper and enclose with your exam script Student number: Questions ircle the correct answers Q4-1 D Q Q4-3 D 2 Q4-4 D 2 Q4-5 D 2 Q4-6 D 3 Q4-7 D 3 TOTL 17 Marks (please leave this column blank) It is essential that your answers are clear, as ambiguous answers and crossing out may make it impossible to award marks for parts of this question. END OF PPER

UNIVERSITY OF BOLTON SCHOOL OF ENGINEERING. BEng (Hons) CIVIL ENGINEERING

TW7 UNIVERSITY OF BOLTON SCHOOL OF ENGINEERING BEng (Hons) CIVIL ENGINEERING SEMESTER 2 EXAMINATION 2015/2016 ADVANCED STRUCTURAL ANALYSIS & DESIGN MODULE NO. CIE6001 Date: Thursday 19 th May 2016 Time: