November 2021 Ce Board Exam Santos 2: Eview Nnovations

REVIEW INNOVATIONS NOVEMBER 2021 CE BOARD EXAM

SANTOS 2

INSTRUCTION: Select the correct answer for each of the following questions. Mark only one answer for each item by shading the box corresponding to the letter of your choice on the answer sheet provided. STRICTLY NO ERASURES ALLOWED. GOOD LUCK. NOTE:

A times B is represented by A×B or A*B. A raised to the power n is expressed as A^n. All problems are 1 point each.

Situation 1. The solid pole shown in the Figure STR-007 is loaded with a vertical load P = 25 kN and lateral load H = 0.95 kN. The pole is 3 m high, 300 mm diameter and weighs 22 kN/m3. 1. What is the maximum compressive stress at cross-section located at mid height of the pole in MPa? A. 1.33 C. 1.87 B. 0.39 D. 2.44 2. What is the maximum compressive stress at the base in MPa? A. 1.36 C. 2.89 B. 1.90 D. 2.44 3. What is the maximum tensile stress at the base in MPa? A. 1.60 C. 1.12 B. 2.23 D. 0.89 4. What is the maximum shearing stress in the pole in MPa? A. 0.0134 C. 0.0112 B. 0.0179 D. 0.0151

STR-007

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REVIEW INNOVATIONS

SANTOS 2 - CE Board November 2021

Situation 2. A curve quarter-circular beam having a diameter of 100mm is shown in figure STR-008. P = 8 kN, radius R = 0.80m and θ = 50 deg. 5. What is the maximum shear stress (MPa)due to flexure alone at cross-section A? A. 0.849 C. 1.102 B. 1.358 D. 0.679 6. What is the maximum shear stress (MPa)due to torsion alone at cross-section A? A. 2.729 C. 7.625 B. 3.813 D. 11.643 7. What is the maximum bending stress (MPa) at cross-section A? A. 20.372 C. 30.213 B. 41.903 D. 49.938

STR-008 Situation 3. A decorative beam with a tubular section is simply supported on a span of 4.5m. Concrete weighs 24 kN/m with fc’=30 MPa. Allowable tensile strength for concrete is 3.22 MPa. 8.

Which of the following most nearly gives the cracking moment of the tubular section if it has an outside diameter of 600mm and an inside diameter of 300mm in kN-m. A. 68 C. 64 B. 54 D. 59

9.

What is the maximum uniform load the beam can safely support in kN/m? A. 20 C. 35 B. 30 D. 25

10. In addition beam safely A. 56.88 B. 45.43

to its own weight, what concentrated load at midspan can the carry before it cracks? kN C. 65.23 kN kN D. 38.75 kN

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REVIEW INNOVATIONS

SANTOS 2 - CE Board November 2021

Situation 4. Refer to Figure SMN10.09. Frame ACGE is on hinged supports at A and at E. To resist the cable pull, T, the frame is braced at B and at F. Given: T = 18 kN b = 2 m

a = 1 m c = 1 m

11. Calculate the reaction (kN) at D. A. 54.0 B. 25.4

C. 108.0 D. 76.4

12. Find the stress (MPa) in the brace BD which has an outside diameter of 75 mm and is 6 mm thick. A. 83.0 C. 19.5 B. 58.7 D. 41.5 13. If brace BD consists of 2 flat bars bolted to the post AC at B using 20 mm diameter bolt, what is the average shear stress (MPa) in the bolt? A. 171.9 C. 85.9 B. 40.4 D. 121.5

Fig. SMN10.09

Situation 5. A 2 m high cantilever temporary retaining wall is subjected to active pressure, increasing from 3 kN/m at the top (free end) to 12 kN/m at the base (fixed end), per meter strip of length of wall. The retaining wall consist of 300mm x 75mm wooden planks. 14. Calculate the maximum shear stress (MPa). A. 1.00 C. 0.66 B. 0.20 D. 0.33 15. Calculate the maximum bending stress (MPa). A. 42.67 C. 21.33 B. 25.60 D. 12.80

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REVIEW INNOVATIONS

SANTOS 2 - CE Board November 2021

16. If the allowable stresses are 10.5 MPa for bending and 0.8 MPa for shear, what should be the thickness (mm) of the plank to prevent failure. A. 75 C. 95 B. 85 D. 105

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