SSC-JUNIOR ENGINEER (Civil & Structural) Online Exam 2020 (Exam held on 23/03/2021) (Part-III)

GENERAL ENGINEERING CIVIL AND  STRUCTURAL

Total Questions: 50

11. According to IS 5968:1987, the minimum radius of curve to be provided in the alignment of unlined canals carrying a discharge of less than 30 cumecs up to 15 cumecs is:

Correct Answer: A. 600 m
Solution:No explanation given in the book

12. Two centrifugal pumps P and R are available for use in a pipe flow system and their head-discharge characteristics are as follows.

Pump PPump R
Discharge (cumecs)Head (m)Discharge (cumecs)

Head (m)

0.00400.0045
0.12350.1440
0.20280.2435
0.30180.3621

The following statements (S1, S2 and S3) pertain to the head and discharge values during actual operation. Neglect losses in the system. Which of the following statements are correct?

S1: When the two pumps P and R are connected in parallel, the discharge is 0.36 cumecs corresponding to a head of 35 m.

S2: When the two pumps P and R are connected in parallel, the discharge is 0.36 cumecs corresponding to a head of 70 m.

S3: When the two pumps P and R are connected in series, the discharge is 0.3 cumecs corresponding to a head of 46 m.

 

Correct Answer: D. S1 and S3
Solution:S1: When P and R are connected in parallel then, discharge for pump P at head (m=35) = 0.12 and discharge for pump R at head (m = 35) = 0.24
∴ Discharge =0.12+0.24= 0.36m³/sec
Corresponding to a load of 35 m.
S3: When P and R connected in series, then discharge is 0.3 cumec to a head 46 m.

13. Select the correct statement related to increasing the carbon content in steel from 0.2 to 0.9 per cent.

Correct Answer: D. Increasing the carbon content in steel increases the yield stress and reduces the ductility.
Solution:Generally, carbon is the most important commercial component of steel alloy. Increas-ing carbon content increases hardness and strength and improves hardenability. But carbon also increases brittleness and reduces weldability because of its tendency to form martensite. This means carbon content can be both a blessing and a curse when it comes to commercial steel.

And while there are steels that have up to 2 per cent carbon content, they are the exception. Most steel contains less than 0.35 per cent carbon. To put this in perspective, keep in mind that's 35/100 of 1 per cent.

14. Select the correct option with regard to the following two statements (S1, S2) pertaining to consolidation in soils.

S1: A soil is termed as normally consolidated, if the present effective over burden pressure is less than the maximum to which the soil was ever been subjected to in the past.

S2: The larger the value of co-efficient of consolidation, the shorter it takes for full consolidation to occur.

Correct Answer: C. S1 is false and S2 is true
Solution:

15. Which type of odour characteristic is NOT used for classifying odour of a given water sample as per IS 3025 (part-5) 1983?

Correct Answer: D. Degrees of turbidity
Solution:The types of odour present in waste water vary widely. The type of odour shall be ascribed by judging the degrees of sweetness, pungency, smokiness and rottenness of the odour. If the characteristic being judged is high in intensity, rate that characteristic as '100'; if medium, rate it as '50'; and if low, rate it as '0'. Although one can also use intermediate ratings but it is normally avoided. The odour class can be established by comparison with the perception levels of odour characteristics shown in Table.

16. The estimated value of a built-up property at the end of its useful life without being dismantled is called:

Correct Answer: C. salvage value
Solution:Salvage value is the value of the building at the end of the utility period without being dismantled. For example, A machine after the completion of it's usual span of life or when it becomes uneconomical to use, it may be sold and the same machine may be purchased by the other person for use for some other purpose. The price at which he purchased that machine is called as salvage value and which is called as sale value.

17. According to SP : 27-1984, the thickness of slab or RC slab shall be measured to the nearest of:

Correct Answer: C. 0.005 m
Solution:The thickness of the RCC slab shall be measured to the nearest 0.005 m and Dimension shall be measured to the nearest 0.01 m.

18. As per IS 800 : 2007, in the design of beams plate girders, when the web of a member acting alone is inadequate, different types of stiffeners are provided. Match the type of stiffeners provided in List I with the requirement to be satisfied by them in List II. (Use the Code in the lists for matching)

List–IList–II
(a) Intermediate transverse web stiffener(i) Provide local reinforcement to web under shear and bearing
(b) Load carrying stiffener(ii) Improve the buckling strength of a slender web due to shear
(c) Bearing stiffener(iii) Prevent local buckling of web due to concentrated loading
(d) Diagonal stiffener(iv) Prevent local crushing of web due to concentrated loading

 

(a)(b)(c)(d)
A.(ii)(iii)(iv)(i)
B.(iv)(iii)(i)(ii)
C.(iv)(iii)(ii)(i)
D.(iii)(ii)(iv)(i)
Correct Answer: A.
Solution:As per Cl.8.7.1.1 of IS 800:2007, when the web of a member acting alone (that is without stiffeners) proves inadequate, stiffeners for the following requirements should be provided:

(a) Intermediate transverse web stiffener: To improve the buckling strength of a slender web due to shear

(b) Load carrying stiffener: To prevent local buckling of the web due to concentrated loading.

(c) Bearing stiffener: To prevent local crush-ing of the web due to concentrated loading.

(d) Torsion stiffener: To provide torsional restraint to beams and girders at supports.

(e) Diagonal stiffener: To provide local reinforcement to a web under shear and bearing.

(f) Tension stiffener: To transmit tensile forces applied to a web through a flange.

19. Identify the property that changes as a function of the geometrical dimensions of a section in structural materials.

Correct Answer: C. Moment of inertia
Solution:The moment of inertia, or second area moment, or quadratic moment of area and also known as the second moment of area, is a geometrical property of an area which reflects how its points are distributed with regard to an arbitrary axis.

20. The maximum effective slenderness ratio for the compression flange of a steel beam against lateral torsional buckling as per IS 800-2007 is:

Correct Answer: B. 300
Solution:
MemberMax. effective slenderness ratio
A member carrying compressive loads resulting from dead loads and imposed loads.180
A tension member in which a reversal of direct stress occurs due to loads other than wind or seismic forces.180
A member subjected to compression forces resulting only from the combination with wind/earthquake actions, provided the deformation of such member does not adversely affect the stress in any part of the structure.250
Compression flange of a beam against lateral-torsional buckling.300
A member normally acting as a tie in a roof truss or a bracing system not considered effective when subject to a possible reversal of stress into compression resulting from the action of wind or earthquake forces.350
Members always under tension (other than pretensioned members).400