ISRO Draughtsman Civil Mock Test - 6 - Civil Engineering (CE) MCQ

The clear cover should not exceed 75 mm in any case. According to IS 456 : 2000 nominal cover shall not be less than the diameter of the bar. The nominal cover is specified to meet durability requirements in Table 16 on page 47 of the IS Code.

HNO₃

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain

G= Specific gravity

e= void ratio

As per is 456:2000, clause 23.2.1, L/d foe spans upto 10 m.

Negative skin friction is phenomenon in which surrounding soil settles more than settlement of pile and this condition occurs when surrounding soil is very loose.

The SI unit of kinematic viscosity is square meters per second (m²/s).
Kinematic viscosity is a measure of a fluid's internal resistance to flow under gravitational forces. It is determined by measuring the time in seconds required for a fixed volume of fluid to flow a known distance by gravity through a capillary within a calibrated viscometer at a closely controlled temperature.
Hence, the correct option is (A).

For doubly reinforced section, tension reinforcement is designed for stress of 0.87fy but for compression reinforcement a lower stress must be used. The reason being that steel may buckle between shear stirrups under compressive stresses. And hence doubly reinforced beam is considered less economical because compressive steel is under stressed.

Hence the option A is correct.

Hence the option D is correct.

As per IS 456:2000, if the RCC structure is in the exposure of seawater spray, then the minimum grade of concrete to be used is M35, and if the structure is submerged or fully merged in seawater, then the minimum grade of concrete will be M40. If it expose in seawater, then the minimumgrade of reinforced concrete is M30

Hence the option D is correct.

The concrete mix that causes difficulty obtaining a smooth finish is known to possess hardness.

Hence the option C is correct.

(i) Oxides of Sulphur

(ii) Oxides of Carbon

(iii) Oxides of Nitrogen

(iv) Suspended particulate matter

Hence the correct answer is option C.

Hence the correct answer is option A.

Hence, the correct option is (b).

Mercury has the force of adhesion less than the force of cohesion and prefers to stick to itself rather than the glass surface. To achieve this, mercury takes a spherical shape to minimize its contact with the glass surface.

Hence, the correct option is (b).

radius of influence R = 300 m

thick b = 6m

radius r = 0.5 m

confined aquifer

k = 0.0345 m/sec

Hence the correct answer is option A.

Hence the correct answer is option C.

Hence the correct answer is option B.

Initial setting time shall not be less than 30 minutes and final setting time should not be more than 10 hours.

During prestressing, spalling stresses are generated in the region behind the loaded faces of anchor blocks. 

Spalling stress (bursting) occurs for the post-tensioned beam at the anchorage zone due to heavy bearing stress

At the zone between two anchorages, there is a volume of concrete surrounded by compressive stress. Forces are induced in the opposite direction to the applied forces and it forces the concrete out of the anchor block. On the other hand, the spalling stresses are set up owing to the strain compatibility relating to the effect of Poisson’s ratio. To prevent this, we use spalling reinforcement at locations of maximum bending moment

A systematic error always follows some definite mathematical or physical law and a correction can be determined and applied.

Such errors are of constant character and are regarded as positive or negative according to as they make the result too great or too small.

Blunders: A blunder (or gross error) is a significant, unpredictable mistake caused by human error that often leads to large discrepancies.

Blunders are typically the result of carelessness, miscommunication, fatigue, or poor judgment. Examples of common blunders are:

i) Improperly leveling of the surveying instrument.

ii) Setting up the instrument or target over the wrong control point.

Random (or accidental) errors are not directly related to the conditions or circumstances of the observation.

For a single measurement or a series of measurements, the error remains after all possible systematic errors and blunders have been eliminated.

Random errors are unpredictable and are often caused by factors beyond the control of the surveyor. Their occurrence, magnitude, and direction (positive or negative) cannot be predicted.

• Compaction improves the fluidity of concrete and with the reduction of internal friction, packing of coarse aggregates take place

• A well-compacted concrete is free of the loose pockets and air bubbles of entrapped air

• The main purpose of compaction of concrete is to get a dense mass without voids, to get the concrete to surround all reinforcement, and to fill all corners i.e. to provide intimate contact between the concrete and embedded materials