Rehabilitation and Retrofitting of Structures Mid - II, April - 2015

1.On basis of width fine cracks have the size
  • < 1mm
  • 1-2mm
  • > 2mm
  • none
Answer: A
2.The process of deposition of water-soluble salts on the surface of masonry or concrete is called as
  • Spalling
  • efflorescene
  • crazing
  • laitance
Answer: B
3.For testing mass concrete in roads, air-field pavements and hydraulic structures, the approximate impact value required for rebound hammer
  • 10
  • 20
  • 30
  • 40
Answer: C
4.As per BIS the quality of concrete is termed as --------- for UPV of 3.0km/s-3.5km/s
  • Excellent
  • good
  • medium
  • poor
Answer: C
5.The NDT used for the determination of chloride concentration
  • Infrared thermography
  • rcpt
  • carbonation test
  • all
Answer: B
6.The method of deposition of concrete by jetting it with high velocity is called
  • Dry mixing concrete
  • shotcrete
  • motor replacement
  • grouting
Answer: B
7.The process of restoring or increasing section of an existing member by enclosing it in new concrete is called
  • Overlay
  • grouting
  • guniting
  • jacketing
Answer: D
8.The inheritability of concrete to heal cracks within itself is called
  • Carbonation
  • passivation
  • autogenous healing
  • none
Answer: C
9.Shotcrete is used in application of
  • Soil stabilization
  • water proofing
  • stabilization of rock slopes
  • none
Answer: C
10.The permeability of moist cured concrete in comparision to that of steam cured concrete is
  • Smaller
  • high
  • equal
  • none
Answer: A
11.The evaluation of cracks is necessary for ---------------
Answer: Identifying the cause of cracks
12.NDT using UPV method may be performed to determine presence of -------------
Answer: Internal cracks, voids
13.Crack width can be measured to an accuracy of about 0.025mm using ----------
Answer: Crack comparator
14.------------------ methods are commonly used in surface treatment process.
Answer: Grinding, scarifying, sand blasting
15.Oil, grease, animal fat may be removed by using -------------
Answer: Caustic soda
16.The function of polymer latex is to act as -----------------
Answer: Water reducing plasticizer
17.In dry packing, the repair material has a mortar proportion of ------------
Answer: 1:2.5 or 1:3
18.The epoxy resins are excellent binding agents with -----------
Answer: High tensile strength
19.The blow holes are caused by ----------
Answer: Improper design of form work
20.For repair of large and deep patches the method of repair used is ----------------
Answer: Concrete replacement