Correct Answer: A. Resistance to dynamic loading
Solution:
Coir, derived from coconut husks, is known for its natural elasticity, being lightweight (ease to carry), and durability (long service span), especially its resistance to rot and moisture. However, it is a relatively soft and flexible fibre, and while it can absorb some impact, it is not primarily characterized by high resistance to heavy or sudden dynamic loads compared to more rigid flooring materials.
Correct Answer: D. partition walls
Solution:
Aerated Autoclaved Concrete (AAC) blocks have lower compressive strength compared to traditional concrete blocks, making them unsuitable for load-bearing structures like foundations or shear walls. Their primary advantage is their light weight, which makes them ideal for non-load-bearing partition walls, reducing the overall dead load on the structure.
Correct Answer: B. 38 mm thick cement concrete 1 : 2 : 4 laid over 11.5 cm thick cement concrete 1 : 5 : 10
Solution:
The Central Building Research Institute (CBRI) provides specifications for cost-effective and durable construction. For single and double-story residential buildings, a common specification for the ground floor involves a base layer of lean concrete (1:5:10) followed by a wearing course of a richer concrete mix. The standard specification is a 38 mm thick top layer of 1:2:4 cement concrete.
Correct Answer: D. Oxalic acid
Solution:
Oxalic acid is a mild acid that is used in a powdered form, mixed with water to create a paste. When rubbed on mosaic or marble floors with a polishing machine, it reacts with the calcium carbonate in the stone to create a hard, glossy, and durable finish. Other acids are too harsh and can damage the floor.
Correct Answer: B. 20-30 mm
Solution:
Asphalt flooring, often applied in layers, typically has a total thickness ranging from 20 to 30 mm to provide a durable and resilient surface for residential and commercial applications.
Correct Answer: B. Ground, upper
Solution:
By definition, the floor built on the ground level is called the ground floor, and any subsequent floors in a multi-storey building are referred to as upper floors.
Correct Answer: A. Grano flooring
Solution:
While often associated with mosaic flooring due to the use of chips, terrazzo is sometimes referred to as granolithic flooring (or grano), particularly when granite chips are used, due to the similar construction process of using aggregates in a concrete matrix.
Correct Answer: D. Upper floor
Solution:
Any floor constructed above the ground level in a building is termed an upper floor, distinguishing it from the ground floor which rests directly on the earth.
Correct Answer: B. 2.2 m
Solution:
Building codes, such as the National Building Code (NBC) of India, typically specify a minimum clear height of 2.2 meters for habitable spaces, including mezzanine floors, to ensure adequate headroom and safety.
Correct Answer: A. Rib floor
Solution:
A ribbed floor consists of beams (ribs) with slabs spanning between them. The spaces between the ribs provide a convenient and concealed pathway for running plumbing pipes and electrical conduits without altering the visual appearance of the ceiling.
Correct Answer: C. Mosaic floor
Solution:
The construction of traditional mosaic floors involves laying a concrete base, followed by a bedding layer of lime-surkhi mortar (5 to 8 cm thick) into which the mosaic tiles or chips are set to create the decorative surface.
Correct Answer: A. Precast concrete floor
Solution:
Precast concrete floor units are manufactured off-site and then transported and lifted into place. Since they are already cured and solid, they do not require the on-site shuttering or formwork that is necessary for cast-in-situ concrete floors.
Correct Answer: B. 1 : 1
Solution:
For fixing floor tiles, a rich cement mortar mix of 1:1 (1 part cement to 1 part sand) is often used to ensure strong adhesion and a durable bond between the tile and the base course.
Correct Answer: D. suspended floors
Solution:
Suspended floors are floors that are not in direct contact with the ground. They are supported by walls, beams, or columns, creating a void underneath. All upper floors are examples of suspended floors.
Correct Answer: A. Cork flooring
Solution:
Cork has excellent sound-absorbing properties due to its cellular structure. This makes it an ideal choice for environments where noise reduction is important, such as libraries, churches, and theatres.