Q.1) The water absorption for good brick should not be more than –
A) 10% of its dry weight
B) 15% of its dry weight
C) 10% of its saturated weight
D) 15% of its saturated weight
The measure of the ability of a brick to absorb moisture from its surroundings is called water absorption of brick. Brick is a porous material, and its water absorption properties can affect its durability, strength, and resistance to weathering.
Q.2) Strength based classification of brick is made on the basis of :
A) IS : 3101
B) IS : 1077
C) IS : 3495
D) IS : 3496
Q.3) Hollow bricks are generally used with the purpose of :
A) Reducing the cost of construction
B) Providing insulation against heat
C) Increasing the bearing area
D) Ornamental look
Q.4) Refractory bricks are generally used to resist :
A) Chemical action
C) High temperature
D) Weathering action
Refractory bricks are special types of bricks that are made from materials that have high melting points and excellent heat resistance, such as alumina, silica, magnesia, and zirconia and are designed to withstand extremely high temperatures and harsh conditions without breaking down or degrading. Refractory bricks are made from materials that have high melting points and excellent heat resistance, such as alumina, silica, magnesia, and zirconia. They are used in a variety of industrial and commercial applications, including furnaces, kilns, incinerators, and other high-temperature processes.
There are many different types of refractory bricks, each with different properties and applications. Some common types include fire clay bricks, high alumina bricks, silica bricks, and magnesia bricks. The type of refractory brick used depends on the specific application and the temperature and conditions that it will be exposed to.
Q.5) Slate and Marble stone belong to –
A) Igneous Rocks
B) Metamorphic Rocks
C) Sedimentary Rocks
D) Foliated Rocks
Q.6) Which of the following possess more ability to resist fire ?
A) Compact sandstone
C) Red marble
Q.7) The age of trees can be understood by :
A) Measuring the diameter of pitch
B) The thickness of bark
C) Counting number of rings
D) Length of medullary rays
Q.8) What is the recommended moisture content of timber, which is used as a structural element for windows?
A) 5 – 10%
B) 10 – 16%
C) 16 – 26%
D) 26 – 36%
Q.9) The constituent of cement which is responsible for initial setting time of cement is –
A) Dicalcium silicate
B) Tricalcium silicate
C) Tricalcium aluminate
D) All of the above
Functions of different compound sin cement are :
Tricalcium silicate (C3S): This is the main compound in cement and is responsible for the strength and hardness of concrete.
Dicalcium silicate (C2S): It contributes to the strength and hardness of concrete, but not as much as C3S.
Tricalcium aluminate (C3A): It also helps to make the cement more workable, easier to mix and flash setting.
Tetracalcium aluminoferrite (C4AF): It also helps to regulate the setting time of cement and improves its resistance to sulfate attack.
Percentage of compunds by mass in cement :
C3S – 30 to 50%
C2S – 20 to 45%
C3A – 8 to 12%
C4AF – 6 to 10%
Q.10) Commonly used lime in white washing is :
A) Quick lime
B) Fat lime
C) Lean lime
D) Hydraulic lime
Q.11) Gypsum used in cement manufacturing acts as –
B) Air entraining agent
The role gypsum in cement is to slow down the setting time of cement thererby preventing the cement from setting too quickly and improves plasticity allowing it to properly mixed, place and finished.
Q.12) Which of the following type of lime is used for underwater constructions?
A) Fat lime
B) Quick lime
C) Slaked lime
D) Hydraulic lime
Similar to cement, hydraulic lime is a form of lime that may harden and set when exposed to water. The process of making it involves calcining (heating) limestone that contains a lot of clay or silica to a temperature that is lower than what is needed for complete conversion to quicklime. The end result is a hydraulic binder that is applied to building and renovation projects.
Q.13) Bulking of sand is caused due to :
A) Surface moisture
B) Air voids
D) Clay contents
Q.14) Which of the following compound affects the ultimate strength of cement?
A) Dicalcium silicate
B) Tetracalcium alumino-ferrite
C) Tricalcium aluminate
D) Tricalcium silicate
Q.15) For road pavements, the cement generally used is :
A) Ordinary Portland Cement
B) Rapid Hardening Cement
C) Low Heat Cement
D) Blast Furnace Slag Cement
Ordinary Portland Cement (OPC) : It is a type of hydraulic cement that is made from a combination of limestone, clay, and other materials. It is the cement type that is frequently used in building and is renowned for its toughness and durability. OPC is adaptable and has a wide range of applications, such as construction of buildings, roads, bridges, and other kinds of constructions.
Rapid Hardening Cement : It is a type of cement that is designed to achieve high strength in a short period of time. This type of cement is useful in situations where quick strength gain is required, such as in precast concrete, repair works, and emergency repairs.
Low Heat Cement : It is a type of cement that is designed to produce less heat during the hydration process, which can help to reduce the risk of thermal cracking. This type of cement is suitable for mass concrete pours, such as in dams, where the risk of thermal cracking is high.
Blast Furnace Slag Cement : It is a type of cement that is made by grinding together clinker and granulated blast furnace slag. Blast furnace slag is a by-product of the steel industry and is a highly reactive material that can be used to improve the strength and durability of concrete. This type of cement is known for its high compressive strength, low permeability, and resistance to sulfates and alkalis. It is often used in marine and coastal construction projects, as well as in the construction of dams and other large concrete structures.
Q.16) The hydraulicity of the hydraulic lime is mainly due to –
A) Calcium oxide
Q.17) Plastering is also called –
Q.18) The operation of removing humps and hollows of uniform concrete surface, is known as :
Q.19) Workability of concrete for a given water content is good if the aggregates are –
A) Angular aggregates
B) Flaky aggregates
C) Rounded aggregates
D) Irregular aggregates
Q.20) Green concrete may be made by adding :
A) Iron hydroxide
B) Barium Manganate
C) Iron oxide
D) Chromium oxide