Cube Casting II Year

Stone masonry generally has good chemical resistance. Stone is a natural material that is typically resistant to most chemicals, including acids and alkalis. It is often used in construction for its durability and ability to withstand various environmental conditions. Stone masonry structures are known to have a long lifespan and can withstand exposure to chemicals without significant deterioration. Therefore, the correct answer is "good."

Brick masonry has a high fire resistance due to the properties of brick. Bricks are non-combustible and do not contribute to the spread of fire. They have a high melting point and can withstand high temperatures without deforming or losing their structural integrity. Additionally, the air pockets within the brick structure act as insulators, slowing down the transfer of heat through the wall. These factors make brick masonry highly resistant to fire, making the answer "high" correct.

When the particle thickness is less than 0.6 times the mean sieve size fraction to which the particle belongs, it is called "flaky". This means that the particle has a thin and flat shape, similar to a flake or a plate.

The mean size of the particle can be determined by taking the average of the sizes of the sieves that the particle passes through and retains on. In this case, the particle passes through a 20 mm sieve and retains on a 16 mm sieve. Therefore, the mean size of the particle is (20 mm + 16 mm) / 2 = 18 mm.

When the longest dimension of a particle is greater than 1.8 times the mean sieve size fraction to which the particle belongs, it is considered elongated. This means that the particle is significantly longer compared to the average size of particles in its fraction.

In Ashlar fine masonry, both the height of stones used is never less than their breadth and the length of stones is never less than twice their height. This means that the stones used in Ashlar fine masonry are always proportionate in terms of their dimensions. This ensures stability and structural integrity in the construction.

The correct answer is 25mm because chamfering stones refers to the process of cutting or grinding the edges of the stone to create a beveled or angled edge. In this case, the stones are chamfered to a width of 25mm, meaning that the edges are cut or ground at an angle to create a 25mm wide beveled edge.

Stone masonry is known for its excellent strength compared to brick masonry. Both options (a) and (b) are correct as stone masonry is not only excellent in strength but also has a higher strength than brick masonry. Therefore, the correct answer is both (a) and (b).

Stone masonry has a high resistance to dampness. This is because stones are naturally porous and have low water absorption properties. Additionally, stone masonry structures are typically built with proper joints and mortar, which further enhances their resistance to dampness. The high resistance to dampness makes stone masonry a durable and long-lasting construction material, as it helps prevent water damage and the growth of mold and mildew.

Brick masonry has a poor chemical resistance. This means that it is not capable of withstanding or resisting the damaging effects of chemicals. It may deteriorate or get damaged when exposed to various chemicals, such as acids or alkalis. Therefore, it is not considered a suitable material for applications where it will come into contact with chemicals.

Stone masonry has a moderate fire resistance. While stone is a non-combustible material, the mortar used in stone masonry can be affected by fire. The mortar may crack or crumble under high temperatures, compromising the integrity of the structure. However, compared to other building materials like wood or concrete, stone masonry is generally more resistant to fire. It can withstand heat for a longer duration before showing signs of damage. Therefore, the fire resistance of stone masonry is considered moderate.

If the mean size of a particle is 18 mm, and the particle is flaky, it means that the particle has a larger length and width compared to its thickness. Therefore, the thickness of the flaky particle would be less than 10.8 mm.

In Ashlar chamfered masonry, the stones are chamfered on the exposed face at 450. This means that a beveled edge is created on the face of the stone at a 45-degree angle. Chamfering is done to add a decorative touch to the masonry work and to prevent sharp edges. The measurement of 450 indicates the angle at which the chamfer is created, ensuring a consistent and aesthetically pleasing appearance.

Ashlar facing masonry refers to a type of construction where there is an Ashlar facing, which can be either made of rubble masonry or brick masonry, and a backing. The backing can also be made of either rubble masonry or brick masonry. Therefore, the correct answer is either (a) or (b), as both options are possible in Ashlar facing masonry.

If the mean size of a particle is 18 mm, it means that the average size of the particles is 18 mm. An elongated particle would have a longer dimension than the average size, so it would be more than 18 mm. Since the longest dimension of the elongated particle is asked, the answer would be more than 32.4 mm, as 32.4 mm is less than the average size of 18 mm.