Test: Building Material & Construction - 1 - Civil Engineering (CE) MCQ

Plutonic rocks are the igneous rocks formed at considerable depths, generally between 7-10 km below the surface of the earth. Explanation: Because of a very slow rate of cooling at the depths, the rocks resulting from magma are coarse grained. 

Sedimentary rocks are formed through the gradual accumulation of sediments: for example, sand on a beach or mud on a river bed. As the sediments are buried they get compacted as more and more material is deposited on top.

Soundness of cement:

• The soundness of cement refers to the stability of the volume change in the process of setting and hardening. If the volume change is unstable after setting and hardening, the concrete structures will crack, which can affect the quality of buildings or even cause serious accidents, known as poor dimensional stability.

• Le-Chatelier method and autoclave method are used to find the soundness of the cement.

Limestone is a sedimentary rock composed principally of calcium carbonate (calcite) or the double carbonate of calcium and magnesium (dolomite). It is commonly composed of tiny fossils, shell fragments and other fossilized debris.

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite. Marble is typically not foliated, although there are exceptions. In geology, the term "marble" refers to metamorphosed limestone, but its use in stonemasonry more broadly encompasses unmetamorphosed limestone.

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite. Marble is typically not foliated, although there are exceptions. In geology, the term "marble" refers to metamorphosed limestone, but its use in stonemasonry more broadly encompasses unmetamorphosed limestone.Chemically, marble is known as calcareous rock.

Kaolin is a type of clay found in nature. It can also be made in a laboratory. 

As main constituent is clay so it is argillaceous rock as argillaceous means made up of clay, and kaolin is a clay.

Quartzite is a hard, non-foliated metamorphic rock which was originally pure quartz sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts.

Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. Some cool so quickly that they form an amorphous glass. These rocks include andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff.

Sandstone is a sedimentary rock composed of sand-size grains of mineral, rock, or organic material. It also contains a cementing material that binds the sand grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the sand grains.

Sedimentary rocks are formed from sediment that has been deposited by wind, water, or ice, and then compacted and cemented together. Limestone is a type of sedimentary rock that is formed from the accumulation of shells, bones, and other organic materials. It is often found in marine environments and is composed primarily of the mineral calcite, which is derived from the shells of marine organisms.

Stratified rock is a general term that refers to any type of rock that is formed in layers, such as sedimentary rocks, metamorphic rocks, and some types of igneous rocks. Limestone is a stratified rock because it is formed in layers from sediment that has been deposited over time.

Aqueous rock is a general term that refers to any type of rock that is formed through the action of water, such as sedimentary rocks. Limestone is an aqueous rock because it is formed from sediment that has been deposited by water.

Metamorphic rocks are formed through the transformation of existing rock under high pressures and temperatures. Limestone is not a metamorphic rock because it is not formed through the transformation of existing rock.

Pegmatite is an intrusive igneous rock with extremely large crystals sometimes greater than 10cm. Pegmatites are usually composed of feldspars, quartz and micas but may also contain minerals such as tourmaline (a silicate mineral that contains boron).

Laterite is a soil and rock type rich in iron and aluminium, and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by intensive and prolonged weathering of the underlying parent rock and hence called Arigillaceous rock as it contains clay sized particles.

Granite:

1. Granite is hard, coarse-grained rocks of crystalline structure.
2. It is a type of igneous rocks (plutonic rocks).
3. Granites can be predominantly white, pink, or grey in colour, depending on their mineralogy.
4. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals.
5. It contains 20% and 60% quartz by volume, and at least 35% of the total feldspar.

Formation of Gneiss

- Metamorphism of Sedimentary Rocks: Gneiss is primarily formed through the metamorphism of existing sedimentary rocks. This process involves intense heat and pressure acting on sedimentary rocks, causing them to recrystallize and reorganize their mineral composition, ultimately forming gneiss.

- Sedimentary Metamorphic Rocks: Gneiss can also be formed from other metamorphic rocks through further metamorphism. For example, schist, another metamorphic rock, can undergo additional heat and pressure to transform into gneiss.

- Mineral Composition: Gneiss typically consists of minerals such as quartz, feldspar, and mica, which are common in both sedimentary and metamorphic rocks. These minerals undergo changes in their crystal structure during the formation of gneiss.

- Distinctive Banding: One of the key characteristics of gneiss is its banded appearance, with alternating layers of light and dark minerals. This banding is a result of the intense pressure during metamorphism, which causes the minerals to align and segregate into distinct layers.

- Uses: Gneiss is valued for its durability, making it a popular choice for construction materials such as countertops and building facades. Its unique appearance and strength make it a versatile and attractive option for various applications.

Limestone: It is a sedimentary rock composed primarily of calcite, a calcium carbonate mineral with a chemical composition of CaCO₃.

Dolomite: It is a mineral composed of calcium and magnesium carbonate combined in equal molecular property, expressed by the formula CaMg(CO₃)_2.

Dolomite contains a 45% carbonate of magnesia.

White Statuary Marble is the most precious and sought-after marble in the World and it has always been prefered by the artists and especially sculptors for their masterpieces. 

Generally, white marble is found in Jabalpur district (M.P) & Black marble in Jaipur.

According to the chemical classification of rocks, they are classified as follows

1) Siliceous rocks:

The rocks which contain silica as the main constituent is called as siliceous rocks

Ex: Granite, Gneiss, Trap, Basalt, Sandstone, and Quartzite.

2) Argillaceous rocks:

The rocks which contain clay or alumina as a main constituent is called as argillaceous rocks.

Ex: Slate, Laterite, and Kaolin

3) Calcareous rocks:

The rocks which contain lime or calcium as the main constituent are called calcareous rocks.

Ex: Marble, Limestone, and Dolomite

Important point:

According to geological classification, rocks are classified as

1) Igneous rocks:

Ex: Granite, Basalt, Trap, and Dolerite

2) Sedimentary rocks:

Ex: Sandstone, Shale, Slate, Limestone, and Laterite

3) Metamorphic rocks:

Ex: Marble, Quartzite, Slate, and Schist

The earth's crust is made up of various types of rocks, differing from one another in texture, structure, colour, permeability, mode of occurrence, and degree of resistance to denudation.

Generally speaking, all rocks may be classified into three major groups:

• Igneous Rocks,
• Sedimentary Rocks,
• Metamorphic Rocks.

1. Igneous Rocks:

• Igneous rocks are formed by the cooling and solidification of molten rock (magma) from beneath the earth's crust.
• Example: Granite, Gabbro, Basalt, etc.

2. Sedimentary Rocks:

• Sedimentary rocks are formed by the process of weathering and cementation or precipitation on the Earth's surface. 
• Example: Sandstones, Kankar, shales, limestones, Mudstones, laterite, etc

3. Metamorphic Rocks:

• Formed when rocks are subjected to high heat, high-pressure changes inside the Earth.
• Example: Gneissoid, slate, schist, marble, quartzite, etc.

The softest crystal is the mineral talc, which has a hardness of one (1) on the Mohs Hardness Scale. Talc is a silicate (like many of the earth's most important minerals), and contains magnesium and a bit of water along with the silica and oxygen.

Correct Answer :- d

Explanation : Limestone(CaCO3) being the main compound it is liable to acid attacks, if MgCO₃ is the major constituent then it is more acid resistant. Its specific gravity is 2.72.

Correct Answer :- a

Explanation : The shingle is water bound pebble.

In civil engineering, Shingle is a thin piece of building material, usually with a butt end thicker than the other. Shingles are widely used as roof covering on residential buildings and sometimes for siding. They are of stock sizes and various materials—including wood, asphalt, and slate. They are attached in overlapping courses, or rows.

Slate can be made into roofing slates, which are installed by a Slater. And, are a type of roof shingle, or more specifically a type of roof tile. Slate has two lines of break ability "Cleavage and grain" which make it possible to split the stone into thin sheets. When broken, slate retains a natural appearance while remaining relatively flat and easy to stack.

In India, laterite soil is widespread, covering over 10% of the total geographical area, namely on the summits of the Western Ghats, Eastern Ghats (Rajamahal Hills, Vindhyas, Satpuras, and Malwa Plateau), southern parts of Maharashtra, parts of Karnataka, Andhra Pradesh, West Bengal Orissa, Jharkhand, Kerala, Assam, and Meghalaya.