Construction Technology 1 - Material Science BSTC-411 Review Questions

Physical properties of materials are the measurable attributes that describe how a substance behaves or responds to external conditions without changing its composition. Examples include density, color, hardness, and conductivity.

Mechanical properties of materials refer to their behavior under the influence of applied forces or loads. These properties include attributes such as strength, elasticity, ductility, hardness, and toughness.

Chemical properties of materials involve their reactivity and how they change composition when exposed to other substances or conditions. These properties include flammability, corrosion resistance, and chemical stability.

<p>The fire resistance of materials refers to their ability to withstand the effects of fire until they begin to disintegrate. In the case of cement materials, fire resistance is related to the ability to withstand the effects of fire until the cement materials begin to disintegrate, which typically starts at a temperature of approximately 500 degrees.</p> Signup and view all the answers

<p>The main raw materials for cement manufacturing are calcium, silica, alumina, and iron.</p> Signup and view all the answers

<p>The concept of fire resistance of materials refers to their ability to withstand the effects of fire until they begin to disintegrate. In the case of cement materials, when exposed to fire, the water in the concrete evaporates, weakening the cement and reducing the strength of the concrete. This process begins approximately at a temperature of 500 degrees Celsius.</p> Signup and view all the answers

<p>The three main categories of properties of materials are physical, mechanical, and chemical properties. Examples of physical properties include density, color, hardness, and conductivity. Mechanical properties include strength, elasticity, ductility, hardness, and toughness. Chemical properties involve reactivity and changes in composition when exposed to other substances or conditions, such as flammability, corrosion resistance, and chemical stability.</p> Signup and view all the answers

<p>The four main raw materials used in cement manufacturing are: 1. Calcium, which is obtained from limestone and chalk. 2. Silica, sourced from clay, sand, and shale. 3. Alumina, derived from bauxite, clay, and aluminum ore. 4. Iron, obtained from iron ore, bauxite, and recycled materials. These materials are combined and heated to form the clinker, which is then ground into cement.</p> Signup and view all the answers

<p>The chemical properties of materials involve their reactivity and how they change composition when exposed to other substances or conditions. Examples of chemical properties include flammability, corrosion resistance, and chemical stability. For instance, materials with high flammability are prone to catching fire and burning, while those with good corrosion resistance can withstand the effects of corrosion from chemical reactions.</p> Signup and view all the answers

<p>When concrete is exposed to fire, the water in the concrete evaporates, and the cement begins to dry. This weakens the cement and reduces the strength of the concrete. The disintegration of cement materials under high temperatures leads to a decrease in the structural integrity and load-bearing capacity of the concrete.</p> Signup and view all the answers