BSc. Program in Architecture Building Materials and Construction-I PDF

BSc. Program in: Architecture Building Materials and Construction-I Chapter-1 Properties, composition, production and standards of construction Materials By: Misrak Z. 11/24/20...

BSc. Program in: Architecture Building Materials and Construction-I Chapter-1 Properties, composition, production and standards of construction Materials By: Misrak Z. 11/24/2024 1.6 Building Mortar 11/24/2024 INTRODUCTION  Building mortar is a paste made from a combination of sand, water, and a binding agent like cement or lime.  It's used to fill the spaces between building blocks, like bricks, stones, or concrete, to create a solid structure.  It is usually used in the following areas: In structural engineering, binds stone, brick, blocks together and fills the gaps in brick walls and the joints in large wall panels and various components; In decorative projects, used to plaster brick walls, floors, and structural beams and columns; and used to inlay natural stone, artificial stone, ceramic tiles and mosaic tiles. 11/24/2024 INTRODUCTION  According to different purposes, the building mortar can be classified into masonry mortar, surface mortar (ordinary surface mortar, waterproof mortar , decorative mortar), and special mortar (such as heat-insulated mortar , corrosion- resistant mortar, and sound-absorbing mortar). 11/24/2024 INTRODUCTION  Based on different cementing materials, building mortar can be divided into cement mortar, lime mortar, gypsum mortar, mixed mortar and polymer cement mortar.  The commonly used mixed mortar includes cement lime mortar, cement clay mortar and lime clay mortar. 11/24/2024 THE COMPOSITION OF MORTAR  To ensure the quality of building mortar, various materials in the composition of mortar should meet certain technical requirements. A. Cementing Materials  Proper cement varieties should be chosen according to the projects’ environmental conditions.  Lime , gypsum and clay can also be used as the cementing materials for mortar and they can be mixed with cement to prepare mixed mortar to save cement and improve the workability of mortar.  The strength grades of the cement used in cement mortar should not be more than 32.5; and that of the cement used in cement mix mortar should be no more than 42.5. 11/24/2024 THE COMPOSITION OF MORTAR B. Fine Aggregate  Sand is the fine aggregate for building mortar.  the maximum particle diameter of sand should be limited due to the thin layer of mortar.  For the sake of mortar quality, clean sand should be selected. C. Water  The Clean water without harmful impurities should be adopted to mix mortar. 11/24/2024 THE COMPOSITION OF MORTAR D. Mixtures and Additives  to improve the workability of mortar and save cement, some inorganic fine mixtures, such as lime paste, clay paste, and fly ash, can be added to mortar.  Lime should precipitate, and fly ash should be ground, for a better effect.  Sometimes, micro foam agent can be added to improve the workability of mortar.  Additives can be mixed in mortar to improve the workability and other construction properties of mortar.  The types, mixing amount, and physical properties of additives should11/24/2024 be determined by test. The Main Technical Properties of Mortar  For the sake of projects, the newly mixed mortar should have good workability, and the hardened mortar should have the required strength, the bending power to the bottom face, little deformation and durability. A. Workability of Fresh Mortar  Refers to the comprehensive properties of mortar easy for construction and good for quality, including mobility and water retention.  The mortar with good mobility is easy to be paved thinly and evenly on bricks and bonded with floors well. 11/24/2024 The Main Technical Properties of Mortar A. Workability of Fresh Mortar A.1. Mobility (Consistency)  The mobility of mortar is the property that mortar can flow under the role of dead weight and exterior force.  Fluidity is expressed by “sinking degree”, usually determined by the consistency of mortar. The bigger the sinking degree is, the better the mobility will be.  The selection of mortar mobility should be determined by masonry types, construction conditions, and weather. 11/24/2024 The Main Technical Properties of Mortar A. Workability of Fresh Mortar A.1. Mobility (Consistency) 11/24/2024 The Main Technical Properties of Mortar A. Workability of Fresh Mortar A.2. Water Retention  Refers to the property of mortar to maintain moisture.  When the mortar with good water retention is used in transportation, standing and pavement, water will not escape from mortar soon and the necessary consistency can be maintained.  To keep a certain amount of water in mortar is easy to manipulate and also guarantees the normal hydration of cement to maintain the strength of masonry. 11/24/2024 The Main Technical Properties of Mortar B. Strength and Strength Grades of Hardened Mortar  The hardened mortar should have big strength which is expressed by strength grade.  Compressive strength is the main basis for mortar strength.  The strength grade of mortar, expressed by ƒm, is determined by compressive strength average (MPa) measured through curing a group of six cube specimens with side length of 70.7mm for 28d, the standard test method.  The strength grades of mortar include: M20, M15, M10, M7.5, M5 and M2.5, the six grades.  The strength of mortar is connected with its surface material. 11/24/2024 The Main Technical Properties of Mortar B. Strength and Strength Grades of Hardened Mortar  For the ordinary cement mortar, the following equation can be used to calculate its compressive strength. B.1. Imhygrophanous Beds  The strength of the mortar used in Imhygrophanous beds (such as dense stone), similar as concrete, mainly depends on the cement strength and water-cement ratio , defined as follows:. 11/24/2024 The Main Technical Properties of Mortar B. Strength and Strength Grades of Hardened Mortar B.2. Hygrophanous Beds  Mortar is used in the hygrophanous beds (bricks and other porous materials), some of the water will be absorbed by base materials.  Because mortar has a certain property of water retention, no matter how much water is added, the remaining amount is the more or less the same.  the strength of mortar is determined by cement grade and dosage and has nothing to do with water -cement ratio, defined as follows: 11/24/2024 The Main Technical Properties of Mortar C. Adhesion Stress of Mortar  Brick and stone masonry is a solid entity composed of many blocks that are bonded by mortar as a whole.  Is required that mortar must have a certain adhesion stress over bricks and stones.  The more the compressive strength of mortar is, the bigger its adhesion stress will be.  its adhesion stress is related to the surface, cleanness, and humidity of bricks and stones, as well as the construction and curing conditions. For example, bricklaying needs watering, and the surface without clay will improve the adhesion stress and ensure the quality of masonry. 11/24/2024 The Main Technical Properties of Mortar D. Deformability of Mortar  It is easy for mortar to get deformed when it bears loads or the temperature changes.  If it deforms greatly or unevenly, the quality of masonry and surface will decrease and cause shrinkage and crack.  When more fine aggregates are used to mix the mortar, its deformation is bigger than the ordinary mortar.  In order to prevent the cracks caused by uneven shrinkage deformation, hemp cut, paper strip and others fabric materials can be mixed in the surface mortar. 11/24/2024 The Main Technical Properties of Mortar E. Durability of Hardened Mortar  The durability of mortar refers to the property to withstand wear and tear in the long-term use. E.1. Frost Resistance  The frost resistance of mortar refers to the property to resist freeze- thaw cycle.  Mortar is frozen and damaged because the water in its pores expands due to freeze and breaks the pores. dense mortar and the mortar with closed pores have good frost resistance.  The factors influencing the frost resistance of mortar also include cement types, strength grades, and water-cement ratio. 11/24/2024 The Main Technical Properties of Mortar E. Durability of Hardened Mortar E.2. Impermeability  The impermeability of mortar is property to resist the infiltration of pressure water.  It is mainly related to density and size and structure of the inner pores.  The connecting pores inside mortar and the cellular structures and pores formed when it is moulded, all of which can lead to water seepage of mortar. 11/24/2024 Other Kinds of Building Mortar A. Surface Mortar  Surface mortar is also called plaster mortar that is plastered on the surface of buildings in a thin layer to protect them, increase their durability, and also smooth their surfaces and make them clean and artistic.  Based on its different functions, surface mortar can be classified into ordinary surface mortar, waterproof mortar, decorative mortar and special surface mortar. 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.1. Insulating Mortar  Is made by mixing cement, lime, gypsum and other cementing materials with expanded perlite sand, expanded vermiculite, or ceramic particles and other lightweight porous materials together in a certain mix proportion.  Is lightweight and has good thermal insulation.  Its thermal conductivity is 0.07-0.10W/(m.K).  It can be used for the insulating layers of roofs and pipelines, insulating walls, and others. 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.1. Insulating Mortar 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.2. Sound-absorbing Mortar  Is consisted of lightweight porous aggregates. It has good sound absorption.  Can be made by mixing cement, gypsum, sand, and sawdust (whose volume rate is 6:1:3:5) together, or adding glass fibers, mineral wools into lime and gypsum mortar.  Can be used for the sound absorption of inner walls and roofs. 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.3. Corrosion-resistant Mortar  Is made by water glass (sodium silicate) and sodium fluo-silicate.  And sometimes, quartzite, granite, cast stone, and other kinds of fine aggregates can be added into it.  The hardened water glass has good corrosion resistance.  Mortar can be used for lining materials, corrosion-resistant floors, and the protective layers inside the corrosion-resistant containers. 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.4. Polymer Mortar  Is made by adding organic polymer emulsion into the cement mortar.  The common polymer emulsions include styrene butadiene rubber emulsion, chloroprene rubber emulsion and acrylic resin emulsion.  Has high bonding power, little shrinkage, low brittleness, good corrosion resistance, used for repair and protection engineering. 11/24/2024 Other Kinds of Building Mortar B. Special Mortar B.5. Radiation-proof Mortar  is made by mixing barite powder and barite sand into cement mortar.  Its mix proportion is: cement: barite powder: barite sand = 1:0.25: (4-5).  It can resist X-ray.  If borax and boric acid are mixed into the cement mortar, it will be the radiation-proof mortar which is often used in the radiation protective engineering. 11/24/2024 1.7 Reinforced Cement Concrete RCC  Reinforced Cement Concrete is the combination of concrete and steel bars (reinforcement bars).  Concrete is a highly versatile construction material, known for its strength in compression. However, it has limited tensile strength and is prone to cracking under tension. To enhance its tensile resistance, steel reinforcement is incorporated.  The addition of steel reinforcement transforms the concrete into reinforced cement concrete, where the structure can effectively bear both compressive and tensile forces.  This results in reinforced cement concrete structures that are exceptionally strong, durable, and capable of withstanding various loads and environmental conditions. 11/24/2024 RCC 11/24/2024 Properties Of Reinforced Cement Concrete Here are some of the finest properties of reinforced cement concrete:  Reinforced cement concrete is capable of withstanding compressive, bending and shear, and tensile forces.  It possesses adequate tensile and compressive strength.  It can resist fire and water  It provides complete insulation against sound and heat.  It makes the structure durable.  Reinforced cement concrete structures support any load.  Fresh reinforced cement concrete can moulded into desired shape and size.  It requires less skilled labour  The maintenance cost is low 11/24/2024  Composition Of Reinforced Cement Concrete Here are some of the finest properties of reinforced cement concrete:  The composition of reinforced cement concrete (RCC) involves the combination of cement, aggregates, water, and reinforcement bars or mesh. 1.Cement  Cement is a binding material that acts as a glue to hold the concrete mixture together.  Portland cement is commonly used in reinforced cement concrete. It reacts with water to form a paste that binds the aggregates and hardens over time. 11/24/2024  Composition Of Reinforced Cement Concrete 2. Aggregates  Aggregates are inert materials mixed with cement to form the bulk of the concrete. They provide stability, strength, and durability to the mixture. Aggregates are classified into two types: A. Coarse Aggregates  Coarse aggregates consist of crushed stone, gravel, or recycled concrete particles larger than 4.75 mm in size. They provide strength to the concrete and fill the voids between the reinforcement bars. 11/24/2024  Composition Of Reinforced Cement Concrete B. Fine Aggregates  Fine aggregates consist of sand or crushed stone dust particles smaller than 4.75 mm in size. They help to fill the voids between the coarse aggregates and improve the workability of the concrete. 11/24/2024  Composition Of Reinforced Cement Concrete 3. Water  Water is a crucial component in the concrete mixture. It reacts with cement during hydration, causing the mixture to harden and gain strength. The amount of water used should be carefully controlled to achieve the desired consistency and strength while ensuring proper hydration. 11/24/2024  Composition Of Reinforced Cement Concrete 4. Reinforcement Bars/Mesh  Reinforcement bars, commonly known as rebars, are made of high-strength steel. They are embedded within the concrete to enhance its tensile strength and resist cracking.  We can find information about the reinforcement steel bars using the bar bending schedule.  A bar bending schedule (BBS) is a detailed document or report that provides information about the reinforcement steel bars required for a particular construction project. It includes detailed specifications about the size, shape, length, and number of steel bars to be used in various structural components, such as beams, columns, slabs, and footings. 11/24/2024  Composition Of Reinforced Cement Concrete  Reinforcement mesh, made of interconnected steel wires, is also used in some applications. The size, spacing, and configuration of reinforcement bars or mesh depend on the design requirements and intended structural performance. 11/24/2024  Composition Of Reinforced Cement Concrete  The composition of reinforced cement concrete may also involve the use of additives or admixtures to modify the properties of the concrete.  Admixtures such as plasticizers, superplasticizers, air entrainers, and accelerators are often used to improve workability, durability, setting time, and other specific characteristics of the concrete mix. 11/24/2024  Types Of Reinforced Concrete 1. Reinforced Concrete with Steel Bars  One of the most common types of reinforced concrete is composed of steel bars, also known as rebar. These bars are strategically placed within the concrete to bear tensile forces and prevent cracking or structural failure.  The steel bars provide the necessary strength to withstand heavy loads and improve the overall durability of the structure. 11/24/2024  Types Of Reinforced Concrete 2. Fiber-Reinforced Concrete (FRC)  Fiber-reinforced concrete utilizes small, discrete fibers made of materials such as glass, steel, synthetic fibers, or natural fibers. These fibers act as reinforcement and enhance the concrete’s resistance to cracking and impact.  FRC is often preferred in applications that require increased toughness and durability, such as industrial flooring, tunnel linings, and earthquake-resistant 11/24/2024 structures.  Types Of Reinforced Concrete 3. Prestressed Concrete  Prestressed concrete is a type of reinforced concrete that undergoes a unique manufacturing process. Construction professionals place steel tendons or cables within the concrete and tension them before applying external loads.  This process compresses the concrete, effectively countering the tensile stresses that occur under load. The construction industry commonly uses prestressed concrete in bridges, high-rise buildings, and large infrastructure projects due to its high 11/24/2024 efficiency in spanning long distances.  Types Of Reinforced Concrete 4. Glass Fiber-Reinforced Concrete (GFRC)  Glass fiber-reinforced concrete is a composite material that combines concrete with fine glass fibers. GFRC exhibits excellent strength, durability, and aesthetic appeal, making it popular for architectural and decorative applications.  It allows molding into intricate shapes, enabling the creation of ornamental facades, decorative panels, and unique architectural elements. 11/24/2024  Types Of Reinforced Concrete 5. Reinforced Shotcrete  Shotcrete, also known as sprayed concrete, involves pneumatically projecting concrete onto a surface, making it a versatile construction method. Reinforced shotcrete involves the addition of reinforcement, typically steel fibers, to enhance its structural properties.  Various construction applications commonly employ this technique in tunnels, retaining walls, swimming pools, and repair work due to its flexibility, rapid application, and high 11/24/2024 strength. Applications Of Reinforced Cement Concrete  Various construction applications widely use reinforced cement concrete (RCC) due to its strength, durability, and versatility. Buildings and Structures  The construction industry extensively uses reinforced cement concrete in residential, commercial, and industrial buildings. It employs it for constructing beams, columns, slabs, walls, and foundations, providing structural stability and load-bearing capacity. Bridges and Flyovers  The construction industry primarily uses reinforced cement concrete as the material for constructing bridges and flyovers. It offers excellent strength and durability to withstand heavy loads, traffic 11/24/2024 vibrations, and environmental conditions. Applications Of Reinforced Cement Concrete  Dams and Reservoirs  Retaining Walls  Water Tanks and Swimming Pools  Tunnels and Underground Structures  Road Pavements  Precast Elements 11/24/2024 Factors To Consider Before Purchasing Reinforced Cement Concrete Strength Requirements  Determine the required strength of the concrete based on the design specifications and intended use of the structure. Consider factors such as load-bearing capacity, environmental conditions, and structural stability. Quality Standards  Moreover, ensure that the reinforced cement concrete meets the required quality standards and specifications. It is essential to check if the supplier or manufacturer has appropriate certifications and follows stringent quality control procedures. By doing so, construction professionals can ensure that the concrete meets the necessary strength, durability, and performance criteria, providing assurance of a reliable and high-quality construction 11/24/2024 material. Factors To Consider Before Purchasing Reinforced Cement Concrete Mix Design  Understand the concrete mix design, which includes the proportions of cement, aggregates, water, and additives. Verify if the mix design aligns with the project requirements and specifications. Consider factors such as workability, setting time, and desired strength. Source of Materials  Assess the source and quality of the constituent materials used in the reinforced cement concrete, including cement, aggregates, and reinforcement. Ensure that you obtain these materials from reputable sources and that they comply with relevant standards to maintain the overall quality of the concrete. 11/24/2024 Factors To Consider Before Purchasing Reinforced Cement Concrete Testing and Quality Assurance  Inquire about the testing and quality assurance procedures followed by the supplier or manufacturer. Ask for information about the testing methods used, such as compressive strength tests, slump tests, and reinforcement checks. This helps ensure the reliability and consistency of the reinforced cement concrete. Delivery and Transportation  Consider the logistics of transporting the reinforced cement concrete to the construction site. Evaluate the availability of transportation facilities, delivery timelines, and the supplier’s ability to deliver the required quantity on time. Efficient transportation helps maintain the workability and quality of the 11/24/2024 concrete. Factors To Consider Before Purchasing Reinforced Cement Concrete Cost and Budget  Furthermore, assess the cost of the reinforced cement concrete, including the price per unit volume or weight. It is important to compare quotes from different suppliers to determine the most cost-effective option without compromising on quality. Consider any additional costs such as transportation, testing, or special requirements. Environmental Considerations  Evaluate the environmental impact of the reinforced cement concrete production process. Inquire about the supplier’s sustainability practices, such as using recycled materials or employing eco-friendly manufacturing techniques. 11/24/2024 Factors To Consider Before Purchasing Reinforced Cement Concrete  Additionally, consider the carbon footprint and environmental certifications associated with reinforced cement concrete. By taking into account the environmental impact of the material and ensuring it meets relevant certifications, construction professionals can make sustainable choices that align with their environmental goals and contribute to greener construction industry. Technical Support and Expertise  Ensure that the supplier or manufacturer can provide technical support and guidance during the project. Verify their expertise in concrete technology, construction practices, and troubleshooting potential issues related to reinforced cement concrete. 11/24/2024 11/24/2024