Structure and Properties of Construction Materials CES 251 Fall 2024 PDF

AIN SHAMS UNIVERSITY FACULTY OF ENGINEERING STRUCTURE AND PROPERTIES OF CONSTRUCTION MATERIALS CES 251 DR. MAHMOUD GALAL ASSISTANT PROFESSOR – STRUCTURAL ENGINEERING DEPARTMENT FACULTY OF ENGINEERING - AIN SHAMS UNIVERSITY...

AIN SHAMS UNIVERSITY FACULTY OF ENGINEERING STRUCTURE AND PROPERTIES OF CONSTRUCTION MATERIALS CES 251 DR. MAHMOUD GALAL ASSISTANT PROFESSOR – STRUCTURAL ENGINEERING DEPARTMENT FACULTY OF ENGINEERING - AIN SHAMS UNIVERSITY FALL 2024  OUTLINES  INTRODUCTION  BASIC PROPERTIES  BUILDING UNITS (ROCKS – BRICKS)  TIMBER  INSULATION (WATER PROOFING – THERMAL – ACOUSTIC)  STEEL (TENSION – COMPRESSION – FLEXURE – SHEAR)  INTRODUCTION  Types of Structures Concrete Structures Steel Structures Masonry Structures Wooden Structures  INTRODUCTION  Concrete Structures  Advantages Availability of concrete ingredients (Cement – Aggregates – Water) Lower cost than other systems Manufacturing in various shapes Reliable compressive strength Can be used for water structures Lower maintenance precautions  INTRODUCTION  Concrete Structures  Disadvantages Cracking susceptibility (Drying shrinkage - Overloading) Lower tensile strength Lower specific strength (Strength / Weight) Creep behavior Reinforcing steel corrosion  INTRODUCTION  Steel Structures  Advantages Higher specific strength Fast and easy erection Ease of replacing defected members Ductile failure No need to formwork  INTRODUCTION  Steel Structures  Disadvantages Higher cost than concrete structures Sensitive to fire Sensitive to corrosion Need high qualified labor Higher maintenance precautions  INTRODUCTION  Masonry Structures  Advantages Save formwork Save reinforcing steel Fast construction Save plastering  INTRODUCTION  Masonry Structures  Disadvantages Difficult modifications Limited floors Sensitive to earthquakes  INTRODUCTION  Wooden Structures  Advantages Simplicity of construction Fast construction Excellent thermal insulation Light weight  INTRODUCTION  Wooden Structures  Disadvantages Higher cost than other systems Sensitive to fire Sensitive to water Limited floors Environmental impacts THANK YOU  BASIC PROPERTIES Engineering project requires : Material – Method – Men – Money (4 M,s) Basic requirements for Material Selection : o Performance o Safety o Economy Economy depends on : o Availability and cost of raw materials o Construction cost (manufacturing – transportation – placing) o Maintenance It is necessary for an engineer to be conversant with the properties of engineering materials. Right selection of materials can be made for a construction activity only when material properties are fully understood.  BASIC PROPERTIES Types of Engineering Materials Metallic Non-Metallic Energy Generating Materials Materials Materials Ferrous Non-Ferrous Heavy metals Light metals Steel Copper Aluminum Cast Iron Nickel Magnesium Soft metals Lead Tin  BASIC PROPERTIES Types of Engineering Materials (cont.) Metallic Non-Metallic Energy Generating Materials Materials Materials Construction Supplementary Petroleum Materials Construction Uranium Materials Building Stones Bricks Ceramics Gypsum Plastics Cement Rubber Concrete Paints Timber Insulation Materials  BASIC PROPERTIES Properties of Engineering Materials I. Physical II. Chemical III. Mechanical (The most important) IV. Thermal  BASIC PROPERTIES I. Physical Properties: Properties those describe the shape and the general condition of the material like : 1) Shape, Texture & Dimensions 2) Density 3) Unit Weight 4) Volumetric (Bulk) Weight 5) Specific gravity 6) Void ratio 7) Absorption 8) Permeability  BASIC PROPERTIES 1- Shape, Texture & Dimensions Stone units Gravel Sand Wooden Logs Raw Blocks of Stone Corrugated Sheets Bricks or Masonry Units  BASIC PROPERTIES 2- Density (ρ) It is the ratio between mass (M) and volume without voids (Vs) ρ = M/Vs 3- Unit Weight () It is the ratio between weight (W) and volume without voids (Vs)  = W/Vs 4- Volumetric Weight (o) It is the ratio between weight (W) and volume including voids (VT) o = W/VT  BASIC PROPERTIES 5- Specific Gravity (S.G.) It is the ratio between material unit weight (m) and unit weight of water (w) S.G. = m / w 6- Porosity It is the ratio between volume of voids (Vv) d total volume of matter (VT) Vv S.G   w   o Porosity    n   Vt S.G   w Vv S.G   w   o Void Content %   100   100 Vt S.G   w Different grain sizes and packing arrangements result in different porosity values. Individual pore spaces decrease in size with decreasing grain size. Porosity varies with packing (arrangement) of grains.  BASIC PROPERTIES 7- Water Absorption The ability of the material to absorb water and to keep it in its voids Percentage of Natural Absorption (% N. A.) It is the ratio between weight of absorbed water (Ww) and dry weight of matter (Wd) Percentage of Full Absorption (% F. A.) It is the ratio between weight of absorbed boiled water (Ww) and dry weight of matter (Wd) Coefficient of Saturation It is the ratio between % N. A. and % F. A.  BASIC PROPERTIES 8- Water Permeability The ability of the material to permeate water through it. It can be measured by the Coefficient of Permeability. Coeff. of Permeability = The amount of water that permeate through the material across the unit area under a Specified pressure in a Specified time  BASIC PROPERTIES II. Chemical Properties: o Chemical composition o Ph Value (Acidic , Alkaline, Neutral) o Chemical resistance (Weight loss , Strength loss , …….) o Durability: can be defined as its resistance to deterioration resulting from external and internal causes. (Weight loss , Strength loss , Resistance to corrosion, …….) with time.  BASIC PROPERTIES III. Mechanical Properties: They are the properties that describe the behavior of materials subjected to different types of loads (static, dynamic or repeated loads). Types of Loading Static Loading Dynamic Loading Repeated Loading A force applied A force applied A force applied repeatedly, slowly to an rapidly which causing causing variation in the assembly or object an impact magnitude of the internal (in long time) (in short time) forces.  BASIC PROPERTIES  Definitions  Strain (ɛ) Is a dimensionless value, it is the ratio between the change of length to the original length. Li  L L   L0 L0  Stress (F) Is the intensity of internal forces = Force/Area Stress units = Force unites / Area Units = N/mm2 (MPa), kg/cm2  BASIC PROPERTIES  Definitions  Normal Stress Is the stress normal to the section, and could be tension or compression stress. P F A Where: F Normal stress P Applied load (force) A Cross sectional area  BASIC PROPERTIES  Definitions  Strength It is (tensile, compressive, flexural, shear), the ability of material to resist static loads. It is measured by stress (load/unit area) a) Tensile strength P max f tension = A0 b) Compressive strength P max f comp.= A0  BASIC PROPERTIES  Definitions  Elasticity The ability of the material to return back to its original shape and dimensions after removing the applied load ‫ﻣﻧطﻘﺔ اﻟﻣروﻧﺔ‬  Plasticity Presence of permanent deformations after removing the applied load  BASIC PROPERTIES  Definitions  Stiffness Resistance to deformations (measured by the Young,s Modulus “E”  BASIC PROPERTIES  Definitions  Poisson’s Ratio The ratio between lateral strain “εL” to the axial strain “εa” υ = - (εL / εa) Since the axial and lateral strains will always have different signs, The negative sign in the equation makes the ratio positive. Theoretically for all Isotropic – Homogenous materials, Poisson’s ratio has a value between 0.0 and 0.5 For brittle materials (stones, concrete, bricks) υ = 0.1 to 0.20 For ductile steel υ = 0.3  BASIC PROPERTIES  Definitions  Ductility The maximum percentage of deformation. Ductile materials : materials have large deformation %. (% Elongation & % Reduction in area in Tension test of steel)  Brittleness Failure of materials almost without deformations. (Concrete – Bricks – Stones - ……..most of building materials)  Hardness Material Surface Resistance to any indentation or scratch caused by any type of load (Property for the material surface)  BASIC PROPERTIES  Definitions  Resilience The ability of the material to absorb energy because of the applied load and return it back completely after removing the load “Elastic strength of dynamic load”  Toughness The maximum energy can be absorbed by the material up to failure “Ultimate strength of dynamic load”  BASIC PROPERTIES IV. Thermal Properties: 1) Coefficient of thermal conductivity (effect of voids) 2) Fire Resistance (voids – volumetric weight) 3) Thermal Expansion (expansion joints)  BASIC PROPERTIES Standard Specifications The Standard specification is an explicit set of requirements to be satisfied by a material, product, or service. The specifications those done and presented by the specialists in every branch and issued by organizations such as : ESS, BSS ,ASTM, DIN ,ISO In Egypt the “Egyptian Organization for Standards and Quality” “‫”اﻟﮫﯿﺌﺔ اﻟﻤﺼﺮﻳﺔ اﻟﻌﺎﻣﺔ ﻟﻠﻤﻮاﺻﻔﺎت واﻟﺠﻮدة‬ is responsible for the issue of the ESS 4756-1 / 2007 “Cement” ‫م ق م‬ Standard specifications are updated continuously every several years according to new updates in the field of materials technology.  BASIC PROPERTIES Codes of Practice “Codes of practice represent the basic fundamentals for design and Construction of any project to ensure its overall safety.” Usually codes of practice gives the minimum requirements for Material properties - Design – Construction – Quality control - …. Codes of practice are updated continuously every several years Based on the conclusions and recommendations of the scientific research. For example : “The Egyptian code of practice for design and construction of reinforced concrete” ECP 203-2007 “The current code” ECP 203-2020  BASIC PROPERTIES Factor of Safety Factor of Safety = (Ultimate strength / Working stress) ≥ 1 Value of Safety factor depends on : 1. Variability of material properties (Concrete, Steel, Bricks, …..) Mean – Standard Deviation – Coeff. of Variation 2. Accuracy of the applied loads (DL, LL, Wind, Earthquakes, Temperature, Differential settlement, Unexpected loading,….) 3. Importance of the structure  BASIC PROPERTIES Variability of Results Mean Standard Deviation (SD) n n  2   X _  X i   X i  X  i 1  SD  i 1 n 1 n Coefficient of Variation “V” V = Less than 5% ---- Excellent V = 5% to 10% ------ Good V = (SD / Mean) x100 V = 10% to 15% ----- Fair V More than 15% --- Poor THANK YOU  BUILDING UNITS  Main Types Building units are classified to two main types  Building Units From Stones  Building Units From Bricks  BUILDING UNITS  Applications  Building Units From Stones o Construction Purposes Wall bearing Columns Retaining walls Domes and piers Partitions  BUILDING UNITS  Applications  Building Units From Stones o Decoration Purposes Covering of walls and facades  BUILDING UNITS  Applications  Building Units From Stones o Irrigation Works Dams Tanks Slope stability  BUILDING UNITS  Building Units From Stones  Applications o Manufacturing of construction materials Aggregates  BUILDING UNITS  Concretion Using Saws Regular shapes Using Wedges Semi-regular shapes  BUILDING UNITS  Concretion Using Crushers Irregular shapes Using Explosion Irregular shapes  BUILDING UNITS  Finishing  BUILDING UNITS  Geological classification Igneous Rocks Gradual Cooling (Granit): Regular structural arrangement, and High specific gravity Sudden Cooling(Basalt): Good surface hardness, and hard in operation  BUILDING UNITS  Geological classification Sedimentary Rocks Lime stone - Easy to use - Aggregate – cement – Wall bearing  BUILDING UNITS  Geological classification Metamorphic Rocks Marble - Architectural works - High abrasion resistance  BUILDING UNITS  Building Units From Bricks  Application o Construction Purposes Wall bearing Retaining walls Partitions  BUILDING UNITS  Building Units From Bricks  Application o Architectural Purposes Facades Glass walls Tubs  BUILDING UNITS  Building Units From Bricks  Classification (In terms of shape) o Solid bricks Void Ratio < 15 % of Total o Perforated bricks Void Ratio > 15 % of Total Volume Holes Diameter < 20 mm o Hollow blocks Void Ratio > 15 % of Total Volume Holes Diameter > 20 mm  BUILDING UNITS  Building Units From Bricks  Classification (In terms of type) o Clay or shale bricks o Concrete bricks or blocks o Sand lime bricks o Gypsum blocks o Glass bricks o Isolated bricks  BUILDING UNITS  Building Units From Bricks  Properties of Bricks  BUILDING UNITS  Building Units From Bricks  Properties of Bricks  BUILDING UNITS  Building Units From Bricks  Efflorescence o Nil Efflorescence: When there is not perceptible deposit of efflorescence. o Slight Efflorescence: Not more than 10 % area of the brick covered with a. thin deposit of salt. o Moderate Efflorescence: Covering up to 50 % area of the brick. o Heavy Efflorescence: Covering 50 % or more but unaccompanied by. powdering or flacking of the brick surface. o Serious Efflorescence: When, there is a heavy deposit of salts accompanied. by powdering and/or flacking of the exposed surfaces.  BUILDING UNITS  Building Units From Bricks  Selection of Brick Units o Wall bearing : Good compressive strength o External façades at industrial areas : Chemical stability o Desert areas : Min coefficient of thermal expansion, low heat conductivity o Stairs and pavements : High abrasion resistance  Factors Affecting the Strength on Masonry or Stone Wall Type of unit Strength of unit Type of mortar Method of construction THANK YOU  TIMBER Wood is a natural, renewable product from trees. Trees are classified as either endogenous or exogenous based on the type of growth. Endogenous: grows with intertwined fibers such as bamboo – not for structural applications. Exogenous: grows from the center out by adding concentric layers of wood around the central core – classified to soft wood or hard wood. softwoods are softer, less dense, and easier to cut than hardwoods.  TIMBER Structure of Wood  TIMBER  Types 1. Bamboo ‫اﻟﺧﯾزران‬ 2. Cidar ‫اﻻرز‬ 3. Cherry ‫اﻟﻛرز‬ 4. Mahogany‫اﻟﻣﺎھوﺟﻧﻲ‬ 5. Pine ‫اﻟﺻﻧوﺑر‬ 6. Plywood ‫اﻟﻛوﻧﺗر‬  TIMBER  Defects  Defects Due to Natural Forces  Knots:  Shakes  Wane  TIMBER  Defects  Defects Due to Attack by Insects insects like beetles or marine boars eat wood, make holes and weaken the strength of the wood.  Defects Due to Fungi Stain: When fungi feed only on sapwood. Decay: When fungi feed only on sapwood and heartwood.  Defects Due to Defective Seasoning Faulty method of seasoning causes serious defects in woods. During seasoning of timber, exterior or surface layer of the timber dries before the interior surface. So, stress is developed due to the difference in shrinkage. Some of the defects resulting from defective seasoning are as follows:-  TIMBER  Defects  Defects Due to Defective Seasoning  Bow: Curvature formed in direction of the length of the timber is called bow.  Cup: Curvature formed in the transverse direction of the timber is called a cup.  TIMBER  Defects  Defects Due to Defective Seasoning  Check: Check is a kind of crack that separates fibers, but it doesn’t extend from one end to another.  Split: Split is a special type of check that extends from one end to another.  TIMBER  Defects  Defects Due to Defective Seasoning  Honey Combing: Stress is developed in the heartwood during the drying process or seasoning. For these stresses, cracks are created in the form of honeycomb texture.  TIMBER  Seasoning Green wood, in living trees, contains from 30% to 200% moisture by the oven-dry weight. Seasoning removes the excess moisture from wood. For structural wood, the recommended moisture content varies from 7% to 14%. Wood is seasoned by air and kiln drying. Air drying is inexpensive, but slow. Drying temperatures in a kiln range from 20°C to 50°C, typically requiring 4 to 10 days. Seasoning of timber is done to improve the properties of wood and fulfill some specific requirement.  TIMBER  Water Content Moisture exists in wood as either bound or free water. Bound water is held within the cell wall by adsorption forces, whereas free water exists in the cell cavities. In green wood, The level of saturation at which the cell walls are completely saturated, but no free water exists in the cell cavities, is called the fiber saturation point (FSP). Typically in the range of 21% to 32%. Removal of moisture below the FSP has a large effect on physical and mechanical properties of wood, whereas above the FSP, the properties are independent of moisture content.  TIMBER  Water Content The moisture content for the average atmospheric conditions is the equilibrium moisture content (EMC). The EMC ranges from less than 1% to over 20%.  TIMBER  Properties Specific gravity: Specific gravity of wood depends on cell size, cell wall thickness, and number and types of cells. Density: The dry density of wood ranges from 160 kg/m3 to 1000 kg/m3. Thermal Conductivity: Thermal conductivity is a measure of the rate at which heat flows through a material. It ranges from 0.06 W/(m.K) [to 0.17 W/(m.K)].  TIMBER  Properties Compressive Strength: Parallel to fibers, perpendicular to fibers. Tensile Strength: Parallel to fibers, perpendicular to fibers. Modulus of elasticity : The modulus of elasticity of wood is the slope of the linear portion of the stress– strain curve. THANK YOU  INSULATION  Main Types Water Proofing Insulation All buildings need insulation from moisture, rain, groundwater and surface water because the moisture helps to damage the elements of construction. Thermal Insulation Buildings are thermally insulated to prevent or reduce various forms of heat transfer. Insulator resists from out to in or in opposite direction. Acoustic Insulation Acoustic insulation is to prevent the permeability of sound and absorb it or to disperse it to reduce noise.  INSULATION  Water Proofing Insulation Causes of Dampness 1. Rain water: The rainwater has the ability to penetrate the roof of the building, especially for poor surfaces. 2. Surface water: This means river or sea close to building causing moisture seeps to the foundations. 3. Underground water: It could be transmitted through the pores of the soil by the capillary action and ascend to the foundations. 4. Poor sewage drainage causes damage exposed areas such as foundation or bath areas.  INSULATION  Water Proofing Insulation Causes of Dampness  INSULATION  Water Proofing Insulation Effect of Dampness Damage of building materials and elements of the house. Efflorescence of the walls, floor and ceiling. Damaging the paint. The failure in the timber used. Corrosion of metallic parts.  INSULATION  Water Proofing Insulation Main Types 1. Bitumen: Bitumen is very common in waterproofing insulation because of its cheapness compared to the other insulating materials in addition to its flexibility and resistance to the proliferation of fungi and insects. Liquid of bitumen which is used to fill the cracks in the concrete or roof tiles. It could be used as paint for the foundations and walls that are in a direct contact with the soil. Solid of bitumen (asphalt) which is used for paving of the street after mixing with sand and stones.  INSULATION  Water Proofing Insulation Main Types Bitumen rolls: These layers have the excellent insulating and waterproofing capability. The bitumen layer commonly used to insulate the ceiling or walls and it is available in (3, 4 and 5 mm) thickness. Asphalt Bitumen paint Bitumen rolls  INSULATION  Water Proofing Insulation Main Types Acrylic: It is a water resistant material and frequently used for waterproofing of the building roof and the floor of swimming pool. This material is composed of polyester fibers submerged in a liquid resin. It is long-life and environment-friendly material.  INSULATION  Water Proofing Insulation Main Types Liquid Waterproofing: This liquid is made from the mixing of paraffin's wax with volatile oil. The waterproofing liquid is used to spray or paint the required surfaces. Epoxy: A polymeric material sticky and has rapid solidification used to process the holes and cracks.  INSULATION  Water Proofing Insulation Main Types Rocks: Such as marble and granite. They are characterized by hard surfaces so a high resistance to the water. Sheets or layers: Surfaces could by isolated using many layers like: 1. Polyethylene membrane: Very thin layer of flexible polyethylene 2. Rubber sheets 3. Extruded polystyrene (XPS) layers. 4. Nylon 5. Metallic sheets: slabs, roofs and walls could be covered by a tiny layer of metallic sheet such as copper and aluminum plates.  INSULATION  Water Proofing Insulation Main Types Polyethylene membrane Extruded polystyrene Rubber sheets (XPS) layers. Nylon  INSULATION  Water Proofing Insulation Main Types Shingle: These tiles have good isolation and used to cover the inclined surfaces. A shingle is made of durable material like brick, stone or composite material and has a beautiful appearance. Asbestos: Light weight panels characterized by resistance to water, heat, fire, acids and fungi. The asbestos panel is often used in roofing but it is prohibited recently due to its harmful effect to the body health and environment.  INSULATION  Water Proofing Insulation Techniques of Wall Water Proofing Positive insulation: In which insulating layers are put in the same side of water. Negative insulation: In which insulating layers are put in the other side of water.  INSULATION  Water Proofing Insulation Techniques of Roof Water Proofing Traditional insulation: In which waterproofing layers are put above thermal insulation. Inverted insulation: In which waterproofing layers are put under thermal insulation. Water Transport (Permeability) It is a measure of the ability of a porous material to allow liquids to pass through it; hence it is the inversion of the resistance. The unit of permeability is Darcy (D).  INSULATION  Thermal Insulation Advantages of Thermal Insulation 1. Reduce the amount of heat transmitted through the parts of the house. 2. Reduce the energy required for heating or cooling the house. 3. Make the internal temperature of the building stable. 4. Reduce energy bills. 5. Reduce the burning of fuel in power plants.  INSULATION  Thermal Insulation Classification of Thermal Insulators  According to the structure 1. Organic materials, such as cotton, wool, cork, rubber and cellulose. 2. Inorganic materials: such as glass, asbestos, rock wool, perlite, vermiculite, foamed concrete and calcium silicate. 3. Metallic: such as aluminum foils.  According to the Shape 1. Rolls: vary in the degree of flexibility and the ability to bend or pressure. 2. Sheets: There are specific dimensions and thicknesses such as polyethylene layers, polystyrene, cork and cellulose. 3. Liquid or gaseous fluids: poured or sprayed on to form the desired layer, such as polyurethane foam. 4. Grains: a powder or granules are usually placed in the spaces between the walls and it can also be mixed with some other materials. Examples of such materials granulated cork.  INSULATION  Thermal Insulation Main Types 1. Cellulose: which is made from wood or recycled paper. 2. Cork: This is taken from cork tree. 3. Glass wool: are widely used to insulate buildings. 4. Rock wool: This material is used to isolate the buildings and storages. 5. Polyurethane: usually used as insulated panel. 6. Polystyrene cork: EPS 7. Polycarbonate panels: These sheets are lightweight panels, and are composed of several layers to be able to withstand the shocks with the presence of air cavities for the purposes of thermal insulation.  INSULATION  Thermal Insulation Main Types  INSULATION  Thermal Insulation Main Types Foamed concrete  INSULATION  Thermal Insulation Modes of Heat Transfer 1. Conduction: it is heat transfer through the wall thickness from the hot face to the cold one. 2. Convection: it is the transfer of heat due to the ambient air nearby the wall. where, the air molecules move from hot zone to cold zone carrying the thermal energy. 3. Radiation: it is the transfer of radiant heat that does not require necessarily a medium, like the heat of the sun to the earth. The reflective surfaces such as metal foils reflect thermal radiation and reduce heat absorption by the walls.  INSULATION  Thermal Insulation Modes of Heat Transfer  INSULATION  Thermal Insulation Properties o Thermal Conductivity It is the property of a material to conduct heat, defined as the time rate of steady state heat flow through a unit area of a homogeneous material induced by a unit temperature gradient in a direction perpendicular to that unit area. Heat transfer occurs at a higher rate across materials of high thermal conductivity than across materials of low thermal conductivity.  INSULATION  Thermal Insulation Properties o Thermal Conductivity The reciprocal of thermal conductivity called thermal resistivity. There are a number of ways to measure thermal conductivity of a material using the conductivity meter aperture. The unit of thermal conductivity is (W/m.K). λ= = × W/m.k Q = heat flow rate (W), A = area through which Q passes (m2), and L = thickness of the flat-slab specimen across which the temperature difference ΔT exists (m). ΔT = temperature difference (k). Thermal conductivity for common insulators  INSULATION  Thermal Insulation Properties o Thermal Conductivity  INSULATION  Thermal Insulation Properties o Thermal Conductivity  INSULATION  Thermal Insulation Properties o Reflectivity It is the ratio of reflected radiation from a surface to the total incident radiation. o Heat Capacity It is the ability of material to store the heat. The material with high heat capacity is called thermal mass. o Thermal Resistance It is the susceptibility of the material to resist the heat. Thermal resistance has inverse relation with the coefficient of thermal conductivity.  INSULATION  Acoustic Insulation Architectural Procedures to Control the Acoustics 1. Planning methods of determining the home position relative to sources of external sounds such as streets, markets and factories as well as the correct orientation of windows, doors, etc. 2. Design methods for internal spaces of the building. 3. Methods of choosing perfect soundproofing material.  INSULATION  Acoustic Insulation Architectural Procedures to Control the Acoustics 1. Planning methods of determining the home position relative to sources of external sounds such as streets, markets and factories as well as the correct orientation of windows, doors, etc. 2. Design methods for internal spaces of the building. 3. Methods of choosing perfect soundproofing material.  INSULATION  Acoustic Insulation Objectives of Acoustic Insulation 1. Prevent transmission of sound from the outside. 2. Prevent transmission of sound between the rooms through walls and ceilings. 3. Prevent the transmission of sounds and vibrations of machines. 4. Absorption of sound inside. Classification of Acoustic Insulators The incident sound upon a surface could be distributed into three main parts. The first part is reflected from the surface, the second part is absorbed by the surface while the last part is transmitted across the surface to inside. So it could say that the sound-proofing materials are divided into:  INSULATION  Acoustic Insulation Reflective Materials Absorbing Materials  INSULATION  Acoustic Insulation Main Types 1. Acoustic tiles, these tiles have the capability of sound absorption, durability and ease of cleaning. These tiles are used for the absorption of sounds of machines. 2. Glass wool or rock wool, they are characterized by the ability to absorb sound and thermal insulation, and can be mounted on the walls and ceiling. These could be used in commercial and industrial buildings. 3. Polyurethane foam which are available in the form of spray, layers and tiles. 4. Cellulose panels which are compressed and perforated face. 5. Gypsum boards with the addition of fibers to the surface.  INSULATION  Acoustic Insulation Main Types 6. Rubber, These are available in panels and rolls and they have high sound absorption and they are used to cover the walls, as well as to absorb vibrations. 7. Plastic packaging sheets: these layers fit for ceilings in factories where large dimensions. These are resistant to dust as well as the moisture. 8. Perlite, it is a good insulator of sound and heat. It gives the surface a reliable fire-resistant. Perlite is used to insulate the ceiling, walls and floors. 9. Viscoelastic damping compound (VDC), a viscous resin fast to dry, used in flooring damping, absorption of the noise as well as to absorb the vibrations of machinery and ducts. 10. Fabrics, leather, carpet and sponge materials.  INSULATION  Acoustic Insulation Main Types Polyurethane Acoustic tiles Rock wool  INSULATION  Acoustic Insulation Basic Definitions o Type of Sound It is the property that distinguishes between different types of sounds. For example, the voice of a man, an animal, a machine, etc. o Sound Power It is the energy carried by the acoustic wave in a period of time. And it is measured in watts. o Sound Frequency It is the number of times that air particles fluctuate per second as a result of sound energy passed. It is expressed in the unit of Hertz (Hz).  INSULATION  Acoustic Insulation Basic Definitions o Sound intensity It is the property that differentiates between sounds in terms of being high or low. mathematically, it is the amount of acoustic energy on a unit area. Human ear can feel a sound has 10-12 W/m2 intensity as minimum. The highest intensity of sound within earshot is 1 W/m2. o Sound Intensity Level (SIL) The sound intensity value is too small and it is difficult to compare with, so it is looking for a value more acceptable like (Decibel) which is symbolized by (dB). The lowest sound level value is zero dB.  INSULATION  Acoustic Insulation Basic Definitions Based on that, the sound is classified in terms of the level of intensity to:  0 - 40 dB : Quiet  40 - 80 dB : Noisy  80 - 120 dB : Very noisy  > 120 dB : Intolerable o Sound pressure It is the change of atmospheric pressure in a region as a result of the passage of sound. The less sound pressure feeling by human ear is about 2x10-5 Pa and this is called the hearing threshold. At a pressure of about 20 Pa the ear starts feeling of pain.  INSULATION  Acoustic Insulation Basic Definitions o Sound Transmission It means the ability of sound to move across the building from one part to another. o Transmission loss It is a measure of the sound difference in decibels through the barrier. o Sound Absorption Any substance has the ability to absorb sound in addition to its ability to reflect the sound. The energy absorbed is converted into heat. Sound absorption factor is a value describes the ability of sound absorption. The absorbance in porous materials is more than in dense solids. THANK YOU THANK YOU  STEEL Steel For Construction  STEEL Metal Classification  STEEL Utilities of Steel in Construction Field Reinforcing Steel Bars Structural Steel  STEEL Utilities of Steel in Construction Field Reinforcing Steel Bars Structural Steel  STEEL Steel Properties  Physical Properties  TENSION  Direct tension test Test Procedure 1) Mark the gage length on the specimen. 2) Place the specimen in the loading machine. 3) Attach the extensometer to the specimen. 4) Set the load reading to zero and apply load at a uniform rate. 5) Continue applying the load until failure of the specimen. 6) Record load and deformations at specified increments. 7) Calculate the stress and strain for each load increment until failure. 8) Plot the stress versus strain curve.  STEEL Direct Tension Test  STEEL Direct Tension Test  STEEL Direct Tension Test  STEEL Direct Tension Test  STEEL Direct Tension Test https://www.youtube.com/watch?v=D8U4G5kcpcM  STEEL Behavior of Steel Under Static Tension  STEEL Behavior of Steel Under Static Tension B-D large elongation with almost constant load D-E increasing the elongation with increasing the load E-F O–A decreasing the load and Extension is increasing the elongation proportional to load  STEEL Behavior of Steel Under Static Tension Mild Steel (Ductile) From point “O” to “A”: Linear proportion between loadand elongation. Point “B”: The elastic limit. From point “B” to “D”:Large elongation with almostconstant load (Yielding). From point “D” to “E”:Increasing in the elongation withincreasing in the load. Point “E”:The maximum Load (Necking). From point “E” to “F”: Decreasing in the load andincreasing in the elongation. Point “F”: Failure (Cup & Cone).  STEEL Behavior of Steel Under Static Tension Mild Steel (Ductile)  Proportion Limit It is the end point of the straight line. It can be determined only form the load-elongation curve. The curve should be drawn very accurately in order to be able to determine the proportional limit.  Elastic Limit Elastic limit is the maximum load which after removing it, the test specimen returns back to its original shape and dimensions. Value of elastic limit is very close to the value of the proportional limit.  STEEL Behavior of Steel Under Static Tension MildSteel(Ductile)  Yielding It is region in which large elongation occurs without increase in loading  Failure Mode Necking occurs before failure. Failures occurs at the shape cup and cone  STEEL Behavior of Steel Under Static Tension  STEEL Behavior of Steel Under Static Tension High Tensile Steel (Semi-Ductile) From point “O” to “A”: Linear proportion between load and elongation (Elastic Zone). No yielding. Proof load is the load corresponding to plastic elongation, non-proportional elongation, equals to a specified percentage from the gage length “Lo” (usually,Δ=0.2%Lo=0.002Lo).  STEEL Behavior of Steel Under Static Tension Cast Iron (Brittle) No elastic zone (No linear proportion between load and elongation). No yielding. No necking. Total elongation is very small (difficult to be determined).  STEEL Behavior of Steel Under Static Tension Stress Stress is the force applied to a material, divided by the materials cross-sectional area (loaded area). Strain Strain is the deformation of a material from stress. It is simply a ratio of the change in length to the original length. Strength Strength of a material is equal to the maximum stress value (resistance of amaterial).  STEEL Behavior of Steel Under Static Tension Elastic Strength - For mild steel (Ductile) Yield stress (Fy) - For high strength steel (Semi-ductile) Proof stress (Fpr) Tensile Strength Max stress (Fmax) Ductility % Elongation % Reduction of area  STEEL Behavior of Steel Under Static Tension Ductility % Elongation % Reduction of area Stiffness Youngꞌs Modulus  STEEL Bond Strength (between concrete and steel bars) o The origins of bond strength are: 1) Adhesion. 2) Friction. 3) Bearing for deformed bars. o Bond strength for deformed bars is greater than that of plain bars  STEEL Reinforcement Steel Grade Steel for reinforcement concrete Ductility P Plain Bars C or D R Ribbed Bars B 240 C - P Upper Limit Yield Strength (N/mm2) (-) : No welding Steel (W) : welding Steel  STEEL Reinforcement Steel Grade  STEEL Reinforcement Steel Grade THANK YOU  STEEL Behavior of Steel Under Compression  Compression test Is very important for most of building materials like Concrete, Building stones, Bricks, ….etc. For metals : it is done only for elements subjected to compression in order to : a) Determine the ultimate compressive strength only (like bearing plates). b) Determine the mechanical properties under compression (i.e. draw the load-deformation curve)  STEEL Behavior of Steel Under Compression  Difficulties : 1) Difficulties to have 100% true axial load (due to specimen – machine - …..) 2) Difficulties due to instability of the specimen (due to buckling) 3) Friction between machine head and specimen surface Friction will cause the following : i) increase the apparent ultimate strength of the specimen ii) non uniform increase in the diameter of the specimen (barrel shape)  STEEL Behavior of Steel Under Compression Friction is the main cause of barrel shape  STEEL Behavior of Steel Under Compression Stress-Strain curve for Ductile – Semi Ductile – Brittle metals  STEEL Behavior of Steel Under Compression  STEEL Behavior of Steel Under Compression Compression test Precautions 1. The applied load should has an accurate value (by calibration of testing machine) 2. The applied load should be vertical (spherical bearing)  STEEL Behavior of Steel Under Compression Compression test Precautions 1. The applied load should has an accurate value (by calibration of testing machine) 2. The applied load should be vertical (spherical bearing) 3. Eccentricity should be avoided 4. Buckling should be avoided (L/d ≤ 10)  STEEL Behavior of Steel Under Compression 5. Compression test specimen should satisfy the following requirements : a) Specimen opposite surfaces should be parallel b) Specimen adjacent surfaces should be perpendicular c) Specimen shape should cylindrical (circular cross section) to have uniform stress distribution near the ends of the specimen. THANK YOU  STEEL Behavior of Steel Under Static Bending (Flexure) Any structural element (like beams) can be subjected to bending by subjecting to : Pure bending moments Eccentric loads Lateral loads  STEEL Behavior of Steel Under Static Bending (Flexure) M*y f : Flexural stress (Tension or Compression) f= M : Bending Moment = PxL/4 for concentrated mid-span load I Y : Distance between outer fibers and Neutral Axis (N.A.) I : Moment of inertia of the cross section about the N.A. 148  STEEL Behavior of Steel Under Static Bending (Flexure) Flexure test is considered a very practical and easy test for any material. From this test, the following properties can be determined : 1) Elastic Flexural strength 2) Ultimate Flexural strength (Mod. of Rupture) 3) Stiffness 4) Mod. of Resilience 5) Mod. of Toughness  STEEL Behavior of Steel Under Static Bending (Flexure) 1) Elastic Flexural strength M y pl f  pl I 2) Max. Flexural strength : (Modulus of rupture) M y f rp  max I  STEEL Behavior of Steel Under Static Bending (Flexure) 3) Stiffness (Modulus of elasticity) PL3 PL3 P  E   constant 48EI 48I  4) Modulus of Resilience (MR) 1 Resilience = PP.L  LP.L 2 1 P  L Re silienc 2 P.L P.L 1 Modulus of Resilience =   F e kg mm/mm3 Volume A L 2 P.L P.L o o  STEEL Behavior of Steel Under Static Bending (Flexure) 5) Modulus of Toughness (MT) 2 Toughness...(kg.mm)  3 P max X  max 2 ( X 3 P max X  max ) Mod..of..Toughness..(kg.mm / mm 3 )  A X L  STEEL Behavior of Steel Under Static Bending (Flexure)  Cold Bend Test This test is done for ductile metals to ensure enough degree of ductility is available for forming purposes (as in stirrups) i) For Bars & Plates : The test specimens will be bent until it takes U-shape The specimen is bent around a cylinder of a radius “R” Where :  STEEL Behavior of Steel Under Static Bending (Flexure)  Modes of Failure for Cold Bend test Failure can be occurred due to : -Tension -Compression -Shear -Non homogeneity If no failure observed : the specimen Pass the test If any failure 154 observed : the specimen does not Pass the test THANK YOU  STEEL Behavior of Steel Under Shear and Torsion Introduction Shear is the case of sliding part of the body on the adjacent parts. This sliding can be happen due to shear forces or twisting moments. Shear stresses (either due to shear forces or twisting moments) are acting in a direction parallel to the cross sectional area of the body.  STEEL Behavior of Steel Under Shear and Torsion Pure Shear Due to two equal and opposite forces acting on the same line of action (theoretical case). In this case there is no eccentricity [e = 0] If e ≠ 0 then we have direct shear (practical case)  STEEL Behavior of Steel Under Shear and Torsion Direct Shear In this case there are two forces : 1) Shear force “P” 2) Bending moment (P*e) This moment can be neglected because “e” is very small. P P q  A D 2 / 4  STEEL Behavior of Steel Under Shear and Torsion There are 3 types of direct shear a) Single Shear Shear force is resisted by a single cross section “A” P q A  STEEL Behavior of Steel Under Shear and Torsion b) Double Shear Shear force is resisted by area = twice the cross sectional area “2A” q P 2A  STEEL Behavior of Steel Under Shear and Torsion c) Punching Shear In cases of punching steel plates P q dt  STEEL Behavior of Steel Under Shear and Torsion Direct shear test For Ductile metals : Failure under tension is due to Shear & Tension (cup and cone) Shear strength = 0.80 tensile strength For brittle metals : Failure under tension is due to tension only Failure under shear is due to diagonal tension Shear strength = 1.30 tensile strength  STEEL Behavior of Steel Under Shear and Torsion  STEEL Behavior of Steel Under Shear and Torsion  STEEL Behavior of Steel Under Shear and Torsion  G q Mt q   R r L J R r ɵ = Torsion angle (radian) G = Modulus of rigidity L = Length of twisted element Mt = Torsion moment J = Polar moment of inertia q = Torsional shear stress  STEEL Behavior of Steel Under Shear and Torsion Torsional shear stress for circular section Mt D 16M t q    R 4 2 3  D  D 32  STEEL Behavior of Steel Under Shear and Torsion Mt D 16M t  D q   1 1 1   (D 4  D 4 ) 2  (D 4  D 4 ) 2 1 2 1 32 Mt D 16M t  D q   2 2 2   (D 4  D 4 ) 2  (D 4  D 4 ) 2 1 2 1 32  STEEL Behavior of Steel Under Shear and Torsion  STEEL Behavior of Steel Under Shear and Torsion 1M   2 t PL P.L M.O.R  A L 1 (M  M )   2 t PL tmax max M.O.T  A L THANK YOU