Construction Materials (CMT) PDF

**Construction Material**s - defined as the materials, supplies, fixtures, or equipment, any combination of such items. 7 Types of Common Construction Materials: 1. **Steel** - metal alloy of iron and carbon and often other alloying material in its composition to make it stronger and more...

**Construction Material**s - defined as the materials, supplies, fixtures, or equipment, any combination of such items. 7 Types of Common Construction Materials: 1. **Steel** - metal alloy of iron and carbon and often other alloying material in its composition to make it stronger and more fracture-resistant than iron. 2. **Aggregate** - is a broad category of particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are the most mined materials in the world. They are divided into two categories: fine aggregates and coarse aggregates. 3. **Cement** - in general, adhesive substances of all kinds, but, in a narrower sense, the binding materials used in building and civil engineering construction. Cements of this kind are finely ground powders that, when mixed with water, set to a hard mass. 4. **Bitumen** - A black viscous mixture of hydrocarbons obtained naturally or as a residue from petroleum distillation. It is used for road surfacing and roofing. 5. **Concrete** - is a composite material made of fine and coarse aggregate (think gravel, crushed stone, recycled concrete, and geosynthetic aggregates) bound together by a liquid binder such as cement that hardens or cures over time. 6. **Asphalt** - is a mixture of aggregates, binder and filler, used for constructing and maintaining roads, parking areas, railway tracks, ports, airport runways, bicycle lanes, sidewalks and also play- and sport areas. 7. **Masonry** - construction uses individual units (such as bricks) to build structures that are usually bound together by some kind of mortar. The strongest and most commonly used masonry unit now is a concrete block, which may be reinforced with steel. **Materials testing** - is a respected and established technique which is used to ascertain both the physical and mechanical properties of raw materials and components. It can be used to examine almost anything from human hair to steel, ceramics or composite materials. Five major categories of materials testing: **Mechanical Testing** - also known as destructive testing, reveals the properties of a material under dynamic or static force. Designed to ensure that materials are suitable for their intended applications. **Testing for Thermal Properties** - testing for thermal properties is used to measure materials' ability to transfer heat since it differs with each substance and may depend on structure, density, humidity, pressure and temperature. **Testing for Electrical Properties** - materials are subjected to electrical stresses under a variety of controlled conditions, including liquid contaminants, dust and fog, dry air electrical arc, or high voltage dielectric breakdown conditions. **Testing for resistance to corrosion, radiation and biological deterioration** - testing for breakdown or deterioration of materials under exposure to a particular type of environment has greatly increased in recent years. **Non-destructive testing** - a testing and analysis technique to evaluate the properties of a material, component, structure or system for characteristic differences or welding defects and discontinuities without causing damage to the original part. Tests carried out on different construction materials: 1\) **Aggregates** a. **Sieve Analysis **-- determines the particle size distribution of aggregates using a set of sieves with different sizes. It helps classify aggregates as coarse or fine and ensures they meet grading requirements.\ b. **Water Absorption Test** -- measures the amount of water an aggregate can absorb. It indicates the aggregate\'s porosity and affects concrete mix design.\ c. **Aggregate Impact Value Test** -- evaluates the toughness of aggregates by measuring the percentage of fines produced after applying an impact load.\ d. **Aggregate Abrasion Test** -- determines the resistance of aggregates to surface wear using the Los Angeles Abrasion test or the Deval abrasion test.\ e. **Aggregate Crushing Value Test** -- assesses the strength of aggregates by measuring the percentage of fines generated after applying a compressive load. 2\) **Bitumen** a. **Determining Bitumen Content **-- measures the bitumen percentage in bituminous mixtures using the ignition method or solvent extraction.\ b. **Determining the Flash and Fire Point of Bitumen** -- determines the temperature at which bitumen gives off vapors that can ignite (flash point) and sustain combustion (fire point).\ c. **Penetration of Bitumen** -- measures the hardness of bitumen by assessing how deep a standard needle penetrates under a fixed load and temperature.\ d. **Softening Point Test** -- Identifies the temperature at which bitumen softens using the Ring and Ball test.\ e. **Determining the Specific Gravity of Bitumen **-- determines the ratio of the density of bitumen to the density of water, indicating its purity and consistency.\ f. **Determining the Ductility** **Test **-- Measures the elongation of bitumen before breaking, ensuring it has adequate binding properties.\ g. **Marshall Stability Test** -- Determines the stability and flow properties of bituminous mixtures under loading conditions. 3\) **Cement** a. **Fineness Test** -- use sieve analysis.\ b. **Soundness Test** -- measure the ability of cement to resist the volume expansion.\ c. **Consistency Test** -- trial and error. d. **Setting Time Test **-- determines the time required for cement paste to change from a fluid state to a hardened state. This test is performed using the Vicat needle apparatus. 4\) **Fresh Concrete** a. **Slump Test** -- Evaluates the workability and consistency of fresh concrete by measuring the slump of a cone-shaped specimen.\ b. **Compacting Factor Test** -- Determines the degree of compaction of concrete, particularly for low-workability mixes.\ c. **VeBe Test** -- Measures the time taken for fresh concrete to fully compact under vibration, useful for very dry mixes.\ d. **K-Slump Test **-- A rapid test to assess workability and consistency using a special K-slump tester. 5\) **Hardened Concrete** a. **Compression Strength Test** -- measures the compressive strength of hardened concrete by crushing a cube or cylinder specimen under axial load.\ b. **Flexural Strength Test** -- determines the tensile strength of concrete by applying a load at the center of a beam specimen.\ c. **Rebound Hammer Test** -- also known as the *Schmidt Hammer Test*, is a non-destructive test used to estimate the compressive strength of hardened concrete.\ d. **Ultrasonic Pulse Velocity (UPV) Test** -- measures the velocity of ultrasonic waves passing through concrete to assess its quality, uniformity, and strength. 6\) **Steel Reinforcement** a. **Tensile Strength Test** -- determines the tensile properties of steel reinforcement, including yield strength, ultimate strength, and elongation.\ b. **Bend Test** -- assesses the ductility of steel by bending a specimen to a specified angle without cracking.\ c. **Re-bend Test **-- evaluates the effect of strain aging by bending, aging the specimen in hot water, and re-bending it to check for cracks.\ d. **Shear Test **-- determines the shear strength of steel bars by applying a direct shear force.\ e. **Brinell Hardness Test** -- measures the hardness of steel by pressing a steel or tungsten carbide ball into the surface under a standard load.\ f. **Impact Test **-- assesses the toughness of steel under sudden impact using the Charpy or Izod test.\ g. **Torsion Test** -- determines the torsional strength and deformation of steel under twisting forces. **Why is CMT important?** Because it is critical for the viability and safety of a construction project. CMT can reveal any number of issues related to construction quality. It can highlight future risks, help classify a building site, and assist with engineering decisions. Without CMT, engineers and builders may not know if the quality of the construction meets the requirements. Apparatus and Equipment Used in Testing of Materials: 1. **CEMENT/MORTAR** **Cement Testing** **Cement Tests** are performed to know the strength, characteristics, and properties of cement. Various tests on cement are conducted to check its quality. **Various Tests for Cement/Mortar:** a. **Fineness Test** \- the fineness of cement is a measure of cement particle size and is denoted in terms of the specific surface area of cement. \- the test is done by sieving cement samples through a standard IS sieve. b. **Initial and Final Setting Time Test** **Initial Setting Time of Cement** - it is the time elapsed between the moment water is added to the cement and the time when the paste starts losing its plasticity. **Final Setting Time of Cement** - it is the time elapsed between the moment water is added to the cement and the time when the cement paste loses its plasticity completely and attains sufficient firmness to resist certain definite pressure. c. **Standard Consistency Test** The standard consistency of cement paste is defined as the percentage of water added in a 300g weight of cement, which will permit a Vicat plunger having 50 mm length and 10 mm diameter to penetrate in cement paste to a depth of 33-35 mm from the top of the mold. d. **Soundness Test** \- the soundness of cement indicates the stability of any cement during the volume change in the process of setting and hardening. \- in case the volume change in cement is unstable after setting and hardening, the concrete element will crack, which can affect the quality of the structure or even cause serious accidents, known as poor dimensional stability. e. **Specific Gravity Test** \- the specific gravity of cement is defined as the mass of cement of a specified volume to the mass of water of the same volume of cement. \- it can also be defined as the density of cement to the density of water for the same volume. **Equipment Used in Cement Testing:** a. **Vicat Needle Apparatus** - Vicat apparatus is a penetration device used in testing hydraulic cements and similar materials to determine their normal or standard consistency. It is also used to determine the initial setting time and final setting time of hydraulic cements and similar materials. b. **Flow Cone Apparatus** \- it is used for viscosity and fluidity determination of mortars, muds, grouts, fluid materials, etc. c. **Flame Photometer** \- it is used to determine the alkali content of cement.  d. **Automatic Mortar Mixer** \- it is designed for the efficient mixing of cement pastes and mortar, with two automatic sequences of the mixing cycle. e. **Bulk Density of Cement Set** \- this apparatus is used for the measurement of the apparent density (bulk density) of powder and non-cohesive materials. \- it consists of a sieve funnel with tripod, unit weight measure (1-liter capacity) with hopper, spatula, straight edge, and a large spoon. f. **Le Chatelier Mold** - used for determining the expansion of cement. The mold consists of a spring-tensioned split cylinder (30 mm internal diameter, 30 mm high) with two indicator stems measuring 165 mm from the centerline of the cylinder and an O-ring. Two or three molds are required for each test. A water bath is also required to perform the test. g. **Le Chatelier Flask** Used to determine the specific gravity of hydraulic cement and lime. Glass flask (250 ml capacity), with graduated neck from 0 to 1 ml and from 18 to 24 ml in 0.1 ml increments, with accuracy of 0.05 ml. Weight approx.: 500 g. h. **Le Chatelier Water Bath** Used for the determination of setting time and expansion of cement samples. Constructed with a stainless steel inside chamber and an exterior case in painted steel sheet. It can hold up to 12 Le Chatelier molds (to be ordered separately) in the removable rack, supplied with the bath. The bath reaches the boiling point in approximately 30 minutes. i. **Cement Mortar Permeability Apparatus** \- used to determine the permeability to water of cement mortar specimens with or without waterproofing compounds. \- It comprises three brass/gunmetal cells mounted on a stand and a pressure chamber with a pressure regulator. The cell can accommodate 100mm diameter × 50mm high specimens. Each cell assembly consists of a base plate with an outlet for water and is recessed to hold the specimen in place with a ring washer in between. The top plate has an inlet for water and a suitable connector for the application of pressurized water in the cell. The mold and collar are clamped between the base plate and top plate with the help of four tension rods and nuts. The cells are mounted on a stand. 2. **CONCRETE** **CONCRETE TESTING** \- a concrete test is performed to learn more about the properties of a specific sample of concrete. A number of different tests can be performed on concrete both on a job site and in a laboratory. **Various Tests for Concrete:** a. **Air Content Test** Measures the total air content in a sample of fresh concrete. Does not indicate the final in-place air content because a certain amount of air is lost during transportation, consolidation, placement, and finishing. b. **Concrete Slump Test** The test measures consistency of concrete in that specific batch. It is performed to check the workability of freshly made concrete. Consistency refers to the ease with which concrete flows. Used to indicate the degree of wetness. Wetter mixes are more workable than drier mixes. Concrete of the same consistency may still vary in workability. The test is also used to determine consistency between individual batches. c. **Compressive Strength Test** Out of many tests applied to concrete, this is of utmost importance as it provides an idea about all characteristics of concrete. By this single test, one can judge whether concreting has been done properly or not. d. **Curing Test** Curing plays an important role in strength development and durability of concrete. Curing takes place immediately after concrete placing and finishing. It involves maintaining the desired moisture and temperature conditions both at depth and near the surface for extended periods of time. Properly cured concrete has: Adequate moisture for continued hydration and strength development, volume stability, resistance to freezing and thawing, abrasion and scaling resistance. e. **Flow Table Test** The flow table test or flow test is a method to determine the consistency of fresh concrete. This test is also used to identify the transportable moisture limit of solid bulk cargoes. If consistency is not at the desired level, concrete will not have the required strength and other qualities once it has set. If concrete is too pasty, cavities may form within it, leading to: corrosion of rebar, cracks in the concrete, and reduced concrete strength. **Equipment Used in Concrete Testing:** a. **Compression Testing Machine** This Compression Testing Machine is a hydraulic, electrically operated unit, designed for conducting compression tests on concrete specimens up to 20 cm. Diameter (or width and depth) and 30 cm, in height and also rocks and various other materials. b. **Flow Table** This equipment is used to determine the flow of concrete. The apparatus consists of a flow table, stainless steel flow mould, tamping bar. The steel cone, part of the apparatus, has a top dia. of 130 mm a base dia. of 200 mm and is 200 mm high. All metal parts are protected against corrosion. c. **Flexural Testing Machine** It has a range of 100 kN and 200 kN capacity flexure testing machines have been designed to meet the need for reliable and consistent testing of flexural test on standard concrete beams, transverse test on kerbs and flagstones, indirect tensile tests on concrete and interlocking pavers. d. **Mortar Mixer** It is used for mixing cement pastes, mortars and pozzolona. e. **Gauging Trowel** It is a round-nosed trowel used for mixing mortar and applying small amounts in confined areas; it is also used to replace crumbled mortar and to patch concrete. f. **VeeBee Consistometer** It is used for workability as well as consistency for fresh concrete. A slump cone and a graduated rod supplied with the instrument helps the operator to find out slump values and Vibration Table with container and acrylic disc is used to find out workability of concrete expressed in Vee Bee degrees. Vee Bee Degrees is defined as the time in seconds to complete required vibrating at which the fresh concrete flows out sufficiently to come in contract of the entire face of acrylic disc. g. **Slump Test Apparatus** It is used for the determination of the consistency of freshly mixed concrete, where the maximum size of the aggregate does not exceed 38mm. It consists of one slump cone with handles and foot pieces. The slump cone has internal dimensions 20cm. dia at base 10cm. top dia. and 30cm height. Foot pieces can be fixed to the clamps on the base plate. The base plate has lifting handle for easy transportation. One graduated steel rod 16mm dia x 600mm long, rounded at one end and graduated in mms. h. **Compaction Factor Apparatus** Designed to undertake a more precise and sensitive test procedure than the simple slump test. The apparatus consists of two conical hoppers mounted on a cylinder. Each hopper has a hinged flange with quick release mechanism and everything is mounted on a rigid steel stand. The compacting factor is the ratio between the weight of the partially compacted concrete and the weight of the fully compacted concrete. Dimensions: 500x400x1510 mm Weight: 55 kg. i. **Kelley Ball Penetration Apparatus** A test for the consistency of concrete using the penetration of a half sphere; a 1-inch (2.5-centimeter) penetration by the Kelly ball corresponds to about 2 inches (5 centimeters) of slump. Determines depth of penetration of metal weight into plastic concrete. Apparatus consists of 30 lb. (14kg) cylinder with hemispherically shaped bottom and handle. The stirrup (frame) guides the handle and acts as a reference for measuring depth of penetration. Handle is graduated in 1/4\" (6.4mm) increments on one side and half-centimeter increments on the other side. Concrete may be tested as placed in the forms prior to any manipulation or in a suitable container. 20lb version can be used with lightweight concrete. j. **Cube Mold** The standard size of cube is 150 mm. Cubes of 100 mm size are not suitable for concrete having a nominal maximum aggregate size exceeding 20 mm. Cubes of 150 mm size are not suitable for concrete having a nominal maximum aggregate size exceeding 40 mm. k. **Cylindrical Mold** Hard plastic and steel cylinder moulds are manufactured in accordance with dimensions and tolerances stated in the related standards. Two part and clamp attached base plate cast iron, plastic and steel moulds are designed to be durable, corrosion resistant and easy to clean. l. **Beam Mold** For casting concrete specimens for flexure tests. Specification: Made of cast iron. The moulds are made of 4 plates assembled together. Each mould is supplied complete with base plate. Faces are machined flat to +/-0.2mm and finished in size to 0.2mm