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Precautions to Be Taken While Working with Soil Drying Oven

Laboratory ovens are designed and built for drying a range of materials like concrete, rock, soil, asphalt, and aggregates. They come in various litre capacities, with temperatures control ranging from ambient to 250°C. The interior of a high-quality soil drying oven is made from stainless steel , and the exterior is crafted from sheet steel then finished in a powder-coated paint. It functions with forced convection or fan-circulation and is equipped with an analogue over-temperature protection thermostat and a digital control unit for direct reading. Proper usage and safety precautions must be observed when using a soil drying oven, as it poses health and fire hazards to users and its immediate surroundings. The following are some of the hazards you must be aware of: Health hazard – Volatilised substances can pose chronic or acute respiratory hazards. Burn hazard – The oven chamber becomes extremely hot, causing surfaces and materials to be dangerous when

How A Pull Off Adhesion Tester Works?

A pull-off tester measures coating adhesion to rigid substances like wood, concrete, and metal. It relies on a hydraulic system to pull away a test disk which is glued to the substrate material. The tester records the force applied when failure occurs. The pull off adhesion tester is widely used in quality assurance in construction to save time, as it is a reliable means to make sure that there is enough adhesion between the substrate and the coating. Here’s how the device works: Manual mode - The tester is available in both automatic and manual modes. The manual hydraulic pump applies continuous and smooth pressure using a single stroke. Use the pull rate indicator to monitor and adjust the rate of pull manually. The internal memory can store the maximum pull-off pressure, test duration, rate of pull, and the dolly size for a maximum of 200 pulls. A manual pull off adhesion tester is compatible with PosiSoft software , so you can interpre

Evaluate the Shearing Strength of Sandy Soil Using the Direct Shear Test Apparatus

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The purpose of the direct shear test is to find soil’s shearing strength. A special type of apparatus is required to evaluate sandy soil’s shearing strength, which will help predict the material’s suitability for building foundations and for supporting retaining walls, slab bridges, sheet piling, and pipes. The test should also be able to identify the value of internal friction’s angle and soil cohesion when designing structures. One of the most advanced direct shear test apparatus is an automatic direct and residual shear testing machine , which comes with a carriage assembly, load hanger, and the integral 10:1, 11:1, and 9:1 lever loading device. A high-end direct shear test apparatus is designed to be floor mounted and motorised. A beam loading device is supplied to strengthen the shear box assembly’s vertical load, and it can handle up to 50kg. The total load on the specimen can reach up to 5kM. The machine is compatible with various round and square shear box assemblies,

Determine the Suitability of Aggregates with Los Angeles Abrasion Testing Machine

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The Los Angeles test determines the rate of degradation of the mineral aggregates of a standard grading as a result of the combination of actions including abrasion, grinding, and impact. It is conducted with a steel drum, which can be rotated and contains a specific amount of steel spheres. A Los Angeles abrasion testing machine is a conventional method for indicating abrasion characteristics and aggregate toughness. To produce high-quality Hot Mix Asphalt (HMA) it is crucial to identify aggregate abrasion characteristics by ensuring the constituent aggregate can resist disintegration, crushing, and degradation. The performance of aggregates must be determined before they are used in road base applications and paving. The Los Angeles abrasion machine evaluates resistance to wearing and fragmentation caused by friction. A sample of the aggregate is placed in a drum and tumbled inside for a fixed amount of revolutions. High-quality testing machinery comes with a safety stop on t

Steps to Follow While Using a Schmidt Hammer

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The Schmidt Hammer is a valuable instrument for testing concrete. Inside the hammer is a sensor that measures the rebound value of the test impact with repeatability and high resolution. The hammer is also known as a ‘rebound hammer’, with ‘rebound’ pertaining to the effective, non-destructive way to measure the compressive strength of concrete to within a 20 percent range, and the control of uniform concrete quality in prefabricated structures and in-situ concrete. Certain steps must be followed to ensure accuracy and proper use of the Schmidt Hammer . Here are some of the guidelines to consider: Refer to ASTM C805-13 – The standard test method with a Schmidt hammer is listed under ASTM. The latest standard provides the procedures for the test method for rebound number of hardened concrete.   Calibrate the hammer – A good supplier offers equipment with calibration certificates and recalibration services.   Make sure the concrete is ready f

Measuring Metallic Corrosion with Half Cell Potential Test

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When reinforcing steel corrodes inside concrete, an electro-chemical process occurs and its characteristics can be identified with a half-cell potential (HCP) measurement, also known as a ‘half cell potential test’. HCP measures metallic corrosion to determine the regions of potential corrosion and the risk it can impose on the structure. Date interpretation is nuanced and specific to particular sites, but generally a more negative potential means a risk of corrosion occurring in unsaturated marine exposed concrete. To conduct the test, an electrode is used to form one part of the bimetal cell, while the reinforcing steel within the concrete serves as the other half. Silver/silver chloride in a potassium chloride solution or a simple Copper/Copper Sulphate cell is the ideal reference electrode for use on-site. An electrode that is made of copper/copper sulphate is widely used, too. An advanced half cell potential meter is a great instrument to have for a more reliable way to

Useful Applications of Ground Penetrating Radar

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Ground penetrating radar (GPR) is state-of-the-art equipment used for exploring the subsurface of the earth. The cutting-edge imaging technology found in high-end GPR systems measures electromagnetic wave propagation and echo from the subsurface, which images and identifies changes in the magnetic and electrical properties beneath the surface of the earth. Hence, GPR systems are useful in locating underground utility lines in earth or post tensioning and reinforcing in concrete. Ground penetrating radar is surprisingly versatile for many other applications, including forensic research, land surveying, detecting unexploded land mines, conducting groundwater studies, and monitoring the structural integrity of airplane runways. GPR is useful in many different fields. It is used to study ice, groundwater, soil, and bedrock under earth sciences and it may be helpful in finding diamonds and gold nuggets in alluvial gravel beds. In that case, ground penetrating radar is used to fi

Precautions to Be Taken While Using a Piezometer

The piezometer is a measuring device that determines pore pressures underground and liquid pressure. By determining pore pressure, you can understand the behaviour of the ground before, during, and after a construction project. Certain precautions must be taken when using a piezometer to ensure proper usage and the accuracy of results. Here are some of them: Have the right equipment – Invest in a state-of-the-art piezometer that uses a proven method of converting fluid pressures on the sensitive diaphragm into frequency signals which are ideal in the demanding environment common with civil engineering applications. Modern piezometers are capable of long distance signal transmission without degradation. They can tolerate wet wiring conditions and resist external electrical noise, too. Some manufacturers make piezometers specific for different applications, for instance, you should be able to find one with a heavy-duty body that can be b

Know About Concrete Strength Test and Its Application

Hardened concrete can be tested to determine its strength and quality. Concrete strength tests are designed to determine the compressive strength of the material and its ability to resist loads. Here are some of the things you should know about it: Why it’s done – Compressive strength tests are conducted to ensure that the concrete mixture being used for construction can meet the requirements for specified strength in a given job specification. How it’s done – Concrete cylinders must be created and cured following the procedures described in the AS1012.8 for cured specimens before they are tested.  That way, you can be sure that you can conduct the concrete strength test correctly and the results will be reliable.. Cylindrical specimens are tested following AS1012.9, under the test method for compressive strength of cylindrical concrete specimens. The formula - Concrete’s compressive strength is measured by div

Importance of Ultrasonic Pulse Velocity Test in The Construction Industry

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In the construction industry, it is important to ensure that structures are built properly using the highest-quality materials and construction methods. Hence, certain tests must be conducted to ensure the quality of certain materials. The ultrasonic pulse velocity test is one of the most essential tests designed to determine the quality of natural rock and concrete. This testing method is preferred because it is non-destructive and it is conducted on site, saving builders a lot of time and money. In an ultrasonic pulse velocity test, the quality and strength of rock or concrete is determined by measuring the velocity of the ultrasonic pulse, which passes through the natural rock formation or concrete structure. The test is conducted using specialised equipment that generates a pulse of ultrasonic wave and measuring the time it takes for that pulse to go through the concrete. A high velocity indicates that the material is continuous and high-quality, and a slower velocity may

Features & Applications of Piezometer in Construction

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In geotechnical and civil engineering different tools are required and utilised to ensure a high-quality construction. The piezometer is one of the devices that is helpful in measuring pore water pressure. Some of the most advanced piezometers come with a vibrating wire, making them more effective in the method of converting fluid pressure into a frequency signal on a sensitive diaphragm. Frequency signals can be used in demanding environments, making them ideal in applications involving civil engineering. The signals are capable of being transmitted in long distances without degrading. Moreover, they are resistant to electrical external noise and they can tolerate wet wiring conditions. A vibrating wire gauge works based on the principle that when a tension wire is plucked, it vibrates at a resonant frequency. A magnetic coil surrounds the wire, and when plucked by a data logger interface, the result is the vibration’s resonant frequency. Changes in the distance between the

All That You Need to Know About Universal Testing Machine

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Universal testing machines are used to measure the force being applied to various materials and the deformation that occurs as a result. They are commonly used for testing the strength of steel reinforcing bars while under tension. They can be used to conduct tests to determine a material’s shear, flex or bend, peel, tear, puncture or burst, friction, torsion, friction, heat distortion temperature, and stiffness, too. Some of the most common types of universal testing machines are hydraulic and electromechanical testing equipment, which are designed, developed, and manufactured to conform to various standards. Some machines can be more versatile with the addition of certain types of accessories, like load cells, fixtures, grips, and platens. ‘Universal’ pertains to the many different types of standard compression and standard tests on structure, components, and materials. A basic universal testing machine will have the components including the load frame that typically consist

A Look into Soil Testing Equipment

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Soil is the base of foundations for any construction project. It acts as a support for roads and other crucial infrastructure. It makes good sense to ensure that you are building on an appropriate soil before construction begins. Soil testing provides information that can help construction companies and engineering firms determine the mechanical behaviour of soils. Testing can be conducted using the right equipment and accessories that go with them. High-quality soil testing equipment can characterise the soil samples on site or in the laboratory. Some equipment lets you collect soil samples, classify soils, and evaluate the mechanical property of the material. Here are some of the different types of soil testing equipment : CBR test machines – California Bearing Ratio is the test for measuring subgrade soil and highway sub base and subgrade strength. The process involves a penetration test, and the machines are ideal for testing cohesive materials, which are

Importance of Soil Testing Equipment for Construction Companies

Soil testing is a mandatory task for construction companies because it lets them predict the mechanical behaviour of soils which will become the support for infrastructure and roads or serve as the base of foundations for buildings. To save time and effort, construction companies must invest in high-quality soil testing equipment that is suitable for characterising soil samples in laboratories. Likewise, they must consider using high-end on-site testing equipment. Many different types of soil testing equipment support soil classification, the collection of soil samples, the evaluation of soil’s mechanical properties, and the testing of completed sub bases and road bases on site. Construction companies rely on soil testing equipment to examine the geotechnical and chemical properties of soil. They can determine if the soil is suitable for the construction project and if it can accommodate the building in the long run. Soil testing equipment is useful in identifying the kinds of so

Evaluate the Quality of Concrete by Ultrasonic Pulse Velocity

Checking the quality and durability of natural rocks and concrete is essential to ensure the stability and strength of a structure. To do that, you need to conduct an ultrasonic pulse velocity test, a non-destructive and in-situ testing method that assesses the quality and strength of concrete or rock. In this test, the velocity of the ultrasonic pulse through a concrete structure is measured. An ultrasonic pulse velocity test is conducted by letting a pulse of ultrasonic wave pass through a known distance of material, then measuring the time it takes for the pulse to go through the structure. A higher velocity pertains to a high-quality and durable material, while slow velocities may indicate defects like voids and cracks in the concrete or less dense materials. An ultrasonic pulse velocity test can be conducted quickly with more reliable results with the right testing equipment. Testing machines typically have a pulse generation circuit and a pulse reception circuit to receive

Benefits of Ultrasonic Concrete Testing Equipment

The right equipment can make it easier to examine and determine the quality of concrete. Ultrasonic pulse velocity testing equipment is one of the most essential instruments that you can use for conducting tests on concrete. High-quality ultrasonic concrete testing equipment offers data acquisition, complete control of transmission parameters, and waveform analysis. It can conduct conventional pulse velocity and transit time measurements, as well as surface velocity, perpendicular crack depth, and path length measurements. High-end ultrasonic concrete testing equipment comes with an optimised pulse shaping for better transmission range, even with lower voltage levels. Together with automated receiver gain and transmitter voltage, the equipment ensures optimum signal levels for stable and accurate measurements.  Modern ultrasonic concrete testing equipment is a touchscreen unit that can control traditional ultrasonic pulse velocity transducers and pulse echo transducers. A materia

A look into Concrete Compression Testing

The concrete compression test is conducted to determine the compressive strength of concrete structures. In a concrete compression test, a concrete specimen is formed into a cylinder or cube, allowed to set for a period of time and then tested in a laboratory using a specially designed machine. The size of the specimen depends on where the test is conducted. For instance, 150mm cubes are the norm in European and Asian countries and in Russia, while cylinders are used in Australia and the US.  Concrete specimens are typically created and cured for 28 days on-site before being sent to the laboratory to be tested, but there are times where the testing may occur after one, three, seven, or 14 days of curing. When the specimen is placed in concrete compression test machine, pressure is constantly applied until failure cracks appear, the machine will detect the rapid drop in pressure when a break occurs.  There are different  types of concrete compression test machines . A manual f

Why You Need to Do Concrete Strength Test?

Concrete must be tested for quality assurance. At times, it is conducted for assessing structural conditions in their final form and before performing any repairs on a structure. The compressive strength of concrete is determined as an estimate by correlating mechanical properties like ultrasonic wave velocity and surface hardness with lab-based destructive tests. Concrete strength is measured by a compression test, which will determine the ability of the material to resist loads that may compress it. Compressive strength is determined by crushing a cylindrical specimen of concrete in a compression testing machine.  The results of a compressive strength test can be used to determine if the concrete mixture delivered to the construction site is able to meet the specified strength requirements for the job. Concrete cylinders are produced and cured following the procedures indicated in ASTM C-31, and the specimens are tested according to ASTM C-39. The test results depict the aver

Information about the Concrete Compression Test

Concrete compression testing is a crucial aspect of the construction process. Concrete is tested to make sure that the material specified and purchased is consistent with what was delivered to the construction site. There are many different testing methods to determine concrete compression, and they typically involve the use of specially designed tools and equipment to make sure that the procedure follows industry standards.  Concrete compression tests are typically conducted in a lab. Cylinder samples are used and operators follow AS1012 to ensure the correct procedure, sampling equipment, and other tools to be used for the test. The same standard specifies the requirements for determining the indirect flexural strength of concrete by splitting, and generic flexural testing.  The concrete compression test is actually the most widely conducted testing method to determine the compressive strength of concrete. Cylinders and cube samples are typically used for the test, but th

How Can A Slump Test Be Beneficial?

A concrete slump test measures the consistency of the material in a specific batch to determine the consistency, workability, and texture of the freshly made concrete. In a slump test, consistency determines the ease with which the material can flow. Hence, the test can help indicate the degree of wetness. Testing lets you determine the workability of the concrete, where wetter concrete is more workable compared to a drier mix, although the one with similar consistency can vary in its workability. The test can be used to determine the consistency of different batches of concrete, too.  To conduct a slump test , you need materials like the slump cone, base plate, slump funnel, a tamping rod, a ruler, and a mallet. The simplicity of these devices makes slump testing cost-effective in determining the workability of fresh concrete. In a test, the slump cone must be filled in layers, and each later will be compacted with the rod. The cone is then taken away and the vertical drop of

Concrete Corrosion and How to Prevent It

Concrete corrosion is a type of physicochemical, colloidal, or chemical disintegration and deterioration of solid structures and components and it is usually caused by reactive gases and liquids. It is a defect that can cause widespread damage to assets. Hence, it makes sense to make sure that preventative measures, testing, and coatings are applied to prevent or at least reduce the speed of corrosion. The corrosion of concrete reinforcement usually depends on the porosity and cover thickness of the concrete layer. Likewise, it may depend on environmental conditions, especially when those physical and geometrical properties are unable to meet requirements.  Reinforced concrete is typically designed and constructed with an estimated life span, which is controlled by asset-owners and designed by designers. The structure must be in a state of deterioration to the point that it cannot fulfil its functions any more. To prevent concrete corrosion, steps like controlling the quality and