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Showing posts from February, 2016

Know a How Crack Measuring Device Works

Cracks are likely to occur on concrete structures over time, and they could indicate underlying damage that must be addressed as soon as possible. For this reason, civil engineers rely on crack measuring devices to determine the size and the depth of cracks. There are many different crack measuring devices that are used for different applications. Here are some of them: Digital Position Strain Gauge Deformation Meter: This device is one of the most precise options for crack measuring equipment. It comes with a digital dial gauge, which is attached to a bar. A conical point is fixed and mounted at one end of that bar, and a moving conical point at the other end. There is a setting out bar to position pre-drilled stainless steel discs, which are then attached to a structure with an adhesive. The conical points are inserted into holes in the discs when a reading must be made. This way, any strain changes in the structure are translated into a change on the dial gauge's read

Uses for Universal Testing Machine

Universal testing machine or UTM is aptly named as it can perform various types of tensile and compression tests on different materials. There are also many different terms used to refer to a UTM that you will commonly hear in the industry, among the most popular of which are a tensile tester, bend tester, and compression tester. Some types of UTMs are stripped of some capabilities and/or are marketed to specific sectors, like texture analyzers for food, peel tester for adhesives, labels, and tapes, and top load compression tester for pipes and packaging. True UTMs can perform all of these and more. They are great multi-purpose instruments for any QC or R&D laboratory. The following are only a few common uses for UTMs: Tensile testing – One of the most common applications for UTM, a tensile test measure how strong a material is, how long it can stretch, and how stiff it is as the material is pulled apart until breaking point. Compression testing – Compr

CBR Test – Ensure the Quality before Using

CBR stands for 'California bearing ratio' and it is a test that measures the strength of highway subgrades and base courses through penetration. It can test cohesive materials that have a less than 19mm particle size. There are different kinds of CBR test machines you can use for various applications. You must ensure their quality and the right equipment before you perform the test. A CBR test machine that comes with a dial gauge and load ring can measure the force and piston travel. It has a 50kN capacity and two travel speeds, which are 1mm/min and 1.27mm/min. There are CBR test machines that come with a digital readout to determine digital force and travel, too. Both are laboratory machines that can provide an accurate measurement of the strength of the structure or material. Automatic CBR test machines are among the most advanced, with varied ram speeds between 0.5 and 5mm/min. They are compatible with testing and data acquisition software. In an automatic CBR

Benefits of Concrete Compression Test

Concrete testing is performed in order to evaluate the properties of concrete. There are several different tests that can be done to study concrete's strength, structural integrity, and suitability for various applications and these tests can be done either in a laboratory or right on the job site. Concrete is one of the most common and arguably the most important structural element for most building projects. Because of this, testing of its quality is mandatory in many jurisdictions. However, apart from due diligence, concrete testing, particularly compression testing, also ensures the consistency and the safety of the material, allowing manufacturers, builders, and contractors to ensure end clients that their finished products are of the highest quality and are fit for purpose. Other benefits of concrete compression testing include : Determining batch quality Determining consistency in production or manufacture Aiding in the design process Reducing ma

When to Use Concrete Resistivity Meter

Concrete electrical resistivity is obtained by applying current into the concrete surface and measuring the resulting response voltage. Different methods for measuring concrete resistivity exist, ranging from laboratory two-electrode, four electrode and transformer methods to onsite four probe and rebar methods. The electrical properties of concrete depend largely on its moisture content. Concrete may, therefore, exhibit insulated or conductive characteristics depending on its moisture levels. For instance, a concrete sample could exhibit high electrical resistance when dry and at the same time have lower a resistance when it is saturated. Concrete also has capacitive properties, meaning it can hold an electrical charge, making it difficult to measure electrical resistance. Nevertheless, several methods and approaches for measuring the electrical resistivity of concrete are available, and of those, the four-probe method is considered the most suitable for onsite investigatio

Half Cell Potential Meaning and Usage

Half cell potential in general and technical terms, corresponds to a steady state of electrical current between metal dissolution and the equivalent reduction reaction, leading to the formation of OH- or ions hydroxyls from oxygen gas. In concrete, the dissolution zones are usually rather large (often a centimeter or more) and fixed. A current line or electric field connects the zones to areas where oxygen is reduced. For a given value of the potential, these electric fields are normal on equipotential surfaces, and can then be intersected by the concrete surface. The potential value can then be measured using a reference electrode on the surface of the concrete. Half cell potential is the parameter used or evaluating the steel reinforcement condition of the concrete. The corrosion of reinforcing steel is primarily an electro chemical process and the resulting behavior of the metal can be characterized and analyzed by determining and measuring its half cell potential. The gre

What Do You Mean By Concrete Corrosion?

Concrete corrosion pertains to the degradation that occurs within and outside the material. Concrete can degrade due to various reasons, usually due to material limitations, construction methods, the design, and constant exposure to severe conditions. Structural, functional, and aesthetic problems may occur due to fire damage, effects of sea water, aggregate expansion, calcium leaching, bacterial corrosion, chemical damage, and physical damage. Corrosion of concrete can lead to widespread damage to critical assets and structures, like bridges and sewage pipelines. Preventative measures like coatings (i.e. lacquer or oil-based paint and varnish), surface treatment, and better construction methods are utilised to help prevent and combat these types of corrosion. The production technique of cements can be improved to prevent damage, too. Corrosion would usually be too late to remedy the problem once signs of damage occur on the surface. Hence, specialists rely on advanced testin

How to Use a Crack Measuring Device

Using a crack measuring device is one way to determine the overall integrity of a material like concrete. There different crack measuring devices are available to ensure proper measurement and accurate data collection. A good crack measuring device should be able to help you diagnose problems with concrete, so you can think of the most appropriate ways to remedy them. Here are ways to use some commonly used crack measuring devices : Digital position strain gauge deformation meter This device has a digital dial gauge attached to a bar. A conical point is fixed and mounted at one end of the bar, while the moving conical point is on a knife edge pivot on the other side. Pre-drilled stainless steel discs, are attached to the structure with an appropriate adhesive, are positioned using the setting bar. The gauge's conical points are inserted into holes in the discs when a reading is required, and the dial gauge's strain measurement is noted. This way, strain changes occu