Concrete – a composite mixture of water, aggregates, cement and sometimes additives – is an essential material in the construction and building industry, used across a number of different applications in the residential, industrial, commercial and maritime sectors.
Concrete brings structural rigidity to structures, and consequently, the quality of concrete is crucial if structures are to be safe and serve the purpose for which they were designed.
Importance of Testing
Consequently, the testing of fresh, hardened and in-situ concrete is vital to ensure that concrete structures comply with specifications and relevant standards.
ELE International designs and manufactures a comprehensive range of concrete sampling and testing equipment to meet this requirement in accordance with international standards for both field and laboratory testing.
With high compressive strength and low tensile strength, concrete is usually reinforced with materials such as steel. However, different strengths of concrete are used for different applications.
Lightweight, low-strength concrete has good thermal properties and is suitable for sub-screeds and filling redundant voids, whereas high strength concrete is generally specified in large projects, for example in lower floor columns of high-rise concrete buildings and in bridge beams.
ELE’s concrete testing equipment is designed to ensure that these different types of concrete can be tested to ensure that they meet the specific requirements of each project.
How is Concrete Tested?
Fresh concrete is tested onsite and in the laboratory using the slump cone test and air entrainment meters to check the water-cement ratio, air content and workability.
It may also be necessary to measure compaction and density, drying, shrinkage and moisture movement. To demonstrate compliance with specifications, concrete specimens are taken and prepared in moulds as cubes, cylinders or beams.
Fresh and Hardened Concrete Testing
ELE’s testing equipment includes a range of curing tanks, fitted with a submersible pump, immersion heater/thermostat unit and separate control panel, as well as a lower rack as standard and is designed to maintain the temperature at 20°C.
Compression Testing Machines
Typically concrete cubes are cured and tested in a manual or automatic concrete compression machine at 7 days and 28 days to assess compressive strength. ELE’s comprehensive range of concrete compression machines is able to test concrete, mortar and cement samples such as cubes, cylinders, flagstones and beams.
ELE also has accessories for testing the flexural and transverse strength of concrete samples, including beams.
Non-destructive Testing
Concrete cores can be taken from hardened concrete for testing, but Non-destructive Test (NDT) equipment enables the testing of in-situ concrete or concrete samples. ELE provides crack detection microscopes, and a (Schmidt) rebound hammer, or test hammer, for measuring surface hardness and penetration resistance.
Our NDT testing equipment also includes Ultrasonic Detection for internal condition testing, Rebar Detection, Pull-Off Testing, Pulse Velocity and in-situ water Permeability testing devices.