Non Destructive Tests On Concrete
The characteristics of the operation of buildings and structures are determined by the strength, as well as by the bearing capacity of concrete structures that lie at the base. Therefore, the assessment of the condition of buildings for making a decision on repair or reconstruction includes checking the concrete for strength.
If it is necessary to assess the condition of reinforced concrete structures already in operation, a non-destructive method of concrete control is used, that is, work is carried out directly at the facility. Thus, it is possible to obtain information about the strength characteristics of the material without decommissioning the building, violation of the bearing capacity of the elements. Testing samples, engineers of LLP “Technical Control of building and construction safety” clearly follow the requirements of GOST, as well as SNIP. As a result, the customer receives a report on the safety margin of the structure.
Basic methods
Elastic rebound method
Plastic deformation
Shock pulse
Pull-Out Test
Separation with chipping
Chipping an edge
Factors that affect the accuracy of control:
—concrete composition
—property of aggregate
—changes occurring in the surface layers of concrete under the influence of carbon dioxide (carbonation);
—the conditions in which the solidification and setting of the material took place;
— age of the concrete structure
—parameters of temperature, surface humidity
Methods of local destruction of strength control are separation with chipping, rib chipping and separation of steel discs. This group of tests shows accurate results. Disadvantages: the surface of the object will be partially destroyed, before carrying out it is required to know the number and depth of the reinforcement.
— By applying separation with chipping, employees find out what the resistance of the material is when destroyed by the anchor device. However, such testing of anchors cannot be applied to thin-walled structures or densely reinforced areas.
— The use of the rib chipping method consists in chipping off the protruding corner. This method is suitable for testing linear structures. However, if the thickness of the protective layer of the material is less than 20 mm, the use of the method is unacceptable.
— A non-destructive testing method using steel discs requires gluing to the object 5-24 hours before the test, and then tearing off with fixing the results.
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Concrete control by impact is also common. It helps to assess the strength of the material, determine the class, elasticity, zones of heterogeneous structure or insufficient compaction. By acting on the surface, experts record the impact energy at the moment when the tool touches the structure. Information is entered into the accounting documentation after averaging the indicators of several strokes. The elastic rebound test method is used to determine not only the strength, but also the hardness of concrete.
Non—destructive strength testing with ultrasonic exposure is a study of the state of the “body” of the structure: the quality of concreting, size, depth of cracks, the presence of other defects. Special sensors are placed on 2 or 4 sides, and then surface or through sounding is performed. It should be noted that this method is unsuitable for testing high-strength concrete.
Contact the laboratory of LLP “Technical control of building and construction safety” — our staff will conduct the necessary tests efficiently and promptly with special equipment. We know exactly what types of concrete strength control are optimal in certain cases, are acceptable for use in the study of the object. The cost of services is transparent and profitable. You only need to place an order — the team of LLP “Technical security control of the building and structure” will cope with the solution of all other tasks perfectly.
Ultrasonic testing of concrete
Determination of the protective layer of concrete and the correct location of the reinforcement frame
Determination of the humidity of the structure –
Ultrasound examination of cracks in reinforced concrete structures
Determination of pile length, detection and localization of defects on the pile
In addition to non-destructive testing of concrete, LLP “Technical Control of Building and Construction Safety” conducts physical and mechanical tests of the properties of building materials
Concrete mixtures — determination of workability, medium density, porosity, delamination, water resistance
Concretes are heavy, light, cellular — Strength, abrasion, density, humidity, water absorption, porosity, frost resistance, water resistance, thermal conductivity.
Crushed stone and gravel from dense rocks for construction materials, sand for construction work, sand-gravel mixtures for construction work — Grain composition, the content of pulverized and clay particles, the content of grains of lamellar (bream) and needle forms, the content of grains of weak rocks, bulk density and voidness, crushing, frost resistance, water absorption.
Portland cement and slag—Portland cement – Fineness of grinding, consistency. Normal density, setting time, uniformity of volume change, strength
Construction solutions — Mobility. Density, delamination, water-holding capacity, strength, average density, humidity, water absorption, frost resistance.
Кирпич и камни керамические силикатные — Прочность, средняя плотность. Водопоглощение, морозостойкость
Ceramic silicate stones and bricks— Strength, average density. Water absorption, frost resistance
Precast reinforced concrete structures and products — Geometric measurements, thermal conductivity, thickness of the protective layer, strength, rigidity, crack resistance
