Borescopes are used to perform a type of visual inspection n buildings and confined spaces and mostly used in non destructive testing techniques for recognizing defects or imperfections.
Carbonation testing & Concrete Cancer
Carbonation of concrete occurs when the carbon dioxide, in the atmosphere in the presence of moisture, reacts with hydrated cement minerals to produce carbonates, e.g. calcium carbonate.
The carbonation process is also called depassivation. Carbonation penetrates below the exposed surface of concrete extremely slowly. Carbonation is significant as it neutralizes the alkalinity present in the concrete.
Thus, if it reaches the reinforcements it makes them more susceptible to corrosion. Commonly termed as concrete cancer.
Used mostly by the Construction Industry to provide access through masonry walls and floors for plumbing and electrical services.
Concrete Coring is also used to make holes for starter bars in existing concrete slabs or walls. Concrete Coring is also utilised to gain access to materials through concrete slabs, pavements or through existing concrete piers to depths of up to 8 metres and deeper with notice.
Testing is conducted in general to ascertain the condition of the concrete.
In our line of work a core sample is a cylindrical section of (usually) rock or concrete. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called a core drill.
This can then be inspected and analysed by different techniques and equipment depending on the type of data desired.
Corrosion Mapping Ultrasonics
Corrosion mapping by ultrasonics is a non intrusive (non invasive) technique which maps material thickness using ultrasonic techniques. Variations in material thickness due to corrosion can be identified and graphically portrayed as an image.
The technique is widely used in the oil and gas industries for the in-service detection and characterization of corrosion in pipes and vessels.
Cover Meter Surveys/Ferro Scan
A cover meter is an instrument to locate rebars (in layman’s terms rebar is the steel that holds and reinforces the concrete of a building) and measure the exact concrete cover. Rebar detectors are less sophisticated devices that can only locate metallic objects below the surface. Due to the cost-effective design, the pulse-induction method is one of the most commonly used solutions.
Engineering consultants, who contract Specialist Height Access to cure the problem of concrete cancer and rebar corrosion, generally complete this inspection though SHA often assist.
Dye Penetrant Surface Techniques
Traditionally Dye penetrant may be applied to all non-ferrous materials and ferrous materials, although for ferrous components magnetic-particle inspection is often used instead for its subsurface detection capability.
Liquid Penetrant (LP) is used to detect casting, forging and welding surface defects such as hairline cracks, surface porosity, leaks in new products, and fatigue cracks on in-service components.
Low cost method though surface tested should preferably be smooth. However there are steps to follow when applying the techniques we use, which can cater for any imperfections.
Eddy Current Testing
Eddy Current Inspection is an electromagnetic technique used for conductive materials to detect surface and near surface defects. This inspection method is sensitive to small cracks and other flaws. It is used to inspect parts of complex shape and size, gives immediate results and is widely used within the commercial, military, petrochemical, aircraft and aerospace industries.
Ferro Scan/Cover Meter Surveys
A cover meter is an instrument to locate rebars and measure the exact concrete cover. Rebar detectors are less sophisticated devices that can only locate metallic objects below the surface. Due to the cost-effective design, the pulse-induction method is one of the most commonly used solutions.
Guided Ultrasonic Techniques
This is especially cost effective in difficult to access locations. Guided Ultrasonic waves provide a great solution for pipe inspection.
The inspection is a very fast screening technique which provides information about cross section area change in a pipe together with precise information as to where the change occurs.
Half Cell Testing
The half-cell testing method is used to determine if the reinforcing steel is under active corrosion. This method utilizes a multimeter to measure the potential difference between the steel and a half-cell apparatus.
The analysis of the potential difference can indicate if active corrosion is taking place on the reinforcing steel.
Ideal for fast, inexpensive, nondestructive estimations of in-place concrete strength.