There are miscellaneous testing available for execution depending on the plausible root cause or critical issues. There are three types of test which Oreads Buildingcare can conduct for hardened concrete, namely; in-situ destructive test, in-situ non-destructive test and laboratory test. Our lab and our associate labs are open to the idea of assisting academicians in their research and contractors or builders mainly in material submission, concrete design by prescribing design mix, conducting trial mix and other scope of works. For such testing, we have our test equipment for compacting factor, vebe time, determination of air content, density, and et cetera for cubes, cylinders and beams. Besides concrete, we are able to conduct flow-through test for grout and shotcrete as well as determining aggregate properties test. We have local and international associates who can assist shall there be a need for additional test which is not mentioned here or not commonly available in the market.
Chemical Laboratory Test
For hardened concrete, the followings are the usual test which we are able to conduct with the assistance of lab technicians and a resident professional geologist.
Carbonation Depth Test
In order to check the chemical condition in the concrete, phenolphthalein will be sprayed at the fresh cored sample. The depth of the carbonation is indicated by the distance and depth covered by pink color after applying phenolphthalein.
Concrete Coring and Compressive Strength Test
Coring shall be in accordance to BS EN 12504-1, Testing Concrete in Structure – Cored Specimens – Taking, examining and testing in compression. In case of any structural members is having relatively intimate reinforcement nominal links, the compressive strength shall be acquired by other method and to be correlated accordingly.
Concrete Hacking Test
Concrete Hacking is a destructive test which shall be performed in order to evaluate the condition of the concrete and the reinforced steel bars in the said location. Aside from that, this will also provide the actual reinforcement bars’ size and number as well as spacing to be tallied to any indicative as-built drawing to form the steel (bending) schedule.
Electromagnetic Covermeter Test
This test method is deployed in order to check the thickness of concrete structure cover by determining the distance between the surface and the reinforcement bars. Aside from that, this test will ensure coring work to acquire samples will not affect the structure’s reinforcement bars. This method is specified in BS1881-204:1986, Testing Concrete – Recommendations on the use of electromagnetic covermeters.
Half-Cell Potential Test
Half-Cell Potential is a non-destructive test which shall be performed to measure the surface potential which is associated with corrosion current. This method is described in BS1881-201:1986, Testing Concrete – The Guide to the use of non-destructive methods of test for hardened concrete; Section 2.4 or may be executed in accordance to ASTM C876-80 Standard Test Method for Half-Cell Potential of Reinforced Steel in Concrete.
Rebound Hammer Test
The main method in acquiring the strength of the concrete at site is by using Rebound Hammer method at selected areas of the building and to be correlated to the Cored Samples. This method is described in BS EN 12504 Part 2.
Ultrasonic Pulse Velocity
This test allows measurement to be made based on the velocity of the ultrasonic pulse which can determine uniformity of the concrete, detection of cracks and determine the modulus of elasticity of the sample. Test shall be conducted based on BS1881-203:1986, Testing Concrete – Recommendations for measurement of velocity of Ultrasonic Pulses in Concrete or BS EN 12504 Part 4.
Chloride Content Test
Quantab Test Strip or Laboratory test would identify the level of chloride content and/or ingress into the concrete as well as a measure to check if chloride ions are passive inhibitor in the concrete structure. Apart from that, this test shall be conducted in accordance to BS1881-124:1988.
Pull-off and Pull Out Test
Pull-off and Pull Out test are available in order to determine two different parameters. Pull Out test is based on BS EN 12504-3:2005 Testing concrete in structures. Determination of pull-out force standard requirement to establish the load capacity strength of fixings that have been installed or fitted into walls, slabs, soffits et ceteras by measuring the force required to pull an embedded metal insert and the attached concrete fragment from a concrete mass. Pull-off on the other hand will be based on BS EN 1542:1999 Products and systems for the protection and repair of concrete structures. Test methods. Measurement of bond strength by pull-off.
Petrography Examination is a non-destructive test which shall be performed by utilizing concrete cores extracted at selected areas. through Scanning Electron Microscope (SEM). This method is described in BS1881-211:1986, Testing Concrete – Procedure and Terminology for the petrographic examination of hardened concrete, or/as per ASTM C856-04, Standard Practice for Petrographic Examination of Hardened Concrete.
X-ray Diffraction Analysis
This is a method used in materials science to determine the crystallographic structure of a material. XRD works by irradiating a material with incident X-rays and then measuring the intensities and scattering angles of the X-rays that leave the material. It is mainly for elements tracing which involve structural properties such as lattice parameters, strain, grain size, epitaxy, phase composition and preferred orientation. This allows determination components of concrete and/or geotechical and geological materials.
Electrical Resistivity Tomography
When typical Site Investigation works involving laboratory and field test are not comprehensive enough in rendering the actual geological and geotechnical condition for deep ground mainly in dam and foundation works, Electrical Resistivity Tomography (ERT) will be the best option to compliment findings of these tests. It is a geophysical test which provides sub-structure sectional imaging where electrodes or probes are placed within in a parallel order to define the properties of the sub-surface and deep strata.