INSPECTION & TESTING
Inspection and testing of concrete structures BEFORE beginning work is an often overlooked step, providing crucial information about the state of your concrete structure. External signs like spalling, cracks, and efflorescence may be symptoms of deeper underlying problems, invisible to the naked eye. An informed and accurate diagnosis of your substrate is vital to when embarking upon repairs and/or waterproofing of your concrete structure.
Basecrete Technologies LLC can help you by properly diagnosing the true hidden issues that need to be addressed through a wide range of comprehensive tests carried out by qualified engineers using modern diagnostic equipment.
Our range of services and tests include:
• On-site visual inspection before the application of Basecrete waterproofing
• Corrosion Testing
• Concrete Damage Evaluation using ground penetrating radar
• Coatings testing
• Rapid Chloride Permeability of concrete
• Sound (noise) measurement
On-site visual inspection is available free of charge to all existing Basecrete customers. Simply call us and schedule an appointment and we will carry out an inspection advising you of the best procedure to follow for either waterproofing your suspended pool or repairing your concrete. We will also advise you if we believe further testing is recommended.
Corrosion is an electrical-chemical process. As such, the corrosion activity of rebars in concrete produces local batteries. The strength of the battery is indicative of the severity of corrosion.
Measurement of electrical activity at the rebar-concrete interface and its mapping over the surface area of concern is far more informative than hammer-tapping. In a structure older than 15 years, even a good sounding concrete may have active rebar corrosion underway. A snapshot of corrosion activity within the concrete structure can help in deciding protection strategies. It also helps reliably estimate the repair quantities.
The corrosion status is typically tested in two ways. First, measuring corrosion potential of corroding metal indicates the level of severity of corrosion (ASTM C876), and second, corrosion rate, which signifies the aggressiveness of the environment in advancing the corrosion.
However, this type of testing requires sophisticated equipment as well as experience.
SRI employs CANIN® Potential mapping instrument, State-of-the-Art Gamry G750 and Ivium Pocket STAT Potentiostatt/Galvanostat, and Nilsson 400 Resistivity Meter for comprehensive corrosion tests.
4-Pin Resistivity Meter
CANIN by Proceq
GROUND PENETRATING RADAR (GPR)
FOR CONCRETE DAMAGE EVALUATION
Compared to hammer-tapping, GPR is far superior in evaluating condition of concrete in a structure. Importantly, it can be used over tiles and other surface covering. Typically, GPR provides:
• Location and depth of reinforcing steel.
• Locations of high moisture content indicative of delamination / cracking.
• Location of subsurface voids.
• Location of other embedded metallic objects such as post-tensioned cables and live electrical conduits.
• Estimation of extent of damage or repair quantities.
• Evaluation of concrete to a depth of ~12”-18”.
• Graphical record of the structure’s cross section.
• Reproducible of the results.
GPR scans conducted over different periods can help estimate the damage progress and repair frequency. SRI has two GPRs. GSSI Miniscan 3D, a portable 1GhZ, all-in-one machine and Mala CX11 with 1.2 GHz antenna and capability to sense live electrical conduits and use interchangeable antenna.
GSSI MiniScan 3D GPR
Reinforced Concrete Slab Scan
Mala CX11 GPR
Coatings such as paint, protective chemicals or spray applied sacrificial zinc are often in need of QA/QC testing, remaining life determination or adhesion. Coatings substrate can be metallic or non-metallic.
Depending upon the substrate and QA/QC requirements, several instruments are used in testing:
• Positector 6000 - measures thickness of coatings on metallic surfaces
• Paint Inspection Gage IV measures thickness of paint layers applied to concrete or wood substrates
• High precision Mitutoyo Digimatic Micrometer IP65 is used for any coating sample removed from the substrate
• Elcometer tests adhesion of coatings to any substrate, although it requires elaborate test preparation.
RAPID Chloride Permeability & SOUND (NOISE) MEASUREMENT
Rapid Chloride Permeability of Concrete
Durability of concrete to chloride diffusion is of great interest, especially in coastal environments, since presence of chlorides in concrete creates aggressive corrosive environment. Whether it is a existing or a new concrete structure, chloride diffusion coefficient is predictive of remaining service life or durability-based design. It is also important in testing effectiveness of various coatings to minimize or prevent chloride diffusion. ASTM C1202, ASTM C1760 and ASTM C1556 are some of the widely used standards. Perma2 by Giatec Scientific can perform several chloride diffusion related tests according to these ASTM standards.
Sound (noise) Measurement
Noisy equipment such as generators, air handlers are not only nuisance but often times violate local ordinances leading to neighborly disputes. A survey involving sound measurements is useful in
• Detecting source of noise
• Detecting noise patterns
• Designing sound-proofing
SRI’s Digital Sound Meter 8922 is capable of measuring sounds in the range of 30-130 dB (decibles).