Chapter 16 - Test Instruments For Coating Concrete

Question 1

What institute produces a set of comparator plates for various surface of prepared concrete?

Answer 1

ICRI - International concrete repair institute

Question 2

DFT of coating on concrete can be measured by?

Answer 2

Estimated from WFT
Estimated from quantity of coating used
Verified by a paint inspection gauge (tooke)
Determined by a modified gauge based on ultrasound

Question 3

List standards that may be used for dry film measurement of coatings over concrete?

Answer 3

ASTM-D6132-97 Standard test method for nondestructive measurement of dry film thickness of applied organic coating over concrete using an ultrasonic gage

SSPC -PA9 measurement of dry coating thickness on cementitious Substrates

Question 4

Describe the proper safe accurate operating procedure for a low voltage holiday detector.

Answer 4

Ground cable is attached directly to substrate
Sponge saturated with a solution of a tap water/wetting agent
Maximum rate of 30cm/s (1 linear ft/s) double stroke
Used on coatings up to 500um (20mils)
May be used on concrete

Question 5

How is the ASTM D 4263, standard test method for indicating moisture in concrete by the plastic sheet method used?

Answer 5

A segment of a 1.0mm (4.0mil) thick, clear polyethylene sheet approximately 457x457mm (18x18 in) is taped over the concrete to be tested so that the concrete is tightly sealed from the atmosphere and sunlight. The test patch is allowed to remain a minimum of 16hours.