What does a gas-forming agent do when added to concrete?
What will be an ideal response?
Gas-forming agents are added to concrete or grout to cause a slight expansion in it before it hardens. Aluminum powder, one of several gas-forming agents in use, reacts with the hydroxides in hydrating cement and produces small hydrogen-gas bubbles. This also helps eliminate voids caused by settlement of the concrete or grout. A typical application consists of expanding the grout under a difficult-to-reach machine base or column to be certain the area is fully grouted. After concrete or grout has hardened, gas-forming agents will not overcome shrinkage. When they are used in large amounts, gas-forming agents produce lightweight cellular concrete.
You might also like to view...
____ for cast-in-place concrete may be constructed of lumber, plywood, aluminum, steel, and combinations of these materials.
A. Loadwork B. Form standards C. Formwork D. Form loads
On residential blueprints, ____________________ are used to provide the sizes and other pertinent information about the various doors and windows used in the building.
Fill in the blank(s) with the appropriate word(s).
The phases of a planned maintenance service call are:
A) Operational checks and troubleshooting. B) Routine maintenance, troubleshooting, and replacing parts that cause problems on many systems. C) Routine maintenance, pre-start inspection, operational checks, and troubleshooting. D) Routine maintenance and operational checks.
?A Sydney tube is often paired with a parabolic reflector fixed behind each tube.
Answer the following statement true (T) or false (F)