Some people call it an air pocket in the concrete or a void. It is the exposed course aggregates on surface of concrete without covered by mortar or surrounding the aggregate particles.
12. What is the purpose of the gap in the road on this bridge?
Purpose of the gap in the road is to allow the road to exPAnd and contract with temperature changes without causing damage or deformation to the road.
13. What is a projection line?
Projection line is the way, in which the earth is shown on a flat piece of Paper.
14. What are moment of inertia and its importance in civil engineering?
The moment of inertia measures the opposition any kind of body will have against a certain momentum (along that same axis) trying to rotate that body.
15. What is the absolute pressure scale?
Absolute pressure is calculated from a vacuum (0 PSI) and atmospheric pressure is14.7PSIa or 14.7 PSI above a vacuum 1PSI on a tire pressure gauge is called 1PSIg = 15.7PSIa 10PSIg=24.7PSIa 100PSIg=114.7PSIa etc.
16. What is diversion tunnel in a dam?
When a dam is to be built, a diversion tunnel is usually bored through solid rock next to the dam site to byPAss the dam construction site. The dam is built while the river flows through the diversion tunnel.
17. How do you maintain water pressure?
If you have water pressure and wish to maintain it, do not cause flow in the line, which will reduce pressure due to friction. To keep pressure up, reduce friction by increasing the line size or eliminating some other restriction.
18. What are some structures that may be subjected to fatigue?
Bridges, hydraulic presses, burners trains
19. Why does the pressure increase under soil?
Soil pressure increases with depth due to the overburden or self-weight of the soil and due to loads imposed upon the soil.
For example, the pressure variation below the depth of soil is linear and the relation is given by pressure = unit wt * depth. As depth increases, there will be a linear increase in the soil pressure.
20. What is the distance between railway tracks?
4 feet, 8 1/2 inches.