| Condensation | (Concrete Engineering) When a moisture laden gas comes in contact with a cooler surface a change of state from gaseous to liquid occurs. |
| Elastic Shortening | (Concrete Engineering) The shortening of a member in pre-stressed concrete which occurs on the application of forces induced by prestressing. |
| Entrained Air (See air entrainment) | (Concrete Engineering) Microscopic air bubbles intentionally incorporated in mortar or concrete, to improve workability and durability (usually imparting a higher degree of resistance to freezing and thawing). |
| Entrapped Air | (Concrete Engineering) Air in concrete which is not purposely en-trained, Entrapped air bubbles are normally much larger and more irregular than entrained air bubbles. |
| Gillmore Needle | (Concrete Engineering) A device used in determining time of setting of hydraulic cement, described in ASTM 0 266. Gradation The sizing of granular materials; for concrete materials, usually expressed in terms of cumulative percentages larger or smaller than each of a series of sieve openings or the percentages between certain ranges of sieve openings. |
| Hydrogenesis | (Concrete Engineering) Another term for condensation. The term is especially applied to base and soil substrates under highway pavements. where the barometric pump causes the inhalation of humid air, which then condenses in those structures, causing an ever increasing moisture content and sometimes instability. |
| Hydrologic Cycle | (Concrete Engineering) The Hydrologic Cycle consists of the evaporation of water from oceans and other bodies of open water; condensation to produce cloud formations; precipitation of rain, snow, sleet or hail upon land surfaces; dissipation of rain or melted solids by direct run-off into lakes and by seepage into the soil. Thereby producing a continuing endless source of water in the sub-grade. |
| Impermeable | (Concrete Engineering) The ability of a material or product to reduce or eliminate gaseous transmissions through it's mass; measured as the rate of Water Vapor Transmission (WVT). Note: Not all materials that are waterproof are vaporproof; all materials that are vaporproof are inherently waterproof. |
| Jacking Equipment | (Concrete Engineering) In prestress concrete, the device used to stress the tendons. |
| Keene's Cement | (Concrete Engineering) A finely ground high density plaster composed of anhydrous, (calcined or "dead burned") gypsum, the set of which is accelerated by the addition of other materials. |