| Pozzolan (ASTM C 618) | (Concrete Engineering) A siliceous, or siliceous and aluminous material, which in itself possesses little or no cementitious value but will, in a finely divided form, such as a powder or liquid and in the presence of moisture, chemically react with calcium hydroxide at ordinary temperatures to form permanent, insoluble compounds possessing cementitious properties. |
| Rebound | (Concrete Engineering) Wet shotcrete or sand and cement which bounces away from a surface again at which pneumatically applied mortar is being projected. |
| Rod (tamping) (ASTM C24l) | (Concrete Engineering) A round, straight steel rod, 5/8' in diameter and approximately 24' in length, having the tamping end rounded into a hemispherical tip, the diameter of which is 5/8'. |
| Transit-Mixed Concrete | (Concrete Engineering) Concrete produced from a central-batching plant, where the materials are proportioned and placed in truck-mixers for mixing enroute to the job or after arrival there. |
| Vaporproof | (Concrete Engineering) A material that is totally immune to the passage of a gas under pressure. Any material that is truly vaporproof will inherently be waterproof. |
| Vibration | (Concrete Engineering) Energetic agitation of concrete to assist in its consolidation, produced by mechanical oscillating devices at moderately high frequencies. (A.) External vibration employs a device attached to the forms and is particularly applicable to the manufacture of precast items and for the vibration of tunnel lining forms. (B.) Internal vibration employs an element which can be inserted into the concrete; and is more generally used for cast-in-place construction. |
| Wagner Fineness | (Concrete Engineering) The fineness of materials such as portland cement expressed as total surface area in centimeters per gram as determined by the Wagner turbidimeter apparatus and procedure. |
| approach light | แสงสว่างที่นำทางให้เครื่องบินลงทางวิ่งได้ถูกต้อง |
| approach zone | บริเวณหรือเขตก่อนถึงทางวิ่งของเครื่องบิน ซึ่งจะต้องไม้มีสิ่งกรีดขวางการขึ้นลงของเครื่องบิน |
| damp proof course | แผ่นกันชื้น, แผ่นวัสดุบรรจุไว้ภายในผิวก่อสร้างเพื่อกันชื้น |