| Plane of Weakness | (Concrete Engineering) The plane along which a structure under stress will tend to fracture; may exist because of the nature of the structure and its loading, by accident, or by design. |
| Plastic | (Concrete Engineering) A condition of freshly mixed concrete. mortar or cement -paste indicating that it is workable and readily re-moldable, is cohesive, and has an ample content of fines and cement but is not over wet. |
| Portland Blast- slag Cement Furnace (ASTM C 595) | (Concrete Engineering) The product obtained by intimately intergrinding or an intimate and uniform blending a mixture of granulated blast furnace slag and portland-cement clinker |
| Portland Cement (ASTM C 150) | (Concrete Engineering) The product obtained by pulverizing clinker consisting essentially of hydraulic calcium silicates. |
| Portland-Pozzolan Cement (ASTM C 595) | (Concrete Engineering) The product obtained by intimately intergrinding a mixture of portland-cement clinker and pozzolan, or an intimate and uniform blend of portland cement and fine pozzolan. |
| Pumping (of Pavements) | (Concrete Engineering) The ejection of a mixture of water and solid materials such as clay or silt along cracks, transverse or longitudinal joints, and along pavement edges caused by downward slab movement due to the passage of heavy loads, machinery or equipment over the pavement after free water has accumulated in or on the subbase, subgrade or basecourse. |
| Revibration | (Concrete Engineering) Delayed vibration of concrete that has already been placed and consolidated. Most effective when done at the latest time a running vibrator will sink of its own weight into the concrete and make it plastic and workable again. |
| Rock Pocket | (Concrete Engineering) Area or portion of hardened concrete which is deficient in mortar and consisting primarily of coarse aggregate and open voids; caused by insufficient consolidation or separation during placement, or both; by leakage from form. |
| Sack | (Concrete Engineering) A quantity of cement: 94 Ibs. in the United States, 87.5 Ibs. in Canada, for portland or air entraining portland cement, or as indicated on the sack for other kinds of cement. |
| Sacking | (Concrete Engineering) Removing or alleviating defects on a concrete surface by applying a mixture of sand and cement to the moistened surface and rubbing with a coarse material such as burlap. |