| Bleeding, Bleed Water | (Concrete Engineering) A form of segregation in which some of the water in a mix tends to rise to the surface of freshly placed concrete. Known also as water gain. |
| Bush-hammer | (Concrete Engineering) A tool having a serrated face, as rows of pyramidal points, used to develop an architectural finish for concrete surfaces. |
| Calcine | (Concrete Engineering) To alter composition or physical state by heating to a specific temperature for a specific length of time. |
| Cellular Concrete | (Concrete Engineering) A lightweight product consisting of portland cement, cement-pozzolan, cement sand, lime-pozzolan, or lime-sand pastes, or pastes containing blends of these ingredients and having a homogenous void or cell structure, attained with gas forming chemicals or foaming agents. For cellular concretes, containing binder ingredients other than or in addition to portland cement, autoclave curing is usually employed. |
| Cement, Portland (ASTM C150) (Concrete Engineering) | A powdery substance made by burning, at a high temperature, a mixture of clay and limestone producing lumps called “clinkers” which are ground into a fine powder consisting of hydraulic calcium silicates. For non-portland cements, see aluminous cement. |
| Chair(s) | (Concrete Engineering) In concrete formwork, the support for the reinforcing steel. |
| Change of State | (Concrete Engineering) The process whereby liquid is heated to the point of evaporation changing the liquid into a gas the condensation of a gas on a cooler surface returning it from gaseous to liquid form. |
| Cold Joint | (Concrete Engineering) A visible lineation which forms when the placement of concrete is delayed. The concrete in place hardens prior to the next placement of concrete against it. |
| Consistency | (Concrete Engineering) The degree of plasticity of fresh concrete or mortar The normal measure of consistency is slump for concrete and flow for mortar. |
| Consolidation - | (Concrete Engineering) Compaction usually accomplished by vibration of newly placed concrete to minimum practical volume, to mold it within form shapes and around embedded parts and reinforcement, and to eliminate voids other than entrained air. |