A method and system for system for rapidly determining the predicted strength of concrete prior to pouring the concrete is disclosed herein. The system and process provides for a database storing concrete family characteristics that may be updated as actual strength of poured concrete is determined. The process also allows construction workers to pour concrete with a keener knowledge of the resulting concrete strength.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

A construction site mixing machine for mixing mixing materials contains a mixing container for a mixing material, a mixing tool displacement device, by which a mixing tool is displaceable between a mixing tool use position and a mixing tool non-use position. The mixing tool displacement device has a telescoping device or is formed by such a telescoping device. The mixing tool is displaceable by the telescoping device between the mixing tool use position and the mixing tool non-use position. According to an alternative concept, a control unit is configured to drive the mixing container by the mixing container drive unit in the opposite direction to the mixing tool which is drivable in rotation by the mixing tool drive unit and/or that the control unit has a timer function by which the operating time of the mixing tool drive unit and/or the mixing container drive unit is settable.

A device for producing a concrete includes a cement premixer for mixing a cement suspension, the cement premixer having an ultrasonic probe for preparing a cement suspension, a crystallization tank arrangement with the first crystallization tank, for increasing the early strengths of the concrete, and a concrete mixer for producing a concrete mixture from the premixed cement suspension, in particular with the addition of aggregates.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.