Particularities of chemical modifiers selection for fabricating concrete articles by extrusion technology

The purpose of the present work is developing the requirements for the chemical modifiers defining their suitability in extrusion technology for formation of articles from concrete and reinforced concrete. Experiment has been made by use of possibility of IK MGT to register synchronously the changes of pressure, volume and temperature at constant weight of the research sample. The research has shown that some substances such as paraffin and benzene at volume compression have phase transition from a liquid condition to the firm one. Taking into account the importance of phase transition of the first sort for the extrusion technology of concrete articles formation it is possible to confirm that substances which have the similar structural changes in testing range PVT parameters are not suitable for modifying of a concrete mix according to the given technology. Thus, according to the results of researches it is established that the olein acid is suitable for the extrusion technology of concrete formation. Use of engine oil 5W-50 is not effective because of its carcinogenic properties.