The possibility of using expanded perlite dust (RUNWAY) in cement binder systems is being considered. A method for modifying the binder by joint mechanical activation of Portland cement, alumosilicate waste and hyperplasticizer is presented. The physico-chemical features of the modified runway make it possible to regulate the processes of hydration, phase formation, as well as the formation of the structural matrix of the composite. The compressive strength of the binder using RUNWAY as an active mineral additive increases by 36% with a decrease in density.
Keywords: technogenic raw materials, perlite, binder, dispersion, modification, mechanical activation, hydration, structure formation, phase formation, resource conservation
The factors affecting the strength of the interlayer bond of 3D concrete, as well as factors affecting the ability of the printer nozzle to produce a controlled concrete thread of a particular composition, which is being investigated in the process of 3D printing technology, the main characteristics of the suitability of compositions for printing on a 3D printer, requirements for rheology, hydration and strength in an uncured form, are considered 3D concrete, the main mechanical test methods for determining the adhesion strength in concrete printed on a 3D printer. The possible shapes and nominal sizes of the samples used in the methods for determining the strength of concrete are given.
Keywords: 3D concrete, anisotropy of mechanical properties, extrusion, cold connection, interfacial coupling, deflocation, thixotropy, initial static viscosity, curing, three-point bending