Fresh Properties and Mix Design for 3D-Printable Decorative Concrete

Постановка задачи. Рассмотрение закономерностей влияния вида цемента и модификаторов вязкости на технологические свойства смесей для 3D-печати определяется необходимостью одновременного обеспечения показателей пластичности и формоустойчивости смесей и декоративности композитов на их основе. Результаты. Представлены результтаты экспериментальных исследований основных реологических характеристик декоративного бетона для строительной 3D-печати. Выявлено влияние состава бетона на подвижность и формоустойчивость смеси. Установлено, что вид используемого цемента изменяет пластичность смеси и формоустойчивость под весом вышележащих слоев. Смеси с оптимальным компонентным составом декоративного бетона для строительной 3D-печати имеют следующие реологические характеристики: предел текучести K @ 1,0-2,2 кПа, структурная прочность s = 1,5-4,5 кПа, относительные пластические деформации Δ = 0,03-0,07 мм/мм. Данные характеристики определяют способность смеси к пластическому деформированию без разрушения структуры при течении, а также способность сохранять форму при печати слоя и нагружении вышележащими слоями. Выводы. Оптимальные диапазоны свойств смесей для 3D-печати могут быть изменены в 2-3 раза за счет использования цементов с различным гранулометрическим составом. Регулирование подвижности и формоустойчивости смесей с различными видами цемента главным образом обеспечивается применяемым модификатором вязкости. Statement of the problem. This paper present the rheological properties of 3D-printable decorative concrete. The effects of the mix proportion on its plasticity and shape stability are presented together. It has been established that a kind of cement changes the plasticity of fresh mixtures and its resistance to load during printing. Results. The fresh mixtures of 3D-printable decorative concrete with effective mix design had plastic yield value K @ 1.0-2.2 kPa, structural strength s = 1.5-4.5 kPa, value of plastic deformations Δ = 0.03-0.07 mm/mm. That has defined the ability of these mixes to plastically deform without any structure destruction and hold its shape, resist the deformation under compressions load during multi-layer casting. Conclusions. Shape stability of 3D-printable mix can be changed by 2-3 times by using cement with an efficient ranging of a particle size. The plasticity and shape stability of fresh mixes can be regulated using viscosity modifiers whose type depends on the type of cement.

FRESH PROPERTIES AND MIX DESIGN FOR 3D-PRINTABLE DECORATIVE CONCRETE

Statement of the problem. This paper present the rheological properties of 3D-printable decorative concrete. The effects of mix proportion on its plasticity and shape stability are presented together. It has been established that kind of cement changes plasticity of fresh mixtures and its resistance to load during the printing. Results. The fresh mixtures of 3D-printable decorative concrete with effective mix design had plastic yield value Ki 1.0 - 2.2 kPa, structural strength σ0 = 1.5 - 4.5 kPa, value of plastic deformations Δpl = 0.03 - 0.07 mm/mm. That is defined the ability of these mixtures to plastically deform without structure destruction and hold its shape, resist the deformation under compressions load during multi-layer casting.Conclusions. Shape stability of 3D-printable mixture can be changed by 2--3 times by using cement with efficient ranging of a particle size. The plasticity and shape stability of fresh mixtures can be regulated with usage of viscosity modifiers, the type of which depends on the type of cement.

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A SELF-DIRECTED METHOD FOR IMAGE SEGMENTATION USING A MODIFIED TOP-DOWN REGION DIVIDING APPROACH

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