Вестник Брестского государственного технического университета
https://rep.bstu.by/handle/data/19557
2024-03-29T10:41:48ZMicrostructure development of the cement paste based on the unit cell mode
https://rep.bstu.by/handle/data/40741
Microstructure development of the cement paste based on the unit cell mode
Kravchenko, Valentin Viktorovich
Microstructure development of the cement paste is closely associated with internal processes such as self-desiccation, shrinkage, creep and other internal processes throughout service life of cement-based materials. The ability to accurately model microstructure parameters is key to predicting internal processes of the cement paste. Currently, the most frequently used approaches to microstructural modeling of cement paste are vector and discrete. Both approaches generate and process a random structure of the cement paste, but at the same time are characterized by high computational complexity and time-consuming. It accounts for the fact, that simplified structural models still remain relevant. A unit cell model, which can be considered as a particular case of the vector approach, is a geometrically simple model that describes microstructure development based on a representative hydrated cement particle. The paper presents an advanced microstructural model of the cement paste based on the unit cell model.
Кравченко В. В. Моделирование микроструктуры цементного камня на основе модели элементарной ячейки.
2023-01-01T00:00:00ZAssessment of uncertainty model of restrained expansion strains of fiber reinforced self-stressing concrete at the expansion stage
https://rep.bstu.by/handle/data/40740
Assessment of uncertainty model of restrained expansion strains of fiber reinforced self-stressing concrete at the expansion stage
Paulava, Inessa Pavlovna; Belkina, Irina Vladimirovna; Lizahub, Aleksandr Aleksandrovich
The article presents an analysis of existing approaches to predicting the self-strains and stresses of self-stressing concrete. The main premises and equations of the modified strains development model for determining the self-strains and stresses of fiber reinforced self-stressing concrete at the expansion stage. This mutual influence model constrains the elements in three directions. The presented model was verified against the background of experimental data. An assessment of the model uncertainties of the modified strains development model of fiber reinforced self-stressing concrete on the 3rd, 7th, 14th and 28th day of concrete age is estimated. The developed model is applicable for any composition of self-stressing concrete, as well as for various combinations of dispersed reinforcement.
Павлова И. П., Белкина И. В., Лизогуб А. А. Оценка ошибки моделирования собственных деформаций напрягающего фибробетона на стадии расширения
2023-01-01T00:00:00ZAnalysis of calculation methods and numerical simulation of the stress-strain state of reinforced concrete elements under local action of tensile forces
https://rep.bstu.by/handle/data/40739
Analysis of calculation methods and numerical simulation of the stress-strain state of reinforced concrete elements under local action of tensile forces
Shalobyta, Nikolay Nikolaevich; Matveenko, Elizaveta Sergeevna; Matveenko, Nikifor Viktorovich; Rakhuba, Valery Ivanovich
The analysis of methods for calculating the loadbearing capacity of reinforced concrete elements for tearing, given in the domestic technical literature, as well as in the literature countries of near and far abroad, has been conducted. A numerical study of the stress-strain state of the tearing zone under the local action of tensile forces was carried out.
Шалобыта Н. Н., Матвеенко Е. С., Матвеенко Н. В., Рахуба В. И. Анализ методов расчета и численное моделирование напряженно-деформированного состояния железобетонных элементов при местном действии растягивающих усилий
2023-01-01T00:00:00ZLightweight concrete based on bio-aggregates and gypsum binder for construction products
https://rep.bstu.by/handle/data/40737
Lightweight concrete based on bio-aggregates and gypsum binder for construction products
Parfenova, Lyudmila Mikhailovna; Matskevich, I. D.; Tolmach, М. P.
Selecting the optimal composition of gypsum concrete with a two-component organic aggregate and glass fiber is a complex task, which in this work was solved using desing of experiment. Adequate mathematical models of tensile strength in bending, compressive strength and water absorption are determined. Based on the mathematical planning of the experiment, the composition of gypsum concrete with the maximum value of tensile strength in bending, which is used in the manufacture of gypsum concrete slabs, was determined. It is shown that gypsum concrete slabs made using casting technology from the developed gypsum concrete composition have a thermal conductivity coefficient K = 0,256 W/(m·K) and provide a noise level reduction to 29,55 dB in the frequency range from 100 to 300 Hz.
Парфенова Л. М., Мацкевич Я. Д., Толмач М. П. Легкие бетоны на основе биозаполнителей и гипсового вяжущего для изделий строительного назначения
2023-01-01T00:00:00Z