RESEARCH OF THE STRESS STATE OF A MODIFIED IN-SITU CONCRETE
Journal Title: Наука та прогрес транспорту - Year 2016, Vol 0, Issue 6
Abstract
Purpose. The article focuses on investigation of the stress state of a modified in-situ concrete of natural hardening. Methodology. To achieve the aim, the research of the microstructure of the modified cement matrix of concrete, as well as the mechanism of structure formation of modified concrete with natural hardening was conducted; the methods for reliable evaluation of concrete strength were defined. Findings. The development of internal stresses affects the properties of concretedifferently. With an increase in temperature-shrinkage deformations in time and, thus, with increasing structural stresses in the cement sheath around the grains of the filler two opposite processes may develop: zone of plastic flow or cracking. Originality. It was established that the structural features complex of the modified concrete when the load transfer leads to the formation of extensive zones of prefracture which is able to absorb a significant amount of elastic strain energy that provides the design deformation properties of the concrete for special purposes. Ideas about the definition of the criteria of cracking modified concrete, hardening under natural conditions had further development. Practical value. The resulting equations allow to solve the problem about the minimum level of structural stress in monolithic concrete in a saturated large placeholder, as well as to assess the influence of structural stresses on the properties of concrete. In normal concrete with a relatively thin cement sheath at temperature-shrinkage deformations, high tangential and low radial tension occur. In vivo, this stress is higher as a result of higher values of Δε(τ), which is not observed in the modified concrete. In the modified concretes only tangential stresses are the greatest danger to structures. The change of shrinkage stress with time is straightforward. The total temperature-shrinkage deformations have a sawtooth graph. For modified concrete the amplitude is 48…53% less. This will allow solving a number of technological challenges in the construction of monolithic buildings.
Authors and Affiliations
D. V. Rudenko
Keywords
Related Articles
- EP ID EP226892
- DOI 10.15802/stp2016/90515
- Views 106
- Downloads 0
ЕНЕРГОЗБЕРЕЖЕННЯ ПРИ ЕКСПЛУАТАЦІЇ В ЛОКОМОТИВНИХ ДЕПО ПРИСТРОЇВ ІЗ НЕРЕГУЛЬОВАНИМ ЕЛЕКТРОПРИВОДОМ
Мета. У роботі необхідно провести дослідження електричних двигунів для отримання результатів, які дозволять оцінити ступінь енергозбереження за рахунок зменшення електричних витрат у пристроях із нерегульованим електропр...
RESEARCH PREMATURE DESTRUCTION OF CONCRETE SLEEPERS ON THE MAIN LINES OF PUBLIC COMPANY «UZ»
Purpose. The study aims to identify the causes of premature destruction of concrete sleepers of one of Ukrainian producers. Methodology. Applied microstructural, fractographic, X-ray microanalysis revealed causes of tran...
REDUCTION IN CUTS SPEED AT THE BEGINNING OF A SORTING SIDINGS, EQUIPPED WITH QUASI-CONTINUOUS SPEED CONTROL SYSTEM
Purpose. Clear and uninterrupted operation of humps depends on the quality of technical equipment and control technology of cuts speed. Technology of interval and purposive regulation of cuts speed is used at most humps....
ПРОЕКТУВАННЯ РОЗГОРТНИХ ПОВЕРХОНЬ ДЕТАЛЕЙ СКЛАДНОЇ ФОРМИ
Мета. У статті необхідно розглянути забезпечення раціонального вибору параметрів поверхонь, що сполучаються, та оброблюваних деталей при проектуванні технологічного обладнання на основі методів штучного інтелекту. Методи...
СОВЕРШЕНСТВОВАНИЕ ТЕХНОЛОГИИ РАБОТЫ БЕЛОРУССКОЙ ЖЕЛЕЗНОЙ ДОРОГИ В УСЛОВИЯХ ПРИМЕНЕНИЯ ЭЛЕКТРОННЫХ ДОКУМЕНТОВ
Цель. В научной работе необходимо рассмотреть совершенствование технологии работы железнодорожного транспорта общего пользования Республики Беларусь в условиях применения электронных юридически значимых документов. Метод...