Оцінювання напружень від усадки в цементобетонному покритті автомобільних доріг
Date
2019-02-26
Journal Title
Journal ISSN
Volume Title
Publisher
Видавництво Львівської політехніки
Abstract
Запропоновано математичне розв’язання визначення напружень усадки в
цементобетонному покритті автомобільних доріг. Об’єкт дослідження – напруження
усадки у цементобетонному покритті з кристалізаційною структурою при тужавінні та
твердненні. Мета роботи полягає у виведенні математичної залежності, яка моделює та
дає можливість оцінити розподіл напружень усадки, що виникають у цементобетонному
покритті. Метод дослідження – аналітичний метод визначення напружень усадки в
цементобетонному покритті з використанням положень теорії пружності. На основі
теоретичного рішення виведено математичну залежність, яка моделює та дає
можливість оцінити розподіл напружень усадки, що виникають у цементобетонному
покритті з кристалізаційною структурою при тужавінні та твердненні. Отримане
рішення дасть змогу уточнити розрахунки довговічності цементобетонного шару
дорожнього одягу з кристалізаційною структурою.
The mathematical solution for determining the contraction stresses in the cementconcrete or other cemented layers of road clothing is proposed in the article. The cracks in the cement containing materials may result from various factors: a discrepancy of thermal coefficient of linear expansion; cement heat output; inner stresses in structure of cement rock or in contact point “cement rock – filling aggregate”; improper care for arranged layer, constant heat and mass transfer (steam, water fluid phase) resulting in a temperature and moisture contrasts through thickness; shrinkage caused by physical and chemical processes when hardening of cement rock; traffic loads strain. In order to calculate the cement concrete layers of road clothing for crack resistance or how it’s indicated in CC В.2.3-37641918- 557:2016 “Rigid road clothing” – “6.1.3 Calculation of solid cement and concrete surface” it’s required to know a stress value from effect of above factors. It’s possible to define the stress in cement and concrete layers from traffic loads and temperature difference using CC В.2.3- 37641918-557:2016 “Rigid road clothing”, herewith the stress calculation from shrinkage at the moment of setting and hardening is ignored at all that maybe evidenced about lack of such calculation. However as practice shows a shrinkage stress in cement and concrete as well as other cement containing layers of the road clothing with crystallization structure reaches a value of traffic stress and tem – perature difference. That’s why it may become necessity in stress definition in cement containing materials with crystallization structure at the stage of setting and hardening until “traditional” 28 days. The object of study – contraction stresses of cement-concrete pavement layer of road clothing with a crystallization structure for setting and hardening. The aim of the work is to derive a mathematical dependence that simulates and makes it possible to estimate the distribution of contraction stresses that occur in a cement-concrete layer of road clothing. On the basis of the theoretical solution, a mathematical dependence is derived that simulates and makes it possible to estimate the distribution of contraction stresses that arise in a cement concrete or other cemented layers with a crystallization structure for setting and hardening. The theoretical solution is based on the theory of resilience. The obtained solution will make it possible to clarify the calculations of the durability of the cement concrete or other cemented layers with a crystallization structure.
The mathematical solution for determining the contraction stresses in the cementconcrete or other cemented layers of road clothing is proposed in the article. The cracks in the cement containing materials may result from various factors: a discrepancy of thermal coefficient of linear expansion; cement heat output; inner stresses in structure of cement rock or in contact point “cement rock – filling aggregate”; improper care for arranged layer, constant heat and mass transfer (steam, water fluid phase) resulting in a temperature and moisture contrasts through thickness; shrinkage caused by physical and chemical processes when hardening of cement rock; traffic loads strain. In order to calculate the cement concrete layers of road clothing for crack resistance or how it’s indicated in CC В.2.3-37641918- 557:2016 “Rigid road clothing” – “6.1.3 Calculation of solid cement and concrete surface” it’s required to know a stress value from effect of above factors. It’s possible to define the stress in cement and concrete layers from traffic loads and temperature difference using CC В.2.3- 37641918-557:2016 “Rigid road clothing”, herewith the stress calculation from shrinkage at the moment of setting and hardening is ignored at all that maybe evidenced about lack of such calculation. However as practice shows a shrinkage stress in cement and concrete as well as other cement containing layers of the road clothing with crystallization structure reaches a value of traffic stress and tem – perature difference. That’s why it may become necessity in stress definition in cement containing materials with crystallization structure at the stage of setting and hardening until “traditional” 28 days. The object of study – contraction stresses of cement-concrete pavement layer of road clothing with a crystallization structure for setting and hardening. The aim of the work is to derive a mathematical dependence that simulates and makes it possible to estimate the distribution of contraction stresses that occur in a cement-concrete layer of road clothing. On the basis of the theoretical solution, a mathematical dependence is derived that simulates and makes it possible to estimate the distribution of contraction stresses that arise in a cement concrete or other cemented layers with a crystallization structure for setting and hardening. The theoretical solution is based on the theory of resilience. The obtained solution will make it possible to clarify the calculations of the durability of the cement concrete or other cemented layers with a crystallization structure.
Description
Keywords
дорожнє покриття, цементобетон, вологопровідність, цементобетонне покриття, коефіцієнт усадки, масообмін, міра жолоблення, напруження усадки, теоретичне рішення, цементовмісний шар, road pavement, cement concrete, moisture conductivity, contraction coefficient, mass transfer, measure of warping, contraction stress, theoretical solution, cemented layer
Citation
Онищенко А. М. Оцінювання напружень від усадки в цементобетонному покритті автомобільних доріг / А. М. Онищенко, А. С. Лапченко, Н. П. Чиженко // Вісник Національного університету “Львівська політехніка”. Серія: Теорія і практика будівництва. — Львів : Видавництво Львівської політехніки, 2019. — № 912. — С. 132–138.