Academic Journal
The investigation of the frost resistance of the aggregate-sand mixes
| Τίτλος: | The investigation of the frost resistance of the aggregate-sand mixes |
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| Πηγή: | Bulletin of Kharkov National Automobile and Highway University; Vol. 1 No. 103 (2023); 198 Вестник Харьковского национального автомобильно-дорожного университета; Том 1 № 103 (2023); 198 Вісник Харківського національного автомобільно-дорожнього університету; Том 1 № 103 (2023); 198 |
| Στοιχεία εκδότη: | Kharkіv National Automobile and Highway University, 2023. |
| Έτος έκδοσης: | 2023 |
| Θεματικοί όροι: | щебенево-піщана суміш, frost resistance, tensile strength, гранулометричний склад, granulometric composition, морозостійкість, границя міцності при стиску, compressive strength, границя міцності на розтяг при розколі, aggregate mix |
| Περιγραφή: | Problem. Recently there is a steady trend to the increase of the intensity of traffic and of the loads from the wheels of the rolling stock on the whole structure of the road pavement, therefore during the building of the road pavement layers the most important thing is a rational choice of the materials for the base layers and for the top layers which will provide the performance of the entire structure during the designed service life under the working conditions which are getting worse all the time. Nowadays the most widespread material for the road base layers is aggregate mix strengthened by cement. One of the ways of the base layers materials improving is the increase of their frost resistance. One of the ways to solve this problem can be the different additive and fibers usage as a reinforcing component of the aggregate mix. But until today the influence of the internal factors such as size of mineral grains, granulometric composition and binder content on the indexes of frost resistance is still not investigated. Goal. The aim of the research is the investigation of the maximum grain size and content and also mineral binder concentration influence on the indexes of frost resistance of the aggregate mixes strengthened by cement. Methodology. To achieve this goal in the laboratory of the Department of Highway Building and Maintenance named after O. Birulia the samples of sand, fine-grained, medium-grained and coarse-grained aggregate mixes with cement content from 2 to 10 % were prepared. Results. For the frost resistance indexes determination of the aggregate mixes of different compositions strengthened by cement according to the maximum grain size the cement concentration influence on the grade strength indexes was found. The research results have shown that:with the increase of cement content the compressive strength indexes in the fine, medium and coarse-grained mixes are increasing; the increase of the maximum grain size of the same cement concentration shows that compressive strength and tensile strength indexes are increasing. The repeated freezing and thawing is one of the main aggressive factors of the external environment influence which reduces strength and durability of the materials, therefore the influence of this factor on the compressive strength and tensile strength was evaluated. In Ukraine according to the current standard the frost resistance of the aggregate mixes is evaluated only in terms of compressive strength index of samples which were subjected to certain number of freeze-thaw cycles. It is determined that the aggregate mixes with the same cement content with larger mineral grains in its composition have higher indexes of the frost resistance coefficient. Also it was found that the influence of the freeze-thaw cycles is more informatively shown at the samples testing according to the split tensile test. Conclusions: 1. The increase of the binder content in the composition of strengthened aggregate mixes leads to the decrease of the freeze-thaw cycles influence on the compressive strength and splitting strength for all studied compositions of aggregate mixes. 2.The aggregate mixes strengthened by the same cement amount with the larger size of mineral grains in its composition have higher values of frost resistance coefficients in comparison with strengthened aggregate mixes with smaller maximum size of mineral grains in its composition. 3.The influence of the freeze-thaw cycles is showed more informatively by the split tensile scheme. В якості шарів основи дорожніх одягів все частіше використовуються щебенево-піщані суміші укріплені цементом. Головним недоліком цих шарів є їх низька морозостійкість. В роботі виконано дослідження впливу вмісту цементу та гранулометричного складу мінеральної частини укріплених щебенево-піщаних сумішей на їх марочну міцність. Визначені коефіцієнти морозостійкості укріплених сумішей за різних схем випробувань. |
| Τύπος εγγράφου: | Article |
| Περιγραφή αρχείου: | application/pdf |
| Γλώσσα: | Ukrainian |
| ISSN: | 2219-5548 2521-1773 |
| Σύνδεσμος πρόσβασης: | http://bulletin.khadi.kharkov.ua/article/view/294031 |
| Αριθμός Καταχώρησης: | edsair.scientific.p..69b7df4e3dd853451cde28c3b8f7839b |
| Βάση Δεδομένων: | OpenAIRE |
| ISSN: | 22195548 25211773 |
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