Keywords: road

EXAMINATION OF THE QUALITY OF NANOMATERIALS IN THE DEVELOPMENT AND APPLICATION OF CIRCULATING RESOURCES IN CONSTRUCTION

https://doi.org/10.34031/2618-7183-2021-4-6-48-68
Abstract
The advantage of the equality indicator is the relative simplicity of definition and the possibility of periodic monitoring. According to the equality indicator, it is possible to assign repairs and predict the service life, assess the condition of the road surface. Experimental studies have proved that there is a connection be-tween the evenness of the coating and the strength of the pavement, which opens up the possibility of determining the structural strength of non-rigid pavement, which provides a given evenness of the coating for the last year of operation before major repairs. The question of assessing the impact of the unevenness of the road surface on the processes of development and accumulation of deformations, changes in the evenness of the coating during operation remain largely open. This is due to the multifactorial nature of the problem of predicting the equality of coverage, so it is advisable to use approaches based on direct measurement methods. Most of the existing models of interaction of a pneumatic or rigid wheel with a coating are designed for problems of pavement mechanics or car theory, therefore they cannot be unambiguously applied to determine the value of the dynamism coefficient. A significant disadvantage of these solutions is insufficient consideration of the deformative properties (modulus of elasticity) of the pavement.
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OBTAINING A THERMAL INSULATION LAYER FROM MONOLITHIC NON-AUTOCLAVED STRUCTURAL AND THERMAL INSULATION FIBRE FOAM CONCRETE

https://doi.org/10.34031/2618-7183-2021-4-3-5-22
Abstract
The possibility of obtaining structural and thermal insulation foam concrete of non-autoclave hardening with improved construction and technical characteristics for the device of a thermal insulation layer in the con-struction of road pavement due to three-dimensional dispersed reinforcement with polypropylene fiber is theoretically justified and experimentally confirmed. Based on the results of studies of the influence of technological factors on the properties of foam concrete, the optimal content (up to 0.25% of the cement mass) and the length (12 mm) of reinforcing polypropylene fibers have been established, which allows obtaining high strength indicators of dispersed-reinforced cement stone for bending (an increase of 12-20%) and compression (an increase of 6-12%) compared with non-reinforced cement stone of non-autoclaved foam concrete. The analysis of the process of structure formation of dispersed reinforced foam concrete from the standpoint of a systematic approach based on multifactorial polynomial models of the influence of the ratio of filler and binder, as well as the number of dispersed reinforcing fibers, which is determined by the optimal conditions for the distribution of solid and gas phases, as well as the reinforcement of adjacent interstitial partitions of foam concrete, linking them into one asociate, which ensures the joint work of the material under various external influences. A method was developed to increase the durability of the road surface and eliminate the influence of the frost heaving effect on the quality of the road surface by introducing the necessary amount of effective thermal insulation layer into the road surface design. The analysis of the regularity of the heat transfer process in the soil mass of the roadbed and multilayer road pavement is carried out. Based on the analysis, the values of the necessary resistance to heat transfer of road pavement for the natural and climatic regions of the country are determined and a method for calculating the value of the thermal insulation (frost-proof) layer of road pavement is proposed. A method was developed for calculating the value of the thermal insulation layer using monolithic fibre foam concrete and a nomogram to determine the required value of the thermal insulation layer made of monolithic non-autoclaved structural and thermal insulation fibre foam concrete of classes D600-D1000.
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