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

2022 ◽  
Vol 4 (6) ◽  
pp. 48-68
Author(s):  
S. Plehanova ◽  
N. Vinogradova

the advantage of the equality indicator is the relative simplicity of definition and the possibility of periodic moni-toring. 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 between 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 be-fore 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 disad-vantage of these solutions is insufficient consideration of the deformative properties (modulus of elasticity) of the pavement.

2021 ◽  
Vol 334 ◽  
pp. 01027
Author(s):  
Valentina Yadykina ◽  
Rashid Sharapov ◽  
Christina Pashkova ◽  
Anatoly Gridchin ◽  
Anna Trautvain

Based on literature data, the paper analyzed the impact of transport operational indicators related to the quality of road surface coverage on road safety. It presented the results of experimental studies on the effect of the road adhesion cationic thermostable additive on the properties of bitumen and asphalt concrete. The authors identified that the introduction of this additive leads to an increase in the viscosity and softening temperature of bitumen, its adhesion to mineral materials, which has a positive effect on strength, water resistance, shear stability, crack resistance, fatigue durability of asphalt concrete. The conclusion was made about the regularity of improving road safety, related to the improvement of the quality of the pavement, arranged from asphalt concrete with the application of the tested additive.


Author(s):  
Mikhail E. Piletsky ◽  
Anatoly F. Zubkov ◽  
Konstantin A. Andrianov ◽  
Marianna A. Porozhenko

Increased traffic intensity and increased axial Load from vehicles on road surfaces contribute to the formation of defects in the form of potholes and cracks. To improve the service Life and traffic safety timely care of the coating is required. Untimely work Leads to a decrease in the service Life of the pavement. The use of a jet-injection method of repair of road surfaces aLLows to perform work quickLy with minimaL cost in reLation to other methods of repair. The articLe considers the process of eLimination of defects on non-rigid road surfaces with the use of bitumen-mineraL mixtures by a jet-injection method. The resuLts of experimentaL studies carried out in the course of repair work on the second technicaL category road with high traffic intensity and increased axiaLLoad from vehicLes are presented. It was found out that the formation of the structure of the bitumen-mineraL mixture in the pothoLe of the road surface occurs over a reLativeLy Long period of time. Under the influence of contact stresses under the tire of the car, there are deformations of the material, the excess of whichLeads to its decompression. It is experimentaLLy proved that in order to increase the serviceLife of the repaired road surface, additionaL compaction of the bitumen-mineraL mixture is necessary. It was found that the excessLoad on the Layer of bitumen-mineraL mixture in the pothoLe coating at the stage of formation of its structure above the tensiLe strength contributes to the formation of pLastic deformations and reduce the required compaction coefficient. To improve the quaLity of repair work, it is necessary to Limit the axiaLLoad of vehicLes on the surface of the pothoLe for 20-30 days during the formation of the structure of the Laid materiaL in the pothoLe of the road surface.


2020 ◽  
Vol 9 (1) ◽  
pp. 922-933
Author(s):  
Qing’e Wang ◽  
Kai Zheng ◽  
Huanan Yu ◽  
Luwei Zhao ◽  
Xuan Zhu ◽  
...  

AbstractOil leak from vehicles is one of the most common pollution types of the road. The spilled oil could be retained on the surface and spread in the air voids of the road, which results in a decrease in the friction coefficient of the road, affects driving safety, and causes damage to pavement materials over time. Photocatalytic degradation through nano-TiO2 is a safe, long-lasting, and sustainable technology among the many methods for treating oil contamination on road surfaces. In this study, the nano-TiO2 photocatalytic degradation effect of road surface oil pollution was evaluated through the lab experiment. First, a glass dish was used as a substrate to determine the basic working condition of the test; then, a test method considering the impact of different oil erosion degrees was proposed to eliminate the effect of oil erosion on asphalt pavement and leakage on cement pavement, which led to the development of a lab test method for the nano-TiO2 photocatalytic degradation effect of oil pollution on different road surfaces.


2022 ◽  
Vol 10 (1) ◽  
Author(s):  
Fatima Safi ◽  
Anna M. Aniserowicz ◽  
Heather Colquhoun ◽  
Jill Stier ◽  
Behdin Nowrouzi-Kia

Abstract Background Eating disorders (ED) can reduce quality of life by limiting participation and performance in social and occupational roles, including paid or unpaid work. The association between ED pathologies and work participation and performance must be well understood to strengthen vocational rehabilitation programmes and prevent occupational disruptions in the ED population. The aims of this study are: (1) to examine the degree of association between ED pathologies and work participation and performance in 15-year-olds and older; (2) to highlight the specific ED symptoms that are most correlated with changes in work performance and participation; (3) to compile the most common metrics and assessments used to measure work participation and performance with ED. Methods Medline, Embase, CINAHL, Web of Science, PsycINFO, and Cochrane Library will be searched for observational and experimental studies that meet the following criteria: (1) a clinical sample of typical or atypical ED; (2) paid or unpaid employment or training; (3) an association between ED pathologies and work participation or performance. Unpublished data will also be examined. Title and abstract, and full-text screening will be conducted in duplicate. Risk of bias and quality of evidence assessments will be completed. A random-effect meta-analysis will be performed. Discussion This synthesis can clarify knowledge and gaps around the impact of ED on work functioning, thereby allowing better evaluation, improvements and development of current workplace assessments, interventions, and policies. Trial registration The registration number for this systematic review on PROSPERO is CRD42021255055.


2015 ◽  
Vol 54 (1) ◽  
pp. 101-109 ◽  
Author(s):  
Jurgita Židanavičiūtė ◽  
Audrius Vaitkus

The data were collected by researchers at the Road Research Institute, in a study investigating the impact of differentfactors on road surface strength. In this statistical analysis, we apply linear mixed models (LMMs) to clustered longitudinal data, inwhich the units of analysis (points in the road) are nested within clusters (sample of four different road segments), and repeatedmeasures of road strength in these different points are collected over time with unequally spaced time intervals. The data arebalanced – each cluster has the same number of units, which are measured at the same number of time points. Because of correlateddata and different clusters in which data could be correlated, linear regression models are not appropriate here, and therefore linearmixed models are applied.


Author(s):  
Aleksandr N. Kononov ◽  
Anastasia S. Komissarova

Topicality of the study of the attitude to the distance learning format is due to the need to study the impact of such interaction in the “pedagogue-studentˮ system on the quality, motivation and overall satisfaction of students with the learning process. The study involved 120 people from 6 six higher education institutions in Moscow. The use of content analysis allowed us to identify 8 significant contexts (areas) around which the statements of the study participants are grouped: “Roadˮ, “Teachersˮ, “Returnˮ, “Distance learningˮ, “Full-time, full-time attendingˮ, “Training, training formatˮ, “Provided, changedˮ, “Qualityˮ. The results obtained indicate that the main disadvantages of the distance learning format, according to the respondents, are the lack of live communication with teachers, a decrease in the level of motivation and self-organisation, which ultimately has a negative impact on the psychoemotional state of students and the quality of material assimilation. At the same time, among the obvious advantages, there is a reduction in transport and time costs for the road to the place of study, as well as the opportunity to study the material at a convenient time. The results obtained can be used in the development of distance learning programmes for students of higher educational institutions of the Russian Federation.


2011 ◽  
Vol 346 ◽  
pp. 711-718 ◽  
Author(s):  
Li Xia Meng ◽  
Fu Chun Sun ◽  
Hua Ping Liu ◽  
Tao Chu

A navigation method is presented for intelligent vehicle based on fusion of double laser radar. Given laser radar model and road curb model, road curbs are detected by one laser radar tilt-mounted on the intelligent vehicle, and they restrict the vehicle to travel inside the road surface. First, obstacle information from two laser radar are unified to same reference frame and fused, then they are implemented using angle potential field method, the best navigation angle is computed under the road curb restriction. Experiments show the algorithm works well in spite of road-boundary has regular shape or not, and is free from the impact of height difference of the road curb and road surface.


2012 ◽  
Vol 204-208 ◽  
pp. 1843-1847
Author(s):  
Da Wei Wang ◽  
Hua Liang Chen

Obtained through the large number of field core samples from a variety of strength tests, the impact of the construction technology of concrete pavement structural strength spatial variability of the distribution law of the strength of concrete in the pavement structure, to find out the variability characteristics of the structural strength, to determine the structural design of reliability coefficient to provide a basis. On the basis of theoretical studies and experimental studies, practical techniques for pavement concrete structure and properties of the variability of design control and construction control, to control the variability of pavement concrete structural strength.


Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3429 ◽  
Author(s):  
Agnieszka Skoczylas ◽  
Kazimierz Zaleski

In this article, we report the results of experimental studies on the impact of ball burnishing parameters on the roughness, microstructure and microhardness of the surface layer of laser-cut C45 steel parts. We also analysed the distribution of residual stresses generated in the surface layer of these parts. Laser-cut parts often require finishing to improve the quality of their surface. The tests performed in this study were aimed at assessing whether ball burnishing could be used as a finishing operation for parts of this type. Ball burnishing tests were performed on an FV-580a vertical machining centre using a mechanically controlled burnishing tool. The following parameters were varied during the ball burnishing tests: burnishing force Fn, path interval fw and the diameter of the burnishing ball dn. Ball burnishing of laser-cut C45 steel parts reduced the surface roughness parameters Sa and Sz by up to 60% in relation to the values obtained after laser cutting. Finish machining also led to the reorganization of the geometric structure of the surface, resulting in an increase in the absolute value of skewness Ssk. This was accompanied by an increment in microhardness (maximum microhardness increment was ΔHV = 95 HV0.05, and the thickness of the hardened layer was gh = 40 µm) and formation of compressive residual stresses in the surface layer.


Sign in / Sign up

Export Citation Format

Share Document