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The advancement in the tensile strength and ductility of plain concrete can minimize the quantity of materials required per unit strength to build eco-friendly structures. This paper compares the compressive and flexural behavior of different strength classes (C20, C30, and C45) of concrete with the varying volume fractions of hooked steel fiber (HSF) considering the application of concrete road. The performance of each strength class was evaluated and compared based on the compressive and tensile testing results. Using the mechanical properties of concrete mixtures; the design thickness, cost, and global warming potential of concrete pavement were calculated and compared between different mixes under the same traffic loadings. The results showed that the maximum utilization of HSF was observed in the high-strength C45, whereas HSF showed comparatively low efficiency in low-strength C20. At 0.25% volume of HSF, low strength C20 concrete showed higher residual strength and flexural toughness than that of the plain high strength C45 concrete. The analysis of design thickness of pavements revealed that low-strength C20 at 0.25–0.5% HSF can provide cost-effective and eco-friendly pavements compared to a plain high strength C45 for the same design loadings. The results of this study provide useful insights on the selection of strength class and concentration of steel fiber for pavement application.

Despite the fact that our country's road network is inferior to that of industrialized countries, the volume of motor traffic is increasing. Thus, optimal solutions are imperative during both project and construction phases of highway investments. Concrete superstructures offer an alternative to flexible superstructures in various regions globally, including airport runways, warehouses, urban roads, streets, highways and industrial buildings. The objective of this study was to enhance the compressive and flexural strength of concrete and provide resistance against abrasion. To achieve this, a roller compressible concrete (RCC) mixture design was developed by incorporating basalt fiber, nano TiO2, and nano Fe2O3 additives. The experimental results were subjected to statistical analysis via the technique of analysis of variance (ANOVA). The findings of the study indicated that the strength performance of the optimal RCC mixture design reinforced with nano powder and fibers was superior to that of conventional concrete. Upon examination on a material basis, it was determined that the compressive strength exhibited an increase when the water/binder ratio was utilised within the range of 0.38–0.4. As the utilisation of nano-Fe2O3 and basalt fiber materials increased, their compressive strength exhibited a corresponding enhancement. The incorporation of basalt fiber into the composite material resulted in an increase in flexural strength at all ratios where it was utilised. It can be concluded that basalt fiber has the greatest potential for enhancing flexural strength. The optimal water-to-binder ratio for flexural properties is between 0.34 and 0.38. While nano powders can have a positive impact, they cannot achieve the maximum level of strength. For improving abrasion resistance, it was established that reducing the water/cement ratio, using fly ash, basalt fiber, and nano Fe2O3 in the mixture decreased abrasion. However, the usage of nano TiO2 did not have a significant positive effect. The material with the least effect on compressive, flexural and abrasion resistance was identified as nano TiO2. When materials other than nano TiO2 are utilised in accordance with the established optimal mixture calculation, the durability of the resulting RCC road will reach the requisite standard.

The advancement in the tensile strength and ductility of plain concrete can minimize the quantity of materials required per unit strength to build eco-friendly structures. This paper compares the compressive and flexural behavior of different strength classes (C20, C30, and C45) of concrete with the varying volume fractions of hooked steel fiber (HSF) considering the application of concrete road. The performance of each strength class was evaluated and compared based on the compressive and tensile testing results. Using the mechanical properties of concrete mixtures; the design thickness, cost, and global warming potential of concrete pavement were calculated and compared between different mixes under the same traffic loadings. The results showed that the maximum utilization of HSF was observed in the high-strength C45, whereas HSF showed comparatively low efficiency in low-strength C20. At 0.25% volume of HSF, low strength C20 concrete showed higher residual strength and flexural toughness than that of the plain high strength C45 concrete. The analysis of design thickness of pavements revealed that low-strength C20 at 0.25–0.5% HSF can provide cost-effective and eco-friendly pavements compared to a plain high strength C45 for the same design loadings. The results of this study provide useful insights on the selection of strength class and concentration of steel fiber for pavement application. [ABSTRACT FROM AUTHOR]

The use of recycled aggregates instead of natural aggregates used in concrete reduces environmental pollution and concrete costs. Recycled Asphalt Pavement (RAP) aggregate used as recycled aggregate has a lower water absorption than natural aggregate due to its bituminous structure, which reduces the water requirement of fresh concrete. In this study, it was aimed to determine the optimum use of RAP particles as aggregate in concrete for read pavements and to determine their durability properties. For this purpose, RAP was used instead of crushed stone aggregate used in concrete road construction. RAP was used by replaced aggregate 0%, 25%, 50% and 100% of the crushed stone aggregate used on the concrete road. The dose of the produced concrete was 350 kg/m3 and the water/cement ratio was kept constant as 0.45. The fresh workability and air content of concretes containing RAP were determined. Compressive strength, splitting tensile strength, electrical resistivity value, accelerated corrosion test of hardened concretes were subjected to corrosion resistance, water absorption and porosity percentage, acid resistance, ultrasonic pulse rate and Scanning Electron Microscope (SEM) and X-ray Diffractometer (XRD) analyzes were determined. In the experimental results, it has been observed that the use of RAP ratio of 25% and 50% remains within the limit values for concrete pavement. It is recommended to be used on reinforced concrete roads that will be exposed to adverse environmental conditions with its high corrosion resistance, thanks to its anti-corrosion feature.

In 2020 Indonesia began to recover from the covid-19 pandemic. The refocusing policy carried out by the government of the Republic of Indonesia for handling COVID-19, where most of the focus is on spending on health equipment and materials. As a result, many construction works were canceled or budget reductions occurred. Increased competition among providers for jobs has resulted in providers submitting bids of less than 80% of the estimated own price (HPS) when participating in tenders. The research was conducted on concrete road improvement activities in Grobogan Regency during the Covid-19 period, namely in 2020 and 2021. The data used for the analysis is secondary data consisting of the name of the work package, the HPS value, the number of bidders, and the results of the compressive strength test of concrete. The thickness of the laid concrete. From this study, the number of bidders is the factor that most influences the bid proportion. Jobs with an offer of <80% HPS value have more samples that do not match the plan's quality than jobs with an offer of>80% HPS value. At an offer <80%, the HPS value has some samples that are less than the planned volume, which is more when compared to work with an offer > 80% HPS value. [ABSTRACT FROM AUTHOR]

Bu çalışmada, farklı tür agregalardan üretilen silindirle sıkıştırılmış beton (SSB) örneklerinin özellikleri araştırılmıştır. Bağlayıcı olarak CEM I 42,5 R Portland çimentosu, dolomit, bazalt, mermer ve iki farklı tür kalker olmak üzere beş farklı agrega, doğal kum ve şebeke suyu kullanılmıştır. Agrega örnekleri üzerinde sıkışık ve gevşek birim hacim ağırlık, özgül ağırlık, su emme, Los Angeles parçalanma direnci tayini ve elek analizi deneyleri yapılmıştır. Farklı tür agregalarla yapılan karışımlarda su/çimento oranı 0,35 olarak sabit tutulmuştur. Dolomit, bazalt, mermer, iki farklı tür kalker olmak üzere beş farklı agreganın her biri 12-19 mm kırmataş II, 4-12 mm kırmataş I ve 0-4 mm kırmataş tozu olarak kullanılmıştır. Ayrıca farklı agrega ile üretilen betonların her birinde 0-4 mm boyutunda doğal kum kullanılmıştır. 7 ve 28 günlük basınç dayanımlarının belirlenmesi için 15 cm çapında ve 30 cm yüksekliğinde silindir, 28 günlük eğilme dayanımı için ise 15 cm×15 cm×75 cm boyutlarında prizmatik kiriş örnekler üretilmiştir. Eğilme dayanımı testinden önce 28 günlük prizmatik kiriş numunelerden yararlanılarak ultrases geçiş hızı ve dinamik elastisite modülü değerleri belirlenmiştir.

Roller compacted concrete (RCC) is a material with no slumps and is made from the same raw materials as conventional concrete. The roller compacted dam method, the high paste technique, the corps of engineers method, and the maximum density method are all ways of designing RCC. The evolution of RCC has resulted in a substantial change in construction projects, most notably in dams, because of the sluggish pace of conventional placement, consolidation, and compacting. The construction process was accelerated by incorporating RCC into dams, resulting in a shorter construction period. Research shows that the dams that used RCC had completed one to two years sooner than the dams that used regular concrete (Bagheri and Ghaemian's, 2004). The application of RCC has risen significantly during the past several decades, particularly for pavement applications. It has a lower construction cost than asphalt and may be completed fast. It is extensively used in areas/roads that transport big goods at moderate speeds. RCC is increasingly being used in metropolitan areas, particularly on roadways and streets. RCC has shown great interest in asphalt roads in terms of durability, compressive strength, prolonged service life, and lower maintenance costs. Fibre addition is frequently favored in RCC, just as in traditional concrete. Fiber inclusion contributes to the mechanical qualities of RCC as well as its long-term sustainability. Within the focus of this research, RCC is reviewed based on four factors: environmental effect, cost, fiber addition, and country-specific RCC use. This study is unusual in this sense and provides researchers with valuable information

[Introduction] The purpose of this paper is finding out the differences in the calculation of concrete road structure between Chinese codes and American codes, looking for the possibility of Chinese code to replace American code in the calculation of concrete road structure, making Chinese codes more widely used in the world. [Method] We compared the theoretical principles and design process of concrete road design between Chinese codes and American codes, then the same project example is calculated by the methods of Chinese codes and American codes respectively, and we compared the result and got a conclusion. [Result] After comparison, we find that the results calculated by Chinese codes and American codes are very close, Chinese codes are more conservative that can increase the life of concrete roads. [Conclusion] In the concrete road design of foreign projects, Chinese codes can replace American coads. We can use Chinese codes boldly, and help them to go to the world.

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Infrastructure development is a global priority. Most countries are investing enormous financial resources on high-quality, safe and sustainable roads. Taking into account the pace of technology development, it is currently not only building roads but complex projects. In the Republic of Moldova, as is well known, the situation with the roads is very difficult, in some regions they are practically only on paper. The article contains a description of the modern practices and technologies implemented in some countries regarding the construction and materials used for road clothing, as well as smart solutions on motorways.

An analysis of vibration signals has been proposed for a personal gasoline-engine car while driving on three types of roads including paved road, concrete road, and gravel road. The wired sensors are placed upon three positions inside the passenger room: right-front seat surface, left-front seat surface, and rear seat surface. The objectives of this analysis are to differentiate the corresponding vibration reflecting from driving upon three types of roads and to differentiate the vibration at three different positions of sensors inside the passenger room. The signal analysis technique of Fast Fourier Transform is utilized in this analysis, the obtained spectrum is investigated to extract the dominant peaks. Thereafter, the averages of the peak values are calculated for six different engine speeds ranging from 0-30 km/h. These averaging calculations are based on 50 five-second-length samples of vibration signals. To achieve the first objective, the experimental results insist that the highest peak values are mostly of the gravel road, meanwhile, the lowest peak values are of the paved road. To accomplish the second objective, the experimental results strongly confirm the following comparisons. In the case of paved road, the highest peak values are at the rear seat surface, meanwhile, in the case of concrete road, the highest peak values are at the left-front seat surface. Finally, in the case of gravel road, the highest peak values are at the rear seat surface. In conclusion, this study confirmed that the proposed approach can be used to differentiate the signal features of all scenarios. [ABSTRACT FROM AUTHOR]

Studded tyres wear surfaces of winter roads, generating inhalable airborne particles. In this study, four concrete road materials and two stud geometries were investigated in terms of wear, road material hardness and airborne particle concentration. The sliding contact between studded tyres and road materials was studied using a pin-on-disc machine in a clean chamber. The results show that the normal load and the stud size have a large influence on the wear and particle emission. It was found that the wear and particle concentration are inversely proportional to the hardness of the aggregate in the road material and proportional to the sliding distance. The particle size distribution has peaks at 0.2 µm, 1 µm and 2 µm. [ABSTRACT FROM AUTHOR]

Human hair fibers are abundantly available as waste and wave polypropylene fibers are commercially available. These fibers are studied with limited scope from only material point of view. In this study, the mechanical properties of hair fiber reinforced concrete (HFRC) and wave polypropylene fiber reinforced concrete (WPFRC) are explored for its possible applications in concrete roads. The properties are experimentally evaluated as per ASTM standards and the effectiveness of fibers in concrete are checked by comparing with that of control mix. In addition, by using the relevant properties, concrete road design is also compared. It is found that the compressive, flexural and splitting-tensile strengths of HFRC are improved by 12.4%, 16.2% and 19.1%, respectively, and that of WPFRC are increased by 11.7%, 21.5% and 17.5%, respectively. With these improvements, the thickness of concrete road for a particular studied loading condition can be reduced by 12.5 mm. This can result in cost saving (per lane per km) of 3% and 1.7% by use of HFRC and WPFRC, respectively. The performance of concrete road is also expected to be better because of improved toughness of HFRC and WPFRC. [ABSTRACT FROM AUTHOR]

Carbon dioxide emissions mitigation from road construction activities is one of potential pathways to deal with climate change. Aiming to estimate the magnitude of carbon dioxide emissions and identify the uncertainty from construction phase of real entire road projects including road structures and earthworks apart from pavement, this paper applied Life Cycle Assessment on 20 asphalt projects and 18 concrete road projects which were classified into high-grade road and low-grade road. The impact of uncertain data source and system boundary on results was checked, followed by discussion with previous studies. The findings show that average total emissions per kilometer per lane are variety but nearly 500 t for concrete and 1250 t for asphalt road. Carbon dioxide emissions comparison of asphalt road in this study with previous studies indicates that emissions of entire road project are 1.92 times higher than that of studies only considering pavement, 27% higher than that of studies without considering bridge and tunnel. Materials contribute to largest emissions in both asphalt road and concrete road, but off-road machinery even accounts for 45% of total emissions in concrete road. Emission of off-road machinery in asphalt road in this study is 13.6% higher than that of studies only considering pavement. Efforts should focus on earthworks and structures, and on improvement in off-road machinery performance not only on materials. Lack of consideration on phase of chemical reactions for cement in asphalt road and pre-consumption for fuel in concrete road could underestimate 15% of total emissions respectively. Recycling steel and electricity structure improvement play a weak role in road construction emissions reduction. For both concrete road and asphalt road, emissions of low-grade road are about 13% lower than that of high-grade road. [ABSTRACT FROM AUTHOR]

In this study, 3 types of concrete as C30/37 concrete, fibrous Reactive Powder Concrete (fibrous RPC) and non-fibrous Reactive Powder Concrete (non-fibrous RPC) were chosen for rigid pavement thickness and cost calculations. Concrete pavement thicknesses were calculated according to compressive and flexural strength results. Also calculated concrete pavement thickness values and rigid pavement cost calculations were done. In the study, non-fibrous RPC pavement thickness was calculated as 17.15 cm, fibrous RPC pavement thickness was calculated as 17.17 cm and C30/37 concrete pavement thickness was calculated as 23.04 cm in rigid pavement that is 8.2 Tones Equivalent Single-Axe Load Absolute Frequency (W8.2)10x106. At the end of study, as cost for 1 km length of concrete pavement according to W8.2=10x106 value, it was found out that cost of non-fibrous RPC pavement is 19.51% more economic than the cost of C30/37 concrete pavement. [ABSTRACT FROM AUTHOR]

Abstract: The use of titanium dioxide (TiO2) as a photocatalyst in concrete pavements has received considerable attention in recent years due to its ability to decontaminate via photocatalytic processes. The objective of this study is to assess the effectiveness of activated concrete road in the degradation of nitrogen oxides (NOx). We have used a TiO2 and activated carbon (AC) permeable spray solution to coat concrete to assess its NOx purifying ability. A number of experiments were undertaken to ascertain the conditions that affect NOx purification. Indoor simulation experiments with active concrete road at optimum conditions show that it has good purification ability, self-regeneration and repetition ability, with a minimum decontamination rate for NO and NO2 of 37.4% and 25.84%, respectively. Outdoor experiments show that the photodegradation of NOx is related to light intensity and temperature. As the light intensity increases the reaction rate increases, and conversely as temperature increases the reaction rate decreases. [Copyright &y& Elsevier]

This study aims at researching of concrete road and its building. It's an unarguable fact that transportation easiness is a big factor in terms of development of a state. Compared with developed countries, transportation net is insufficient and traffic intensity at our roads is increasing and road coverings falls to a big duty due to traffic intensity which is increasing. In this study, some information is given about the features of concrete roads, their advantages and their construction and it's concluded that by comparison with other toad types concrute road can give beter results in most aspects. Thanks to literateur studies, it is known that being used at our state's roads concrete roads technology which are used for 100 years in America, for 75 years in Europe will make a major contribution to the state economy. It is determined that concrete roads have many advantages such as, the vehicles stop at shorter distances, they can be made in every seasons at every condition, they can provide an increase at traffic speed, they stand up to factors such as weather conditions and fuel-oil spillovers. They are environmentally friendly, the home made materials are used, concrete roads suffer less from seasonal damages, they can be provide fuel saving, they are long-lasting, they make the night sight easy. It is thought that the importance, given in other developed states to concrete roads, should ve given to our country. [ABSTRACT FROM AUTHOR]