scholarly journals Acoustic Performance Evaluation of Dense-Graded Asphalt Pavements in Qatar

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Okan Sirin ◽  
Md Ohiduzzaman ◽  
Emad Kassem ◽  
Wahid Hassan
Keyword(s):  
Noise Level ◽  
Arabian Gulf ◽  
Asphalt Mixture ◽  
Sound Intensity ◽  
Low Noise ◽  
Asphalt Pavements ◽  
Test Results ◽  
Acoustic Performance ◽  
The Us ◽  
Repeatability And Reproducibility

There is pressing and growing demand from the public to design and construct roads with a low noise level. This paper investigated the acoustic performance of asphalt pavements in the State of Qatar to assist transport authorities in designing and constructing quieter pavements. In this study, a field-testing setup was assembled to measure the tire-pavement noise of dense-graded asphalt (DGA) pavements at the source using the on-board sound intensity (OBSI) method. The repeatability and reproducibility of test results demonstrated that the assembled OBSI test setup could measure the sound intensity with excellent repeatability and reproducibility. The measured noise level of existing pavements varied from 101.8 dBA to 106.2 dBA depending on the age of pavement sections. Measured noise levels of pavements in Qatar were higher than typical DGA pavements in Europe and the US. Test results also demonstrated that the acoustic performance of pavements in Qatar deteriorates faster compared to those in the US and Europe. The findings of this study demonstrate that there is a need to consider alternative asphalt mixture designs in Qatar and the Arabian Gulf. The results also showed a good correlation between the mean texture depth of studied pavement sections and noise level, especially at the low-frequency range.

scholarly journals Prediction Model of Asphalt Content of Asphalt Mixture Based on Dielectric Properties

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Yanhui Zhong ◽  
Yilong Wang ◽  
Bei Zhang ◽  
Xiaolong Li ◽  
Songtao Li ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Prediction Model ◽  
Room Temperature ◽  
Asphalt Mixture ◽  
Aggregate Size ◽  
Asphalt Pavements ◽  
Test Results ◽  
Wide Range ◽  
Asphalt Content ◽  
Ground Penetrating

The rapid detection of asphalt content in asphalt mixture is of great significance to the quality evaluation of asphalt pavement. Based on the dielectric properties of an asphalt mixture, the prediction model of asphalt content is deduced theoretically using three types of dielectric models: Lichtenecker-Rother (L-R) model, Rayleigh model, and Bottcher equation. Under the condition of laboratory mixing at room temperature (about 20–25°C), a dielectric test of asphalt mixture is conducted to verify the applicability of the model. The test results indicate that the dielectric constant of the asphalt mixture is inversely proportional to the asphalt content and directly proportional to the aggregate size of the mixture. Among the models, the Rayleigh model has a wide range of applications and exhibits a high accuracy, with an average relative error of only 1.86%. The results provide a theoretical basis for the nondestructive testing of asphalt pavements using ground-penetrating radar.

Pavement Performance of Hot In-Place Recycling for Waste Asphalt Mixtures

2013 ◽  
Vol 668 ◽  
pp. 292-296
Author(s):  
Ya Li Ye ◽  
Chuan Yi Zhuang ◽  
Jia Bo Hu
Keyword(s):  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Pavement Performance ◽  
Test Results ◽  
Technical Parameters ◽  
Stable Performance ◽  
Wheel Tracking Test ◽  
Asphalt Content ◽  
Wheel Tracking

With the early asphalt pavements have been into the stage of medium maintenance or overhaul, recycling is a very important way for waste asphalt mixtures. A sample was taken in the expressway from Huhhot to Baotou, and the waste mixtures were extracted from field and sieved; so that the new aggregates can be determined and mix design was carried. With the aid of the penetration, the softening point and the viscosity in 135°C test, the quantity of the regenerant and the asphalt content were ascertained. Through the high temperature stable performance, the anti-low temperature performance, the water stability and the Hamburg wheel-tracking test, the appropriate gradation and the optimum asphalt content were determined. The test results showed that the pavement performance of the waste asphalt mixture was enhanced obviously with hot in-place recycling, and it has achieved technical parameters for old asphalt mixture.

scholarly journals Analysis of Skid Resistance and Noise Characteristics for Varieties of Concrete Pavement

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Jinmiao Fang ◽  
Jinsong Tu ◽  
Kunming Wu
Keyword(s):  
Noise Level ◽  
Evaluation Criteria ◽  
Sound Intensity ◽  
Low Noise ◽  
Concrete Pavement ◽  
Skid Resistance ◽  
Concrete Pavements ◽  
Noise Levels ◽  
Cement Concrete ◽  
Noise Characteristics

To establish evaluation criteria for the pavement skid resistance and noise level in tunnels pavements, the zoning and control standards for skid resistance and concrete pavement noise were examined. Transverse friction coefficient (TFC) test equipment and the on-board sound intensity (OBSI) method were used to evaluate the antisliding characteristics and noise levels of several tunnel pavements. The results indicated poor antisliding characteristics and noise levels in ordinary grooved cement concrete pavement, whereas new types of cement concrete pavements, such as exposed concrete pavements and polymer-modified cement concrete pavements, had good antisliding characteristics and achieved low noise levels. Combined with the cluster analysis method, a zoning method for the antisliding and noise level in concrete pavement is proposed. The antisliding characteristics and noise levels of the pavement are divided into three zones. To ensure safety and comfort during driving, the antisliding value (SFC) of the tunnel pavement should be more than 50, and the noise level should not exceed 105 dB. Finally, the correlation between the antisliding and noise levels for pavement was analyzed. The results indicated that the antiskiding value of pavement has a strong correlation to the noise level.

Studies on Scroll Compressor Noise Improvement

2014 ◽  
Vol 694 ◽  
pp. 504-508
Author(s):  
Qing Miao ◽  
Yan Ru Men ◽  
Jin Xiang Wu ◽  
Xiang Gou
Keyword(s):  
Intensity Distribution ◽  
Noise Level ◽  
Sound Intensity ◽  
Specific Method ◽  
Test Results ◽  
Scroll Compressor ◽  
Root Cause ◽  
Additional Weight ◽  
Noise Characteristics ◽  
Noise Test

As the environment and customer are sensitive to compressor noise from refrigeration air condition system, it’s necessary to reduce noise level for scroll compressor to compete with piston one in this field. In this paper, we studied one way to detect noise resource and reduce noise level for scroll compressor; analyzed its vibration and noise characteristics; got the sound intensity distribution on the surface of compressor; performed the model test of the main part by using hammer strike and gained their intrinsic frequents. At last, by comparing the scroll compressor noise test results, sound intensity distribution, and intrinsic frequents, it was confirmed that upper shell resonation is the root cause to increase the noise. Also we gave a specific method, adding additional weight to upper shell, to avoid resonation. It’s proved to be efficient after test check.

scholarly journals The Influence of Aeolian Sand on the Anti-Skid Characteristics of Asphalt Pavement

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5523
Author(s):  
Jingsheng Pan ◽  
Hua Zhao ◽  
Yong Wang ◽  
Gang Liu
Keyword(s):  
Asphalt Pavement ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Test Results ◽  
Aeolian Sand ◽  
The Road ◽  
Gray Correlation ◽  
Positive Linear Correlation ◽  
Sand Accumulation

The influence of sand accumulation on the skid resistance of asphalt pavement was studied. Many scholars have researched the anti-skid performance of conventional asphalt pavements. However, there is a lack of research on the anti-skid performance of desert roads under the condition of sand accumulation. In this study, AC-13 and AC-16 asphalt mixtures were used. The British Pendulum Number (BPN) under different sand accumulations was measured with a pendulum friction coefficient meter, and the Ames engineering texture scanner was used to obtain different sand accumulations. The texture index of asphalt mixture was used to study the macro and micro texture of asphalt pavement under different amounts of sand accumulation, and the degree of influence of different particle sizes on BPN was obtained through gray correlation analysis. The test results show that the presence of aeolian sand has a significant impact on the macro and micro texture of the asphalt pavement and will cause the anti-skid performance to decrease. Moreover, there is an apparent positive linear correlation between the road surface texture index and BPN. The research results may provide reference and reference for the design and maintenance of desert highways.

Fan Blade Selection for Low Noise Part 1: Design Philosophy

1989 ◽  
Vol 203 (3) ◽  
pp. 149-154
Author(s):  
N Hay ◽  
J S B Mather ◽  
R Metcalfe
Keyword(s):  
Design Method ◽  
Separated Flow ◽  
Low Noise ◽  
Broadband Noise ◽  
Test Results ◽  
Flow Distortion ◽  
Acoustic Performance ◽  
Design Philosophy ◽  
Fan Blade ◽  
Lifting Surfaces

It has been known for many years that the broadband noise of rotating machinery is dependent on the condition of the boundary layers on the lifting surfaces. Designs with high efficiencies and clean flow have mainly produced low noise levels. These units have generally used high technology blading, with low inlet velocities and minimal separated flow. In the application of machines in industry, however, many are subject to inlet flow distortion and turbulence. These produce changes to the flow pattern around the blades which may have a relatively insignificant effect on the aerodynamics of the machine but almost completely destroy its acoustic performance. The design method described by Hay, Metcalfe and Reizes (15) allows the designer to pitch the operating point well away from stall. Thus low-response blading can be used for those installations whose flow conditions cannot be improved. This method is further developed in this paper using some correlations from McKenzie's work (17). The application of the method to the design of a low noise fan in the presence of a ±10 per cent perturbation on inlet velocity is given in way of illustration of the approach. In Part 2 of this paper (to be published later) it is hoped to demonstrate the validity of the design philosophy presented here with test results from fans designed according to this philosophy.

scholarly journals Selection of Constituent Materials for Asphalt Mixtures of Noise-Reducing Asphalt Pavements

2019 ◽  
Vol 14 (2) ◽  
pp. 178-207 ◽  
Author(s):  
Audrius Vaitkus ◽  
Ovidijus Šernas ◽  
Viktoras Vorobjovas ◽  
Judita Gražulytė
Keyword(s):  
Asphalt Pavement ◽  
Traffic Noise ◽  
Asphalt Mixture ◽  
Mixture Design ◽  
Asphalt Mixtures ◽  
Cold Climate ◽  
Asphalt Pavements ◽  
Test Results ◽  
Bituminous Binders ◽  
Selection Of

Road traffic noise is a widespread problem, especially in the densely populated cities of Europe. Exposure to high levels of (traffic) noise leads to health problems, such as stress, sleep disturbance and even heart diseases. Noise-reducing asphalt pavements are more frequently developed and selected as a first noise abatement solution. Performance of noise-reducing asphalt pavement depends on the composition and properties of asphalt mixture components, and pavement properties such as layer thickness, voids in pavement, texture. Design of asphalt mixture for the noise-reducing asphalt pavements is even more complicated for severe and cold climate regions where significant temperature fluctuations and many of frost-thaw cycles occur. Thus, the balance between mechanical and acoustical durability depends on the proper selection of asphalt mixture components. Components of these asphalt mixtures have primarily to be tested to determine their physical and mechanical properties. The main aim of this research is to evaluate properties of local aggregates, bituminous binders, and regarding test results, select the most suitable materials for the design of high-quality, durable asphalt mixture for noise-reducing asphalt pavements. The research showed that Granite A is the most suitable aggregate for the design of asphalt mixtures for noise-reducing asphalt pavement. Short-term and particularly long-term ageing of polymer modified bituminous binder PMB 45/80-65 and PMB 25/55-60 decreases the number of aromatics and increases the amount of resins. Based on Multiple Stress Creep and Recovery test results, it is assumed that all bituminous binders selected for research are suitable for the asphalt mixture design of noise-reducing asphalt pavement in terms of resistance to rutting. However, considering all tests results, bituminous binder PMB 45/80-65 (1) showed the best performance and was the most suitable for the asphalt mixture design of noise-reducing asphalt pavement.

scholarly journals Asphalt Pavement Acoustic Performance Model

2019 ◽  
Vol 11 (10) ◽  
pp. 2938 ◽  
Author(s):  
Rita Kleizienė ◽  
Ovidijus Šernas ◽  
Audrius Vaitkus ◽  
Rūta Simanavičienė
Keyword(s):  
Noise Reduction ◽  
Noise Level ◽  
Asphalt Mixture ◽  
Low Noise ◽  
Asphalt Mixtures ◽  
Mixture Composition ◽  
Void Content ◽  
Road Noise ◽  
Air Void ◽  
Air Void Content

Low-noise pavements are used as an effective method of traffic noise mitigation. Low-noise pavements reduce the noise that arises due to interactions between tires and road surfaces (tire/road) via the implementation of three main components: low pavement roughness, negative pavement texture, and a high pavement air-void content. The tire/road noise reduction capabilities of the wearing layer vary depending on the aggregate type, gradation, bitumen and air-void content, and density. Consequently, the demand for an accurate tire/road noise prediction model has arisen from the design of asphalt mixtures. This paper deals with how asphalt mixture components of the wearing layer influence tire/pavement noise reduction and presents a model for tire/road noise level prediction based on the asphalt mixture composition. The paper demonstrates that the noise reduction level of low-noise asphalt pavements is dependent on the composition of the asphalt mixture. Asphalt wearing layer mixture composition parameters were tested in the laboratory from cores taken from 18 road sections, where acoustic properties were measured using a close-proximity (CPX) method. The proposed linear model is based on the bitumen amount, the air-void content of the mixture and aggregate shape and involves materials that comply with the general requirements for high-quality asphalt mixtures. The model allows for the prediction of the tire/road noise level at the asphalt mixture design stage using asphalt mixture components and volumetric properties. The proposed model is the first stage in the building of a complex model with a much wider range of low-noise asphalts components, pavement profile depth and CPX-value relationships.

scholarly journals Evaluation of NOx Reduction Effect and Impact on Asphalt Pavement of Surface Treatment Technology including TiO2 and Asphalt Rejuvenator

2021 ◽  
Vol 11 (23) ◽  
pp. 11571
Author(s):  
Jong-Won Lee ◽  
Cheolmin Baek
Keyword(s):  
Surface Treatment ◽  
Removal Rate ◽  
Nox Reduction ◽  
Asphalt Mixture ◽  
Asphalt Pavements ◽  
Test Results ◽  
Treatment Technology ◽  
Treatment Agent ◽  
Reduction Effect ◽  
Effect Of Surface

Nitrogen oxide (NOx), emitted at the highest rate among automobile exhaust gases, is the main cause of air pollution, and various construction technologies are being developed to reduce NOx emissions. In this study, the NOx reduction effect of surface treatment technology for road pavements, and the effect of the photocatalytic reaction on asphalt pavements, were evaluated using a photocatalyst. Three types of titanium dioxide (TiO2) were used as photocatalysts, and an asphalt rejuvenator used to recover aged asphalt was applied as a surface treatment agent. To evaluate the NOx reduction effect, a test device capable of testing large-sized specimens was manufactured and compared with the ISO method, which only allowed the testing of small specimens. In addition, the effect of TiO2 and the asphalt rejuvenator on the asphalt mixture was analyzed through chemical analysis. The test results of the newly manufactured mixed-tank photo reactor showed the same trend as the ISO test results concerning the evaluation of its NOx removal performance. As a result of the performance evaluation of the surface treatment using TiO2, the NO removal rate was up to 7.83% when Anatase-type TiO2 with excellent light efficiency was applied. In addition, when the rejuvenator was used, the oxidation of asphalt, caused by the photoreaction of TiO2, was reduced.

Sign in / Sign up

Export Citation Format

Share Document