Mechanics Analysis of the Structure of Fly-Ash-Flushed-by-Seawater Base Asphalt Pavement under Heavy Load

2012 ◽  
Vol 256-259 ◽  
pp. 1866-1870
Author(s):  
Ling Yu ◽  
Jing Yang ◽  
Long Sheng Bao ◽  
Guang Shan Zhu
Keyword(s):  
Fly Ash ◽  
Tensile Stress ◽  
Asphalt Pavement ◽  
Structural Parameters ◽  
Structural Parameter ◽  
Structural Stress ◽  
Road Asphalt ◽  
Heavy Load ◽  
The Road ◽  
Road Pavement

In order to find out the loading mechanism of Fly-Ash-Flushed-by-Seawater base asphalt pavement under heavy load and verify reasonable road pavement structure, this paper analysed the road model under different axel load with ABAQUS. The influence of structural stress and the road asphalt pavement deflection in different road structural parameters were shown in the paper. The result indicates that the structural stress and the deflection under heavy load are greater than they are under the standard load. When the vehicle is over load by 100％, the tensile stress of subbase is close to the allowable tensile stress. The structure of Fly-Ash-Flushed-by-Seawater base asphalt pavement can be designed to adapt to the over load traffic of Yingkou by adjusted the structural parameter in a certain range.

The Tension Fracture Simulation on the Asphalt Pavement with the Insufficient Compaction Roadbed

2011 ◽  
Vol 243-249 ◽  
pp. 3868-3872
Author(s):  
Lai Gui Wang ◽  
Mei Sheng Feng ◽  
Hong Zhu Zhang
Keyword(s):  
Tensile Stress ◽  
Asphalt Pavement ◽  
Crack Model ◽  
Tension Stress ◽  
Wheel Load ◽  
Tension Crack ◽  
Discontinuous Surface ◽  
The Road ◽  
Fracture Simulation ◽  
Pavement Structure

For the study of soft subgrade pavement cracking process, it establishes the pavement structure tension crack model by elastic layered theory. Based on the finite element method, it studies the tension crack evolution process. It establishes the tension crack stress criterion to the roadbed. Analysis shows that the distresses of asphalt pavement of the real highway results from the damage by asymmetric sedimentation which is under excessively axle loading on pavement structure, rather than the fatigue damage by axle loading repetitions in the condition of asymmetric intensity in the same layer. The results show that the soft degree of the subgrade is proportional to the tensile stress, the more localized soft, the easier to crack the road. The soft roadbed does not have a homogeneous structure of the road surface, the tension stress rupture occurred in the discontinuous surface. The road structure has a set of tensile stress under the circulation wheel load, it formats a new fracture surface, and the structure form corresponding evolves, and causes stress state change. At last most of the road sub-base crack, and surface cracking occurres, so the pavement failure.

Dynamic Response of Asphalt Pavement on Semi-Rigid Base due to Heavy Load

2013 ◽  
Vol 405-408 ◽  
pp. 1745-1752
Author(s):  
Li Juan Zhang
Keyword(s):  
Shear Stress ◽  
Surface Layer ◽  
Tensile Stress ◽  
Compressive Stress ◽  
Asphalt Pavement ◽  
Road Surface ◽  
Rigid Base ◽  
Heavy Load ◽  
Vertical Strain ◽  
Surface Deflection

The purpose of this paper is to study dynamic-characteristics of asphalt-pavement on semi-rigid base loaded with moving, heavy-load. Based on transient-dynamics theory, three-dimensional finite-element (FE) model was developed for structural dynamic-responses analysis using ANSYS software. The heavy-duty axle-load model was established according to Belgium-Design Code, and the dynamic-load was simplified as sinusoidal-wave load. For the pavement mechanics indexes (road-surface deflection, the vertical and lateral stress, the shear stress and the strain), the time-history curves and distribution conditions in the structure were presented. Expect tensile-strain at surface-layer, the relationship between axle-load weight and mechanic-indexes are almost linearly proportional. The calculation shows that under moving heavy-load, the surface-layer suffers from rather high vertical compressive-stress and shear-stress, the base and subbase are loaded with high tensile-stress and the subgrade top undergoes large vertical-strain . For asphalt-pavement on semi-rigid loaded with moving, heavy-load, besides the conventional indexes (including road-surface deflection and tensile-stress at the bottom of base or subbase), the design indexes should also include the shear-stress on road surface, the vertical-strain on the top of subgrade and the vertical compressive-stress on road surface.

scholarly journals Porous asphalt pavement for traffic noise reduction and pavement dewatering – the pollution problem

2018 ◽  
Vol 45 ◽  
pp. 00114
Author(s):  
Lesław Bichajło ◽  
Krzysztof Kołodziej
Keyword(s):  
Asphalt Pavement ◽  
Traffic Noise ◽  
Asphalt Mixture ◽  
Porous Asphalt ◽  
The Road ◽  
Road Pavement ◽  
Pollution Problem ◽  
Pavement Construction ◽  
Air Void ◽  
The City

The paper characterizes the porous asphalt mixture used in pavement construction. This kind of pavement can reduce traffic noise and reduce the slipperiness of the road pavement. The effectiveness of the porous asphalt depends on many design and technological aspects, but especially on the air-void clearance in the pavement layer. The paper includes the results of water permeability research based on laboratory tests of specimens from actual road pavement. The research shows the differences between the contamination of the road pavement sections located inside and outside the city. The paper includes recommendations for using porous asphalt based on experiences under Polish conditions.

Effect of Asphalt Layer Modulus on the Mechanical Properties and Service Life of Heavy Load Semi-Rigid Asphalt Pavement

2011 ◽  
Vol 368-373 ◽  
pp. 193-196
Author(s):  
Xiao Hua Wang ◽  
Ji Shu Sun ◽  
Tian Xiao ◽  
Hui Ran Pi
Keyword(s):  
Mechanical Properties ◽  
Service Life ◽  
Tensile Stress ◽  
Asphalt Pavement ◽  
Pavement Design ◽  
Heavy Load ◽  
Surface Deflection ◽  
Pavement Structure ◽  
Base Course ◽  
Design Result

Asphalt layer modulus is one of the important mechanical parameters in pavement design. It will directly influence the design result and the mechanical properties of asphalt pavement structure. Using pavement design and analysis software, the effects of asphalt layer modulus on surface deflection, tensile stress at the bottom of base and sub-base course, stress at the the bottom of asphalt layer and service life of heavy load semi-rigid asphalt pavement structure were analyzed systematically. And the influencing laws were analyzed, too. The results indicate that the mechanical properties, deforming characteristics and service life of heavy load asphalt pavement were influnced significantly by asphalt layer modulus. With the increasing of asphalt layer modulus, the surface deflection, tensile stress at the bottom of base and sub-base course would significantly decrease, and service life of heavy load semi-rigid asphalt pavement structure would be improved.

scholarly journals Evaluating the Fatigue Resistance of the Innovative Modified-Reinforced Composite Asphalt Mixture

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Gholamali Shafabakhsh ◽  
Mahdi Akbari ◽  
Hossein Bahrami
Keyword(s):  
Fatigue Life ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Fatigue Behaviour ◽  
Road Asphalt ◽  
The Road ◽  
Road Pavement ◽  
Four Point Bending ◽  
Reinforced Composite ◽  
Traffic Loads

Fatigue failure is regarded as one of the most common failures in the road pavement and necessitates spending huge cost annually to maintain the road. Asphalt binder modification and asphalt mixture reinforcement are among the commonly used methods to increase the pavement resistance to a failure caused by fatigue. By proposing a modified-reinforced composite hot mix asphalt (MRC-HMA), the present study aimed to examine the fatigue life of this mixture with one of the most traditional methods (i.e., four-point bending beam fatigue test) and compare it at constant strain conditions and the strain levels of 500, 700, and 900  μ ε and a temperature of 20 ± 0.8 ° C to that of the other three specimens, including control specimens, geogrid-reinforced (GR-HMA) specimens, and nanosilica-modified (NSM-HMA) specimens with 5% nanosilica. In all experiments, the condition to reach the failure stage was assumed equivalent to a 50% reduction in the stiffness coefficient in each load repetition, and the load was applied semisinusoidal at a frequency of 10 Hz without rest. The results showed that the MRC-HMA mixture improved the fatigue life at the strain level of 500  μ s by about 701, 172.5, and 156.4% compared to the control, NSM-HMA, and GR-HMA specimens, respectively. Based on the results, the use of GR-HMA specimens has almost the same results as NSM-HMA ones, but the use of the MRC-HMA mixture can significantly increase the fatigue life of MRC-HMA in all three levels of strain compared to all specimens studied in the present study. Thus, the introduced mixture can be a proper choice for pavements with heavy or light (with a large amount) traffic loads, which usually have a vast adverse effect on the fatigue behaviour of asphalt mixtures.

scholarly journals Asphalt Layer Density and Air Voids Content: GPR and Laboratory Testing Data Reliance

2020 ◽  
Vol 15 (3) ◽  
pp. 93-110
Author(s):  
Andrius Baltrušaitis ◽  
Audrius Vaitkus ◽  
Juris Smirnovs
Keyword(s):  
Asphalt Pavement ◽  
Relative Dielectric Permittivity ◽  
Void Content ◽  
Air Voids ◽  
The Road ◽  
Layer Density ◽  
Road Pavement ◽  
Ground Penetrating ◽  
Air Void ◽  
Air Void Content

The assurance of asphalt pavement layer compaction, expressed by ratio between field and laboratory bulk density and air voids content, is one of the main criteria of the durability of asphalt road pavement. Destructive measures should be applied and cores should be taken from the asphalt pavement seeking to determine the representative compaction level of the constructed asphalt layers. New methods are constantly being sought for fast, non-destructive and accurate asphalt layer density and air void determination on road. Ground Penetrating Radar (GPR) can allow determining the qualitative characteristics of asphalt pavement across the entire length of the road without causing damage to the road structure. Relative dielectric permittivity, usually called dielectric value or constant, is the leading property used in GPR applications on road pavement surveys. This article presents GPR measurement results from asphalt base and binder layers of four test sections. GPR measurements were conducted immediately after the end of asphalt layer compaction process. Test points on each layer were selected and density, air void content were determined by drilling cores and testing them in the laboratory. To estimate asphalt layer density and air void content, GPR data were analysed using different existing mathematical models. To justify the reliability of the data measured by GPR, results were checked by comparing them with the results measured directly on cores taken from the asphalt pavement layers.

scholarly journals Long Term Behaviour of An Asphalt Pavement Structure Constructed on a Geogrid-Reinforced Subgrade Over Soft Soils

2019 ◽  
Vol 14 (3) ◽  
pp. 384-404
Author(s):  
Aurimas Šiukščius ◽  
Viktoras Vorobjovas ◽  
Audrius Vaitkus ◽  
Šarūnas Mikaliūnas ◽  
Atis Zariņš
Keyword(s):  
Load Transfer ◽  
Asphalt Pavement ◽  
Soft Soil ◽  
Soft Soils ◽  
Geogrid Reinforcement ◽  
The Road ◽  
Road Pavement ◽  
On The Road ◽  
Term Performance

Many roads with asphalt pavement are being reconstructed every year, as their quality becomes insufficient by the requirements. As it is well- known, old roads were built not in the very best quality, so doing reconstruction projects in the most cases there were required to deal with soft soils that are under the existing road structure. Geogrid reinforcement was widely used to solve issues of soft soil in Lithuania. There are projects where geogrid reinforcement is used to control road pavement roughness when there are layers of peat or silt under road structure instead of using concrete piles or geosynthetic-encased soil columns. This type of geogrid reinforcement application is unexplained in any normative-technical document but widely used in Lithuania. This application was usually made constructively without any calculations, choosing the reinforced solution by reducing the geogrid tensile strength or layer quantity compared to reinforced load transfer platform over piles. This paper evaluates the long-term influence of geogrid- reinforced subgrade on the roughness of asphalt surfacing and bearing capacity of the road structure when the soft peaty soils stratify in the deeper layers of the subgrade. There were compared the reinforced sections to adjacent sections to see the effect and fortunately a large number of adjacent sections were also strengthened, mostly by lime stabilisation. Therefore, this comparison allows making more insights on the long-term performance of the strengthened subgrade and influence on the road quality. This research gives recommendations on how the geogrids has to be selected to be used in this kind of application.

scholarly journals Geotechnical Evaluation of Road Pavement Failure along the Awotan-Akufo Road, Oyo State Southwestern Nigeria

2019 ◽  
pp. 1-11
Author(s):  
Apanpa, A. Kazeem ◽  
Olayiwola, Hameed ◽  
Anjonrin, Ademola
Keyword(s):  
Moisture Content ◽  
Asphalt Pavement ◽  
Optimum Moisture Content ◽  
Traffic Load ◽  
California Bearing Ratio ◽  
Engineering Properties ◽  
Southwestern Nigeria ◽  
The Road ◽  
Road Pavement ◽  
Natural Moisture Content

In order to access the cause(s) of road failure and proffer preventive measures for the future reconstruction of the Awotan-Akufo road, southwestern Nigeria, the geotechnical engineering properties of the subgrade soil, asphalt pavement thicknesses, drainage and traffic load were evaluated. Soil samples were collected from test pits 1 m deep and at an interval of 50 m and subjected to geotechnical analyses in accordance to AASTHO specification. The grain size distribution revealed that 70% of the entire samples from Awotan-Lifeforte and Adaba failed sections along Akufo road contain amount of fines more than 35% passing through sieve No. 200. The Natural Moisture Content range from 5.73 - 20.21% (Awotan-Lifeforte section) and the entire samples from Adaba failed sections have high natural moisture content ranging from 16.20 - 23.20%. From Atterberg limit test, the Liquid limit of 12 - 56% (Awotan-Lifeforte section) and 26.00 - 40.00% (Adaba Section) were obtained. The Plastic Limit and Plasticity Index of the soils ranges from 8.43 to 49.10% and 1.01 to 7.0% (Awotan-Lifeforte section), and 23.10 - 35.50% and 1.50 - 7.10% (Adaba Section) respectively. Linear shrinkage varies from 0.80 to 9.60% and from 3.10 to 8.80% for Awotan-Lifeforte and Adaba sections, respectively. The Maximum Dry Density of the soils ranged from 1.625 - 1.835 mg/m3 at Optimum Moisture Content of 13.4 - 17.3% (Lifeforte-Awotan section), and MDD of 1.752 - 1.975mg/m3 at Optimum Moisture Content of 13.4-17.3% (Adaba section). The unsoaked California Bearing Ratio are 30.08, 70.14, 39.08%, and the soaked California Bearing Ratio values are 26.17, 11.41, 33.41% (Lifeforte-Awotan section) respectively. At Adaba section of the road, the unsoaked California Bearing Ratio is 3.46, 87.70, 70.14%, and soaked California Bearing Ratio values are 3.42, 32.56, 39.83%. The average asphalt pavement thicknesses around Awotan-Lifeforte section range from 0.60 - 1.10 inches, and that of Adaba section range from 0.57 to 1.46 inches. The study concluded that the road pavement subgrade is silty clay and the geotechnical properties rated below the specifications of the Federal Ministry of Works and Housing at some failed portions. Asphalt pavement thicknesses are grossly inadequate and far below NAPA 2007 recommendation. As such the road cannot withstand the heavily loaded trucks that ply it on regular basis. All aforementioned contributed to the untimely failure of the road.

scholarly journals Characteristics of Mixed Porus Asphalt with Combination of LDPE, CPO and PEN 60/70

2021 ◽  
Vol 1 (4) ◽  
pp. 19-24
Author(s):  
Meidia Refiyanni ◽  
Chaira Chaira
Keyword(s):  
Asphalt Pavement ◽  
Asphalt Mixture ◽  
Test Results ◽  
Porous Asphalt ◽  
The Road ◽  
Road Pavement ◽  
Asphalt Content ◽  
Poly Ethylene ◽  
The Second Variation

The quality of the road depends on the pavement, drainage conditions, and materials. For this reason, it is necessary to make innovations in improving the quality of road pavement, one of which is increasing the material. There are many types of pavements, one of which is porous asphalt pavement. Porous asphalt has many cavities that is easy for water to pass but has a low stability value with high           permeability. This research will utilize Low Density Poly Ethylene (LDPE), as an additive, CPO, and Pen 60/70 in a porous asphalt mixture. The purpose of this study was to determine the characteristics of the porous asphalt mixture by substituting LDPE and CPO for Pen 60/70. The method used in analyzing the characteristics of the porous asphalt mixture refers to the specifications of the Australis Asphalt Pavement Association (AAPA) (2014), with parameters Camtabro Loss (CL), Asphalt Flow Down (AFD), VIM, stability and flow. The gradation used in this study is an open gradation. This research was started from determining the value of Optimum Asphalt Content (KAO), with two variations, namely Variation 1 (1% LDPE, 10% CPO, 89% pen 60/70), variation 2 (5% LDPE, 10% CPO, 85% Pens 60/70). The KAO value of variation 1 is 5.03% and the second variation is 4.75%. After obtaining the KAO value, LDPE and CPO are substituted. The test results for the porous asphalt mixture for CL values were 34.12% and 27.07%, respectively; AFD value of 0.13% and 0.12%; for the VIM value of 14.90% and 19.03%; stability value 603.24 kg and 603.19 kg; and flow values are 5.03 mm and 4.80 mm. In general, the value obtained from the test meets the required requirements. However, the durability value of the mixture did not meet the requirements, namely 60.15% and 48.22%, with the condition >90%.

Experimental Analysis for Piezoelectric Transducers Applications into Roads Pavements

2013 ◽  
Vol 684 ◽  
pp. 253-257 ◽  
Author(s):  
Salvatore Cafiso ◽  
M. Cuomo ◽  
A. Di Graziano ◽  
C. Vecchio
Keyword(s):  
Energy Production ◽  
Asphalt Pavement ◽  
Piezoelectric Transducers ◽  
Traffic Load ◽  
Road Asphalt ◽  
Pavement Materials ◽  
The Road ◽  
Network Connection ◽  
Load Effects ◽  
The One

The purpose of this study is to validate the use of piezoelectric transducers into the road asphalt pavement in terms of effectiveness and production of energy. FEM and laboratory test were conducted for transducers within an asphalt pavement, in order to study traffic load effects, the better suitable position, the pavement materials and environmental factors influence. The energy produced by the piezoelectric transducer within the pavement is very low if referred to a single sample as the one in the experiment and when compared to the amount which can be produced by the transducer not embedded in the pavement layers. It is necessary to highlight that higher energy production can be obtained using PZT of different size and with a network connection.

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