scholarly journals Study the Using of Reed Mats in Asphalt Pavement Layers

2018 ◽  
Vol 4 (2) ◽  
pp. 346 ◽  
Author(s):  
Lamia Abdul Jaleel Ahmed ◽  
Ammar Fakhir Sabri

During the service life, the asphalt pavement layers subjected to various detrimental types of distresses such as permanent deformation, fatigue, stripping and shoving which lead to the complete failure of the pavement. In Iraq roads the permanent deformation (rutting) is the importance distresses which cause impact on the highway performance and reducing the service life of the pavement. The research aims to utilize locally available materials and environment friendly as reinforcement layer. The program of this research include preparing asphalt mixes represent surface layer by using locally available materials and using the reinforcement layer which made of reed. The permanent deformation test has been done with three temperatures (40˚C, 50˚C and 60˚C) and four locations of the reed mats. The test results of the wheel- Track for the rutting measurement showed that the rut depth decrease in reinforcement layers as compared with unreinforcement layers for all temperature testing. The reed netting embedded bottom and middle of wearing layer has the best amount of improvement (75%, 84% and 85%).

Recently, prices of asphalt pavement materials have been increasing tremendously, which led to attempts to find alternative cheap materials. In addition, more concerns are directed to reserving natural resources and reducing environmental impacts of using virgin asphalt binders, thus more attention is focused on the use of recycled materials in pavement designs. Transportation agencies worldwide are incorporating reclaimed asphalt pavement (RAP) materials in new pavement designs. RAP was used for the first time in 1973, however, with low percentages due to the lack of understanding of its effect on the performance of asphalt mixes. Currently, higher percentages (e.g. >50%) are being utilized to reduce costs and natural resources and make use of demolished old asphalt pavements. The main concern of combining RAP in new asphalt mixes is how it will affect the resistance of these mixes to permanent deformation (rutting), fatigue cracks, and thermal cracks, which are the main distresses that affect the performance of asphalt mixes. Many studies were conducted to evaluate the effects of RAP on asphalt mixes, and all results showed that RAP increased the stiffness of asphalt mixes, thus improving rutting resistance at high temperature. On the other hand, results were in conflict with regard to fatigue and thermal cracking. Recently, the Department of Public Works and Services at Ras Al Khaimah, UAE started adopting RAP mixes in ongoing projects (e.g. Kadra-Shawka Road) with no clear guidelines, in hope of reducing costs and that these roads would have better performance. To address the concerns of the effects of RAP and to determine the correct RAP percentage for projects in Ras Al Khaimah, this study was initiated and as a first stage a literature review was conducted and presented in this article.


2000 ◽  
Vol 1723 (1) ◽  
pp. 107-115 ◽  
Author(s):  
Bouzid Choubane ◽  
Gale C. Page ◽  
James A. Musselman

Findings are summarized from an investigation performed to evaluate the suitability of a wheel-tracking device known as the asphalt pavement analyzer (APA) for assessing the rutting potential of asphalt mixes. The evaluation process consisted of correlating the APA’s predicted rutting with known field measurements. The correlation between beam and gyratory samples and the testing variability were also investigated. In addition, the APA test results were compared with those obtained using the Georgia loaded-wheel tester. The findings of this investigation indicated that the APA may be an effective tool to rank asphalt mixtures in terms of their respective rut performance. However, for each mixture type, the APA testing variability was significant between tests and between the three testing locations within each test. Differences in rut measurements of up to 4.7 and 6.3 mm were recorded for beam and gyratory samples, respectively. Therefore, using the APA as a clear pass-or-fail criterion for performance prediction purposes of asphalt mixtures may not be appropriate at this time. It should be noted that these findings are based on data collected on three mixes. Therefore, it is suggested that the APA testing variability (testing and testing locations within the device) be further assessed with a wider range of mixtures. The intent of such an assessment should not only be to correlate the APA results with field data but also to develop potential pass-or-fail limits and procedures.


2018 ◽  
Vol 21 (1) ◽  
pp. 20 ◽  
Author(s):  
Amjad H. Albayati ◽  
Esraa T. Al-Azawee

Improving the ability of asphalt pavement to survive the heavily repeated axle loads and weathering challenges in Iraq has been the subject of research for many years. The critical need for such data in the design and construction of more durable flexible pavement in bridge deck material is paramount. One of new possible steps is the epoxy asphalt concrete, which is classified as a superior asphalt concrete in roads and greatly imparts the level of design and construction. This paper describes a study on 40-50 penetration graded asphalt cement mixed with epoxy to produce asphalt concrete mixtures. The tests carried out are the Marshall properties, permanent deformation, flexural fatigue cracking and moisture damage. Epoxy asphalt mixes performed better on resistance to fatigue and permanent deformation. They also performed significantly better on low-temperature properties and resistance to moisture damage. The addition of 30 percent of epoxy (by weight of asphalt cement) resulted in increase of Marshall stability by 39.8 percent, improve the tensile strength ratio by 22.9 percent, lowering both the rate of permanent deformation by 26.8 percent and the fatigue accumulation coefficient by 53.5 percent, in comparison with control HMA. Based on the above findings, it is recommended to use epoxy asphalt mixes as an optimal material for paving bridges deck in Iraq since it showed good prospects for this application due to the valuable performance and durability improvement.


Author(s):  
Morteza Ghaffari Jajin ◽  
Niloofar Esmaeili ◽  
Gholam Hossein Hamedi

Rutting is a common damage of flexible pavements, reducing the service life of asphalt pavement. Due to laboratory limitations, asphalt mixtures are subjected to different curing times (since construction until placement in the test chamber) and thermal equilibrium times (since placement in the test chamber until the beginning of the test) before rutting tests. Neglecting these factors can lead to errors in the laboratory results. Therefore, the present study attempted to investigate the effect of curing times of 1, 2, and 3 days at 25ºC and thermal equilibrium times of 2, 4, and 6 hours on the rutting potential of different hot-mix asphalt (HMA) mixtures. Results of rutting tests showed that the rutting potential of asphalt mixtures decreases by increasing the curing time, while the permanent deformation at the end of loading cycles and rutting potential increase by increasing the thermal equilibrium time. Additionally, the results of statistical analyses revealed that curing time and thermal equilibrium time change the rutting potential of asphalt mixtures.


2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Mohammad Ashiqur Rahman ◽  
Rouzbeh Ghabchi ◽  
Musharraf Zaman ◽  
Syed Ashik Ali

AbstractDespite significant economic and environmental benefits, performance of warm mix asphalt (WMA) containing reclaimed asphalt pavement (RAP) remains a matter of concern. Among the current WMA technologies, the plant foaming technique (called “foamed WMA” in this study) has gained the most attention, since it eliminates the need for chemical additives. In the present study, the laboratory performance, namely rutting and moisture-induced damage potential of foamed WMA containing RAP were evaluated and compared with those of similar hot mix asphalt (HMA) containing identical amount of RAP. Dynamic modulus, Hamburg wheel tracking (HWT) and flow number tests were performed to assess the rutting resistance of the mixes. Also, stripping inflection point from HWT tests and tensile strength ratio after AASHTO T 283 and moisture induced sensitivity test (MIST) conditioning were used to evaluate the moisture-induced damage of asphalt mixes. It was found that MIST conditioning effectively simulates the moisture-induced damage and can capture the propensity of asphalt mixes to moisture damage more distinctly compared to AASHTO T 283 method due to application of cyclic loadings. The foamed WMA was found to exhibit higher rutting and moisture-induced damage potential due to lower mixing and compaction temperatures compared to HMA. However, the increase in RAP content was found to reduce rutting and moisture-induced damage potential for WMA. Therefore, the lower stiffness of foamed WMA may be compensated with the addition of stiffer binder from RAP.


Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4238
Author(s):  
Piotr Pokorski ◽  
Piotr Radziszewski ◽  
Michał Sarnowski

The paper presents the issue of resistance to permanent deformations of bridge pavements placed upon concrete bridge decks. In Europe, bridge asphalt pavement usually consists of a wearing course and a protective layer, which are placed over the insulation (waterproofing). Protective layers of bridge pavement are commonly constructed using low air void content asphalt mixes as this provides the suitable tightness of such layers. Due to increased binder content, asphalt mixes for bridge pavement may have reduced resistance to permanent deformations. The article presents test results of resistance to permanent deformations of asphalt mixes for the protective layers. In order to determine the composition of mixtures with low air void content and resistance to permanent deformation, an experimental design was applied using a new concept of asphalt mix composition. Twenty-seven different asphalt mixture compositions were analyzed. The mixtures varied in terms of binder content, sand content and grit ratio. Resistance to permanent deformation was tested using the laboratory uniaxial cyclic compression method (dynamic load creep). On the basis of experimental results and statistical analysis, the functions of asphalt mixture permanent deformation resistance were established. This enabled a determination of suitable mixture compositions for protective layers for concrete bridge decks.


2014 ◽  
Vol 1023 ◽  
pp. 28-31
Author(s):  
Li Min Li

With the constant increasing of traffic flow and axle load, the early failure of semi-rigid base asphalt pavement is increasingly serious in China. The bad durability and short service life of pavement have become main obstacles in road construction development. Based on the experience of successful application, the early failure of semi-rigid base asphalt pavement is solved, and the service life of pavement is increased by using of the composite asphalt pavement. To solve the design problem of the composite asphalt pavement , its mechanical properties influence results of are obtained by the factors, such as shear strain, shear stress, compression strain on top of subgrade, etc, by a lot of calculation using Shell pavement design software. These provide theoretical basis for durable asphalt pavement design based on rut-resistance property.


2015 ◽  
Vol 749 ◽  
pp. 278-281
Author(s):  
Jia Horng Lin ◽  
Jing Chzi Hsieh ◽  
Jin Mao Chen ◽  
Wen Hao Hsing ◽  
Hsueh Jen Tan ◽  
...  

Geotextiles are made of polymers, and their conjunction with different processes and materials can provide geotextiles with desirable characteristics and functions, such as filtration, separation, and drainage, and thereby meets the environmental requirements. Chemical resistant and mechanical strong polymers, including polyester (PET) and polypropylene (PP), are thus used to prolong the service life of the products made by such materials. This study proposes highly air permeable geotextiles that are made with different thicknesses and various needle punching speeds, and the influences of these two variables over the pore structure and mechanical properties are then examined. PET fibers, PP fibers, and recycled Kevlar fibers are blended, followed by being needle punched with differing spaces and speeds to form geotextiles with various thicknesses and porosities. The textiles are then evaluated for their mechanical strength and porosity. The test results show that a thickness of 4.5 cm and 1.5 cm demonstrate an influence on the tensile strength of the geotextiles, which is ascribed to the webs that are incompletely needle punched. However, the excessive needle punching speed corresponding to a thickness of 0.2 cm results in a decrease in tensile strength, but there is also an increase in the porosity of the geotextiles.


2018 ◽  
Vol 34 ◽  
pp. 01026
Author(s):  
Ahmad Kamil Arshad ◽  
Haryati Awang ◽  
Ekarizan Shaffie ◽  
Wardati Hashim ◽  
Zanariah Abd Rahman

Reclaimed Asphalt Pavement (RAP) is old asphalt pavement that has been removed from a road by milling or full depth removal. The use of RAP in hot mix asphalt (HMA) eliminates the need to dispose old asphalt pavements and conserves asphalt binders and aggregates, resulting in significant cost savings and benefits to society. This paper presents a study on HMA with different RAP proportions carried out to evaluate the volumetric properties and performance of asphalt mixes containing different proportions of RAP. Marshall Mix Design Method was used to produce control mix (0% RAP) and asphalt mixes containing 15% RAP, 25% RAP and 35% RAP in accordance with Specifications for Road Works of Public Works Department, Malaysia for AC14 dense graded asphalt gradation. Volumetric analysis was performed to ensure that the result is compliance with specification requirements. The resilient modulus test was performed to measure the stiffness of the mixes while the Modified Lottman test was conducted to evaluate the moisture susceptibility of these mixes. The Hamburg wheel tracking test was used to evaluate the rutting performance of these mixes. The results obtained showed that there were no substantial difference in Marshall Properties, moisture susceptibility, resilient modulus and rutting resistance between asphalt mixes with RAP and the control mix. The test results indicated that recycled mixes performed as good as the performance of conventional HMA in terms of moisture susceptibility and resilient modulus. It is recommended that further research be carried out for asphalt mixes containing more than 35% RAP material.


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