Optimum Bitumen Content Research Articles

Effects of recycled concrete aggregate on stiffness and rutting resistance of asphalt concrete

The objective of this research was to assess the possibility of using recycled concrete aggregate (RCA) in asphalt mixtures. The experimental research included 10 asphalt mixtures with partial natural aggregate substitution by RCA, which ranged from 15% to 45% of fine (⩽4mm), coarse (4/22.4mm) and both fine and coarse aggregate. The optimum bitumen content increased with increasing RCA content. The use of RCA had no significant influence on the permanent deformation, while the stiffness modulus of asphalt mixtures with RCA was lower compared with the control mixture, especially at high frequencies. The results indicate that RCA can be successfully used in asphalt mixtures.

The Assessment of Natural Rock Asphalt for Thin Surfacing Mixture Design

Thin surfacing hot mixed asphalt is one of the alternatives to anticipate the problem of thickness on overlay that are being developed as environment-friendly pavement, but the use of thin surfacing was still not maximum with some weakness. One way to improve the qualities of bitumen is by the use of the modification which has been available in the market. A new materials available in market is retona. Retona (Refined Buton Asphalt) is produced by the extraction of the natural asphalt from Buton island, Indonesia that were developed with a distillation process and extraction. The study has been carried out to define optimum bitumen content and characteristic in hot mix thin surfacing by using retona blend 55 and asphalt penetration 60 / 70 with the experimental method using the Marshall to define the stability, flow, density, percentage number of pores, Marshal Quotient (MQ). Result of Marshall test thin sufacing hot mix asplhat for optimum bitumen content retona belnd 55 asphalt is 5,87%, using the same gradations achieved optimum bitumen content of asphalt penetration 60/70 of 5.80%. In each of the asphalt on the conditions of optimum bitumen content obtained difference for characteristic and properties. Stability value retona blend 55 asphalt 525,61 kg, and asphalt penetration of 60/70 is 651,16 kg. The density value of retona blend 55 asphalt 2,06%, and asphalt penetration 60/70 is 2,11%. The percentage of the pores value of retona blend 55 asphalt is 18,45%, and asphalt penetration 60/70 is 15,8%. Flow value retona blend 55 asphalt is 2,11mm, and asphalt penetration 60/70 is 2,23mm. Thus asphalt penetration have resistance to traffic loads which is stronger, with a more solid density value, the value of smaller pores and higher flow values than the natural rock asphalt blend retona 55 asphalt.

Stability and Volumetric Properties of Asphalt Mixture Containing Waste Plastic

The objectives of this study are to determine the optimum bitumen content (OBC) for every percentage added of waste plastics in asphalt mixtures and to investigate the stability properties of the asphalt mixtures containing waste plastic. Marshall stability and flow values along with density, air voids in total mix, voids in mineral aggregate, and voids filled with bitumen were determined to obtain OBC at different percentages of waste plastic, i.e., 4%, 6%, 8%, and 10% by weight of bitumen as additive. Results showed that the OBC for the plastic-modified asphalt mixtures at 4%, 6%, 8%, and 10% are 4.98, 5.44, 5.48, and 5.14, respectively. On the other hand, the controlled specimen’s shows better volumetric properties compared to plastic mixes. However, 4% additional of waste plastic indicated better stability than controlled specimen.

Design and Properties of Renewable Bioasphalt for Flexible Pavement

In the construction world, most flexible pavement constructions use synthetic asphalt made from crude oil and well-known as conventional asphalt. Therefore, to find more environmentally friendly construction people around the world are very interested in finding a bioasphalt. The bioasphalt is used because of several reasons, such as asphalt mixtures derived from plants and trees could replace petroleum-based mixtures. One of bioasphalt which can be used as an alternative material of conventional asphalt is resin (damar). The existence of damar in Indonesia is very huge, especially in Lampung, South Sumatera, Indonesia. In this study, the researchers used experimental research based on laboratory works. The percentages of natural resin used in the conventional asphalt 60/70 pen are 0%, 2.5%, 5%, 7.5% and 10% modification. The selected test, including Marshall stability test to get the optimum bitumen content, unconfined compressive test, indirect tensile test and permeability test. The research result shows that asphalt with resin is different with conventional asphalt 60/70 pen in terms of asphalt quality, because the asphalt modified with resin has higher penetration value and specific gravity than conventional asphalt. The result of the Marshall stability test, unconfined compressive test, indirect tensile test and permeability test is high if the asphalt modified with higher natural resin. On the other hand, the optimum bitumen content value relatively similar with the modification of natural resin.

Plastic Bottles Waste Utilization as Modifier for Asphalt Mixture Production

Plastic Bottles was used as the polymeric waste to investigate performance of asphalt mixture Aggregates obtained from Margalla, Burhan and Karak quarries. 12 samples were prepared for conventional asphalt mixtures and 48 samples were prepared for PB modified asphalt mixture of each quarries at various proportions of PB waste. The PB used for modification according to wet process are 15%, 20%, 25% and 30% by weight of Optimum Bitumen Content (OBC). OBC of 4.2 % was concluded for conventional asphalt mixtures. The stability and flow values of the conventional and modified Asphalt Mixture were compared. The average Stability of the modified Margalla asphalt mixtures when 15% PB was used was much higher as compared to conventional asphalt mixtures. But when PB was used beyond 15%, the Marshall stability showed a decreasing trend for Margalla aggregates, increasing trend for Karak aggregates and decreasing trend for Burhan aggregates. This decline in stability is attributed to a decline in interlocking of aggregates due to lubricating effect. The corresponding flow for the Modified asphalt mixtures first showed a decreasing trend for Margalla aggregates at 15% PB modification but beyond 15%, an increasing trend in flow as compared to conventional asphalt mixtures The decrease in flow or increase in Marshall Stability is attributed to improvement in interlocking and decline in flow or stability is attributed to a decline in interlocking offered by binder and PB coated aggregate particles in modified asphalt.

Comparison of Flexible (Dense Graded) and Porous (Open Graded) Asphalt Surface Course with Stone Dust as a Filler in Marshal Mix Design

Bituminous concrete is the surface layer which will be laid to ply the vehicles above it & to transfer the vehicular wheel loads effectively without undergoing any major deformations. The grading of aggregates for bituminous concrete used for the analysis is as per MORTH & gap/open graded for porous asphalt as per NAPA specifications, the analysis done for dense graded asphalt is grade 2 where the nominal size of the aggregates is 13mm as per MORTH specifications. The present study has been taken to evaluate the Marshal property of both Bituminous concrete (Dense graded) & Porous (open/gap graded) asphalt, the tests revealed that there is a significant variation of Optimum binder content for dense graded mix when compared to porous (gap/graded) asphalt surface course. Preliminary tests have been carried out for bitumen & aggregates of specified sizes as per IS standards and results are tabulated. There is a considerable variation of OBC in both open & dense graded mixes where optimum bitumen content is more in dense graded mix when compared to open graded mixes whereas the flow values for open graded mix is more when compared to close graded mixes.

The Influence of Coconut Shell as Coarse Aggregates in Asphalt Mixture

Significant quantities of coconut shell (CS), a by-product of agriculture, can be used as an artificial source of coarse aggregates. In this study, four CSs were used as coarse aggregates replacement in asphalt concrete with 0%, 10%, 20%, 30%, and 40% weight volumes. The particle sizes of the CSs used as main coarse aggregates range from 5 mm to 20 mm. The Marshall Stability test shows that the optimum bitumen content for asphalt mixtures is 5.1%. The engineering properties investigated include the volumetric, dynamic creep, indirect tensile strength, and resilient modulus. Test results show that stability decreases with increasing CS content because of high water absorption. Considering that CSs absorb bitumen, a further detailed investigation is needed to assess the performance of modified bitumen on mixture. Furthermore, the use of CSs as coarse aggregates in asphalt concrete help increase the resilient modulus, stiffness, and indirect tensile strength up to 30%. Generally, a 10% replacement of coarse aggregates with CSs is the optimal limit.

Effect of bitumen grade on hot asphalt mixes properties prepared using recycled coarse concrete aggregate

The research aims at evaluating the effect of using recycled coarse concrete aggregates (RCA) on the basic properties of hot mix asphalt made with different grades of bitumen (60/70 and 80/100). First, recycled aggregate properties have been determined and compared to those of normal aggregates. Except for absorption, there were no significant differences between normal aggregates and RCA. Later, recycled aggregates were introduced in asphalt mixes using either 60/70 bitumen or 80/100 bitumen. In these mixes, natural coarse aggregate was partly (0%, 25%, 50% and 75%) or totally (100%) replaced by recycled aggregates. Replacement results show that the use of recycled aggregates increased the optimum bitumen content of the asphalt mixes. Properties and performance of mixes made from both grades of bitumen were compared. Although the increase of RCA percentage decreased the resilient modulus of the asphalt mixes, it increased their skid resistance. However, 60/70 bitumen increased the resilient modulus and skid resistance of the asphalt mixes compared to 80/100 bitumen. Mixes containing RCA show lower water sensitivity (stripping resistance) than RCA-free mixes. However, replacements up to 50% do not violate the 80% tensile strength ratio limit. Although the 50% replacement limit is acceptable, however, the volumetric properties were violated at this replacement ratio. Therefore, for both grades of bitumen, replacements more than 25% should not be used in hot mix asphalt for heavy traffic pavements.

Effect of using fly ash as alternative filler in hot mix asphalt

Summary This study investigates the effect of using fly ash (FA) in asphalt mixture as replacement of common filler. In view of the same, samples were prepared for different bitumen content (3.5−6.5% at 0.5% increments) by using 2% hydrated lime (HL) in control mix as well as varying percentage of FA ranging from 2 to 8% as alternative filler in modified mixes. The optimum bitumen content (OBC) was then determined for all the mix by Marshall mix design. Experimental results indicated higher stability value with lower OBC for the mixture having 4% FA as optimum filler content in comparison with conventional mix and standard specification. So this study discuss the feasibility of using FA as alternative filler instead of HL in asphalt concrete mix by satisfying the standard specification.

Karakteristik Campuran AC-WC dengan Penambahan Limbah Plastik Low Density Polyethylene (LDPE)

This study aims to determine the effect of using plastic waste Low Density polyethylene ( LDPE ) on the characteristics of a mixture of AC- WC . This study used five plastic content variation is 1 % , 2 % , 3 % , 4 % , and 5 % to determine the characteristics of the AC- WC . The method used in this study is a test that aims marshall know the characteristics , the performance of the mixture , and the optimum level of use of asphalt in the mix AC- WC . The results showed that the characteristic value AC- WC that include the percentage of plastic content obtained from the testing of 1 % -5 % of the optimum bitumen content , if the levels of plastic in bitumen is added, the value of stability , flow , and marshall quotient increase and decrease unstable , while the value of VFB and the density increases, and the value of VIM and VMA decreases.

Pengaruh Penggunaan Abu Sekam Padi sebagai Bahan Pengisi pada Campuran Hot Rolled Asphalt terhadap Sifat Uji Marshall

Rice Husk Ash (RHA) has fairly high content of SiO2 and easily obtainable. It is inexpensive since it is the residual waste of the tile or brick combustion process that is not utilized properly. RHA has the potential to be used as filler in Hot Rolled Asphalt (HRA) since it has high flexibility mixture design. The influential characteristic of RHA is that it has fine aggregate fraction. This study aims to discover the physical properties of RHA, the characteristic of the Marshall test properties, the optimum bitumen content, and the economical comparison between the RHA-mixed HRA and the conventional one using stone dust filler. The results of this study indicate that the use of the RHA is able to increase the optimum bitumen content. In terms of economical comparison, the use of RHA as filler material is much more economical than using stone dust as filler.

A STUDY ON THE MARSHALL PROPERTIES OF DBM MIX PREPARED USING VG-30 AND CRMB-55 AS BINDER MATERIALS

A good bituminous mix design is anticipated to produce a mix which is supposed to be sufficiently sturdy, long-lasting, resistive.DBM is used as a binder course in the highway pavement. Binder is a prime material in the bituminous mix. Marshall properties of bituminous mix varies from binder to binder. In this work an effort has been ended to evaluate the Marshall properties of dense bituminous macadam prepared using VG-30 and CRMB-55 as binder materials. DBM mix is prepared using 2% lime as filler material and VG-30, CRMB-55 as binder material. Marshall method of bituminous mix design is adopted to decide the optimum bitumen content (OBC )and Marshall properties were determined at optimum bitumen content. On the basis of limited laboratory studies carried out, it is conclude that CRMB-55 is superior binder material in terms of Marshall properties.

EFFECT OF GRADATION OF AGGREGATES ON MARSHALL PROPERTIES OF SDBC MIX DESIGN

Semi Dense Bituminous concrete (SDBC) is the upper bituminous layer of the road subjected to moderate traffic loads. The grading of aggregates used to prepare the SDBC mix should fall within the limits specified in MoRTH. For each aggregate fraction there is a specified gradation range with lower and higher limits of aggregates passing through a particular sieve size. The gradation range specified in MoRTH is quite wide. Therefore mix design by adopting a particular gradation of the aggregate falling within the MoRTH range also affects the Marshall properties. The present study is taken to evaluate the Marshall property of SDBC mix prepared using the aggregate having different grading within the grading limits specified by the MoRTH. In order to study this aspect five mixes having different gradation were prepared. The gradation used correspond to Lower Grade (L.G.), Lower Middle Grade (L.M.G.), Middle Grade (M.G.), Higher Middle Grade (H.M.G.), Higher Grade (H.G.) of the gradation range specified by MoRTH . The test result revealed that there is significant variation in Marshall Properties of the mixes having different gradation of the aggregates. The Stability values obtained is maximum for the Lower Middle Grade (L.M.G.) range of MoRTH specification. The Flow values obtained is maximum for the Middle Grade (M.G.).The Optimum Bitumen Content (O.B.C.) is also minimum in Lower Middle Grade (L.M.G.).

A Study on Use of Natural Fiber for Improvement in Engineering Properties of Dense Graded Bituminous Mixes with Coal Ash

Coal-based thermal power plants have been a major source of power generation in India. The prime waste products of a coal based thermal power plant are fly ash and bottom ash. Heavy dumping of these waste products causes fatal environment pollution to air, water, and land, besides impairing human health. This research work is done to explore the optimum use of ash, namely bottom ash (as part of fine aggregate) and fly ash (as mineral filler) along with natural fiber (such as sisal fiber) used to improvise the engineering properties of bituminous paving mixes. In the present laboratory study, dense graded bituminous mix specimens were prepared using natural aggregates as coarse aggregates, bottom ash as fine aggregates, fly ash as filler and sisal fiber as additive. To strengthen the mix, slow setting emulsion (SS1) coated sisal fiber was added in varying percentages such as 0, 0.25, 0.5, 0.75, and 1 % by weight of the mix, with variations of sisal fiber length such as 0, 5, 10, 15 and 20 mm. The most suitable composition (such as optimum bitumen content and optimum fiber content including the optimum length of fiber in the bituminous mix) was selected based on the results of Marshall tests. Further, for justifying the performances of the bituminous paving mix thus developed, tests for indirect tensile strength and moisture susceptibility in the form of tensile strength ratio and retained stability of bituminous mixes were conducted.

Recycling of polyethylene terephthalate (PET) plastic bottle wastes in bituminous asphaltic concrete

AbstractThis research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC) used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%), 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC) for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA)-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC) of 16.7% by weight of...

Effect of using Fibre on the Durability of Asphalt Pavement

Using the fibre additives with a uniform distribution in asphaltic concrete mixture is a well-known technique for improving the mechanical properties and durability of asphalt pavement. The purpose of this study is to investigate the effect of preparing fibre and production of the properties of bitumen and asphalt concrete mixture. In this study, a dense-graded aggregation, mineral fibres (asbestos) and synthetic fibres (polyester and nylon) were used. Laboratory studies were done by comparing different rheological properties, mechanical and moisture susceptibility of mixtures of fibres. Results of the penetration and softening point on mixtures of bitumen – fibre show that fibres improve the mixed rheological properties and stiffening effect of fibre properties. The results of Marshall Tests indicate that adding fibres reduces the strength in Marshall and results in the slight increase in the percentage of optimum bitumen content and asphalt percentage of air voids in comparison with typical fibre. The results of the indirect tensile tests showed that the addition of fibres, depending on the percentage of fibres significantly improves the durability of the mixture.

Utility of polyparaphenylene terephtalamide fiber in hot mix asphalt as a fiber

In this study, utility of polyparaphenylene terephtalamide (PT) was investigated in hot mix asphalt as a fiber. For this aim samples were prepared with limestone aggregate at different proportions. Marshall Stability test was applied and optimum bitumen content was determined. In the second stage of the study, new samples were prepared using different polyparaphenylene terephtalamide fiber (PTF) rates of 0.25%, 0.50%, 0.75%, 1.00%, 1.50%, 2.00% based on optimum bitumen content. When examining test results, samples which prepared using 0.25% PTF rate gave highest Marshall Stability result. At the final stage of the study, different bitumen contents (4.15%, 4.65% and 5.15%) were conducted for the best fiber rate (0.25%) and close to this result (0.50% and 0.75%). Thus, the effect of bitumen content on determined fiber rate at the second stage of the study was investigated. Also Indirect Tensile (IDT) Strength Test was performed on hot mix asphalt (HMA) samples preparing at 0.25%, 0.50% and 0.75% fiber rates and moisture sensitivities were determined. All results showed that, the best fiber rate was 0.25% and determined optimum bitumen content remain constant with the fiber additive for the reference samples. Besides, some sample groups which prepared using different PTF rates proved the specification limits and it was said that; PTF can be used in asphalt concrete as a fiber additive.

New Laboratory Mix Methodology of Microsurfacing and Mix Design

Microsurfacing was introduced in Germany, Spain, and France since 1976 and in the United States in 1980 (NCHRP 411, 2010). In India, it was introduced only in 1999-2000 (Yala construction, 2011) under the brand name, Macroseal by Yala construction and Elsamex SA, Spain. Established mix methodologies (Kharagpur and TxDOT methods) were evaluated and balling appeared to be still present with this method. A different mix methodology was explored and observed to have reduce or solve balling, the common problem of mixing coarse, fine aggregates with emulsion. The mix methodology was developed for type II, and type III gradation for microsurfacing and was adopted for the study. By adopting the mixing methodology, break time, setting times and consistency test were evaluated with variable water content 5%, 7%, 8% 10%. The consistency value observed was between 2cm to 4cm and that microsurfacing of Type II and III satisfies all the criteria given in Technical Bulletin of ISSA.Modified marshal test was also carried out to determine the optimum residual bitumen content. It was found that at 4% air voids the optimum residual bitumen content for Type III gradation is 10% and for Type II gradation is 7.7% and at these optimum contents, flow, air voids, VFB and VMA satisfy the requirement of Marshall Criteria.

Marshall Stability and Flow of Lime-modified Asphalt Concrete

The purpose of highway pavement is to provide smooth surface over which vehicles can move safely from one place to another. The two major types of pavement (flexible and rigid) have been mostly selected for the highway pavement to fulfil this function and they must be capable of transferring the wheel load to the subgrade such that its bearing capacity is not exceeded. However, the flexible pavements normally show defects like rutting, fatigue failure, low skid resistance and so on, causing the pavement to fail before its design life. Therefore, it is important to modify the asphalt concrete to make it more resistant to rutting and fatigue failure. Lime-modified asphalt has been observed to have better resistance to rutting, cracking and stripping, as well as having improved aging behavior. Therefore, this study looks at the Marshall properties of hydrated lime-modified asphalt mixture and the conventional asphalt. The conventional asphalt mixture was made using 10% mineral filler while for the lime-modified asphalt, the mineral filler was replaced with hydrated lime. The bitumen with penetration grade 60/70 was used and the content varied from 5.0 to 7.5%. Marshall stability and flow tests were carried out on the samples. The results show that the Marshall stability for the asphalt concrete with mineral filler ranges from 5.89 – 7.90 kN while that with hydrated lime ranges from 5.9 to 8.2 kN. The flow values for the asphalt concrete with mineral filler range from 2.3 mm – 3.3 mm, while that with hydrated lime range from 2.4 – 3.4 mm. The optimum bitumen content for both mixtures was found to be 6.5%. The stability and flow for the mixture with mineral filler were 7.9 kN and 3.3 mm, respectively, while for the mixtures with hydrated lime they were 8.2 kN and 3.4 mm, respectively. This indicates the replacement of the mineral filler with lime improves the stability of the mixtures, while there was slight increase in the flow of the mixture with hydrated lime. The slight increase in stability and flow values may be attributed to the complete replacement of the mineral filler with lime and the high lime content used in the study. More studies are being carried out to evaluate the Marshall properties for mixture with the mineral filler partially replaced with lime and for varying proportions of the lime content in the asphalt mixture.

Evaluation of Bituminous Concrete Mixture Properties with Steel Slag

This paper presents the utilization of the steel slag which is used as a replacement material for coarse aggregates of different sizes for different bituminous mix i.e. 37.5mm down, 20mm down, 12.5mm down at different percentages. The gradation requirement was fulfilled at all the replacement percentages for the DBM grade-II. A various tests were executed to characterize the physical properties of aggregates, steel slag and bitumen. The chemical tests on steel slag also showed good result. Bituminous mixtures of virgin aggregates and replacement of steel slag were used to prepare Marshall Specimens and to determine optimum bitumen content. Mechanical characteristics of all the mixtures were evaluated by Marshall Stability and Indirect tensile strength tests. It is compared with the mixture containing virgin aggregates. All the mixtures with steel slag have satisfied the MoRT&H standards. It was observed that steel slag used as a coarse aggregate improved the mechanical properties of bituminous mixtures and thus resulting as suitable for use in the construction of road.