scholarly journals Mechanical performance of intelligent asphalt mixture utilizing rejuvenator encapsulated method

2020 ◽  
Vol 15 (55) ◽  
pp. 187-197
Author(s):  
Sari Sharif Ali ◽  
Mahyar Arabani ◽  
Hassan Latifi
Keyword(s):  
Mechanical Performance ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Thermal Gravimetric ◽  
Tensile Fatigue ◽  
The Matrix ◽  
Successful Technique ◽  
Indirect Tensile ◽  
Encapsulation Method ◽  
Mixture Samples

In this study, in order to evaluate the effects of heavy vacuum slops (H.V.S) as rejuvenator and nano-Zycosil as an anti-stripping agent on used encapsulation method and mechanical performance of asphalt mixture samples, scanning electron microscopy (SEM), computerized tomography (CT) scan and thermal gravimetric (TG) analyses and also, indirect tensile strength (ITS) and indirect tensile fatigue (ITF) tests were performed. First, an encapsulation procedure to prepare different specimens including modified and unmodified samples with nano-Zycosil was done. In the following, morphology of the nano-Zycosil-modified capsules and aggregates were particularly evaluated. Considering the morphology evaluation and TG analysis diagrams, it was found that most of the capsules resisted the mixing procedure of the asphalt mixture. So, the encapsulation procedure used in this study was a successful technique. In addition, modification with nano-Zycosil as an anti-stripping agent significantly improved the adhesion strength in the matrix of capsules-aggregates-asphalt binder by converting the adhesion type from silanolian to siloxane. Overall, modification of capsules and main aggregates together with nano-Zycosil significantly improved moisture resistance and mechanical performance of asphalt mixture samples.

scholarly journals MECHANICAL PERFORMANCE OF ASPHALT MIXTURE CONTAINING CUP LUMP RUBBER

2019 ◽  
Vol 81 (6) ◽  
Author(s):  
Norfazira Mohd Azahar ◽  
Norhidayah Abdul Hassan ◽  
Ramadhansyah Putra Jaya ◽  
Hasanan Md. Nor ◽  
Mohd Khairul Idham Mohd Satar ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
Resilient Modulus ◽  
Permanent Deformation ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Modified Asphalt ◽  
Dynamic Creep ◽  
Aging Conditions ◽  
Public Work Department ◽  
Indirect Tensile

The use of cup lump rubber as an additive in asphalt binder has recently become the main interest of the paving industry. The innovation helps to increase the natural rubber consumption and stabilize the rubber price. This study evaluates the mechanical performance of cup lump rubber modified asphalt (CMA) mixture in terms of resilient modulus, dynamic creep and indirect tensile strength under aging conditions. The CMA mixture was prepared using dense-graded Marshall-designed mix and the observed behavior was compared with that of conventional mixture. From the results, both mixtures passed the volumetric properties as accordance to Malaysian Public Work Department (PWD) specification. The addition of cup lump rubber provides better resistance against permanent deformation through the enhanced properties of resilient modulus and dynamic creep. Furthermore, the resilient modulus of CMA mixture performed better under aging conditions.  

scholarly journals Assessments on the Performance of Asphalt Mixtures Prepared with Adhesion Promoters

2019 ◽  
Vol 8 (3S3) ◽  
pp. 332-339
Keyword(s):  
Mechanical Performance ◽  
Water Immersion ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Adhesion Promoters ◽  
Modified Asphalt ◽  
Service Characteristics ◽  
Bonding Properties ◽  
Mechanical Performances

Asphalt pavement is typically susceptible to moisture damage. However, it could be improved with the incorporation of additives or modifiers through binder modifications. The objective of the study is to assess the effect of adhesion promoters, namely PBL and M5000, onto the Hot Mix Asphalt (HMA). The performance of asphalt mixture has been assessed in terms of the service characteristics, the bonding properties, and mechanical performances. The service characteristics were assessed through the Workability Index (WI) and Compaction Energy Index (CEI) to evaluate the ease of asphalt mixture during the mixing and compaction stage. The bonding properties of the modified asphalt mixtures were determined using the boiling water test and static water immersion test to signify the degree of coating after undergoing specific conditioning period and temperature. The mechanical performances of the modified asphalt mixture were evaluated via Marshall stability, semi-circular bending, and modified Lottman tests. All specimens were prepared by incorporating adhesion promoters at the dosage rates of 0.5% and 1.0% by weight of asphalt binder. From the investigation, the bonding properties significantly improved for the modified asphalt mixture compared to the control mixture. The WI of the modified asphalt mixture increased while the CEI decreased in comparison to the control specimen. This implies the workability of modified asphalt mixture is better and requires less energy to be compacted. Modified asphalt mixture generally had better mechanical performance. Therefore, it can be deduced that the asphalt mixture with adhesion promoters have better overall performance than the control mixture.

Effectiveness of Loaded Wheel Tracking Test to Ascertain Moisture Susceptibility of Asphalt Mixtures

2021 ◽  
pp. 036119812110363
Author(s):  
Moses Akentuna ◽  
Louay N. Mohammad ◽  
Sanchit Sachdeva ◽  
Samuel B. Cooper ◽  
Samuel B. Cooper
Keyword(s):  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Moisture Damage ◽  
Asphalt Mixtures ◽  
Asphalt Binders ◽  
Creep Recovery ◽  
Moisture Susceptibility ◽  
Freeze Thaw ◽  
Wheel Tracking ◽  
Mixture Samples

Moisture damage of asphalt mixtures is a major distress affecting the durability of asphalt pavements. The loaded wheel tracking (LWT) test is gaining popularity in determining moisture damage because of its ability to relate laboratory performance to field performance. However, the accuracy of LWT’s “pass/fail” criteria for screening mixtures is limited. The objective of this study was to evaluate the capability of the LWT test to identify moisture susceptibility of asphalt mixtures with different moisture conditioning protocols. Seven 12.5 mm asphalt mixtures with two asphalt binder types (unmodified PG 67-22 and modified PG 70-22), and three aggregate types (limestone, crushed gravel, and a semi-crushed gravel) were utilized. Asphalt binder and mixture samples were subjected to five conditioning levels, namely, a control; single freeze–thaw-; triple freeze–thaw-; MiST 3500 cycles; and MiST 7000 cycles. Frequency sweep at multiple temperatures and frequencies, and multiple stress creep recovery tests were performed to evaluate asphalt binders. LWT test was used to evaluate the asphalt mixture samples. Freeze–thaw and MiST conditioning resulted in an increase in stiffness in the asphalt binders as compared with the control. Further, freeze–thaw and MiST conditioning resulted in an increase in rut depth compared with the control asphalt mixture. The conditioning protocols evaluated were effective in exposing moisture-sensitive mixtures, which initially showed compliance with Louisiana asphalt mixture design specifications.

Expansion Level of Steel Slag Aggregate Effects on Both Material Properties and Asphalt Mixture Performance

2019 ◽  
Vol 2673 (3) ◽  
pp. 506-515 ◽  
Author(s):  
Jamilla Emi Sudo Lutif Teixeira ◽  
Aecio Guilherme Schumacher ◽  
Patrício Moreira Pires ◽  
Verônica Teixeira Franco Castelo Branco ◽  
Henrique Barbosa Martins
Keyword(s):  
Material Properties ◽  
Mechanical Performance ◽  
Early Stage ◽  
Asphalt Binder ◽  
Steel Slag ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Mix Design ◽  
Expansion Level ◽  
Different Levels

The influence of steel slag expansion level on the early stage performance of hot mix asphalt (HMA) is evaluated. Initially, samples of Linz-Donawitz type steel slag with different levels of expansion (6.71%, 3.16%, 1.33%) were submitted to physical, mechanical, and morphological characterization to assess the effects of expansion on individual material properties. Steel slag was then used as aggregate in HMA to verify the effects of its expansion characteristics on the volumetric and mechanical performance of the asphalt mixture. Four different asphalt mixtures were designed based on Marshall mix design, using asphalt cement (pen. grade 50/70), natural aggregate (granite), and steel slag (in three different levels of expansion). The mechanical characteristics of the asphalt mixture were evaluated based on results from Marshall stability, indirect tensile strength, and resilient modulus testing. A modified Pennsylvania testing method (PTM) was also performed on the studied asphalt mixtures to verify the potential of asphalt binder film to minimize the expansive reactions of steel slag. It was observed that the level of steel slag expansion changes some of the material’s individual properties, which can affect the volumetric parameters of the mix design. The use of steel slag as aggregate in HMA also improves the mechanical properties of non-aged asphalt mixtures. Moreover, the expansive characteristics of this material could be minimized when combined with other asphalt mixture components.

scholarly journals Indirect Tensile Test as a Simple Method for Rut Resistance Evaluation of Asphalt Concrete

2019 ◽  
Vol 65 (3) ◽  
pp. 31-44 ◽  
Author(s):  
P. Zieliński
Keyword(s):  
Asphalt Mixture ◽  
Correlation Coefficients ◽  
Simple Method ◽  
Indirect Tensile Test ◽  
Technical Requirements ◽  
Regression Functions ◽  
Indirect Tensile ◽  
Prediction Limits ◽  
Wheel Tracking ◽  
Mixture Samples

AbstractThe paper presents the dependence of ITS results at the elevated temperature (40°C) on rutting parameters, i.e. proportional rut depth (PRDAIR) and wheel tracking speed (WTSAIR), obtained at the temperature of 60°C. The asphalt mixture samples were prepared in the gyratory compactor, but ITS tests were conducted with typical Marshall press, at a loading rate of 50 mm/min. Correlation analyses show a strong relationships between ITS results and rutting parameters, whereby the correlation coefficients obtained are higher for the PRDAIR parameter (r = −0.88) than WTSAIR (r = −0.81). Using the obtained regression functions, the prediction limits as well as confidence limits were calculated, which allowed to develop criteria for assessing resistance to rutting on the basis of ITS test, and taking into account the technical requirements in Poland.

A Three-Dimensional Aggregate Generation and Packing Algorithm for Modeling Asphalt Mixture with Graded Aggregates

2010 ◽  
Vol 26 (2) ◽  
pp. 165-171 ◽  
Author(s):  
R. Xu ◽  
X.H. Yang ◽  
A.Y. Yin ◽  
S.F. Yang ◽  
Y. Ye
Keyword(s):  
Elastic Properties ◽  
Uniaxial Compression ◽  
Mechanical Performance ◽  
Asphalt Mixture ◽  
Three Dimensional ◽  
Packing Algorithm ◽  
Aggregate Base ◽  
Aggregate Shape ◽  
Mixture Samples ◽  
Convex Control

AbstractA three-dimensional aggregate generation and packing algorithm applicable for modeling asphalt mixture with high content of graded aggregates is presented in this paper. In the algorithm, arbitrary-shaped polyhedra are used to model aggregates, so that the effect of aggregate shape on the mechanical performance of asphalt mixture can be considered. The algorithm consists of two steps: Aggregate generation and packing. Polyhedra are created by extending triangular fundaments and treated as visualized aggregates after passing through convex control and sharpness judgment. After that, graded aggregates are taken out from the aggregate base and randomly packed in a given cylindrical or cubical region one by one equiprobably. Overlapping between nearby aggregates is avoided by the help of Boolean partition operation in ANSYS. Finally, some asphalt mixture samples with a given gradation are modeled as examples, and their effective elastic properties and creep behaviors under uniaxial compression are simulated.

scholarly journals Evaluation of Fatigue Life of CRM-Reinforced SMA and Its Relationship to Dynamic Stiffness

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Nuha Salim Mashaan ◽  
Mohamed Rehan Karim ◽  
Mahrez Abdel Aziz ◽  
Mohd Rasdan Ibrahim ◽  
Herda Yati Katman ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Fatigue Test ◽  
Resilient Modulus ◽  
Dynamic Stiffness ◽  
Asphalt Mixture ◽  
Fatigue Cracking ◽  
Crumb Rubber ◽  
Fatigue Properties ◽  
Tensile Fatigue ◽  
Indirect Tensile

Fatigue cracking is an essential problem of asphalt concrete that contributes to pavement damage. Although stone matrix asphalt (SMA) has significantly provided resistance to rutting failure, its resistance to fatigue failure is yet to be fully addressed. The aim of this study is to evaluate the effect of crumb rubber modifier (CRM) on stiffness and fatigue properties of SMA mixtures at optimum binder content, using four different modification levels, namely, 6%, 8%, 10%, and 12% CRM by weight of the bitumen. The testing undertaken on the asphalt mix comprises the dynamic stiffness (indirect tensile test), dynamic creep (repeated load creep), and fatigue test (indirect tensile fatigue test) at temperature of 25°C. The indirect tensile fatigue test was conducted at three different stress levels (200, 300, and 400 kPa). Experimental results indicate that CRM-reinforced SMA mixtures exhibit significantly higher fatigue life compared to the mixtures without CRM. Further, higher correlation coefficient was obtained between the fatigue life and resilient modulus as compared to permanent strain; thus resilient modulus might be a more reliable indicator in evaluating the fatigue life of asphalt mixture.

scholarly journals Impact of Rejuvenators Type on Physical Properties of Aged Asphalt Cement

2019 ◽  
Vol 5 (9) ◽  
pp. 2058-2069 ◽  
Author(s):  
Rana Khaled Hamdan ◽  
Saad Issa Sarsam
Keyword(s):  
Asphalt Concrete ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Accelerated Aging ◽  
Crumb Rubber ◽  
Asphalt Cement ◽  
Punch Test ◽  
Indirect Tensile ◽  
Improved Performance ◽  
Limestone Dust

Recycling can be considered as one of the measures of sustainable methods. The physical traits of the asphalt mixture under the influence of accelerated aging (Long and Short–Term) for asphalt concrete were assessed. Asphalt cement (40-50), aggregate with 12.5 mm nominal extreme size and limestone dust as filler of the mineral was used for the preparation of asphalt concrete mixture. At the optimum content of the asphalt and asphalt of 0.5 percent below and above the optimum value, specimens were prepared by using Marshall Method. Two types of polymers as recycling agents were used (Polyethylene of Low Density and Crumb Rubber) with (0.5, 1 and 1.5) % by weight of the binder. The indirect tensile test was used for the mixtures at 25 ºC and double punch test at 60 ºC. It was determined that the use of (asphalt binder mixed with rubber) as the agent of recycling showed improved performance than the other kind of recycling agent. The indirect tensile strength at 40 ˚C of the recycled mixture was higher than that the control mixture. Punching shear strength was decreased by 84 %, temperature susceptibility was decreased by 69.6 % and the resistance to moisture damage increases by3.3 % at optimum asphalt content.

Sign in / Sign up

Export Citation Format

Share Document