scholarly journals Development of a Semirigid Pavement Incorporating Ultrarapid Hardening Cement and Chemical Admixtures for Cement Grouts

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Jin Wook Bang ◽  
Byung Jae Lee ◽  
Yun Yong Kim
Keyword(s):  
Asphalt Pavement ◽  
Mechanical Tests ◽  
Flow Time ◽  
Cement Grout ◽  
Test Results ◽  
Constant Condition ◽  
Chemical Admixtures ◽  
Mixing Proportion ◽  
Marshall Stability ◽  
Wheel Tracking

Mechanical tests were carried out to evaluate the influence and effects of fluidity and compressive strength of cement grout on semirigid asphalt pavement. An open graded asphalt skeleton was designed in order to achieve target porosity in the range of 18~22%. In addition, four types of cement grout mixtures were produced with varying mix proportions with ultrarapid hardening cement and chemical admixtures, that is, accelerating and retarding agents. For the semirigid pavement specimens, mechanical experiments to measure properties such as porosity, flexural strength, Marshall stability, and wheel tracking resistance were carried out. The test results demonstrated that the flow time (fluidity) of cement grout is the most significant factor that determines the mechanical properties of semirigid asphalt specimens under constant condition of the open graded asphalt skeleton. For the semirigid pavement mixing proportion in the current study, it is recommended that the porosity of the open graded asphalt skeleton and flow time of cement grout should be 20% and within 12 seconds, respectively.

scholarly journals PROPERTIES OF WMA–FOAM MIXES BASED ON MAJOR MECHANICAL TESTS / ŠILTAI MAIŠYTO ASFALTO MIŠINIŲ, GAMINAMŲ PAGAL PUTOTO BITUMO TECHNOLOGIJĄ (WMA-FOAM), SAVYBĖS REMIANTIS PAGRINDINIAIS MECHANINIAIS BANDYMAIS

2011 ◽  
Vol 17 (2) ◽  
pp. 207-216 ◽  
Author(s):  
Amir Kavussi ◽  
Leila Hashemian
Keyword(s):  
Hydrated Lime ◽  
Mechanical Tests ◽  
Moisture Susceptibility ◽  
Adhesion Properties ◽  
Different Temperatures ◽  
Indirect Tensile ◽  
Lime Powder ◽  
Marshall Stability ◽  
Wheel Tracking ◽  
Lower Production

One of the main advantages of warm mix asphalt (WMA) used as an alternative to conventional hot mix asphalt (HMA), is to reduce mixing and compaction temperatures. This laboratory study was conducted with the aim of determining physical properties of WMA mixes produced using foam bitumen technology (WMA–Foam), while applying different mixing and compaction temperatures. The effect of laboratory compaction method on mix properties was also investigated. WMA–Foam mixes were produced, adding a soft bitumen to coarse aggregate particles at the first stage, then a hard bitumen, transformed into foam bitumen using a laboratory foam making device, was directly added to aggregates at the next stage. Compaction was performed separately applying both Marshall and gyratory compactors (GC) at different temperatures. Marshall Stability and void contents of the samples were determined as two major parameters for characterizing WMA–Foam mixes. Moisture susceptibility and rutting potential of WMA–Foam samples were evaluated using indirect tensile strength (ITS) and wheel tracking tests. In addition, separate samples were prepared, in which hydrated lime powder was added as an anti-stripping agent to improve adhesion properties of the mixes. Comparing the results of WMA–Foam mixes with control HMA of the same content, resulted in mixes with similar properties of the control HMA, with appreciably lower production and compaction temperatures of the former. It was also resulted that mixes compacted with gyratory compactor were less sensitive to temperature variations than those compacted with Marshall Hammer. Santrauka Pagrindinis šiltai maišyto asfalto mišinių privalumas, lyginant su įprastiniais karštai maišyto asfalto mišiniais, yra galimybė sumažinti asfalto mišinio maišymo ir tankinimo temperatūras. Šio laboratorinio tyrimo tikslas – nustatyti šiltai maišyto asfalto mišinių, gaminamų pagal putoto bitumo technologiją (WMA-Foam), fizines savybes taikant skirtingas maišymo ir tankinimo temperatūras. Taip pat buvo tirtas skirtingų laboratorinių tankinimo metodų poreikis asfalto mišinio savybėms. WMA-Foam technologijos mišiniai gaminti pirmame etape į stambiąsias mineralines medžiagas dedant minkštąjį bitumą, o kitame etape – kietajį bitumą specialiu laboratoriniu putojimo įrenginiu pavertus putotu bitumu dedant į pirmame etape paruoštas mineralines medžiagas. Tankinta atskirai Maršalo plūktuvu ir giratoriaus presu skirtingose mišinio temperatūrose. Maršalo bandinių pastovumas ir oro tuštumų skaičius buvo nustatyti kaip du pagrindiniai WMA-Foamtechnologijos mišinius charakterizuojantys parametrai. WMA-Foam technologijos bandinių jautrumas vandeniui ir atsparumas provėžų susidarymui buvo vertinti pagal netiesioginio tempimo jėgos ir rato riedėjimo vėžės nustatymo bandymus. Keletas bandinių papildomai buvo pagaminti su gesintosiomis kalkėmis, t. y. asfalto mišinio sukibimą gerinančiu priedu. Lyginant WMA-Foam technologijos ir karštai maišyto asfalto mišinių bandymų rezultatus nustatyta, kad identiškos sudėties WMA-Foam technologijos mišinių savybės yra panašios į karštai maišyto asfalto mišinių savybes, tačiau jos pasiekiamos pastebimai žemesnėse maišymo ir tankinimo temperatūrose. Taip pat nustatyta, kad asfalto mišinio bandiniai, pagaminti giratoriaus presu, buvo ne tokie jautrūs gamybos temperatūros kitimui, lyginant su bandiniais, pagamintais Maršalo plūktuvu.

Suitability of Asphalt Pavement Analyzer for Predicting Pavement Rutting

2000 ◽  
Vol 1723 (1) ◽  
pp. 107-115 ◽  
Author(s):  
Bouzid Choubane ◽  
Gale C. Page ◽  
James A. Musselman
Keyword(s):  
Performance Prediction ◽  
Field Data ◽  
Asphalt Pavement ◽  
Evaluation Process ◽  
Field Measurements ◽  
Asphalt Mixtures ◽  
Test Results ◽  
Asphalt Mixes ◽  
Tracking Device ◽  
Wheel Tracking

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.

scholarly journals Evaluation of Fatigue Potential for Crumb Rubber Modified Bitumen in Stone Mastic Asphalt Mixes

2021 ◽  
Vol 10 (3) ◽  
pp. 170-183
Author(s):  
Anusha T M ◽  
◽  
Sharath Kumar M D ◽  
Dr. H S Jagadeesh ◽  
◽  
...  
Keyword(s):  
Tensile Strength ◽  
Fatigue Test ◽  
Asphalt Pavement ◽  
Indirect Tensile Strength ◽  
Engine Oil ◽  
Reclaimed Asphalt Pavement ◽  
Test Results ◽  
Reclaimed Asphalt ◽  
Indirect Tensile ◽  
Marshall Stability

SMA is a gap graded mix composed of a high concentration of coarse aggregate that is held together in a thick asphalt film by a matrix of mineral filler and stabilizers. Since natural aggregates have become expensive, hence Reclaimed Asphalt Pavement (RAP) can be reused in pavement construction to reduce the environmental hazardous due to disposal problems. Since the RAP contains used aggregates, it is highly prone to fatigue, thermal and reflective cracking effect. Rheological and chemical properties of aged bitumen in RAP can be enhanced by use of untreated waste oils such as waste engine oil as rejuvenators. This research presents a study on fatigue performance of SMA mix with Reclaimed Asphalt Pavement (RAP) materials with and without rejuvenators and results were compared with conventional SMA mix. The materials used were first characterized by common laboratory tests. Then the three SMA mixes are tested using several laboratory test procedures: Marshall Stability, indirect tensile strength, moisture susceptibility, and indirect tension fatigue test. The optimum proportions of the of the mixes with highest stability are selected from the Marshall stability test. The indirect tensile strength test results show that the SMA mix replaced with RAP without rejuvenators showed higher tensile strength ratio and resistance to moisture damage when compared to conventional mix and optimum RAP replacement mix with rejuvenators. The fatigue test was conducted for the three optimum mixes at different temperature and stresses. The fatigue test results showed that at lower temperature and stresses, the RAP replaced SMA without rejuvenator offered better fatigue resistance than those with rejuvenator and conventional SMA mix. At higher temperatures, the RAP replaced SMA mix with rejuvenator offered similar fatigue lifecycle as conventional mix. However, at high stresses, conventional SMA mix offered better fatigue lifecycle. Increase in failure stresses resulted in decrease of number of fatigue cycles and increased in initial tensile strain of the mix. Thus, with the use of RAP substantial decrease in cost can be achieved without compromising the fatigue characteristic of the SMA mix.

scholarly journals Performance Evaluation of Semiplastic Recycled Cold Asphalt Using Noncement Binders

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Byung Jae Lee ◽  
Jin Wook Bang ◽  
Jeong Su Kim ◽  
Young Il Jang
Keyword(s):  
Mass Loss Rate ◽  
Strength Increase ◽  
Test Results ◽  
Asphalt Emulsion ◽  
Time Strength ◽  
Mixing Proportion ◽  
Residual Stability ◽  
Marshall Stability ◽  
Emulsified Asphalt ◽  
Optimal Mixing

The optimal mixing conditions for semiplastic recycled cold asphalt, which recycled waste asphalt and used noncement binders (NCB), were assessed through verification of the performance. The NCB of 6% desulfurization gypsum mixing was found to have the most outstanding properties. For the Marshall stability, 4% (NCB) filler mixing brought about a 1.92-time strength increase effect compared to OPC (2%) and was improved when using modified asphalt and SBR. The flow test results showed that although an increase dosage of filler and SBR decreased the flow value of the semiplastic recycled cold asphalt, an increase dosage of asphalt emulsion improved the flow value. The indirect tensile strength and liquid immersion residual stability for the condition with greatest Marshall stability were most outstanding with 0.95 MPa and 83.6%, respectively. Evaluation of the recycled cold asphalt abrasion durability revealed that for the case of mixing more than 4% NCB the mass loss rate was lower than 20%. The abrasion durability was found to improve when using modified emulsified asphalt and SBR substitution. From the test results, it was found that the optimal mixing proportion of semiplastic recycled cold asphalt satisfied mechanical properties and durability is NCB with 4%, emulsified asphalt with 3%, and SBR substitution with 20%.

scholarly journals DAUR ULANG RECLAIMED ASPHALT PAVEMENT SEBAGAI BAHAN UTAMA CAMPURAN BETON ASPAL EMULSI UNTUK LAPIS PERMUKAAN

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Anni Susilowati ◽  
Andhika Kesuma
Keyword(s):  
Asphalt Concrete ◽  
Hot Mix Asphalt ◽  
Asphalt Pavement ◽  
Heavy Traffic ◽  
Reclaimed Asphalt Pavement ◽  
Road Maintenance ◽  
Reclaimed Asphalt ◽  
Asphalt Content ◽  
Marshall Stability ◽  
Wheel Tracking

ABSTRACTReclaimed Asphalt Pavement (RAP) material as a result of road maintenance by Scrapping-Filling-Overlay method is a waste material which had potential to be recovered as a surface layerof road. The maintenance in highway road of Indonesia used hot mix asphalt in general. But, hot mix asphalt are not environmentally friendly and makes energy wasting because it needs burning process at mixing. Those things are the main causes of this research. This asphalt concrete with RAP with cold mixing is expected to fulfill the requirements of asphalt concrete for heavy traffic. In this research is asphalt content variations at 6,5; 7,0; 7,5; 8,0; and 8,5% to total mixture. The results of this research shows that the highest Marshall stability could not reach minimum value of heavy loaded traffic, that is at emulsion asphalt content 7% only for 711 kg. Besides, the percentage of void in mixture (VIM), void filled with bitumen (VFB) and flow couldn’t fulfill the specification of SNI 8198:2015. With the result that optimum asphalt content cannot be obtained. Result of wheel tracking test could not be obtained too because the specimens collapse during the test.Key words : Emulsion asphalt, Reclaimed Asphalt Pavement, stability, Wheel Tracking MachineABSTRAKMaterial Reclaimed Asphalt Pavement (RAP) hasil dari pemeliharaan dengan metode Scrapping-Filling Overlay merupakan limbah yang berpotensi untuk dimanfaatkan kembali menjadi lapis permukaan. Pada umumnya penanganan jalan di Indonesia menggunakan campuran panas. Namun, campuran panas kurang ramah lingkungan dan tidak hemat energi. Karena membutuhkan proses pembakaran dalam proses pencampuran. Hal ini yang menjadi alasan utama penelitian ini. Beton aspal dengan bahan utama RAP dengan campuran dingin ini diharapkan mampu memenuhi syarat lapisan aspal beton untuk lalu lintas berat. Variasi pada penelitian ini adalah kadar aspal 6,5; 7,0; 7,5; 8,0; dan 8,5% terhadap total campuran. Hasil dari penelitian menunjukan bahwa stabilitas Marshall tertinggi tidak mampu mencapai nilai minimum untuk lalu lintas berat, yaitu pada kadar aspal emulsi 7% hanya sebesar 711 kg. Selain itu prosentase rongga dalam campuran (VIM), rongga terisi aspal (VFB) serta kelelehan tidak memenuhi spesifikasi dari SNI 8198:2015. Sehingga, kadar aspal optimum tidak didapatkan. Hasil dari pengujian alur roda juga tidak didapatkan karena benda uji amblas ketika pengujian dilakukan.Kata kunci : Aspal emulsi, Reclaimed Asphalt Pavement, stabilitas, Wheel Tracking Machine

scholarly journals Rutting and moisture-induced damage potential of foamed warm mix asphalt (WMA) containing RAP

2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Mohammad Ashiqur Rahman ◽  
Rouzbeh Ghabchi ◽  
Musharraf Zaman ◽  
Syed Ashik Ali
Keyword(s):  
Asphalt Pavement ◽  
Warm Mix Asphalt ◽  
Environmental Benefits ◽  
Reclaimed Asphalt Pavement ◽  
Chemical Additives ◽  
Flow Number ◽  
Damage Potential ◽  
Asphalt Mixes ◽  
Reclaimed Asphalt ◽  
Wheel Tracking

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.

Medium Density Particleboard with Addition of Impregnated Paper

2014 ◽  
Vol 1025-1026 ◽  
pp. 543-546
Author(s):  
Juliana Cortez Barbosa ◽  
Anderson Luiz da Silva Michelon ◽  
Elen Aparecida Martines Morales ◽  
Cristiane Inácio de Campos ◽  
André Luis Christoforo ◽  
...  
Keyword(s):  
Moisture Content ◽  
Modulus Of Elasticity ◽  
Mechanical Tests ◽  
Modulus Of Rupture ◽  
Medium Density ◽  
Test Results ◽  
Thickness Swelling ◽  
Adhesion Test ◽  
Layer Medium ◽  
Determine Moisture Content

The aim of this research was to produce three-layer Medium Density Particleboard (MDP), with the addition of impregnated paper, in the inner layer, in proportions of 1; 5 and 20%. In this study, MDP was composed with particles of small size in outer layers, and larger particles in internal layer. After panel manufacturing, physical and mechanical tests based on Brazilian Code ABNT NBR 14.810 were carried out to determine moisture content; density; thickness swelling; water absorption; modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending and internal adhesion. Test results were compared to commercial panels, produced with 100% Eucalyptus, considering the requirements specified by Brazilian Code. Properties presented values close to normative specifications, indicating positively the possibility of production of MDP using addition of waste paper impregnated.

Determining Optimum Carbon Nanotubes Content for Asphalt Mixture in Road Pavements

2021 ◽  
Vol 1023 ◽  
pp. 121-126
Author(s):  
Van Bach Le ◽  
Van Phuc Le
Keyword(s):  
Carbon Nanotubes ◽  
Asphalt Pavement ◽  
Asphalt Binder ◽  
Asphalt Mixture ◽  
Construction Cost ◽  
Asphalt Mixtures ◽  
Static Modulus ◽  
Pavement Construction ◽  
Modified Binder ◽  
Marshall Stability

Although small amount of binder in asphalt concrete mixture may commonly range from 3.5 to 5.5% of total mixture as per many international specifications, it has a significant impact on the total cost of pavement construction. Therefore, this paper investigated the effects of five carbon nanotubes contents of 0.05%, 0.1%, 0.15%, 0.2%, 0.25% by asphalt weight as an additive material for binder on performance characteristics of asphalt mixtures. Performance properties of CNTs modified asphalt mixtures were investigated through the Marshall stability (MS) test, indirect tensile (IDT) test, static modulus (SM) test, wheel tracking (WT) test. The results indicated that asphalt mixtures with CNT modified binder can improve both the rutting performance, IDT strength and marshall stability of tested asphalt mixtures significantly at higher percentages of carbon nanotubes. However, the issue that should be considered is the construction cost of asphalt pavement. Based on the asphalt pavement structural analysis and construction cost, it can be concluded that an optimum CNT content of 0.1% by asphalt weight may be used as additive for asphalt binder in asphalt mixtures.

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.

Rheological Flow Study of Molten Weld Metal Using the Modified Casson Prediction Model

2011 ◽  
Vol 403-408 ◽  
pp. 491-495
Author(s):  
Joseph I Achebo
Keyword(s):  
Shear Stress ◽  
Weld Metal ◽  
Prediction Model ◽  
Mechanical Test ◽  
Mechanical Tests ◽  
Test Results ◽  
Upward Flow ◽  
Viscoplastic Flow ◽  
Flow Equations ◽  
Flow Study

This paper principally examines the flow pattern that occurs when molten weld metal droplets are detached from globule formations at the tip of an electrode and are thereafter transported to the weldpool. This viscoplastic flow study was done using the modified Casson prediction model which is based on the Newtonian Homogenous Flow equations. Both chemical and mechanical tests were done. The inclusions (Slag) were found to possess an upward flow of 3 ms-1. The mechanical test results show that the shear stress of 483.2 MPa, which exceeded a yield stress of 230 MPa, was responsible for the continuous slipping movement of the molten metal towards the center of the weld pool at a velocity of 1.2ms-1. The results obtained by the application of this model were validated by both computational and experimental results obtained by other researchers.

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