Characteristics of Warm Mix Asphalt Incorporating Coarse Steel Slag Aggregates

The major goal of sustainable practices is to preserve raw resources through the utilization of waste materials as an alternative to natural resources. Decreasing the temperature required to produce asphalt mixes contributes to environmental sustainability by reducing energy consumption and toxic emissions. In this study, warm mix asphalt incorporating coarse steel slag aggregates was investigated. Warm mix asphalt was produced at different temperatures lower than the control asphalt mixes (hot mix asphalt) by 10, 20, and 30 °C. The performances of the control and warm mix asphalt were assessed through laboratory tests examining stiffness modulus, dynamic creep, and moisture sensitivity. Furthermore, a response surface methodology (RSM) was conducted by means of DESIGN EXPERT 11 to develop prediction models for the performance of warm mix asphalt. The findings of this study illustrate that producing warm mix asphalt at a temperature 10 °C lower than that of hot mix asphalt exhibited the best results, compared to the other mixes. Additionally, the warm mix asphalt produced at 30 °C lower than the hot mix asphalt exhibited comparable performance to the hot mix asphalt. However, as the production temperature increases, the performance of the warm mix asphalt improves.

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Evaluating the Surface Free Energy and Moisture Sensitivity of Warm Mix Asphalt Binders Using Dynamic Contact Angle

Advances in Civil Engineering ◽

10.1155/2019/9153603 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15 ◽

Cited By ~ 6

Author(s):

Muhammad Rafiq Kakar ◽

Meor Othman Hamzah ◽

Mohammad Nishat Akhtar ◽

Junita Mohamad Saleh

Keyword(s):

Contact Angle ◽

Free Energy ◽

Hot Mix Asphalt ◽

Asphalt Binder ◽

Moisture Damage ◽

Warm Mix Asphalt ◽

Work Of Adhesion ◽

Moisture Sensitivity ◽

Modified Binders ◽

Production Temperature

From the environmental conservation perspective, warm mix asphalt is more preferable compared to hot mix asphalt. This is because warm mix asphalt can be produced and paved in the temperature range 20–40°C lower than its equivalent hot mix asphalt. In terms of cost-effectiveness, warm mix asphalt can significantly improve the mixture workability at a lower temperature and thus reduce greenhouse gas emissions, to be environment friendly. However, the concern, which is challenging to warm mix asphalt, is its susceptibility to moisture damage due to its reduced production temperature. This may cause adhesive failure, which could eventually result in stripping of the asphalt binder from the aggregates. This research highlights the significance of Cecabase warm mix additive to lower the production temperature of warm mix asphalt and improvise the asphalt binder adhesion properties with aggregate. The binders used in the preparation of the test specimen were PG-64 and PG-76. The contact angle values were measured by using the dynamic Wilhelmy plate device. The surface free energy of Cecabase-modified binders was then computed by developing a dedicated algorithm using the C++ program. The analytical measurements such as the spreadability coefficient, work of adhesion, and compatibility ratio were used to analyze the results. The results inferred that the Cecabase improved the spreadability of the asphalt binder over limestone compared to the granite aggregate substrate. Nevertheless, the Cecabase-modified binders improved the work of adhesion. In terms of moisture sensitivity, it is also evident from the compatibility ratio indicator that, unlike granite aggregates, the limestone aggregates were less susceptible to moisture damage.

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Influence of the Production Temperature on the Optimization Process of Asphalt Mixes Prepared with Steel Slag Aggregates Only

Lecture Notes in Civil Engineering - Proceedings of the 5th International Symposium on Asphalt Pavements & Environment (APE) ◽

10.1007/978-3-030-29779-4_21 ◽

2019 ◽

pp. 214-223

Author(s):

Emiliano Pasquini ◽

Giovanni Giacomello ◽

Marta Skaf ◽

Vanesa Ortega-Lopez ◽

Juan Manuel Manso ◽

...

Keyword(s):

Steel Slag ◽

Optimization Process ◽

Asphalt Mixes ◽

Production Temperature

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

Innovative Infrastructure Solutions ◽

10.1007/s41062-021-00528-7 ◽

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.

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Laboratory Investigation of Pavement Backfilling Materials for Micro-Trenching in Cold Regions

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198118784172 ◽

2018 ◽

Vol 2672 (12) ◽

pp. 62-71

Author(s):

Leila Hashemian ◽

Vinicius Afonso Velasco Rios ◽

Alireza Bayat

Keyword(s):

Laboratory Investigation ◽

Dynamic Modulus ◽

Laboratory Tests ◽

Hot Mix Asphalt ◽

Cement Grout ◽

Host Material ◽

High Quality ◽

Cold Temperatures ◽

Asphalt Mixes ◽

Freeze Thaw

This study investigated the performance of different materials in a micro-trench composite backfilling design. Laboratory tests were conducted to evaluate the effect of cold temperatures and freeze/thaw cycles on a cement grout and seven preparatory cold asphalt mixes. To compare the performance of cold mix asphalt and epoxy grout with hot mix asphalt as the host material, rutting tests and dynamic modulus tests at different loading frequencies and temperatures were conducted. Finally, laboratory scale micro-trench samples were prepared using different backfilling materials and were loaded using a wheel tracker after freeze/thaw conditioning. The results showed that cement grout could effectively be used to secure the conduit inside the trench. It was also concluded that using high-quality cold mix asphalt, a compatible material with hot mix asphalt, could improve micro-trench durability compared with epoxy grout.

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Long term performance of warm mix asphalt versus hot mix asphalt

Journal of Central South University ◽

10.1007/s11771-013-1483-1 ◽

2013 ◽

Vol 20 (1) ◽

pp. 256-266 ◽

Cited By ~ 17

Author(s):

Ziari Hasan ◽

Behbahani Hamid ◽

Izadi Amir ◽

Nasr Danial

Keyword(s):

Hot Mix Asphalt ◽

Warm Mix Asphalt ◽

Long Term Performance ◽

Term Performance

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Economic and environmental impact study of warm mix asphalt compared to hot mix asphalt

Journal of Cleaner Production ◽

10.1016/j.jclepro.2015.10.077 ◽

2016 ◽

Vol 112 ◽

pp. 2308-2317 ◽

Cited By ~ 64

Author(s):

Ana Almeida-Costa ◽

Agostinho Benta

Keyword(s):

Environmental Impact ◽

Hot Mix Asphalt ◽

Warm Mix Asphalt ◽

Impact Study ◽

Environmental Impact Study

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LOW CYCLE FATIGUE BEHAVIOR AND LIFE PREDICTION OF A CAST COBALT-BASED SUPERALLOY

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512003261 ◽

2012 ◽

Vol 06 ◽

pp. 251-256

Author(s):

HO-YOUNG YANG ◽

JAE-HOON KIM ◽

KEUN-BONG YOO

Keyword(s):

Fatigue Life ◽

Strain Energy ◽

Life Prediction ◽

Prediction Models ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Total Strain ◽

Cycle Fatigue ◽

Total Strain Range ◽

Different Temperatures

Co -base superalloys have been applied in the stationary components of gas turbine owing to their excellent high temperature properties. Low cycle fatigue data on ECY-768 reported in a companion paper were used to evaluate fatigue life prediction models. In this study, low cycle fatigue tests are performed as the variables of total strain range and temperatures. The relations between plastic and total strain energy densities and number of cycles to failure are examined in order to predict the low cycle fatigue life of Cobalt-based super alloy at different temperatures. The fatigue lives is evaluated using predicted by Coffin-Manson method and strain energy methods is compared with the measured fatigue lives at different temperatures. The microstructure observing was performed for how affect able to low-cycle fatigue life by increasing the temperature.

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Performance Evaluation of Hot Mix Asphalt with Different Proportions of RAP Content

E3S Web of Conferences ◽

10.1051/e3sconf/20183401026 ◽

2018 ◽

Vol 34 ◽

pp. 01026

Author(s):

Ahmad Kamil Arshad ◽

Haryati Awang ◽

Ekarizan Shaffie ◽

Wardati Hashim ◽

Zanariah Abd Rahman

Keyword(s):

Hot Mix Asphalt ◽

Resilient Modulus ◽

Design Method ◽

Asphalt Pavement ◽

Cost Savings ◽

Volumetric Analysis ◽

Public Works ◽

Asphalt Binders ◽

Moisture Susceptibility ◽

Asphalt Mixes

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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