scholarly journals Analysis of stiffness and fatigue resistance of cold recycled asphalt mixtures manufactured with foamed bitumen for their application to airfield pavement design

2017 ◽  
Vol 7 (080) ◽  
pp. 127 ◽  
Author(s):  
H. I. Lacalle-Jiménez ◽  
J. P. Edwards ◽  
N. H. Thom
Keyword(s):  
Fatigue Tests ◽  
Pavement Design ◽  
Raw Material ◽  
Control Mode ◽  
Recycled Asphalt ◽  
Stiffness Modulus ◽  
Reclaimed Asphalt ◽  
Tensile Fatigue ◽  
Indirect Tensile ◽  
Foamed Bitumen

Cold recycled bound materials (CRBMs) provide an economic and environmental advantage for pavements since they decrease energy and raw material consumption. However, design methods for airfield pavements do not include key CRBM properties. In this paper an empirical-mechanistic method is used to study airfield pavement design with CRBM in order to develop design guidance. The aim of the paper is to obtain the inputs related to material properties needed for use in this method. For this purpose, CRBM containing reclaimed asphalt, with fly ash, cement and foamed bitumen as stabilising agents, was characterised. The methodology included indirect tensile stiffness modulus (ITSM) and indirect tensile fatigue tests (ITFT) in strain control mode. The inputs needed for a pavement design analysis with CRBM were then obtained. The results showed the importance of further study on CRBM fatigue to understand the behaviour of these mixes under cyclic loading.

scholarly journals Study of the Stiffness of the Bitumen Emulsion Based Cold Recycling Mixes for Road Base Courses

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5473
Author(s):  
Katarzyna Konieczna ◽  
Piotr Pokorski ◽  
Wojciech Sorociak ◽  
Piotr Radziszewski ◽  
Dawid Żymełka ◽  
...  
Keyword(s):  
Road Construction ◽  
Reclaimed Asphalt Pavement ◽  
Stiffness Modulus ◽  
Pavement Rehabilitation ◽  
Reclaimed Asphalt ◽  
Bitumen Emulsion ◽  
Potential Benefits ◽  
Indirect Tensile ◽  
Reduction Of Energy Consumption ◽  
Cold Recycling

The benefits of the use of cold recycling mixtures (CRMs) in pavement rehabilitation are associated with both the reduction of natural resource consumption by replacing them with recycled materials and the reduction of energy consumption during their production and paving. The evolution of the stiffness of CRMs in road construction and the fatigue life of pavements with CRM base layers are still being investigated. In this paper, CRMs with 1% cement content, called bitumen-stabilized materials with bitumen emulsion (BSM-Es), were examined. Mixtures that were differentiated in terms of Reclaimed Asphalt Pavement (RAP) content, as well as the amount and type of bitumen emulsions, were subjected to indirect tensile stiffness modulus (ITSM) tests at 5 °C, 13 °C, and 20 °C. The thermal sensitivities of the BSM-E mixtures were analyzed. BSM-E mixture stiffness modulus levels at various temperatures were determined using a statistical approach. On the basis of the results obtained, a discussion on the mechanistic-empirical design of flexible pavements with BSM-E base layers is presented. The potential benefits of using BSM-E materials in road construction in certain aspects of pavement life are indicated.

scholarly journals Mechanical performance assessment of half warm recycled asphalt mixes containing up to 100 % RAP

2017 ◽  
Vol 7 (080) ◽  
pp. 129 ◽  
Author(s):  
J. M. Lizárraga ◽  
A. Jiménez del Barco-Carrión ◽  
A. Ramírez ◽  
P. Díaz ◽  
F. Moreno-Navarro ◽  
...  
Keyword(s):  
Hot Mix Asphalt ◽  
Mechanical Performance ◽  
Asphalt Pavement ◽  
Reclaimed Asphalt Pavement ◽  
Recycled Asphalt ◽  
Stiffness Modulus ◽  
Asphalt Mixes ◽  
Reclaimed Asphalt ◽  
Second Stage ◽  
Asphalt Content

The use of Half Warm Mixes with high Reclaimed Asphalt content (HWMRA) has the potential to generate significant environmental advantages such as the reduction in consumption of natural resources and the emission of gases into the atmosphere. This paper therefore focuses on demonstrating the viability of using these types of mixes in wearing courses. For this purpose, an HWMRA with 70 % and 100 % Reclaimed Asphalt Pavement (RAP) and emulsion were designed in the laboratory. The performance of the mixes was then assessed and compared with that of conventional Hot Mix Asphalt. In a second stage, the mixes were manufactured in-plant, and laid and compacted in an Accelerated Pavement Test track. The cores were then extracted and tested for stiffness modulus and resistance to fatigue. The results from the tests conducted with both the laboratory specimens and the cores showed that the performance of HWMRA is comparable to that of HMA. These findings encourage greater confidence in promoting the use of these types of sustainable asphalt mixes.

scholarly journals The water resistance of a recycled base with foamed bitumen in the aspect of road binder composition

2016 ◽  
Vol 15 (1) ◽  
pp. 019-029
Author(s):  
Przemysław Buczyński ◽  
Marek Iwański ◽  
Grzegorz Mazurek
Keyword(s):  
Water Resistance ◽  
Tensile Modulus ◽  
Local Conditions ◽  
Reclaimed Asphalt ◽  
Precise Adjustment ◽  
Mineral Components ◽  
Indirect Tensile ◽  
Binder Composition ◽  
Foamed Bitumen ◽  
Soil Gradation

The paper describes research results of recycled base which was performedin a cold deep recycling technology with foamed bitumen and different type of hydraulicmixed binder in the aspect of water resistance. An individual design of a composition of abinder enables to achieve a precise adjustment of a binder’s impact to local conditions andrequired parameters of a recycled base. The design a recycled base with foamed bitumensimulated a cold deep recycling process with materials from existing crushed bituminouspavement layers ("technology in-situ"). To produce the foamed bitumen a road bitumen ofpenetration grade 50/70 was used. Moreover, the following mineral components werecategorised as a waste material: reclaimed asphalt pavement, 0/31,5 mm aggregate andaggregates for soil gradation improvement 0/4. A composition of the recycled base consisted of the binders prepared in the laboratory as a result of a mix of three basic components.The percentage of individual road binders was determined in line with the plan of thesimlex-centroid experiment. For the purpose of determining an influence of such a hydraulicroad binder on the water resistance in recycled base, the following tests were carried out:void contents Vm, tensile strength ratio TSR (water resistance). Additionally, an evaluationof increase of indirect tensile modulus (IT-CY) was conducted. On the basis of the testresults, a varied impacts of tested hydraulic road binders on mechanical properties andwater resistence of recycled base with foamed bitumen were observed. On the basis of theplan of the experiment, it was possible to determine the recommended road binder composition that enabled to obtain the water resistance in the recycled base with foamed bitumen

scholarly journals Investigation on the Combined Effect of Fibers and Cement on the Mechanical Performance of Foamed Bitumen Mixtures Containing 100% RAP

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ehsan Ashouri Taziani ◽  
Emanuele Toraldo ◽  
Filippo Giustozzi ◽  
Maurizio Crispino
Keyword(s):  
Research Study ◽  
Mechanical Performance ◽  
Asphalt Pavement ◽  
Construction Materials ◽  
Recycled Asphalt ◽  
New Methods ◽  
Dynamic Creep ◽  
Indirect Tensile ◽  
The Common ◽  
Foamed Bitumen

Concerns about virgin aggregate sources and increasing demands for construction materials of transport infrastructures as the key parameters in development are the most important reasons, which convinced pavement engineers to develop new methods in order to use higher amount of recycled asphalt pavement (RAP). One of the common methodologies to produce mixtures containing RAP is foamed bitumen mix (FBM). In addition, according to previous research studies, incorporating various types of fibers and hydraulic binders such as cement could significantly improve the mechanical performance of mixtures. The present research study evaluated FBM containing 100% RAP and two types of fiber and Portland cement. Dynamic modulus, unconfined dynamic creep compression, and indirect tensile strength were evaluated in the laboratory at optimum moisture content, which was investigated in this research. Both types of fiber and cement proved to enhance specific properties of mixtures.

scholarly journals EFFECTS OF GRAPHITE ON MECHANICAL PROPERTIES OF STONE MASTIC ASPHALT PAVEMENT

2017 ◽  
Vol 23 (8) ◽  
pp. 1013-1020 ◽  
Author(s):  
Baha Vural KÖK ◽  
Mehmet YILMAZ ◽  
Yunus ERKUS
Keyword(s):  
Mechanical Properties ◽  
Fatigue Tests ◽  
Modified Bitumen ◽  
Stiffness Modulus ◽  
Bituminous Mixtures ◽  
Mastic Asphalt ◽  
Significant Difference ◽  
Stone Mastic Asphalt ◽  
Indirect Tensile ◽  
Marshall Stability

Hot mix asphalt needs to be developed to resist particular permanent deformations like rutting and thermal cracking due to increased traffic volumes and vehicle loads. Additives such as carbon black, graphite, carbon fibers are used in the mixture or the binder for improving the mechanical features of asphalt. In this article, the effects of graphite used for developing the mechanical properties of asphalt have been investigated in mixtures tests. Therefore, Marshall stability, indirect tensile stiffness modulus and indirect tensile fatigue tests were performed to bituminous mixtures modified with three different proportions of graphite by weight of bitumen. Stone mastic asphalt mixtures which were manufactured with pure and modified bitumen were aged in different time intervals in the oven. In conclusion, it has defined that Marshall stability values have declined. It has been determined that there is no significant difference in the time-dependent deformation behavior of the original and aged samples in pure and different graphite content although the stiffness modulus and load repeat number of the samples increased with the rise of the aging time. These results shown that graphite generally used for improving the thermal properties in literature were also determined to contribute to mechanical properties of mixtures.

Stiffness Evolution of Granular Materials Stabilized with Foamed Bitumen and Cement

2013 ◽  
Vol 2363 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Felipe Halles ◽  
Guillermo Thenoux ◽  
Álvaro González
Keyword(s):  
Stress Level ◽  
Reduction Rate ◽  
Curing Process ◽  
Initial Stiffness ◽  
Stabilizing Agents ◽  
A Value ◽  
Tensile Fatigue ◽  
Analysis Of Results ◽  
Indirect Tensile ◽  
Foamed Bitumen

From the literature, it is possible to find two trends regarding the stiffness evolution of foamed bitumen stabilized–recycled mixtures. The first trend indicates that once the foamed bitumen mix reaches a constant value because of the curing process, the stiffness decreases with time because of load cycles. The second trend indicates that stiffness remains constant after the curing process. In this research, the stiffness evolution of foamed bitumen mixes stabilized with different bitumen and cement contents was studied. The stiffness was measured by using the indirect tensile fatigue test. Results indicated that once the foamed bitumen mix reached a constant value because of the curing process, stiffness decreased or remained constant depending on the stress level applied to the foamed bitumen layer. If the stress level is lower than a specific value, the stiffness of the mix will remain constant at a value extremely close to the initial stiffness. If the stress level is greater than a specific value, the stiffness of the mix will decrease gradually. In addition, the reduction rate of the stiffness will be greater with higher stress level. The analysis of results from mixes with different bitumen and cement contents allows identification of the effect of both stabilizing agents in the long-term stiffness evolution.

scholarly journals Influence of F-T Synthetic Wax on Asphalt Concrete Permanent Deformation

2013 ◽  
Vol 59 (3) ◽  
pp. 295-312
Author(s):  
M. Iwański ◽  
G. Mazurek
Keyword(s):  
Fatigue Life ◽  
Fatigue Test ◽  
Asphalt Concrete ◽  
Permanent Deformation ◽  
Positive Influence ◽  
Test Results ◽  
Fischer Tropsch ◽  
Stiffness Modulus ◽  
Tensile Fatigue ◽  
Indirect Tensile

Abstract The paper presents the results of the study of the effect of a Fischer-Tropsch (F-T) synthetic wax on the resistance to permanent deformation of the AC 11S asphalt concrete. The synthetic wax was dosed at 1.5%, 2.5% and 3.5% by weight of bitumen 35/50. The compaction temperatures were 115°C, 130°C and 145°C. The criteria adopted for measuring the resistance to permanent deformation included the following parameters: stiffness modulus at 2, 10 and 20°C, permanent deformation (RTS), fatigue life determined using the indirect tensile fatigue test (ITFT) and resistance to rutting (WTSAIR, PRDAIR). The test results confirmed the positive influence of F-T synthetic wax on enhancing the permanent deformation resistance of asphalt concrete placed at lower compaction temperatures compared to that of standard asphalt concrete compacted at 140°C.

Experiment Study on Temperature Susceptibility of Cold Recycled Mix with Foamed Bitumen

2011 ◽  
Vol 374-377 ◽  
pp. 1627-1631
Author(s):  
Jin Zhi Xu ◽  
Pei Wen Hao
Keyword(s):  
Mechanical Properties ◽  
Asphalt Pavement ◽  
Compression Modulus ◽  
Recycled Asphalt ◽  
Tensile Strength Test ◽  
Bitumen Content ◽  
Indirect Tensile ◽  
Foamed Bitumen ◽  
Strength And Stiffness ◽  
Temperature Susceptibility

By using indirect tensile strength test and compression modulus test, the influences of variables, including recycled asphalt pavement (RAP) content and foamed bitumen content, on temperature susceptibility of mechanical properties of cold recycled mix with foamed bitumen (CRMFB) were studied. The results indicated that increase of RAP content had little impact on temperature susceptibility of CRMFB when small quantity of RAP (less than 70%) were contained, while enhanced temperature susceptibility of CRMFB was brought about when a large quantity of RAP (more than 70%) were contained. The mechanical properties, including strength and stiffness, manifested enhanced temperature susceptibility with the increase of foamed bitumen contents. Compared with HMA, CRMFB was obviously less susceptive to temperature.

Sign in / Sign up

Export Citation Format

Share Document