Experimental investigation and multi-objective optimization of fracture properties of asphalt mixtures containing nano-calcium carbonate
Introduction
Nowadays, with the increase in maintenance costs as well as increased traffic loads on asphalt pavements, the attention of researchers is changed on reducing breakdowns, including rutting, fatigue cracks, low-temperature cracks and so on. The above-mentioned breakdowns reduce the safety and service level of roads during the lifetime of pavement operation and impose a lot of costs on governments [1], [2], [3], [4]. So many studies have been conducted to reduce or retard the aforementioned distresses. One of the most degradation and failure modes in the asphalt pavement, especially in cold areas, is low-temperature cracks, in which high amounts of costs are paid for repairing the road pavements annually. Two principal parameters in the start and propagation of crackings are traffic loadings and thermal stresses in asphalt pavements [5]. Temperature variations can cause tensile thermal stresses in asphalt pavements, thus the asphalt may be put in mode I deformation (crack opening). Nevertheless, traffic loads may cause various deformation combinations of tension (mode-I) and shear (mode-II) based on the vehicle wheels’ location related to the cracks [6].
As asphalt pavements must today have the durability and stability needed to withstand the stresses of traffic loads and heat stresses, various additives have been used to enhance the mechanical characteristics of asphalt mixtures. Recently, the utilization of different nano-materials, including nano-titanium, nano-silicon dioxide [7], nano-clay [8], nano-zinc oxide [9], carbon nano-fiber [10] and so on has been extensively increased. The properties of additives added to bitumen must be such that they can be compatible with the chemical composition of bitumen and asphalt. This adaptation depends on the composition of base asphalts, polarity, particle size, the molecular structure of additives, interfacial interactions between asphalt-additive and so on. The type of additive, preparation temperature and modification steps are also effective in improving asphalt performance [11], [12], [13].
Many studies have been conducted on the fracture behavior of asphalt samples. Behbahani et al. (2013) explored the impact of various additives, including polyphosphoric acid, anti-stripping agent, styrene-butadienestyrene, sasobite and crumb rubber on the mode-I fracture of asphalt samples. They illustrated that these additives increased the fracture toughness of mixtures at a low temperature and using sasobite and crumb rubber resulted in the maximum increment of the fracture toughness value in pure mode-I (KIf) amounts [14]. Aliha et al. (2014) examined the impact of asphalt properties on the fracture behavior of asphalt samples in mixed-mode I/II using asymmetric semi-circular bending (SCB) samples. They illustrated that mixtures constructed with bitumen PG 64-22 had higher peak loadings compared to bitumen PG 52-28 and so, greater fracture toughness was achieved at the start of first fracture increase. Also, the effective fracture toughness amounts in the mixed-mode (Keff) were less than the fracture toughness amounts in pure mode-I or pure mode-II (KIf and KIIf) [15]. Ameri et al. (2016) explored the impact of carbon nanotubes (CNT) at five different contents of 0.2% to 1.5% on the fracture energy of asphalt mixtures by the use of SCB samples. Results indicated that CNT enhanced the fracture resistances of mixtures, especially at greater CNT contents [16]. Mansourian et al. (2016) studied the impact of sasobite and jute fiber in four different percentages on the low temperature fracture behavior of asphalt samples at −20, −10 and 0°. The finite element method was performed to achieve the geometry parameters of SCB samples in pure mode I, pure mode II and mixed-mode I/II loadings. The fracture resistance was then calculated. They illustrated that jute fiber enhanced the fracture resistance in pure mode I and mixed-mode with a greater tension proportion and the optimal percentage of jute fibers was approximately 0.3% [17]. Fakhri et al. (2018) examined the fracture energy of asphalt mixtures in mixed-mode I/II by the use of SCB samples at a moderate temperature. The impact of bitumen and aggregate types and air voids on the fracture behavior was explored. They indicated that these factors could significantly influence on the fracture resistance of mixtures at the intermediate temperature [18]. Ziari et al. (2019) examined the impact of three rejuvenators, such as Cyclogen, Rapiol, and waste cooking oil (WCO), on the asphalt fracture behavior at 25 °C. Also, they explored the impact of short and long-term aged samples on the fracture behavior of recycled asphalt mixtures. They showed that aging had a negative impact on asphalt fracture resistance and asphalt samples containing WCO had the greatest reduction in fracture energy after aging [19]. Pirmohammad et al. (2019) explored the impact of CNT and nano Fe2O3 at four various contents on fracture characteristics of asphalt mixtures by the use of SCB samples subjected to mixed-mode I and II loadings. They illustrated that both additives remarkably enhanced the fracture characteristics of mixtures. However, the fracture resistance of asphalt samples was more enhanced by CNT than nano Fe2O3. Also, samples in mode-I loading had the greatest enhancement in the fracture resistance. Results also indicated that the appropriate percentage of CNT for modifying asphalt mixtures was 1.2%. [20]. Pirmohammad et al. (2020) explored the carbon and kenaf fibers on the fracture resistance of asphalt samples under modes I and II and mixed mode through SCB test at a low temperature (-15 °C). Results indicated that both the additives enhanced the fracture toughness of mixtures. Using carbon fiber (as a superior material) up to 42% increased the fracture toughness in mode-I. Also, increasing the shear mode’s proportion at the crack front of mixtures resulted in a reduction of the positive impact of the additives [21].
For determination of the optimum amounts, one may create a mathematical relationship firstly which can be obtained by system identification models such as regression, neural network and evolutionary algorithms [22]. In multi-objective optimization (MO) problems, there is a set of optimal solutions, called Pareto fronts [23]. For solving these problems, the genetic algorithm can be used as an evolutionary algorithm. The non-dominated sorting genetic algorithm II (NSGA-II) method which was formed according to a genetic algorithm can properly deal with MO problems [24].
Various researches have been performed by the use of the NSGA-II method in pavements that were often in pavement management field [25], [26], [27], [28], [29], as well as other fields in pavements [30], [31], [32], [33]. But limited studies have been performed to explore the exact optimum amount of an additive (i.e., NCC) with two objectives of and simultaneously. In this study, a precise amount of NCC was obtained to improve the fracture behavior of asphalt samples. On the other, various researches have been done on the utilization of nano-materials in asphalts. But limited researches have been performed on the examination of fracture toughness of asphalt mixtures containing nano-calcium carbonate (NCC). So in this research, the effect of NCC as a bitumen modifier with weight percentages of 1%, 3%, 5% and 7% was investigated on low-temperature asphalt fracture behavior in mode-I, mode-II and mixed-mode I/II using SCB samples made with two bitumen types of PG 64-22 and PG 58-28 and linear elastic fracture mechanic (LEFM) method. Also, statistical analysis and prediction models of and were performed using multivariate regression (MVR) analysis and two neural network methods of group method of data handling (GMDH) and genetic programming (GP) in order to determine the best method with greater accuracy and lower error, and then by the use of the best method relation, NCC additive content was optimized to maximize and values simultaneously.
Section snippets
Fracture tests and finite element (FE) analysis
Various types of tests used to determine the fracture resistance of asphalt samples can be SCB [17], [18], [20], [21], [34], disk-shaped compact tension (DC (T)) [35], [36], [37], [38], [39], edge-notched disc bend (ENDB) [40], [41], [42], indirect tension test (IDT) [43], [44], [45], [46] and TTI upgraded overlay tester [47], [48], [49], [50], [51]. Nevertheless, some of the aforementioned tests have their own weaknesses and faults. However, the SCB sample looks to be a good candidate sample in
Aggregate
The applied aggregate in this research was limestone. The aggregate gradation was based on ASTM standard that the nominal and maximum sizes of aggregate are 1.25 cm and 1.9 cm, respectively. The aggregate gradation is represented in Fig. 3. Moreover, the physical properties of aggregate are illustrated in Table 1.
Bitumen
In this paper, two bitumen types, PG (64-22) with 60/70 penetration grade and PG (58-28) with 85/100 penetration grade, were used as base bitumens, the characteristics of which are
Modeling methods
MVR, GMDH and GP models were used in this study to present the fracture toughness models in modes I and II, and finally, the optimum additive content was represented in the optimization procedure. MVR was used for investigating the relation of independent and dependent parameters and comparing new models with classical ones and for further exact predictions, GMDH and a type of genetic algorithm called GP were applied.
Results and discussions
The results of fracture toughness tests performed in pure modes I and II and two mixed modes loadings on SCB samples containing 1%, 3%, 5% and 7% NCC as well as unmodified mixtures considering two bitumen types of PG 64-22 and PG 58-28 at −10 °C are presented in this section. Moreover, statistical analysis and prediction methods of and were performed using MVR analysis and two neural network models of GMDH and GP for determining the best model with greater accuracy and lower error, and
Conclusion
In this research, the effect of NCC as a bitumen modifier with weight percentages of 1%, 3%, 5% and 7% was investigated on low-temperature asphalt fracture behavior in pure mode-I, pure mode-II and two mixed-modes I/II using SCB samples constructed with two bitumen types (PG 64-22 and PG 58-28) and then by selecting the best model relationship for two-objective optimization of and , the optimal NCC content was determined. The main findings of the research are:
- -
The fracture toughness of
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
CRediT authorship contribution statement
Ahmad Ghasemzadeh Mahani: Data curation, Investigation. Payam Bazoobandi: Data curation, Writing - original draft. Seyed Mohsen Hosseinian: Methodology, Writing - review & editing. Hassan Ziari: Methodology.
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References (79)
Temporal-spatial evolution characteristics of acoustic emission in asphalt concrete cracking process under low temperature
Constr. Build. Mater.
(2020)- et al.
Effect of wetting–drying cycles on mode I and mode II fracture toughness of sandstone in natural (pH = 7) and acidic (pH = 3) environments
Theor. Appl. Fract. Mech.
(2020) - et al.
Effects of nanoclay on rheological properties of bitumen binder
Constr. Build. Mater.
(2009) - et al.
The impact of carbon nano-fiber modification on asphalt binder rheology
Constr. Build. Mater.
(2012) Chemical composition of asphalt as related to asphalt durability
- et al.
Effect of chemical composition on rheology and mechanical properties of asphalt binder
Constr. Build. Mater.
(2014) - et al.
Thermal analysis on the component interaction of asphalt binders modified with crumb rubber and warm mix additives
Constr. Build. Mater.
(2016) Study of characteristic specification on mixed mode fracture toughness of asphalt mixtures
Constr. Build. Mater.
(2014)- et al.
Evaluation of fracture resistance of warm mix asphalt containing jute fibers
Constr. Build. Mater.
(2016) - et al.
Mixed mode tensile – in plane shear fracture energy determination for hot mix asphalt mixtures under intermediate temperature conditions
Eng. Fract. Mech.
(2018)
The effect of rejuvenators on the aging resistance of recycled asphalt mixtures
Constr. Build. Mater.
Laboratory investigations on fracture toughness of asphalt concretes reinforced with carbon and kenaf fibers
Eng. Fract. Mech.
LID-BMPs planning for urban runoff control and the case study in China
J. Environ. Manage.
Robust design approach for flexible pavements to minimize the influence of material property uncertainty
Constr. Build. Mater.
Effect of specimen thickness on the fracture resistance of hot mix asphalt in the disk-shaped compact tension (DCT) configuration
Constr. Build. Mater.
Self-healing of thermal cracks in asphalt pavements
Constr. Build. Mater.
Fracture properties of asphalt concrete under various displacement conditions and temperatures
Constr. Build. Mater.
An extended edge-notched disc bend (ENDB) specimen for mixed-mode I+II fracture assessments
Int. J. Solids Struct.
Evaluation of temperature and loading rate effect on fracture toughness of fiber reinforced asphalt mixture using edge notched disc bend (ENDB) specimen
Constr. Build. Mater.
Evaluating mode I fracture resistance in asphalt mixtures using edge notched disc bend ENDB specimen with different geometrical and environmental conditions
Eng. Fract. Mech.
Mixed mode fracture resistance of asphalt concrete mixtures
Eng. Fract. Mech.
Cracked asphalt pavement under traffic loading – a 3D finite element analysis
Eng. Fract. Mech.
Mixed-mode stress intensity factor solutions of a warped surface flaw by three-dimensional finite element analysis
Eng. Fract. Mech.
Three-dimensional mixed-mode fatigue crack growth in a functionally graded titanium alloy
Eng. Fract. Mech.
New model of moisture susceptibility of nano silica-modified asphalt concrete using GMDH algorithm
Constr. Build. Mater.
Formulation of flow number of asphalt mixes using a hybrid computational method
Constr. Build. Mater.
Improving the moisture performance of hot mix glass asphalt by high-density polyethylene as an asphalt binder modifier
Int. J. Sustainable Build. Technol. Urban Develop.
Prediction and pareto-based multi-objective optimization of moisture and fatigue damages of asphalt mixtures modified with nano hydrated lime
Constr. Build. Mater.
Investigation of moisture sensitivity and conductivity properties of inductive asphalt mixtures containing steel wool fiber
Adv. Civil Eng.
Presentation of a new deicer with the least moisture and fatigue failures in asphalt mixtures
Arabian J. Sci. Eng.
Study on road performance of nano-SiO2 and nano-TiO2 modified asphalt
New Build. Mater.
Experimental fracture toughness study for some modified asphalt mixtures
Advanced Materials Research
Investigation of fatigue and fracture properties of asphalt mixtures modified with carbon nanotubes
Fatigue Fract. Eng. Mater. Struct.
Experimental investigation of fracture properties of asphalt mixtures modified with Nano Fe2O3 and carbon nanotubes
Road Mater. Pavem. Des.
CFD simulation and Pareto-based multi-objective shape optimization of the centrifugal pump inducer applying GMDH neural network, modified NSGA-II, and TOPSIS
Struct. Multidiscip. Optim.
A comprehensive survey of evolutionary-based multiobjective optimization techniques
Knowl. Inf. Syst.
A fast and elitist multiobjective genetic algorithm: NSGA-II
IEEE Trans. Evol. Comput.
Multiobjective optimization in pavement management system using NSGA-II method
J. Transp. Eng., Part B: Pavements
Cited by (28)
Research on the influence of parameters on the fracture performance of the large stone asphalt mixture based on the semi-circular bending test
2024, Construction and Building MaterialsImproving flame retardancy, fume suppression and mechanical properties of SBS modified binder using nano-porous fibers prepared by electrospinning
2023, Construction and Building MaterialsA review on evaluation of crack resistance of asphalt mixture by semi-circular bending test
2023, Journal of Road Engineering