Generating 2D Three-phase Asphalt Mixture Representation Using advanced Digital Image Processing (DIP) techniques

Augusto Cannone Falchetto,KiHoon Moon 한국도로학회 2015 한국도로학회 학술발표회 논문집 Vol.2015 No.10

Analyzing asphalt mixture images can provide crucial information not only for generating advanced geometry structure in several numerical computations (i.e. FEM and/or DEM) codes, but also for numerically evaluating the material microstructure. It is well known that 3D X-Ray Computer Tomography (CT) can provide accurate and realistic microstructure information of asphalt mixtures; however, this technology still presents two limitations: 1) the equipment is very expensive and, therefore, only few pavement agencies can afford it, and 2) the software required to generate realistic image of asphalt mixture with three-phase structure (aggregate, asphalt binder and air-voids) is based on a global thresholding algorithm which cannot be easily accessed and edited by users and practitioners. In this paper, accurate and realistic 2D three-phase asphalt mixture images were generated using an advanced DIP analysis code (implemented on MATLABTM) and a common flatbed scanner, which can be easily purchased at relatively low price. The threshold algorithm was developed based on the computed results of Gmm (maximum specific gravity), Gmb (bulk specific gravity), VMA (voids in mineral aggregates) of given asphalt mixtures which can be experimentally obtained in a laboratory environment. 2D three-phase images of asphalt mixtures were derived from grey scale images (color intensity from 0 to 255) obtained from original RGB (Red-Green-Blue) scale images with a dual-threshold computation techniques (i.e. one step for computing air voids phase, T1, and a second step for computing asphalt binder (and/or mastic) phase, T2). An example of DIP analysis results is shown in Figure 1. Based on the computation results, quite accurate and good visual agreement was observed between RGB scale image and DIP analyzed image. The findings indicate that this advanced DIP analysis technique can provide reliable geometry and microstructural information for several numerical simulations such as finite element method (FEM) and discrete element modeling (DEM). This research work represents a solid base for performing simple 2D microstructure analysis using 2- and 3-point correlation function and for developing the Moon Cannone Falchetto (MCF) model which will be introduced in the next annual KSRE conference.

Mechanical performance evaluation of taconite aggregate in asphalt pavement construction

Augusto Cannone Falchetto,문기훈,조상갑 한국아스팔트학회 2022 한국아스팔트학회지 Vol.12 No.1

Using alternative aggregate source is essential in asphalt pavement industry not only for saving construction budget but also for mitigating environmental pollution issue. In U.S. northern Minnesota territory, amount of taconite aggregate: a byproduct of taconite mining industries, are produced annually. If taconite aggregate is successfully used as an alternative aggregate source, more economical and environment friendly asphalt mixture can be achieved. Many studies presented the possibility of taconite aggregate application in road construction. In this paper, suitability investigation of using taconite aggregate is performed by means of mechanical test: low temperature Indirect Tensile (IDT) creep test. A parameter for low temperature cracking resistance: creep stiffness (and corresponding relaxation modulus) result, is computed then compared visually. It was found that the asphalt mixture mixed with coarse taconite aggregate and limestone filler presented reasonable mechanical performance compared to the conventional asphalt mixture. This finding provides possibility of taconite aggregate application in actual asphalt pavement construction.

Feasibility analysis of taconite aggregate application by means of composite pavement structure design simulation using MEPDG

Augusto Cannone Falchetto,문기훈,조상갑 한국아스팔트학회 2022 한국아스팔트학회지 Vol.12 No.1

It is well known that application of alternative aggregate material in asphalt pavement area is crucial not for saving construction budget but for mitigating environmental pollution. Several research efforts: for finding alternative aggregate material, were performed in U.S. during the past decades. One of the research achievements is application of taconite aggregate: a byproduct of taconite mining industries in northern Minnesota, U.S., in asphalt pavement construction. Some studies performed performance evaluation of taconite aggregate added mixture with various mechanical testing procedure. However, not many studies considered pavement design performance simulation, evaluation and comparison in case of taconite aggregate application. In this paper, performance evaluation of taconite aggregate mixture by means of composite pavement design simulation using AASHTOWare-Pavement (MEPDG: Mechanical-Empirical Pavement Design Guide) was considered. Reasonable and comparable pavement performance was found when taconite aggregate is applied compared to the conventional asphalt mixture.

Reuse of Electric Arc Furnace Steel Slags in Asphalt Pavement Mixtures

Augusto Cannone Falchetto,Ki Hoon Moon 한국도로학회 2014 한국도로학회 학술발표회 논문집 Vol.2014 No.9

The potential of marginal materials as components of road infrastructures has been studied for many years. The list of materials includes non-traditional natural materials (rocks and soils), industrial by-products (from metallurgical industry, thermal electric power stations, and chemical industry) and wastes (mining and quarrying, municipal, industrial and demolition wastes). Among these materials, Electric Arc Furnace Steel Slags (EAFSS) presents physical-mechanical characteristics and full chemical compatibility with the hydrocarbon binders used in road construction and, therefore, have high potential for being re-used. This paper presents the results of a laboratory study conducted to verify the suitability of a particular type of Electric Arc Furnace Steel Slag (EAFSS) to be recycled in the aggregate skeleton of dense graded and porous asphalt mixtures for pavements application. One dense graded mixture for wearin gcourse(WCAC), one Stone Mastic Asphalt(SMA) and one Porous Asphalt(PA) were prepared and compacted for this purpose. The computed results of Marshall Stability, Flow and Indirect Tensile Strength (ITS) values are presented in Table 1.

Remarks on the use of Electric Arc Furnace (EAF) Steel Slag in Asphalt Mixtures for Flexible Pavements

Augusto Cannone Falchetto,문기훈 한국도로학회 2015 한국도로학회논문집 Vol.17 No.1

PURPOSES: This paper, presents the results of a laboratory study aimed to verify the suitability of a particular type of Electric Arc Furnace (EAF) steel slag to be recycled in the lithic skeleton of both dense graded and porous asphalt mixtures for flexible pavements. METHODS : Cyclic creep and stiffness modulus tests were performed to evaluate the mechanical performance of three different asphalt mixtures (dense graded, porous asphalt, and stone mastic) prepared with two types of EAF steel slag. For comparison purposes, the same three mixtures were also designed with conventional aggregates (basalt and limestone). RESULTS : All the asphalt mixtures prepared with EAF steel slag satisfied the current requirements of the European standards, which support EAF steel slag as a suitable material for flexible pavement construction. CONCLUSIONS : Based on the experimental work, the use of waste material obtained from steel production (e.g. EAF steel slag) as an alternative in the lithic skeleton of asphalt mixtures can be a satisfactory and reasonable choice that fulfills the “Zero Waste”objective that many iron and steel industries have pursued in the past decades.

MN/Road 시험포장 구간내의 공기량 측정 및 결과값 분석을 통한 RAP 및 저온 아스팔트(WMA) 혼합물의 특성 평가

Ki Hoon Moon,Augusto Cannone Falchetto,Jin Hoon Jeong 한국도로학회 2014 한국도로학회논문집 Vol.16 No.4

PURPOSES: This research is to evaluate the mechanical performance of different types of Hot Mix Asphalt (HMA) pavement cells prepared for MN/Road field testing section through an extensive experimental analysis of air voids and simple statistical evaluation tools (i.e. hypothesis test). METHODS: An extensive experimental work was performed to measure air voids in 82 asphalt mixture cores (238 samples in total) obtained from nine different types of road cell located in MN/Road testing field. In order to numerically and quantitatively address the differences in air voids among the different test Cells built in MN/Road, a simple statistical test method (i.e. t-test) with 5% significance was used. RESULTS: Similar trends in air voids content were found among the mixtures including conventional HMA, Reclaimed Asphalt Pavement (RAP) and Warm Mix Asphalt (WMA) combined with taconite aggregate this provides support to the use of RAP and WMA technology in the constructions of asphalt pavement. However, in case of acid modified HMA mixtures, significant differences in air void content were observed between on the wheel path and between wheel path location, which implies negative performances in rutting and thermal cracking resistances. Conclusions : It can be concluded that use of RAP and WMA technology in the construction of conventional asphalt pavement and the use of PPA (Poly Phosphoric Acid) in combinations with SBS (Styrene Butadiene Styrene) in asphalt binder production provide satisfactory performance and, therefore, are highly recommended

최적화된 시멘트 아스팔트 모르타르(CAM) 설계를 위한 다양한 유화제가 적용된 아스팔트 바인더의 유변학적 평가

조상갑,문기훈,Augusto Cannone Falchetto,강일환,박태순 한국아스팔트학회 2023 한국아스팔트학회지 Vol.13 No.1

Designing an optimized Cement Asphalt Mortar (CAM) is essential not only for providing smoother riding quality on road pavements but also for reducing vibration and noise on railways. In producing CAM material, one of the most crucial factors is the selection of asphalt binders with good mixing compatibility when combined with various emulsifying agents. Many emulsifying agents and corresponding modified asphalt binders have been studied and developed over the past decades to improve the material performance of the asphalt mixture. However, the mechanical properties of blends of asphalt binder and emulsifying agents were not studied and considered significantly from a perspective of an application in railways. This demands a dedicated evaluation of these asphalt binder blends using various mathematical models in the attempt to design better-performing CAM. In this paper, a rheological evaluation of asphalt binder mixed with three emulsifying agents was performed with different mathematical models, including a newly developed formulation named C2MKP model. Dynamic Shear Rheometer (DSR) tests were conducted as experimental work. Complex modulus and phase angle results were computed; then, the corresponding master curve was generated based on different mathematical models. All the results were compared visually on a wide range of given test frequencies. It was found that modified asphalt binder can provide similar rheological performance compared to the conventional asphalt binder, suggesting that modified asphalt binder can be successfully adopted in the CAM production for railways.

An Alternative One-Step Computation Approach for Computing Thermal Stress of Asphalt Mixture: the Laplace Transformation

문기훈,권오선,조문진,Cannone Falchetto Augusto 대한토목학회 2019 대한토목학회논문집 Vol.39 No.1

Computing low temperature performance of asphalt mixture is one of the important tasks especially for cold regions. It is well known that experimental creep testing work is needed for computation of thermal stress and critical cracking temperature of given asphalt mixture. Thermal stress is conventionally computed through two steps of computation. First, the relaxation modulus is generated thorough the inter-conversion of the experimental creep stiffness data through the application of Hopkins and Hamming’s algorithm. Secondly, thermal stress is numerically estimated solving the convolution integral. In this paper, one-step thermal stress computationmethodology based on the Laplace transformation is introduced. After the extensive experimental works and comparisons of twodifferent computation approaches, it is found that Laplace transformation application provides reliable computation results comparedto the conventional approach: using two step computation with Hopkins and Hamming’s algorithm.

Testing and Modelling of Hygro-thermal Expansion Properties of Concrete

임진선,문기훈,Augusto Cannone Falchetto,정진훈 대한토목학회 2016 KSCE Journal of Civil Engineering Vol.20 No.2

This paper investigates the hygro-thermal expansion behavior of concrete as a function of the internal temperature and humidity changes caused by thermodynamics and moisture diffusion. The effects of age and moisture on the Coefficient of Thermal Expansion (CTE) of concrete were evaluated by measuring the temperature, humidity, and strain of cylindrical and prismatic concrete specimens. Based on the measurements, the effects of age and moisture on the concrete CTE were analyzed. In addition, CTE, which depends on moisture, was modeled and validated by comparison with existing research results. The study results indicate that the effect of age on concrete CTE is not significant. CTE was maximized at a concrete humidity of 85% and was about 1.6 times larger than the minimum CTE measured at a humidity of 95~100% or below 50%. The hygro-thermal model developed in this study predicted the measured CTE reasonably well. The CTE of a concrete slab is an important parameter in the design of concrete pavement. More accurate design methodology can be implemented by including the effect of moisture on CTE.

Rheological Evaluation of Emulsifying Agent-Added Asphalt Binder for Cement Asphalt Mortar (CAM) Design by Means of Optimized Master Curve Modeling Approach

조상갑,문기훈,Augusto Cannone Falchetto,강일환,박태순 한국철도학회 2023 한국철도학회논문집 Vol.26 No.2

Designing an optimized Cement Asphalt Mortar (CAM) is essential not only for providing smoother riding quality on road pavements but also for reducing vibration and noise on railways. In producing CAM material, a crucial factor is the selection of asphalt binders with good mixing compatibility when combined with various emulsifying agents. Many emulsifying agents and corresponding modified asphalt binders have been studied and developed over the past decades to improve the material performance of the asphalt mixture. However, mechanical properties of blends of asphalt binder and emulsifying agents have not been studied or considered significantly from a perspective of application to railways. This demands a dedicated evaluation of these asphalt binder blends using various mathematical models in an attempt to design a better-performing CAM. In this paper, a rheological evaluation of asphalt binder mixed with three emulsifying agents was performed with different mathematical models, including a newly developed formulation called the C2MKP model. Dynamic Shear Rheometer (DSR) tests were conducted as experimental work. Complex modulus and phase angle results were computed; then, a corresponding master curve was generated based on different mathematical models. All the results were compared visually on a wide range of given test frequencies. It was found that modified asphalt binder can provide rheological performance similar to that of conventional asphalt binder, suggesting that modified asphalt binder can be successfully adopted in CAM production for railways.