Научная статья на тему 'METHOD OF FORECASTING THE STRENGTH AND THERMAL SENSITIVE ASPHALT CONCRETE'

METHOD OF FORECASTING THE STRENGTH AND THERMAL SENSITIVE ASPHALT CONCRETE Текст научной статьи по специальности «Строительство и архитектура»

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Magazine of Civil Engineering
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Ключевые слова
PAVEMENT / ASPHALT CONCRET / BITUMEN / INTERPHASE LAYER / RHEOLOGY / EXTENSIVE AND INTENSIVE FACTORS / STRENGTH / THERMAL SENSITIVE

Аннотация научной статьи по строительству и архитектуре, автор научной работы — Shekhovtsova S.Yu., Korolev E.V., Inozemtcev S.S., Yu J., Yu H.

A distinctive feature of composites is the manifestation of a synergistic effect due to the interaction of contacting substances at the interphase layer, and their intensity of interaction affects the volume properties of the composites. A study of the interphase layer of bitumen was carried out on the surface of the mineral powder. The proposed method according to the results of rheological tests allows calculating the thickness of the boundary layer in the binary system “asphalt - dispersed phase”. The dependence of the road composite strength on the layer thickness of structured asphalt is established: the strength of the composite increases with increasing thickness of the bitumen layer. Method of assessing the impact on the structural-sensitive properties of the composite extensive factor m - indicator reflecting the influence of the interface area and intensive factor n - indicator reflecting the influence of physicochemical effects at the interface is proposed. The extensive factor has a greater effect on the properties of SMA-20 with a quartz filler m/n > 2. There is a higher rate of decrease in the intensity of physicochemical interactions at the interface of the “oil bitumen-silica filler” phase as compared with the extensive factor. The different nature of the effect of temperature on the extensive and intensive factors is observed for SMA-20 with diatomite: as temperature increases, the factor m increases, whereas the opposite effect is observed for factor n. It indicates a positive effect of the specific surface of diatomite on the temperature properties of asphalt concrete.

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МЕТОДИКА ПРОГНОЗИРОВАНИЯ ПРОЧНОСТИ И ТЕРМОЧУВСТВИТЕЛЬНОСТИ АСФАЛЬТОБЕТОНА

Отличительной особенностью композитов является проявление синергетического эффекта вследствие взаимодействия контактирующих веществ на границе раздела фаз, а их интенсивность взаимодействия влияет на объемные свойства композитов. В работе произведено исследование межфазного слоя битума на поверхности минерального порошка. Предложена методика позволяющая, по результатам реологических испытаний, рассчитать толщину граничного слоя в бинарной системе «нефтяной битум - дисперсная фаза». Установлена взаимосвязь, описывающая зависимость толщины слоя структурированного нефтяного битума с прочностью дорожного композита: увеличение толщины слоя битума на поверхности минерального порошка приводит к увеличению прочности композита. Предложена методика для количественной оценки влияния на структурно-чувствительные свойства композита экстенсивного фактора m - показателя, характеризующего влияние площади границы раздела фаз и интенсивного фактора n - показателя, характеризующего влияние физико-химического воздействия на границе раздела фаз. Установлено, что для щебеночно-мастичного асфальтобетона ЩМА-20, изготовленного с применением кварцевого наполнителя более существенное влияние оказывает экстенсивный фактор m/n>2. Также для него характерна более высокая скорость снижения интенсивности физико-химических взаимодействий на границе раздела фаз «нефтяной битум-кварцевый наполнитель» по сравнению с экстенсивным фактором. Для ЩМА-20, приготовленного с применением диатомита, установлено отличное от симбатного снижения факторов n и m с ростом температуры, установлен различный характер влияния температуры на экстенсивный и интенсивный факторы: при ее увеличении фактор m увеличивается, тогда, как для фактора n наблюдается противоположное влияние. Это свидетельствует о положительном влиянии удельной поверхности диатомита на температурные свойства асфальтобетона.

Текст научной работы на тему «METHOD OF FORECASTING THE STRENGTH AND THERMAL SENSITIVE ASPHALT CONCRETE»

Magazine of Civil Engineering. 2019. 89(5). Pp. 129-140 Инженерно-строительный журнал. 2019. № 5(89). С. 129-140

Magazine of Civil Engineering

journal homepage: http://engstroy.spbstu.ru/

ISSN

2071-0305

DOI: 10.18720/MCE.89.11

Method of forecasting the strength and thermal sensitive asphalt concrete

S.Yu. Shekhovtsovaa*, E.V. Koroleva, S.S. Inozemtcev, J. Yub, H. Yub

a National Research Moscow State Civil Engineering University, Moscow, Russia b South China University of Technology, Guangzhou, China * E-mail: SHehovtsovaSYU@mgsu.ru

Keywords: pavement, asphalt concret, bitumen, interphase layer, rheology, extensive and intensive factors, strength, thermal sensitive

Abstract. A distinctive feature of composites is the manifestation of a synergistic effect due to the interaction of contacting substances at the interphase layer, and their intensity of interaction affects the volume properties of the composites. A study of the interphase layer of bitumen was carried out on the surface of the mineral powder. The proposed method according to the results of rheological tests allows calculating the thickness of the boundary layer in the binary system "asphalt - dispersed phase". The dependence of the road composite strength on the layer thickness of structured asphalt is established: the strength of the composite increases with increasing thickness of the bitumen layer. Method of assessing the impact on the structural-sensitive properties of the composite extensive factor m - indicator reflecting the influence of the interface area and intensive factor n - indicator reflecting the influence of physicochemical effects at the interface is proposed. The extensive factor has a greater effect on the properties of SMA-20 with a quartz filler m/n > 2. There is a higher rate of decrease in the intensity of physicochemical interactions at the interface of the «oil bitumen-silica filler» phase as compared with the extensive factor. The different nature of the effect of temperature on the extensive and intensive factors is observed for SMA-20 with diatomite: as temperature increases, the factor m increases, whereas the opposite effect is observed for factor n. It indicates a positive effect of the specific surface of diatomite on the temperature properties of asphalt concrete.

The purpose of actual research in the field of road construction is to establishing the processes of structure formation of materials at the micro level and the nanolevel. Bitumen is a microheterogeneous system consisting of complex structural units (size from 20 to 60 nm), which form a special structure with the addition of filler in the asphalt concrete composition [1]. Bituminous components adsorbed on the surface of the aggregate form bituminous films, which leads to the strong bonds formation in the structure of asphalt concrete. Basically oriented layers of bitumen are formed due to physical sorption.

General provisions on the relationship of the filler particle size and the dispersed bitumen system are considered in the work [2]. However, to determine the thickness of the films that form on the surface of the filler is not possible. It is known that the bitumen viscosity in the solvation shell (which is called «structured bitumen») is several orders of magnitude higher than the bulk bitumen viscosity. One of the first methods for determination of solvation shell thickness was proposed in [3]. The method is based on the classical model [4] for the viscosity of medium with non-interacting solid spherical particles. While such a model is only appropriate for diluted systems [5]. Methods of calculating the bitumen film thickness in asphalt concrete are proposed [69]. But the proposed methods allow to calculating of the relative values of bitumen film the thickness and do

Shekhovtsova, S.Yu., Korolev, E.V., Inozemtcev, S.S., Yu, J., Yu, H. Method of forecasting the strength and thermal sensitive asphalt concrete. Magazine of Civil Engineering. 2019. 89(5). Pp. 129-140. DOI: 10.18720/MCE.89.11

Шеховцова С.Ю., Королев Е.В., Иноземцев С.С., Ю Д., Ю Х. Методика прогнозирования прочности и термочувствительности асфальтобетона // Инженерно-строительный журнал. 2019. № 5(89). С. 129-140. DOI: 10.18720/MCE.89.11

1. Introduction

(°0

This open access article is licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

not allow to calculating of the quantitative value of the adsorbed bitumen, on the value of which the asphalt concrete strength depends.

A feature of composites is the manifestation of a synergistic effect due to the interaction of contacting substances at the interface [10]. Often this interaction results in the formation of a layer with altered properties. It has been shown in the A.I. Rusanovs works [11, 12] that the investigated property of the dispersion medium varies with the layer thickness h according to the law:

SF = A, h3

where A is a constant, which, depending on the intensity of the interaction at the interface, can be not only positive values, but also of negative ones; the "5" sign means a relative change in property.

In [13], it was shown that the interaction intensity at the border of chapter can also affect the bulk properties of composites, and in [14] a method is proposed for estimating the level of layer strength change based on concentration dependencies of the composite strength. The importance this layer for the composite properties was emphasized by some researchers by the introduction of a separate name — "film phase" [15-17]. As a rule, an increase in the content of the film phase results in an increase in the indicators of the composite structural-sensitive properties [19-21]. Matrix material lack, which is accompanied by an increase in porosity and the formation of aggregates — particles of the dispersed phase not wetted by the matrix material — the composite strength is decreased with a formal increase in the concentration of the film phase [22-24].

There are no method of forecasting the strength and thermal sensitive asphalt concrete. In this work developing a quantitative assessment influence on the structural-sensitive properties of the composite extensive (an indicator characterizing at the border chapter of phases area) and intensive (an indicator characterizing the influence of physicochemical effects at the border chapter of phases) factors and establishing the mathematical dependence of the thickness structured bitumen layer with the road composite strength is relevant objective.

2. Method and Materials

The mineral fillers considered in the study are distinguished by their mineral composition and physico-mechanical properties. The filler from dolomite MP-1, diatomite of the Inzensky deposit, ground quartz sand Su = 1000 m2/kg were considered. Mineral powder MP-1 meets the requirements of Russian state standard 52129-2003 "Mineral powder for asphalt and organic mixtures. Technical conditions". Diatomite is a sedimentary rock with a highly porous structure formed by the shells (skeletons) of extinct diatoms, which mainly consist of silica hydrates with watering varying degrees. The chemical composition of mineral powders is presented in Table 1.

Table 1. The chemical composition of mineral powders.

Mineral material

Content, % by weight

SiO2

AI2O3

Fe2O3

CaO

MgO

CaCO3+MgCO3

SO3 LOI

MP-1 Diatomite Quartz filler

7.70 82.30 98.72

0.34 5.19 0.67

1.12 2.32 0.07

90.30

0.59 0.33

1.76 0.21

0.57 7.27

The main physic-mechanical properties of mineral powders are presented in Table 2. Table 2. Physic-mechanical properties of mineral powders.

Name of the indicator

Quartz filler

MP-1

Diatomite

Grain composition,% by weight smaller 1.25 mm 0.315 mm 0.071 mm Specific surface area, m2/kg True density, g/cm3

100 100 95.2 1002 2.73

100 99.3 75.5 461 2.82

100 100 97.7 1113 2.11

In the course of work construction bitumen BND 60/90 produced by MOSCOW REFINERY with a softening temperature of 51 °C and a brittleness temperature of -20 °C was used.

The specific surface area and porosity of the mineral powders were determined by nitrogen adsorption at -196 °C according to the Brunauer-Emmett-Teller model (BET) using the pore structure analyzer NOVA 2200e Quantochrome.

The rheological properties of bitumen-mineral mixtures were estimated by viscosity at temperatures of 120, 130, 140 and 150 °C, which was determined using a rotary viscometer MCR 101, Anton Paar with a measuring cell - coaxial cylinders with a constant shear rate of 20 s-1.

Asphalt concrete strength indicators were determined on Samples-cylinders with a diameter and height of 71.7 mm made of crushed stone-mastic asphalt concrete mix SMA-20, corresponding to the requirements of Russian state standard 31015-2002.

The strength of asphalt concrete samples was determined under uniaxial compression at a speed of 3 mm/min at a temperature of 0, 20, 50 °C.

A experimental set and analytical methods has been used in work for quantifying the impact on the structural-sensitive properties of a composite of extensive and intensive factors, calculating the bitumen thickness on the surface of the mineral filler, for establishing a relationship describing the dependence of the thickness structured bitumen layer on the strength of the road composite.

3. Results and Discussion

It is obvious that the film phase content will depend on the area of the phase boundary and the intensity of interaction at this boundary. Formally, these factors influence on the composite property can be written as follows:

F = k k Tm Tn (1)

— geom fm geom fm' ^ '

where Igeom is value characterizing the influence of the extensive factor;

Ifm is value characterizing the influence of the intensive factor;

ki is conversion factors resulting in the units of measurement of the property under investigation F;

m and n are exponents characterizing the intensity of the influence of the factor.

To exclude additional studies related to the search for values ki, the relative changes in properties should be analyzed:

F_

F

f T \m f T \

1 geom V1 geom,0 J

fm

VIfm,0 J

(2)

(here, the subscript "0" denotes the initial parameters).

An important condition for the application this approach is the choice of quantities that characterize the considered extensive (Igeom) and intensive (Ifm) factors. The extensive factor is related to the area of the phase interface and can be represented as a ratio:

1 geom S f

1—=~S~, (3)

geom,0 °f ,0

and the intensive factor is characterized by the intensity of the physicochemical interaction at the border of chapter and, following the work of A.I. Rusanov, can be estimated by the thickness of the layer h:

1 fm _ hfm

T h

fm,0 nfm,0

where Sf is the area of the phase boundary «matrix material - dispersed phase»;

(4)

hfm is the layer thickness of the matrix substance located at the phases border and having properties which differ from similar ones in volume.

Hence the following relationship:

F_

F

f S r f u \

f

Sf ,0 J

h

V J ,0 J V fm,0 J

h

fm

(5)

Calculation Sf by granulometric data is easy:

sf=Z s

m u, j'"j>

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(6)

where Suj, mj specific surface area and content j-th fraction of the dispersed phase.

Determination of hfm is impossible to calculate (especially for complex molecular systems) and is an individual task. Several techniques for determining the thickness of the boundary layer are presented in [11]. It is advisable to apply the rheological method for dispersed systems «bitumen - dispersed phase». It is necessary to assume that an interphase layer is formed on the surface of the particles, consisting of the adsorption and kinetic layers: the kinetic layer characterizes the influence of the particle shape and viscosity of the dispersion medium, and the adsorption layer only the physicochemical dispersed phase activity.

Determining the interfacial layer thickness at the interface of the «bitumen - mineral powder» was carried out according to the method described in [25, 26] the volumetric degree range of mineral filling has been established by this method, at which A. Einstein law is fulfilled, and there is a possibility of calculation for the interfacial layer thickness. The volume content of the dispersed phase is formally increased by Ap, when such a layer is formed. The equation of A. Einstein is represented as:

Vek =n [l + ao + A(P)] or nek =nu + ao%

where nu = no [l + aoVo ] is A. Einstein's equation [26];

no is viscosity of the dispersion environment; ao is spherical particle shape factor (ao = 2.5); po is filler volume share.

The increment of the filler volume share is equal to:

nek (% )-nu

(7)

Acp = -

%ao

(8)

Hence the following relationship:

П 3

(pi = Nf—df and Nf = Nfo

we will have:

Ap = Vo

dL

V df,o J

-1

Interfacial layer thickness is determined by replacing d^ = + 2h and df = 6/ Supf :

h =

Su Pf

nek {% )-По + 1 _ 1 ФоаоПо

(9)

where pf is dispersed phase material density;

Su is specific surface area of the dispersed phase.

Similarly, when taking into account the influence of the particle shape and the adsorption layer on the values of the coefficient a (a > ao):

dL Л

V df,0 J

1

f

acpo

nek (<P0 ) _ 1

V По

\

3

From here:

h =

3

Su Pf

The similar formula is proposed in [12]:

h =

(10)

10

4 f

PS

OL-1

u \am J

(11)

where am is coefficients calculated, respectively, on the basis of measuring the dispersed system viscosity under investigation and the model system "filler - environment", in which the environment does not form at all or forms a solvation shell with negligible thickness on the surface.

The disadvantage of the presented technique is the assumption that the layers formation in different dispersion environments is identical, that is, the comparison in the system behavior is not carried out with the ideal system described by A. Einstein's equation, but with some model system. In addition, certain difficulties arise in the selection of a model dispersion environments (in this case, it is necessary to have an environment with a similar dependence of viscosity in the temperature range under study and lyophobic to the surface mineral component). The implementation of the specified requirements for the dispersion model environment allows to calculating thickness values of the adsorption layer of the dispersion environment.

When using formulas (9) and (10) with the assumption

K = h - hk

(ha - absorption layer thickness; hk - kinetic layer thickness):

ha =

S,

Pf

yiek (Po )-n , 1 _ 3 Wek (Po )-n

(PoaoVo

VoaoVo

(12)

h =

SuPf

aPo

nek (Po )

_ 1

no

_ 3

\apo

n'ek (Po )

n

>

1

J J

(13)

where the index " ' " is used for a model system.

The elimination of this deficiency of the method [25] is possible by the following way. The kinetic layer depends mainly on the dispersion environment viscosity and the particles shape of the dispersed phase. Clearly, dispersion environment viscosity decreases, when the temperature increases. When in the model system rjo ^ 0 (or for a multicomponent dispersion environment rjo ^ Tfamin, hence no,min is viscosity of the highly mobile component) the kinetic layer thickness is hk ^ 0.

A. Einstein equation is being implemented in the range of the dispersed phase volume content ^ [0; 0.05]; therefore, in the work [13], the calculation of layer thicknesses has been carried out with a volume filling degree of 2 %. As dispersed phases was considered mineral powder, the properties of which are presented in Table 3.

Table 3. Mineral fillers properties.

Parameters

Requirements of Russian state standard Quartz filler Limestone Diatomite

Grading, % by weight less 1.25 mm 0.315 mm 0.071 mm Surface area, m2/kg True density, g/cm3

Not less 100 Not less 100 From 70 to 80 Not standardized Not standardized

100 100 95 1002 2.73

100 99 76 461 2.82

100 100 98

1113 2.11

3

The considered mineral powders differ in the specific surface area of the particles, which characterizes the potential area of the interface between the phases and bitumen, along which the physico-chemical interaction processes take place. The dispersed phase type and temperature also affect the system viscosity (Figure 1).

a)

<л 1030

CL.

Ь 1010

О и 990

>

970

950

930

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910

890

870

850

b)

□ Diatom ite ^ Lim estone o Quartz filler

n = Vf+

n = 4319,7 Vf+888.33 n = 2595,4 Vf+884.65

0,015 0.02

Volumetric rate of filler

1100

£ 1000

•es 900 о

и vi

> 800 700 600 500

4nn 300 200 100

□ Diatom ite л Lim estone о Quartz filler

n = 490043e-0052T n = 461308e-0 052T 452882e-0 052T

12n

130

14n

15n

Temperature, oc

Figure 1. Dependence of the dispersion system viscosity: a - from the degree of filling (at T = 120 °C); b - from temperature (at ç = 0.02).

The equation of viscosity as a function of the degree of volumetric rate the approximation is: y = kx + b or according to A. Einstein equation n = arjoç + no, hence k = arjo and b = n, therefore, the angular coefficient characterizing the effect of the dispersed phase is equal to a = k/b. The values of the coefficients are presented in Table 4.

Table 4. The coefficients values of the equations of the viscosity of the dispersed system "bitumen-mineral powder" from the filling degree.

Coefficient

т b a k b a k b a k b a

Temperature, °C

120

Filler

130

140

150

Limestone Diatomite Quartz filler

4319.70 5252.90 2595.40

888.30 897.56 884.60

4.86 5.85 2.93

2109.20 1585.30 1294.10

506.20 510.15 504.62

4.17 3.11 2.56

1222.20 867.95 588.50

307.00 308.39 305.90

3.98 2.81 1.92

687.60 775.50 305.94

194.50 195.36 193.88

3.54 3.97 1.58

According to the obtained experimental dependences of the viscosity of the dispersed system "bitumen - mineral powder", the calculations of layer thicknesses was make: by formulas (9) and (10) - total thickness, and by formulas (12) and (13) - adsorption layer (when conducting the experiment with dispersed the system "castor oil - mineral powder" selected the temperature at which the viscosity of castor oil would correspond to the viscosity of the melt of bitumen) (Tables 5 and 6).

Table 5. The bitumen layers thickness on the surface of the mineral filler (at ao = 2.5).

Filler Total interfacial layer thickness by the formula (9)

120 °C 130 °C 140 °C 150 °C

Limestone 2.690 1.510 1.080 0.192

Diatomite 0.595 -1.708 -2.127 -1.342

Quartz filler 0.777 -0.037 -0.847 -1.661

Filler Total interfacial layer thickness by the formula (12)

120 °C 130 °C 140 °C 150 °C

Limestone 2.690 1.510 1.080 0.192

Diatomite 0.732 -1.572 -1.991 -1.205

Quartz filler 0.790 -0.025 -0.834 -1.649

Table 6. Thickness of the bitumen layer on the surface of the mineral filler (particle shape factor a)._

Total interfacial layer thickness by the formula (10)

Filler -

120 °C 130 °C 140 °C 150 °C

Limestone 0.488 0.413 0.272 0.106

Diatomite 0.387 0.656 0.525 0.041

Quartz filler -0.185 -0.285 -0.385 -0.485

Total interfacial layer thickness by the formula (13)

Filler -

120 °C 130 °C 140 °C 150 °C

Limestone 0.522 0.447 0.306 0.140

Diatomite 0.656 0.625 0.494 0.309

Quartz filler -0.145 -0.245 -0.345 -0.445

Analysis of the thicknesses calculation results of the bitumen layers shows for ideal system (A. Einstein's equation) and the model system that for some powders the thickness values have negative values. This fact is physically absurd, since this is possible only when the filler is dissolved. Negative thicknesses actually indicate the absence of a bitumen layer on the surface of the mineral component (both of the adsorption layer and the kinetic layer).

a) b)

Temperature, °C Temperature, °C

Figure 2. Dependence of the thickness of the adsorption layer of bitumen on temperature:

a - at a = a0; b - at a = a (Table 2).

For determination of the bitumen layer thickness, it is important to determine the temperature at which the kinetic layer thickness is small (hk ^ 0). For it is necessary to determine the minimum bitumen viscosity; under the condition that bitumen is multi-component, is assumed that low viscosity oils provide the minimum viscosity of the bitumen. In this case, as the model of oil, we take the castor oil viscosity (Figure 2). The minimum castor oil viscosity is observed at a temperature 140 °C: n,min = 5.34 mPas. The temperature at which the bitumen has n,min, total T = 220 °C (the calculation was made according to the formula: T* = ln(a/n,min)/b, hence a, b are empirical dependency coefficients n = f(T) (Figure 2).

Data analysis Figure 2 shows that at a temperature T* the bitumen layers thicknesses on the mineral fillers have negative values. This means that no adsorption bitumen layer of significant (definable rheological method) thickness is formed on the surface of the studied mineral components [27].

Estimated temperatures of melts of dispersed systems at which ha(T) = 0 are presented down. The data allow placing of the investigated fillers in a row according to the temperature "sensitivity", assessed by dha/dT: Diatomite (169 °C) > limestone (145 °C) > Quartz filler (101 °C). Moreover T* > 140 °C for the fillers studied (with the exception of quartz filler). It indicates that physico-chemical activity of the filler need to take into account during the asphalt concrete mix preparation and the temperature "sensitivity" - during for compacting the mixture.

Figures 3 show that T > 140 °C for the fillers studied (with the exception of quartz filler). It indicates that physico-chemical activity of the filler need to take into account during the asphalt concrete mix preparation and the temperature "sensitivity" - during for compacting the mixture.

Obtained results and data from [28, 29] show a good convergence and reproducibility of the proposed method for determining the structured bitumen thickness and the physico-chemical activity of the mineral filler.

To determine the influence of the considered extensive (which is related to the area at the border chapter of phases; the exponent is m) and intensive (which is related to the intensity of the physico-chemical interaction at the border chapter of phases; the exponent is n) for this necessary research on the structure-sensitive properties. In accordance with [13], the strength of the composite refers to such properties. Studies were performed by using crushed stone mastic asphalt SMA-20, corresponding to the requirements of Russian state standard 31015-2002 (Table 7).

Table 7. Stone mastic asphalt SMA-20 properties.

Indicator name Requirements of Russian state standard 31015-2002 Actual properties values

Limestone Diatomite Quartz filler

Compressive Strength, MPa (R20) at temperature 20 °C (R50) at temperature 50 °C (R0) at temperature 0 °C more 2.2 more 0.65 not standardized 3.84 5.16 2.62 0.96 2.14 0.67 7.19 5.99 5.42

SMA-20 with limestone powder was control asphalt concrete (Fo depending on (2)).

The data in Figure 2b and Table 7 allow us to make the relationship between the structured bitumen layer thickness and the composite strength. Figure 3 show: asphalt concrete strength increase when thickness ha increase. This dependence has an asymptotic character:

hb *

Vb

ro 8 .c

ею c

c 6

(V

« 5 4 3 2 1 0

О Quartz filler О Diatomite □ Limestone

X miSni'

R = 4.4844ft3-2339 R = 0.5767ft32771 R = 0.1279ft5-5093

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(14)

1.0 1.5 2.0

Thickness of the solvation shell, ^m

Figure 3. Dependence of asphalt concrete strength on the structured bitumen thickness.

Using R(f) = fh) turn out:

R(h) = Rma

h

hma

The presented dependence has a limited scope. It needs verification not only at the top boundary (Rma hmax), but also at the bottom boundary (Rmin, hmin).

The results of the calculation of the exponents n and m of dependence (2) are presented in Table 8.

Table 8. Value n and m calculated according to the formula (2).

The intensity of the influence of parameters

Temperature range, °C Diatomite Quartz filler

m n m n

0...20 0.32 35.34 1.07 0.46

20...50 0.86 17.63 0.77 -0.12

The data from Table 8 show that the main contribution to the concrete structure formation is made by the intensive factor n in SMA-20 with Diatomite, which is responsible for the physical-mechanical interaction of the mineral powder at the border chapter of phases, characterized by the structured bitumen thickness. The main influence on the structure and properties of SMA-20 with quartz filler is exerted by the extensive factor m, which characterizes the influence at the border chapter of phases area.

4. Conclusion

1. Method for calculating of the bitumen layer thickness on the surface of the mineral powders using by the rheological tests results is proposed.

2. A mathematical relationship between the structured bitumen layer thickness and the road composite strength a are established: an increase in the bitumen layer thickness on the surface of the mineral powder leads to an increase in the composite strength.

3. Method for the quantitative assessment of the influence on the structural-sensitive properties of the composite extensive (an indicator characterizing at the border chapter of phases area) and intensive factors are proposed (an indicator characterizing the influence of physico-chemical effects at the border chapter of phases).

4. The extensive factor has a greater effect on the properties of SMA-20 with a quartz filler (m/n > 2). There is a higher rate of decrease in the intensity of physicochemical interactions at the interface of the "oil bitumen-silica filler" phase (index m) as compared with the extensive factor (index n). The different nature of the temperature effect on the extensive and intensive factors is observed for SMA-20 with diatomite: as temperature increased, the factor m is increased, whereas the opposite effect is observed for factor n. It indicates a positive effect of the specific diatomite surface on the temperature asphalt concrete properties. From here follows a technological decision to increase the specific surface area (Ssp) of the diatomite powder used. The latter was realized by treating diatomite powder with a nanoscale modifier, which provided an increase in Ssp in 2.08 times. In [13], it was shown that the use of this nano-modified diatomite powder provided an increase in all indicators of asphalt concrete properties.

References

1. Guo, M., Tan, Y., Wang, L., Hou, Y. A state-of-the-art review on interfacial behavior between asphalt binder and mineral aggregate. Front. Struct. Civ. Eng. 2018. 12(2). Pp. 248-259.

2. Korolev, E.V., Tarasov, R.V., Makarova, L.V., Smirnov, V.A. Model research of bitumen composition with nanoscale structural units. Contemporary engineering sciences. 2015. 8(9-12). Pp. 393-399.

3. Diab, A., Enieb, M. Investigating influence of mineral filler at asphalt mixture and mastic scales. International Journal of Pavement Research and Technology. 2018. 11(3). Pp. 213-224.

4. Macías-Salinas, R., Flores-Granados, M.A., Díaz-Cruz, M., García-Sánchez, F. Modeling the dynamic viscosity of associating and polar fluids via the use of density scaling. Fluid Phase Equilibria. 2018. Vol. 458. Pp. 16-29.

5. Pal, R. Fundamental Rheology of Disperse Systems Based on Single-Particle Mechanics. Fluids. 2016. Vol. 1. No. 4. 40.

6. Radovskiy, B. Analytical Formulas for Film Thickness in Compacted Asphalt Mixture. Transportation Research Record. 2003. No. 1829. Pp. 26-32.

7. Zhang, M., Heitzman, M., Smith, A.E. Improving hot mix asphalt production using computer simulation and real time optimization. Journal of Computing in Civil Engineering. 2014. 28(3). 04014011.

8. Radovskiy, B. Analytical Formulas for Film Thickness in Compacted Asphalt Mixture. Transportation Research Record 1829, TRB, National Research Council, Washington, D.C., 2003. Pp. 26-32.

9. Heitzman, M., Michael, A. Development of new film thickness models for hot mix asphalt. Retrospective Theses and Dissertations. 2005. 1737.

10. Garkina, I.A., Danilov, A.M. Mathematical Methods of System Analysis in Construction Materials. IOP Conf. Series: Materials Science and Engineering. 2017. Vol. 245. 062014.

11. Rusanov, A.I. Termodinamicheskiye osnovy mekhanokhimii [Thermodynamic principles of mechanochemistry]. SPb.: Science. 2006. 221 p. (rus)

12. Rusanov, A.I. Fazovyye ravnovesiya i poverkhnostnyye yavleniya [Phase equilibria and surface phenomena]. SPb .: Chemistry. 1967. 388 p. (rus)

13. Korolev, E.V., Inozemtcev, S.S., Smirnov, V.A. Nanomodified bitumen composites: solvation and rheology. Advanced Materials, Structures and Mechanical Engineering Proceedings of the International Conference on Advanced Materials, Structures and Mechanical Engineering. 2016. Pp. 393-398.

14. Korolev, E.V., Bazhenov, Yu.M., Albakasov, A.I. Radiatsionno-zashchitnyye i khimicheski stoykiye sernyye stroitelnyye materialy [Radiation-protective and chemically resistant sulfur building materials]. Penza, Orenburg: IPK OGU. 2010. 364 p.

15. Jahromi, S.G., Khodaii, A. Effects of nanoclay on rheological properties of bitumen binder. Construction and building materials. 2009. 23(8). Pp. 2894-2904.

16. Poulikakosa, L.D., Tiwari, M.K., Partla, M.N. Analysis of failure mechanism of bitumen films. Fuel. 2013. Vol. 106. Pp. 437-447.

17. Sengoz, B., Agar, E. Effect of asphalt film thickness on the moisture sensitivity characteristics of hot-mix asphalt. Building and Environment. 2007. 42(10). Pp. 3621-3628.

18. Tao, Y.Y., Yu, J.Y., Li, B., Feng, P.C. Effect of different montmorillonites on rheological properties of bitumen/clay nanocomposites. Journal of Central South University of Technology. 2008. 15(1). Pp. 172-175.

19. Hafeez, I., Hussain, J., Riaz, K., Khitab, A., Hussain, S., Zaidi, B., Farooqi, U., Hayat, A., Ahmed, I., Asif, A. Influence of Time and Temperature on Asphalt Binders Rheological Properties. Life Science Journal. 2013. 20(5). Pp. 355-365.

20. Islam, M.R., Tarefder, R.A. Determining thermal properties of asphalt concrete using field data and laboratory testing. Construction and Building Materials. 2014. Vol. 67. Part B. Pp. 297-306.

21. Markanday, S.S., Stastna, J., Polacco, G., Filippi, S., Kazatchkov, I., Zanzotto, L. Rheology of bitumen modified by EVA-organoclay nanocomposites. Journal of Applied Polymer Science. 2010. 118(1). Pp. 557-565.

22. Yangming, G., Yuqing, Z., Fan, G., Tao, X., Hao, W. Impact of minerals and water on bitumen-mineral adhesion and debonding behaviours using molecular dynamics simulations. Construction and Building Materials. 2018. Vol. 171. Pp. 214-222.

23. Meng, G., Amit, B., Yiqiu, T. Effect of mineral fillers adsorption on rheological and chemical properties of asphalt binder. Construction and Building Materials. 2017. Vol. 141. Pp. 152-159.

24. Keith, E. Ensley Multilayer adsorption with molecular orientation of asphalt on mineral aggregate and other substrates. Journal of Applied Chemistry and Biotechnology banner. 2007. 25 (9). Pp. 671-682.

25. Inozemtcev, S.S., Korolev, E.V. Interaction process on the phases interface «bitumen - dispersed phase from cement stone». Magazine of Civil Engineering. 2018. 82(6). Pp. 60-67.

26. Einstein, A. A new determination of molecular dimensions. Annalen der Physik. 1906. 19(4). Pp. 289-306.

27. Willenbacher, N., Georgieva, K. Rheology of Disperse Systems. Nature. 1957. No. 180. Pp. 957-959.

28. Mwanza, A., Hao, P., Wang, H. Effects of Type and Content of Mineral Fillers on the Consistency Properties of Asphalt Mastic. Journal of Testing and Evaluation. 2012. 40(7). 20120140.

29. Wei, J., Yue, H., Aimin, S. A review of eco-friendly functional road materials. Construction and Building Materials. 2018. Vol. 191. Pp. 1082-1092.

Contacts:

Svetlana Shekhovtsova, +7(980)3749704; SHehovtsovaSYU@mgsu.ru Evgenyi Korolev, +7(499)1880400; korolev@nocnt.tu Sergei Inozemtcev, +7(985)2505866; inozemcevss@mgsu.ru Jiangmiao Yu, 18898837614; yujm@scut.edu.cn Huayang Yu, 18898837614; huayangyu@scut.edu.cn

© Shekhovtsova, S.Yu., Korolev, E.V., Inozemtcev, S.S., Yu, J., Yu, H., 2019

Инженерно-строительный журнал

сайт журнала: http://engstrov.spbstu.ru/

ISSN

2071-0305

DOI: 10.18720/MCE.85.11

Методика прогнозирования прочности и термочувствительности асфальтобетона

С.Ю. Шеховцоваa*, ЕВ. Королевa, С.С. Иноземцев3, Д. Юь, Х. Ю*

a Национальный исследовательский Московский государственный строительный университет, г. Москва, Россия

b Южно-Китайский Технологический университет, г. Гуанчжоу, Китай * Е-mail: SHehovtsovaSYU@mgsu.ru

Ключевые слова: дорожное покрытие, асфальтобетон, битум, межфазный слой, реология, экстенсивный и интенсивный факторы, прочность, термочувствительность

Аннотация. Отличительной особенностью композитов является проявление синергетического эффекта вследствие взаимодействия контактирующих веществ на границе раздела фаз, а их интенсивность взаимодействия влияет на объемные свойства композитов. В работе произведено исследование межфазного слоя битума на поверхности минерального порошка. Предложена методика позволяющая, по результатам реологических испытаний, рассчитать толщину граничного слоя в бинарной системе «нефтяной битум - дисперсная фаза». Установлена взаимосвязь, описывающая зависимость толщины слоя структурированного нефтяного битума с прочностью дорожного композита: увеличение толщины слоя битума на поверхности минерального порошка приводит к увеличению прочности композита. Предложена методика для количественной оценки влияния на структурно-чувствительные свойства композита экстенсивного фактора m - показателя, характеризующего влияние площади границы раздела фаз и интенсивного фактора n - показателя, характеризующего влияние физико-химического воздействия на границе раздела фаз. Установлено, что для щебеночно-мастичного асфальтобетона ЩМА-20, изготовленного с применением кварцевого наполнителя более существенное влияние оказывает экстенсивный фактор m/n > 2. Также для него характерна более высокая скорость снижения интенсивности физико-химических взаимодействий на границе раздела фаз «нефтяной битум-кварцевый наполнитель» по сравнению с экстенсивным фактором. Для ЩМА-20, приготовленного с применением диатомита, установлено отличное от симбатного снижения факторов n и m с ростом температуры, установлен различный характер влияния температуры на экстенсивный и интенсивный факторы: при ее увеличении фактор m увеличивается, тогда, как для фактора n наблюдается противоположное влияние. Это свидетельствует о положительном влиянии удельной поверхности диатомита на температурные свойства асфальтобетона.

Литература

1. Guo M., Tan Y., Wang L., Hou Y. A state-of-the-art review on interfacial behavior between asphalt binder and mineral aggregate // Front. Struct. Civ. Eng. 2018. Vol. 12. No. 2. Pp. 248-259.

2. Korolev E.V., Tarasov R.V., Makarova L.V., Smirnov V.A. Model research of bitumen composition with nanoscale structural units // Contemporary engineering sciences. 2015. Vol. 8. No. 9-12. Pp. 393-399.

3. Diab A., Enieb M. Investigating influence of mineral filler at asphalt mixture and mastic scales // International Journal of Pavement Research and Technology. 2018. Vol. 11. No. 3. Pp. 213-224.

4. Macías-Salinas R., Flores-Granados M.A., Díaz-Cruz M., García-Sánchez F. Modeling the dynamic viscosity of associating and polar fluids via the use of density scaling // Fluid Phase Equilibria. 2018. Vol. 458. Pp. 16-29.

5. Pal R. Fundamental Rheology of Disperse Systems Based on Single-Particle Mechanics // Fluids. 2016. Vol. 1. No. 4. 40.

6. Radovskiy B. Analytical Formulas for Film Thickness in Compacted Asphalt Mixture // Transportation Research Record. 2003. No. 1829. Pp. 26-32.

7. Zhang M., Heitzman M., Smith A.E. Improving hot mix asphalt production using computer simulation and real time optimization // Journal of Computing in Civil Engineering. 2014. Vol. 28. No. 3. 04014011.

8. Radovskiy B. Analytical Formulas for Film Thickness in Compacted Asphalt Mixture // Transportation Research Record 1829, TRB, National Research Council, Washington, D.C., 2003. Pp. 26-32.

9. Heitzman M., Michael A. Development of new film thickness models for hot mix asphalt. Retrospective Theses and Dissertations. 2005. 1737.

10. Garkina I.A., Danilov A.M. Mathematical Methods of System Analysis in Construction Materials // IOP Conf. Series: Materials Science and Engineering. 2017. Vol. 245. 062014.

11. Rusanov A.I. Termodinamicheskiye osnovy mekhanokhimii [Thermodynamic principles of mechanochemistry]. SPb.: Science. 2006. 221 p. (rus)

12. Rusanov A.I. Fazovyye ravnovesiya i poverkhnostnyye yavleniya [Phase equilibria and surface phenomena]. SPb.: Chemistry. 1967. 388 p. (rus)

13. Korolev E.V., Inozemtcev S.S., Smirnov V.A. Nanomodified bitumen composites: solvation and rheology. Advanced Materials, Structures and Mechanical Engineering Proceedings of the International Conference on Advanced Materials, Structures and Mechanical Engineering. 2016. Pp. 393-398.

14. Korolev E.V., Bazhenov Yu.M., Albakasov A.I. Radiatsionno-zashchitnyye i khimicheski stoykiye sernyye stroitelnyye materialy [Radiation-protective and chemically resistant sulfur building materials]. Penza, Orenburg: IPK OGU. 2010. 364 p.

15. Jahromi S.G., Khodaii, A. Effects of nanoclay on rheological properties of bitumen binder // Construction and building materials. 2009. Vol. 23. No. 8. Pp. 2894-2904.

16. Poulikakosa L.D., Tiwari M.K., Partla M.N. Analysis of failure mechanism of bitumen films // Fuel. 2013. Vol. 106. Pp. 437-447.

17. Sengoz B., Agar E. Effect of asphalt film thickness on the moisture sensitivity characteristics of hot-mix asphalt // Building and Environment. 2007. Vol. 42. No. 10. Pp. 3621-3628.

18. Tao Y.Y., Yu J.Y., Li B., Feng P.C. Effect of different montmorillonites on rheological properties of bitumen/clay nanocomposites // Journal of Central South University of Technology. 2008. Vol. 15. No. 1. Pp. 172-175.

19. Hafeez I., Hussain J., Riaz K., Khitab A., Hussain S., Zaidi B., Farooqi U., Hayat A., Ahmed I., Asif A. Influence of Time and Temperature on Asphalt Binders Rheological Properties // Life Science Journal. 2013. Vol. 20. No. 5. Pp. 355-365.

20. Islam M.R., Tarefder R.A. Determining thermal properties of asphalt concrete using field data and laboratory testing // Construction and Building Materials. 2014. Vol. 67. Part B. Pp. 297-306.

21. Markanday S.S., Stastna J., Polacco G., Filippi S., Kazatchkov I., Zanzotto L. Rheology of bitumen modified by EVA-organoclay nanocomposites // Journal of Applied Polymer Science. 2010. Vol. 118. No. 1. Pp. 557-565.

22. Yangming G., Yuqing Z., Fan G., Tao X., Hao W. Impact of minerals and water on bitumen-mineral adhesion and debonding behaviours using molecular dynamics simulations // Construction and Building Materials. 2018. Vol. 171. Pp. 214-222.

23. Meng G., Amit B., Yiqiu T. Effect of mineral fillers adsorption on rheological and chemical properties of asphalt binder // Construction and Building Materials. 2017. Vol. 141. Pp. 152-159.

24. Keith E. Ensley Multilayer adsorption with molecular orientation of asphalt on mineral aggregate and other substrates // Journal of Applied Chemistry and Biotechnology banner. 2007. Vol. 25. No. 9. Pp. 671-682.

25. Inozemtcev S.S., Korolev E.V. Interaction process on the phases interface «bitumen - dispersed phase from cement stone» // Magazine of Civil Engineering. 2018. Vol. 82. No. 6. Pp. 60-67.

26. Einstein A. A new determination of molecular dimensions // Annalen der Physik. 1906. Vol. 19. No. 4. Pp. 289-306.

27. Willenbacher N., Georgieva K. Rheology of Disperse Systems // Nature. 1957. No. 180. Pp. 957-959.

28. Mwanza A., Hao P., Wang H. Effects of Type and Content of Mineral Fillers on the Consistency Properties of Asphalt Mastic // Journal of Testing and Evaluation. 2012. Vol. 40. No. 7. 20120140.

29. Wei J., Yue H., Aimin S. A review of eco-friendly functional road materials // Construction and Building Materials. 2018. Vol. 191. Pp. 1082-1092.

Контактные данные:

Светлана Юрьевна Шеховцова, +7(980)3749704; эл. почта: SHehovtsovaSYU@mgsu.ru Евгений Валерьевич Королев, +7(499)1880400; эл. почта: korolev@nocnt.tu Сергей Сергеевич Иноземцев, +7(985)2505866; эл. почта: inozemcevss@mgsu.ru Джиангжмиао Ю, 18898837614; эл. почта: yujm@scut.edu.cn Хуаянг Ю, 18898837614; эл. почта: huayangyu@scut.edu.cn

© Шеховцова С.Ю., Королев Е.В., Иноземцев С.С., Ю. Д., Ю. Х., 2019

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