1

Research on Alternatives for Tar-containing Antiskid Surface

Zhao Su, Ludo van Duuren, Wietze Giezen, Frits Zandvoort

Icopal B.V

Abstract

The present paper deals with the research and development on alternatives for the tar-

containing antiskid surface. The antiskid binder is the key issue of the antiskid surface. 3

types of 2-component epoxy bitumen binder have been developed for this purpose. This paper

presents and discusses the results of the pure binders, such as strength and strain development,

flexibility, relaxation behaviour, water-vapour permeability, rheological property and ageing

resistance. Based on the results of the pure binders, one type of epoxy bitumen binder is

selected to build up the antiskid surface. The test results demonstrate that the antiskid surface

fulfils all the requirements of the specification, such as the macro-texture, high adhesion/shear

strength and excellent skid resistance shown by the actual field test.

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1. Introduction

Antiskid surfacing is a type of thin surfacing construction layer, the function of which is to

offer adequate skid resistance and ensure excellent bond strength to the underneath pavement

surface. In the Netherlands, most of the airfield runways used tar-containing binders in

combination with 1-3 mm fraction of mineral aggregates as an antiskid surfacing. Unlike

bitumen based materials, the tar-containing surface layer, is inherently resistant to chemicals

(oils) and can provide an excellent adhesive property to the mineral aggregates and asphalt

pavement thanks to its unique chemical and molecular structure of refined tar. However, the

tar-containing binder is toxic and carcinogenic because of its high Polycyclic Aromatic

Hydrocarbons (PAHs) content.

Since July 1999, the use of road construction materials containing more than 75 mg/kg of the

10 most dangerous Polycyclic Aromatic Hydrocarbons (PAH) has been banned by the Dutch

law, but with an exception of coatings on airfield pavements in a Royal Decision on PAH

(April 6th, 1998). Based on this decision, it was still more or less common practice in the

Netherlands to use the traditional tar-containing antiskid on runways and rapid exits on both

military and civil airfields. Since 2013, the traditional tar-based antiskid has been not totally

allowed anymore by airport authorities in order to minimise the health risk and environmental

impact [1].

As a result, a study group was established in 2009, with the goal to develop specifications for

runway surface dressings on airfields, including the demands for quality control before,

during and after application. This research led to a successful PhD project, promoted at TU

Delft in August 2013 [2]. The key issue was to find out an alternative binder, which does not

only show good mechanical properties, but also will not contain dangerous components in

quantities higher than allowed by the national law. Furthermore, the antiskid surface, binder

in combination with mineral aggregates, has to fulfil the functional requirements, such as the

texture, skid resistance, adhesion and shear strength, resistance to chemicals / high

temperature, and durability. It is obviously that the virgin bitumen and even heavily polymer-

modified bitumen can not fulfil these requirements [3]. The major problems arising from

bituminous binder concern the oil and chemical resistance, mechanical properties at elevated

temperature, as well as the flexibility at a low temperature. In general, the stronger the binder

is, the less flexible it is, and it is thence more liable to cracking. A novel and innovative

binder has to be developed.

As an industrial partner, Icopal BV joined this study group and conducted a close cooperation

with TU Delft, by offering her technical advice and support, as well as her innovative epoxy-

modified bitumen binder (EshaSeal 2C antiskid) [5].

Epoxy bitumen is a kind of strong and durable adhesive binder, formed by a chemical reaction

of the modified bitumen with the curing agent at ambient temperature. The product shows a

three-dimensional cross-linking structure of epoxy resin interwoven integrally with adhesive

bitumen components. Therefore it combines the advantages of strong epoxy resin with

adhesive bitumen, demonstrating not only excellent mechanical/flexible properties,

thermal/chemical resistance and durability, but also very strong adhesion properties to various

subtracts, such as asphalt, cement concrete, mineral aggregates and metal.

This paper will present and discuss some of the results, for both the pure binder and antiskid

surface layer, and finalise with a very successful field friction test.

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2. Development of alternative binder for tar-containing antiskid

2.1 Epoxy chemistry

Basic epoxy resin is a medium viscosity liquid compound produced from bisphenol A and

epichlorohydrin. The typical structure is shown in Figure 1.

Figure 1: A typical structure of epoxy resin

The epoxy resin can react with a wide range of co-reactants including polyfunctional amines.

These co-reactants are often referred to as hardeners or curing agents. The reaction of

polyepoxides with polyfunctional hardeners forms a thermosetting polymer (hardened epoxy),

often with high mechanical properties, temperature and chemical resistance [4]. Epoxy has a

wide range of applications, including metal coatings, electrical components, and fibre-

reinforced plastic materials in civil engineering. A typical epoxy resin / amine hardening

reaction mechanism can be explained by the diagram in Figure 2.

Figure 2: A typical epoxy resin / amine hardening reaction mechanism

2.2 Two-Component Epoxy Modified Bitumen Epoxy and bitumen are completely different materials. The goal behind the modification is to

achieve a sort of binder with favourable properties from both epoxy resin and bitumen

compounds. It is well known that epoxy has an excellent property regarding mechanical

strength, adhesion to various substrates, fuel and temperature resistance, but maybe too stiff

and brittle in some cases; whereas bitumen shows a good visco-elastic property, but rather

susceptible to temperature, fuel and solvent in most cases.

It is well known that the epoxy is a very strong, but less flexible material in general. From the

polymerisation point of view, it is possible to sacrifice some mechanical strength (not always

necessary such high), and gain extra flexibility (desirable) by reducing the number of cross-

linking reaction points in the chemical chains. Based on this idea, 3 types of epoxy bitumen

have been developed, for a test to see which type is more suitable for an antiskid binder.

Table 1 presents 3 types of products to be tested. It is important to keep in mind that the

selection of a flexible antiskid binder must fulfil both mechanical properties (i.e. the shear

strength between the new antiskid layer and existing asphalt, as well as the adhesion between

the two layers) and functional requirements (such as surface texture, temperature and fuel

resistance, etc).

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Table 1: Technical information of epoxy bitumen I

Properties Component A Component B

Appearance Viscous liquid Viscous liquid

Colour Black Yellowish

Type Type A1 Type A2 Type A3 Only 1 Type

Viscosity mPa·s at 25 °C 7500 6700 6300 0,40 ± 0.10

Density g/ml 1,28 1.30 1.37 1,0 ± 0,1

Mass ratio (A to B) 85.5 to 14.5 86.0 to 14.0 86.5 to 13.5 Component B is

used for all 3

types of

Component A

Properties of Component A + B

Curing speed High Middle Low

Mechanical strength High Middle Low

Flexibility Low Middle High

Besides epoxy and bitumen, the filler also plays an important role, concerning the

compatibility between bitumen and epoxy, the workability and even with some thixotropic

property, which is also important in the application, to prevent the material from dropping

down into voids before getting hard.

The epoxy resins were carefully selected to achieve proper mechanical properties and

excellent compatibility with bitumen without phase separation. The hardening mechanism is

based on a chemical reaction between component A (modified bitumen) and B (curing agent)

after mixing, leading to a 3-dimensional cross-linking structure of epoxy resin, integrally

interwoven with a bitumen matrix. Therefore, the mixture shows the advantages of both

epoxy resin and bitumen binder.

The epoxy bitumen is composed of bitumen compatible epoxy resin, bitumen and additive, as

well as mineral filler. Component A is a type of modified bitumen, composed of bitumen,

polar reactive epoxy resin, filler and vegetable oil as a plasticizer.

3. Test conditions

Test conditions are described in literature [2], unless it is specified in this paper.

4. Test Results and Discussions

4.1 Effect of curing temperature on the strength development of epoxy bitumen The strength is a very important parameter for antiskid binder. Figure 3 presents the results,

showing effect of curing temperature on the strength and strain development of 3 types of

epoxy bitumen mixtures (redrawn from Reference 2). The results clearly demonstrate that:

a. The higher the curing temperature, the faster the strength development, particularly at the

early curing stage;

b. With increasing curing time, the tensile strength increases, whereas the strain decreases,

but the temperature influence is less, meaning that the curing process becomes more

mature;

c. After 24 hour curing, the epoxy bitumen can reach 80 - 90% of its ultimate strength, which

is much higher than that of highly modified bitumen [6]. The high early strength is to

ensure a fast construction process and early reopening of the runway to aircrafts;

d. The ultimate strength of A1, A2 and A3 mixture is ca. 16, 12 and 8 MPa, whereas the

strain level is 4, 10 and 60%, respectively

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(A) Strength development (B) Strain development

Figure 3: Effect of curing temperature on the strength and strain development

4.2 Relaxation behaviour of epoxy bitumen

One type of antiskid damage is cracking and detaching from the asphalt surface. The potential

antiskid binder should not only have a high level strength and flexibility, but also a good

behaviour of relaxation property, which is to be able to sustain the combination of induced

stresses due to travelling and braking of aircrafts, variation of environmental circumstances,

such as temperature (day and night, summer and winter) and moisture (drying and raining

weather cycles). Thus the cracking chance of the antiskid layer will be minimised. In general,

the relaxation behaviour is very much dependent on the characteristics of the binder.

Epoxy bitumen is visco-elastic in nature. As the displacement is fixed, the stress generated in

the binder will initially decrease sharply, then gradually to a constant level with time. After a

certain period of time, the remaining stress will stay constant at a low level. The relaxation

property of purely elastic materials is 0%, while for purely viscous materials it is 100%.

Table 2 shows the results of relaxation behaviour of 3 types of epoxy bitumen binder. A

constant loading rate of 10 mm/minute was applied till a certain force was reached, say 40%

of the failure force of fully cured samples. Afterwards, the displacement was kept as a

constant for 10 minutes and the relaxation of the resulting force was monitored against time.

The relaxation property is improved with increasing the temperature during the test, i.e. the

higher the test temperature, the higher the percentage of stress relaxed. Even at 0ºC, the

relaxation of stress is 28.72%, 42.33% and 72.51% for binder A1, A2 and A3, respectively.

The higher the temperature, the higher the relaxation value is. The results show that the stress

generated inside the binder can mitigate with time, the cracking chance is thus reduced.

Table 2: The relaxation behaviour of 3 types of epoxy bitumen mixtures [2]

Temperature (ºC) Binder A1 (%) Binder A2 (%) Binder A3 (%)

0 28.72 42.33 72.51

10 42.03 73.39 91.35

20 80.40 94.69

4.3 Rheological performance of epoxy bitumen

Figure 4 shows the master curves of the complex shear modulus and phase angle for the A1,

A2 and A3 binders compared with that of binder from MBE (modified bitumen emulsion), at

a reference temperature of 20°C [2]. The property at a lower and higher frequency range

represents material behaviour at a higher and lower temperature range, respectively.

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Figure 4: Master curves of the complex shear modulus and phase angle of epoxy bitumen [2]

The results demonstrate that the complex shear modulus and phase angle of epoxy bitumen

binder are completely different from that of binder MBE. Binder A3 shows a comparable

modulus as A1 and A2 (with an identical modulus at the whole frequency range) at higher and

lower frequency range, but a much lower complex modulus in the middle range. This could

be due to more flexible epoxy in combination with viscous bitumen. The result also reveals

that the modulus of each epoxy bitumen binder is not only much higher that that of MBE

binder, but also with a lower slope than that of MBE binder. This is particularly the case at the

lower and higher frequency range, where the modulus is almost constant, meaning that the

material behaviour is not influenced by temperature.

Binder A3 has a lower complex modulus, whereas A1 and A2 binder have similar master

curves of modulus and phase angle. Binder A3 shows lower complex shear modulus than that

of A1 and A2, which are identical in the whole range of the frequency, but it is much higher

that that of MBE binder. The modulus of epoxy bitumen binder at low frequency range is

even higher than 2 MPa, ca. 1000 times higher than that of MBE binder. The maximum shear

modulus of epoxy bitumen binders and MBE binder is around 109 and 108 MPa, respectively

(10 times difference) at the higher frequency range. This means that the epoxy bitumen binder

is much stronger, but less temperature susceptible than MBE binder.

The phase angle curves of epoxy bitumen binders are totally different from that of MBE

binder. The phase angle curves of epoxy bitumen binders have a distinct peak value at a

certain frequency. This could be due to the combining effect of elastic behaviour of epoxy and

viscous behaviour of bitumen material. In contrast, the phase angle curve of the MBE binder

keeps increasing with decreasing frequency. The phase angles of all 3 types of epoxy bitumen

are much lower than that of the MBE binder, meaning that they behave more elastically.

Taking into account the strength development, relaxation behaviour and rheological

properties of 3 types of epoxy bitumen binders, binder A3 appears to be a promising

candidate for further research work. Therefore, the research is from now on focused on binder

A3, known as EshaSeal 2C.

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4.4 Ageing resistance of epoxy bitumen binder

In order to understand the effect of ageing on the properties of epoxy bitumen binders, A3

binder was selected to run ageing test in combination with 3 types of anti-oxidation agents,

known as HALS (Hindered Amine Light Stabilizer). The mixture composition is presented in

Table 3. The dimension of the samples for ageing tests is thin sheets (150x50x3mm).

Furthermore, the cured samples (2 weeks at ambient temperature) are subjected to 2 types of

ageing regimes, i.e. high temperature ageing (at 70ºC for 2 weeks) and UV ageing (at UV-

A340nm 45W/m2 at 50°C for 4 weeks). The aged samples were then subjected to ZWICK-

1445 machine to measure the tensile strength and strain at 23ºC, with a loading speed of

10mm/min. The tensile strength and strain were measured to evaluate the aging properties.

Table 3: Mixture compositions for ageing test (pure A3 binder used as a reference)

HALS Type Sample code

Ref.

(A(A LB-05 LB-10 LB-15 T5-05 T5-10 T5-15 T4-10 TT-05

LB1260 0.5% 1.0% 1.5%

Tinuvin 5100 0.5% 1.0% 1.5% 0.5%

Tinuvin 400 1.0% 0.5%

LB1260 (Lowilite UV B1260) supplied by Chemtura, Tinuvin 5100 and Tinuvin 400 by BASF

Note: Ref. = pure A3 binder, the rest contains different type and amount of HALS

Figure 5 shows the effect of aging conditions on the tensile strength and strain of epoxy

bitumen binders, respectively. The samples contain different types and dosages of anti-

oxidation agents. The results in Figure 5 (A) clearly show that the high temperature ageing at

70ºC for 2 weeks has a remarkably positive influence on the tensile strength, significantly

increasing after ageing. The high temperature probably promotes the epoxy to react to a more

mature degree, demonstrated by further tensile strength development. The results also reveal

that UV-ageing has also a positive effect on the tensile strength development. This could be

also due to the elevated temperature (at 50°C for 4 weeks) effect during the UV ageing test.

Although the UV radiation is known to cause bitumen aging, this is only a surface

phenomenon. Bitumen itself has a strong UV-absorbing behaviour, and as seen in i.e. APP

(atactic polypropene) modified bitumen, used in roofing membranes [11], the polymer

backbone (epoxy network) could have a synergy with the UV-blocking bitumen. Therefore

the HALS effect seems to be negligible. In general, the aging process, particularly high

temperature ageing, shows a positive effect with respect to the tensile strength development.

(A) Tensile strength (B) Tensile strain (flexibility)

Figure 5: Effect ageing on the tensile strength and strain

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The results in Figure 5 (B) indicate that high temperature ageing has also a positive influence

on the tensile strain development, whereas in the case of UV ageing condition, this effect is

very limited. The tensile strain is around 90% in all cases, meaning that the epoxy bitumen

remains flexible to any ageing condition exposed.

Xiao performed DSR tests, finding out the effect of ageing tests on the rheological properties

of A3 binder with 1% of Lowilite UV B1260 UV. Figure 6 compares the master curves of the

complex shear modulus of the original binder, the oven-aged and UV-aged binder,

respectively [2]. The modulus by DSR test is another representation of the material’s response

behaviour. The results manifest the ageing increases the complex shear modulus, the high

temperature ageing has even more significant effect than UV ageing on the complex shear

modulus. This finding is in very good agreement with the present result.

Figure 6: Effect of ageing regimes on the complex shear modulus of A3 binder [2]

The UV stabilizer is a Hindered Amine Light Stabilizer (abbreviated as HALS). It is known

that the hardener of epoxy is an amine-based chemical, which is sensitive to light and UV

radiation. As a result, the epoxy may get degraded and show loss of mechanical properties.

HALS does not absorb UV radiation, but also inhibit the degradation of the polymer. HALS is

a particularly important additive in a thin layer coating (in a micron level) industry, for

example in the automobile manufacturing industry. In the case of antiskid application, HALS

does not play a crucial role as shown in this study, probably due to:

* The antiskid layer is in a level of millimetre, instead of micron thickness. The degradation

occurs only on the surface by weathering ageing regime, demonstrated by (a) loss of

bitumen film from the sample surface (colour change from grey to black) [2]; (b)

maintaining the most part of strength and strain after ageing.

* Beneficial effect of epoxy in combination with bitumen and filler: (a) protect epoxy by

bitumen film (dark colour) from light radiation; (b) cut UV radiation beam and reflect it

back by filler particles.

4.5 Water-vapour permeability of epoxy bitumen

The water vapour permeability of the material is equal to the mass of water that diffuses

through the material per unit of time and per unit of area of material per unit pressure

difference. In contrast, the water vapour resistance expresses the ability of the material NOT

to permit a substance to pass through it. Two parameters are important for concerning the

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water vapour permeability. One is the equivalent air layer thickness (Sd), indicating the

thickness of a motionless air layer that has the same water vapour resistance as the material of

thickness D; the other is the water-vapour resistance factor (µ), indicating how many times

greater the water-vapour resistance of a material as compared with a layer of static air of the

same thickness at the same temperature and pressure. Equation 1 applies for the water vapour

diffusion equivalent air layer thickness (Sd) of a building material:

Sd = µ * S (m) (1)

Where: Sd - the thickness of a static layer of air in metres

S - the thickness of the material (m)

µ - the water-vapour resistance factor (a material inherent constant)

Ranges of Sd values: Sd ≤ 0.5 m => diffusion-open

Sd > 0.5 m => diffusion-blocking

Sd ≥1500 m => diffusion-proof

The water-vapour permeability is determined according to EN 7783: 2011 using wet-cup

method at 23ºC [7]. This is the most convenient manner of carrying out determinations of

water-vapour permeability under conditions of high relative humidity (between 93 % and

50 %). Table 3 presents the test results, i.e. Sd values and µ values compared with oxidised

bitumen and heavy-modified bitumen, respectively [8, 9].

Table 3: The water-vapour resistance factor of epoxy bitumen as compared with bitumen

Samples

ca. 1 mm ca. 2 mm

1 2 3 1 2 3

Thickness (mm) 1.23 1.12 1.28 2.15 2.53 2.16

Vapour transmission rate (g/m2/day) 3.91 4.13 3.26 1.64 1.54 2.59

Equivalent air layer thickness (m) 8.1 5.7 7.3 14.4 15.4 9.2

Vapour resistance factor (µ) 6700 4700 6000 5800 6300 6700

Average µ value 5,800 5,700

Oxidised bitumen 10,000

Heavy-modified bitumen 20,000

As shown in Table 3, the µ values both for 1 and 2 mm thickness of samples are around

5800, which is much lower that that of oxidised and heavy-modified bitumen, 10000 and

20000, respectively [9]. Furthermore, Sd valves for 1 and 2 mm thickness of epoxy bitumen is

about 7 and 14 metres, respectively, meaning that the epoxy bitumen is in the range of vapour

diffusion blocking, instead of diffusion proof. The vapour resistance factor demonstrates that

epoxy bitumen is more vapour permeable than bitumen binder, which means less risk for

generation of air blisters under the antiskid layer by persistent water vapour pressure. It has to

be realised however that the sample preparation plays a crucial role for the test results, for

example, the evenness of the sample thickness. The vapour always tries to find a weak path to

escape.

4.6 Macro texture of antiskid surface

Epoxy bitumen A3 in combination with crushed mineral aggregates (1-3 mm) was selected

for the design of a new antiskid surface. The reasons for this were that it has a high tensile

strength, the best relaxation behaviour, better high temperature ageing resistance and better

UV resistance compared to the other binders.

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The texture depth of the antiskid layer is important for the skid resistance and water drainage

property on the runway. The measured texture depth of the antiskid surface is 1.81 mm [2],

which is higher than the specification-required minimum value of 1.25 mm [3].

4.7 Bonding strength of antiskid layer to asphalt underneath

The bonding strength includes the adhesion and shear strength through the interface between

the antiskid layer and the asphalt underneath. The adhesion strength was determined by means

of a pull test [2]. The tests were conducted at three temperatures (0ºC, 10ºC and 20ºC) at a

fixed loading speed of 0.025 MPa/s. The shear strength was also investigated at these 3

temperature conditions by means of Leutner shear tester at a displacement rate of 50 mm/min.

The test results are presented in Table 3.

Table 3: Adhesion and shear strength of the antiskid layer to the asphalt underneath [2]

Temperature

(ºC)

Adhesion

strength

(MPa)

Average

value

(MPa)

Required

value

(MPa)

Shear

Strength

(MPa)

Average

value

(MPa)

Required

value

(MPa)

20

1.41

1.40

3.45

3.37 1.2 1.51 2.97

1.28 3.71

10

2.24

2.50 1.0

6.04

5.96 2.75 5.72

6.11

0

2.27

2.51

6.34

6.97 2.25 6.72

3.02 7.86

The adhesion strength is 1.40, 2,50 and 2.51 MPa at 20, 10 and 0 ºC; whereas the shear

strength is 3.37, 5.96 and 6.97 MPa at these 3 temperatures, respectively. The adhesion

strength is much higher than the required (2.50 MPa >1.0 at 10ºC), so is the shear strength

(3.37 MPa >1.2 at 20ºC) [3].

It should be emphasised however that all the failures occurred through the asphalt mixture

below the interface. This implies that the obtained adhesion strength actually represents the

tensile strength of the asphalt mixture, instead of the actual adhesion strength at the interface.

Therefore, the asphalt mixture is the weakest area in this construction. In case any damage

may occur on the runway, it could be first in the asphalt in stead of the antiskid surface.

4.8 Field skid resistance

A test section (100x4m) of antiskid surface was laid at Airbase Woensdrecht at the end of

October 2013 (contracted by Frans Nooren BV). The dosage of epoxy bitumen and mineral

aggregates (1-3 mm) is 2,0-2,5 kg and 8-10 kg, respectively. The application process

includes: (a) Mixing epoxy bitumen two component binder; (b) Spreading the binder

homogeneously on the asphalt surface; (c) Spraying right amount of minerals on the binder;

(d) Compaction with a rubber-tire roller, and then (e) Removal of loose-lying minerals when

the binder is fully cured.

The construction of the antiskid layer and field skid resistance test are shown in Figure 6 and

Figure 7, respectively. The measurement diagram and detail texture are shown at the left-

down corner of Figure 7. The measured friction value almost reaches the maximum the scale

of the apparatus.

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Figure 6: Construction of antiskid layer

Figure 7: Field skid resistance test

The friction measurements were carried out with a Sarsys Surface Friction Tester (SSFT) at a

speed of 65 km and 95 km per hour [10]. Table 4 presents the test results, compared with

NATO STANAG 3634 and ICAO Annex 14. The ICAO recommendations are used in civil

aviation, whereas the STANAG is used by NATO. The average friction is 0.98 and 0.94,

respectively. The measured values are even far above the design objective (conception level)

of 0.82 and 0.74, respectively. This means that the friction level of the section with EshaSeal

2C epoxy bitumen in combination with Basalt 1-3mm aggregates can be classified as

“GOOD”, and satisfies the requirements of NATO STANAG 3634 and ICAO Annex 14 [10].

Table 4: Measured friction results compared with STANAG 3634 & ICAO’s required value

Measurement speed (km/hour) 65 95

Direction Rwy 07 Rwy 25 Rwy 07 Rwy 25

Friction values measured 0.98 0.97 0.95 0.93

Friction average 0.98 0.94

STANAG 3634

& ICAO’s

required value

Design objective 0.82 0.74

Maintenance level 0.60 0.47

Minimum level 0.50 0.34

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5. Conclusions

1). EshaSeal 2C is a visco-elastic binder, demonstrating fast strength development, good

relaxation behaviour and excellent rheological properties, it has much higher strength and

strain value, as well as less susceptible to temperature (low phase angle, particularly at

low and high frequency) as compared with modified bitumen binder.

2). EshaSeal 2C is temperature- and UV-ageing resistant. The high temperature ageing has a

positive influence on the tensile strength and strain development, probably due to the fact

that the high temperature promotes the epoxy to react to a more mature degree. This

finding also applies to UV ageing, in which the temperature is maintained at 50ºC.

3). HALS has no significant effect on the UV-ageing process. The bitumen, epoxy resin and

filler probably have beneficial effect; by protecting each other from UV radiation.

4). The adhesion strength between EshaSeal 2C antiskid layer and asphalt is remarkable

higher than the tensile strength of the asphalt itself.

5). EshaSeal 2C is more water-vapour permeable than bitumen and modified bitumen binder.

6). EshaSeal 2C antiskid surface shows excellent friction values, much higher the design

objective (conception level) by NATO STANAG 3634 and ICAO Annex 14.

In general, EashSeal 2C is a strong and flexible binder, the EshaSeal 2C antiskid surface

fulfils all the requirements of the specification, such as the macro-texture, adhesion/shear

strength and excellent skid resistance shown by the field test. EshaSeal 2C also demonstrates

excellent fuel resistant property. The results were presented elsewhere [12].

References 1. Leest, A.J.v. et al, Resistance of surface layers on airfields in the Netherlands-in situ and

laboratory testing, in 2005 European Airport Pavement Workshop. 2005.

2． Xiao Y., Towards a Performance Evaluation Method for Durable and Sustainable Thin

Surfacings, PhD dissertation, TU Delft, ISBN 978-94-6186-186-3, 08-2013

3. CROW-report D13-04, Specifications and Test Protocols for Non-toxic Runway Surface

Dressings on Airfields, 09- 2013

4. Maureen A. et al, Epoxy Resins, ASM Handbook, Vol. 21: Composites, p78-89, 2001

5. Xiao Y. et al, Characteristics of two-component epoxy modified bitumen, Materials and

Structures 44: 611–622, 2011

6. The Modified Asphalt Research Centre, http://uwmarc.wisc.edu/binder-bond-strength

7. European Standards, NF EN ISO 7783, Determination of water-vapour transmission

properties, 2011

8. Cottereau S. et al, Determination of water-vapour transmission properties of Esha Seal

2C epoxy-bitumen, Icopal Group RD report, 2014

9. Zandvoort F. Dampdiffusieweerstand van Dakbedekking, Icopal Group RD report, 1995

10. Stet A., Surface Friction Measurement of Skid Layer of EshaSeal 2C Epoxy Bitumen

with Basalt 1-3mm Airbase Woensdrecht the Netherlands, No. 2013-140, 2013

11. Zandvoort F. Onderzoek naar de Oorzaken van Craquelé, Esha Report, 1990

12. Su Z., Fuel Resistance of EshaSeal 2C, Icopal Research Report, 2014

Acknoledgements

Authors like to express their gratitude to Dr. Xiao for his permission to present part of

his PhD research results at TU Delft. The acknowledgement also goes to Frans Nooren BV

for construction of the antiskid test section at Airbase Woensdrecht.