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Developed as alternative for thin layer concrete pavement or semi-flexible pavement in tunnels, it is a durable bright colored hot mix asphalt mixture using white ceramic aggregates, white pigment and special binder. As special binder, epoxy-resin+de-colorized binder combination or modified de-colorized asphalt are used depending on traffic volume.
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Pavement surface | |
| 1 | : Using white ceramic aggregates, special binder, less abrasion by tire chain and long durability are actualized. Especially, using the combination of epoxy-resin and de-colorized binder, surface abrasion becomes one fifth of concrete pavement (a survey result on existing road). | | 2 | : Using white ceramic aggregates and white pigment, it shows excellent bright color. | | 3 | : The construction procedure is the same with ordinary asphalt pavement with no need of curing, thus construction period can be decreased. | | 4 | : No need of joints even on concrete slabs, thus enabling smooth ridability. | |
| 1 | : As surface course in tunnels (especially at problematic regarding abrasion by tire chains). | | 2 | : At where discrimination from ordinary traffic lanes is desirable (i.e. ramps of expressway, intersections). | |
| An Example of Construction | |
 | [Before]
Rutting caused by rutting
 | | [After] After milling up to the depth of rutting (5 cm), over laid by W-White.
 | (1) W-White does not require cutter joint at matching the joint of existing concrete slab.
(2) The gradation of W-White is the same as Stone Matrix Asphalt (SMA).Fig.-1 Typical pavement structure | |
| An Example of Aggregate Mix Design | |
Table-1 An example of mixture design for W-White unit:%Example
No. | White ceramic
#6 | Crushed Sone
#6 | Crushed Stone
#7 | Coarse Sand | Crushed Sand | Filler | White Pigment | Total | | 1 | 37.0 | 17.0 | --- | 38.0 | --- | 7.0 | 1.0 | 100 | | 2 | 25.0 | 46.0 | 6.0 | 5.0 | 5.0 | 12.0 | 1.0 | 100 | | standard | 25-40 | --- | --- | --- | --- | --- | 1-2 | --- | | #1: | At mixture design example 1, a combined binder of epoxy resin (35 %) and de-colorized binder (35 %) was used. | | #2: | At the mixture design example 2 modified and de-colorized binder was used. | | #3: | Plant fibre was added by the content of 0.3 % weight of Mixture weight. | | #4: | The content of white ceramic aggregate was decided considering the tendency of abrasion test. | |
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Table-2 Result of Marshal TestExample*1
No. | Binder content
(%) | Density
g/cm3 | Theoretical
Density
g/cm3 | Voids Content
(%) | VMA*2
(%) | VFA*3
(%) | Stability*4
(kg) | Flow Value
(1/100cm) | | 1 | 6.6 | 2.383 | 2.456 | 3.0 | 18.5 | 84.8 | 534 | 36 | | 2 | 6.2 | 2.366 | 2.438 | 3.0 | 17.5 | 82.5 | 690 | 28 | | *1 | The examples are the same with those in Table-1 | | *2 | percent Voids in Mineral Aggregates | | *3 | percent Voids Filled with Asphalt | | *4 | Stability is the value tested after 24 hours. | |
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| Abrasion Resistance and Rutting Resistance | |
Table-3 Test result of abrasion, rutting and crackingKind of
pavement | W-White
Thermo-
hardening | W-White
Modified
type II | Thin layer
concrete | Straight
asphalt
Dense Graded
top size13 | Remarks | Abrasion
resistance | Dynamic
stability
(passes/mm) | 0.47 | 0.68 | 1.95 | 4.98 | Ravelling test
-10°CA270 minAcross-chain | Rutting
resistance | Abrasion
loss
(cm2) | 42,000 | 6,650 | | 1,200 | Wheel tracking test
60°C, 6.4kgf/cm2 | | Regarding the test of Themo-Hardening type, tests were done after 10 days of curing. Regarding Thin layer concrete, the tests were done after 28 days of curing. | |
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