大粒径中温化アスコンを 使用した 滑走路補修に関する

EXAMINATION OF AIRPORT
RUNWAY REPAIRED
USING COARSE-GRADED WARM-MIX
ASPHALT MIXTURE
大粒径中温化アスコンを使用した滑走路補修に関する検討
Civil Engineering Research Institute of Hokkaido
Ryuji ABE
Hideto TAKEMOTO
Hokkaido Regional Development Bureau
Toshifumi HIRAO
Background 背景




A runway inspection in June 2000 detected a number
of circular blisters on the runway pavement
An extensive core sampling of the entire runway
found delamination of asphalt concrete layers and
severe spalling of the asphalt stabilization course
from asphalt-aggregate debonding in several places.
平成12年6月の滑走路点検時にA滑走路に舗装表面が円形状に膨れ
上がるブリスタリング現象が多数発見された。
全滑走路延長にわたり、コア採取調査を実施。層間剥離や舗装体が破
損している箇所が確認され、飛行機の安全走行上、早急に対策を行う必
要がある。
Survey purpose 調査目的
To examine causes of blistering and pavement
deterioration at New Chitose Airport
 Requirements for and methods of
improvement work



新千歳空港の舗装体の劣化原因の解明
対策工法の検討
Plan view of New Chitose Airport
新千歳空港平面図
L=3000m
Runway B
Runway B
Runway A
Runway A
Parallel Taxiway D
Parallel Taxiway D
P=4700
Items surveyed
調査項目(現地調査)
Item 調査項目
Survey purpose 調査目的
Survey on damage to sample
cores
Investigation of the section and range of
pavement failure
採取コアの破壊状況調査
Survey on water content in
sample cores
採取コアの水分量調査
Pressurized permeability test
加圧式等水量試験
Asphalt property test
アスファルトの性状試験
Marshall stability test
マーシャル安定度試験
Immersion Marshall stability
水浸マーシャル安定度試験
舗装体の破損箇所、破損範囲の把握
Investigation of water content and void
content in pavement
舗装体に含まれる水分量の把握および舗装体の空隙率の把握
Investigation of water-tightness of pavement
舗装体の水密性の把握
Investigation of asphalt failure
アスファルトの劣化状況の把握
Investigation of pavement strength
舗装体の強度の把握
Calculation of pavement equivalents
舗装体の等値換算値の算出
Maximum pavement surface temperature of
New Chitose Airport
新千歳空港の路面最高路面温度
Maximum pavement surface temperature
Month
51~55℃
56~60℃
0
0
0
0
0
0
~50℃
April
Frequency
Said day
Day
May
Frequency
6
Said day
Day
17,18,19,24,25,30
June
Frequency
4
4
Said day
Day
13,24,29,30
16,17,18,21
July
Frequency
5
3
1
Said day
Day
6,7,16,24,25
2,11,14
10
August
Frequency
7
2
1
Said day
Day
8,9,12,13,14,19,21
18,24
17
Total
Frequency
22
9
2
Waterless core (P=4700)
無水コアの状況(P=4700)
Survey section No. 3Runway AObservation point SP=4700
Layer thickness
Douroscope
Formation
コア内部状況
構成
層厚(m)
Overlay
オーバーレイ
Dense-graded
asphalt mixture
0.058
0.06
0.047
旧表層
Coarse-graded
asphalt mixture
基層
10m from CL on the R side
Depth
Sample core
採取コア
深度(m)
0.11
0.050
0.16
0.065
0.22
Asphalt
stabilization
アスファルト安定処理
0.095
0.32
Asphalt
stabilization
アスファルト安定処理
0.093
0.41
Damage to each runway layer
(right side of Runway A)
5
1st layer
2nd layer
4
3rd layer
3
4th layer
5th layer
2
6th layer
1
Total
6th
4800
4600
4400
4200
4000
3800
3600
3400
3200
Observation point
3000
2800
2600
2400
2200
2000
1800
0
Nunber of collapses and cracks
6
各層の破損状況(R側)
1st
laye
r
laye
r
Water content in Runway A (P = 4700)
A滑走路の含水比(P=4700)
Construction joints
Construction joints
2.5
Upper binder course
(coarse-graded asphalt mixture)
Lower binder course
(coarse-graded asphalt mixture)
2
Water content(%)
Construction joints
1.5
1
0.5
0
0
5
10
15
20
Distance from center (m)
25
30
Void content in Runway A (P=4700)
A滑走路の空隙率(P=4700)
Void content (%)
Construction
joints
10.00
Construction joints
Construction joints
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
Overlay layer
Surface course
0
5
10
15
20
Distance from center
25
30
Pressurized permeability test
加圧透水試験
Observation point
Name of mixture
P=3200
P=3400
P=4000
P=4100
1.43×10-5
Impermeable
water
4.43×10-4
Impermeable Impermeable
water
water
1.66×10-4
1st layer
Overlay
オーバーレイ層
Impermeable
water
2nd layer
Dense-graded asphalt mixture
旧表層
1.74×10-7
3rd layer
Coarse-graded asphalt mixture
基層(上部)
6.89×10-4
th
4 layer
Coarse-graded asphalt mixture Impermeable
基層(下部)
water
4.88×10-4
1.70×10
-3
1.52×10-5
4.12×10
-5
5.10×10-5
1.79×10
-4
5th layer
Asphalt stabilization
アスファルト安定処理(上部)
9.13×10-4
9.55×10-4
Impermeable
water
4.33×10-4
6th layer
Asphalt stabilization
アスファルト安定処理(下部)
1.06×10-3
3.36×10-3
4.34×10-4
2.04×10-3
Unit:cm/sec
Pavement damages and their causes
損傷原因の推定図
Requirements for and methods of improvement work
改良工法の検討










Requirement and Improvement method:
The repair work of Runway A should be was carried out under normal
operation of the runway.
Hours of repair work should be from 23:00 to 6:00 the next morning, i.e.,
when the runway is closed.
The thick-lift method was employed for asphalt placement after the
removal of the existing asphalt stabilization course, which had severe
spalling. The method facilitates a thicker placement thickness of asphalt
per spreading than conventional methods and thus reduces the time
required for installation.
To enable rapid re-trafficking, warm-mix asphalt mixture that can be placed
at temperatures 30 to 50℃ lower than hot-mix asphalt mixture was
employed
運用・工法に関する条件
①A滑走路は工事期間中、空港閉鎖は行わない。
②施工時間は23:00~6:00まで
③砂利状化している既設安定処理層撤去後の復旧は、施工時間短縮からシックリフト工法
(大粒径アスファルト混合物)を検討
④交通開放までの冷却時間の短縮から30~50℃温度低下が可能な中温化混合物の検討
Pavement recovery process at New Chitose Airport
新千歳空港の作業工程
st
1 stage
60.0m
20.0
10.0 10.0
20.0
第一工程
Zonal cutting (t=42cm)
帯状切削
L10
C
L
R10
3.8 6.2 3.8 6.2 3.8
60.0m
20.0
10.0 10.0
20.0
Temporary surface course (t=16cm)
上層路盤
L10
C
L
R10
3.8 6.2 3.8 6.2 3.8
20.0
60.0m
10.0 10.0
20.0
Base course (t=26cm)
暫定表層
L10
C
L
R10
3.8 6.2 3.8 6.2 3.8
Test pavements 試験施工

大粒径中温化アスファルト混合物の適用性の検討
Items surveyed in the test construction
Items surveyed 調査項目
Survey purpose 調査目的
Combination of construction machines/ Selection of construction machines/Investigation
frequency of rolling compaction
of core density at the site
施工機械の組み合わせ・転圧回数
転圧機械の構成、現場密度の把握
Measurement of mixture temperature
混合物の温度測定
Investigation of decrease in temperature of
coarse-graded warm mixed asphalt mixture
Evenness test
Investigation of evenness
平坦性試験
平坦性の把握
Driving test
Investigation of initial rutting
走行試験
初期わだちの把握
Stationary steering test
Investigation of stationary steering resistance
すえ切り試験
すえ切り抵抗の把握
中温化混合物の温度低下状況の把握
Measurement of texture depth using the
Measurement of pavement surface texture depth
sand patching method
舗装路面のきめ深さの把握
サンドパッチング法によるきめ深さ測定
Vehicle-traveling test 走行試験





Conclusion
Causes of pavement deterioration
まとめ
1) Water intruding from structurally weakened construction joints
was trapped in the pavement body and between layers.
2) Watertight mixture was applied to pavement as overlay,
producing impermeable sections.
3) Water trapped between layers and under construction joints
evaporated from solar heat as the atmospheric temperature rose,
which generated vapor that blistered the pavement body.
4) An asphalt stabilization course with high void content and
water-holding capacity retained water. Asphalt deterioration
induced by water erosion and freeze-thaw resulted in aggregateasphalt debonding.
ブリスタリング現象の発生原因
①舗装構造上の弱点である施工継目から浸透した水が舗装体に滞水し、舗装体や層間に水分が含
まれるようになった。
②オーバーレイ工事により水密性の高い混合物が舗設され、不透水になった箇所が生じた。
③外気温が高い時期に層間や施工継目に含まれた水分が日射により気化し、蒸気となって舗装体
を持ち上げるブリスタリング現象が生じた。
④空隙率が高く保水能力の高いアスファルト安定処理層に滞水し、水による劣化や凍結融解によっ
てアスファルトが劣化し、骨材が剥離する状態になった。

Conclusion




まとめ
Test construction result
Through the application of coarse-graded warm-mix asphalt
mixture to 42-cm-thick pavement, it was verified that lowtemperature installation and proper temperature control of
mixture achieves the required durability/stability, as seen in the
flow resistance and resistance to aggregate-asphalt debonding
on the surface.
試験施工の結果
舗装厚42cmの大粒径混合物は充分な温度管理を行うことに
より、耐流動性や骨材飛散抵抗などの早期供用性に必要な
耐久性を確保することが可能である。
Postscript
おわりに

Follow-up research will be organized to
investigate the mechanism of pavement
deterioration and to examine the applicability
of remedial measures.

損傷原因のメカニズムや対策工法の有効性の検証