This document provides an overview of integrated solutions for asphalt pavement construction and maintenance techniques and equipment from Xi'an Dagang Road Machinery Co. Ltd. It discusses gravel and earth road surfacing using double bituminous surface treatment (DBST) and the equipment needed. It also covers asphalt pavement preventative maintenance techniques like seal coats and microsurfacing. Common pavement distresses like cracking and patching techniques are outlined. Rehabilitation using cold in-place recycling is described along with asphalt materials handling equipment. The company provides asphalt solutions that have been implemented in 46 countries.

1. Integrated Solutions of Asphalt Pavement
Maintenance Techniques and Equipments
西安达刚 路面机械股份 有限公司
XI’AN DAGANG ROAD MACHINERY CO. LTD.
Tel: 0086 29 88327462 E-mail: sales@xadagang.cn Website: www.xadagang.cn www.dgroadmachinery.com

2. Company Introduction
 Founded by the professors and experts from Xi’an Highway University in 1978, specialized in supplying the
integrated solutions of asphalt pavement maintenance techniques and equipments.
 Having the largest and most professional asphalt equipments research, design and manufacture base in
China.
 Drafting the industrial standard of the asphalt heating and spraying equipments in China.
The only one listed-company in asphalt heating and spraying industry in China (Stock Code: 300103).
Office building The Largest Asphalt Equipments Base in China

3. Integrated Solution of Asphalt Pavement Construction & Maintenance
Techniques and Equipments
 I. Gravel Road or Earth Road Fast and Cost-effective Surfacing and Equipments
 II. Asphalt Pavement Preventive Maintenance Techniques and Equipments
 III. Common Asphalt Pavement Distresses Treatment Techniques and Equipments
 IV. Asphalt Pavement Rehabilitation Techniques and Equipments
 V. Asphalt Materials Handling Techniques and Equipments

4. Part I.
Gravel Road or Earth Road Fast and Cost-effective
Surfacing and Equipments

5. The gravel road and earth road usually have much dust in sunny day and become
sludgy in rainy day as shown in following pictures.
In order to solve the problems mentioned above and improve all-weather traffic
capacity of the gravel and earth road with low cost and high efficiency, it is
recommend the following surfacing treatment:
 Double Bituminous Surface Treatment(DBST) or Double Chip Seal.

6.  WHAT IS DBST:
Double Bituminous Surface Treatment (DBST) is a double application of asphalt
binder in the form of an emulsion or hot spray or sometimes cutback followed by a
double application of an aggregate as close to uniform-size as possible.
Intelligent Asphalt Distributor Chip Spreader Tire Roller
DBST is better applicable to a road with medium or low-traffic volume (<4000 ADT-
Average Daily Traffic) .

7.  Main Materials:
 (Modified) Asphalt Emulsion or Asphalt Rubber (recommended)
Aggregate (Chips)
Correct Asphalt Emulsion Binder Clean and Single-size Aggregate

8.  Main Equipments:
 Computer-control Asphalt Distributor (spraying prime coat and binding coat)
 Computer-control Chip Spreader (spreading chips/aggregate)
The high-performance Computer-control Asphalt Distributor and Chip Spreader is absolutely
essential for a successful DBST, which can accurately control the spraying/spreading amount
and uniformity of asphalt binder and aggregate.

9.  Synchronous Chip Sealer (synchronously spraying asphalt binder and spreading aggregate on
one machine. It is a combination of Asphalt Distributor and Chip Spreader ).
Advantages of Synchronous Chip Sealing:
 Simultaneous spraying ensuring a perfect cohesion between the binder/chips
 The time between the spraying on the binder and the chips is constant
 This two in one machine makes it possible to use one less truck
 The reduction of the number of trucks on a work site makes it possible to divide the consumed energy by
two and thus reduce emissions of green-house gases.

10.  Strict Construction Procedures:

11. Correct equipments selected + Correct Materials + Strictly construction procedure control
= Successful Chip Seal and Great Benefits
DBST Asphalt Pavement

12.  DBST Vs. Asphalt Concrete
Equipment Cost Construction Cost Service Life Construction Period
Asphalt Concrete 100% 100% 5 to 8 years Approx. 1.5 km/day
(4cm)
DBST (around 1.5 Approx. 50% Approx. 50% 5 to 8 years Approx. 10km/day
cm)

13. Construction Case:
Double Chip Seal Project
Double Chip Seal Project
(Best combination for big chip seal
project)

14. Construction Case:
Synchronous DBST Project Synchronous DBST Project
(Australia)
(Ghana)

15. Part II.
Asphalt Pavement Preventive Maintenance
Techniques and Equipments

16. II-1: WHAT IS PREVENTIVE MAINTENANCE:
It is performed to improve or extend the functional life of a pavement. It is a strategy of surface
treatments and operations intended to retard progressive failures and reduce the need for routine
maintenance and service activities.
Trough researches to the maintenance costs and efficiency, it was indicated that doing 3-4 time of
preventive maintenance works during the service life of a pavement will prolong its service life
for 10-15 years, and 45%-50% maintenance cost will be saved.
Road Service Road Service
Performance Performance
Road Service Life Road Service Life

17. II-2: LOW-TRAFFICE-VOLUME ASPHALT PAVEMENT PREVENTIVE
MAINTENANCE
For the low-traffic-volume asphalt pavement(as shown on pictures below), it is recommended to
use the quick and low-cost seal coat for preventive maintenance.
Seal coat has the same construction procedures, materials and equipments with the double chip seal
besides the seal coat is single-layer structure and the double chip seal is a double-layer structure.

18. Seal Coat Preventive Maintenance

19. II-3: HEAVY-TRAFFIC-VOLUME ASPHALT PAVEMENT PREVENTIVE
MAINTENANCE
For the heavy-traffic-volume road (as shown on pictures below), it is recommended to use the quick
and cost-effective Micro Surfacing for preventive maintenance.

20. What is Micro-Surfacing:
Micro surfacing is a polymer-modified cold-mix paving system and begins as a mixture of dense-graded
aggregate, polymer-modified asphalt emulsion, water, mineral fillers and additives.
Micro surfacing is made and applied to existing pavements by a specialist machine-Micro Surfacing
Paver, which carries all components, mixes them on site, and spreads the mixture onto the road surface.

21. Micro Surfacing Paver

22. Re-Open to traffic within around 60 minutes.
Highway Preventive Maintenance (Project in China)

23. One lane working, one lane keeping traffic
Urban Road Preventive Maintenance (Project in India)

24. Part III.
Common Asphalt Pavement Distresses Treatment
Techniques and Equipments

25. III-1. Cracking Treatment Techniques
Fatigue cracking/ Alligator Cracking
Transverse Cracking
Treatment Techniques: Treatment Techniques:
 Localized patching Crack sealing or Crack filling
 Chip seal or seal coat Localized patching
 Mill and overlay Full-depth crack repair
Chip seal or seal coat

26. III-1. Cracking Treatment Techniques
Block Cracking Edge Cracking
Treatment Techniques: Treatment Techniques:
Crack sealing or Crack filling Crack sealing or Crack filling
Localized patching Localized patching
Chip seal or seal coat
Thin hot-mix overlay

27. III-1. Cracking Treatment Techniques
Longitudinal Cracking Slippage Cracking
Treatment Techniques: Treatment Techniques:
Crack sealing or Crack filling Localized patching
Localized patching
Full-depth crack repair

28. III-2. Surface Deformation Treatment Techniques
Rutting
Shoving and Corrugation
Treatment Techniques: Treatment Techniques:
Localized patching Localized patching
Micro Surfacing Milling and Overlay
Thin hot-mix overlay

29. III-3. Surface Defects Treatment Techniques
Bleeding Polished Aggregate
Treatment Techniques: Treatment Techniques:
 Seal coat or Double chip seal  Seal coat or Double chip seal
 Slurry seal  Slurry seal
 Micro Surfacing  Micro Surfacing
 Thin hot-mix overlay  Thin hot-mix overlay

30. III-3. Surface Defects Treatment Techniques
Treatment Techniques:
Localized patching
Fog seal
Seal coat or Double chip seal
Slurry seal
Micro Surfacing
Raveling Thin hot-mix overlay

31. III-4. Patching and Potholes Treatment Techniques
Patch Deterioration Potholes
Treatment Techniques: Treatment Techniques:
 Re-patching  Patching

32. III-5. Distresses Treatment Equipments
Cracks after filling
Crack sealing or Crack filling Equipments

33. The equipment can patch the following
distresses:
 Cracking
 Shoving and Corrugation
 Raveling
 Potholes
Patch Deterioration
Asphalt Pavement Distresses Patching Equipments

34. Cleaning
Removing the damaged
layer
Filling New Hot Mix
Asphalt Pavement Distresses Patching Jobsite Compaction

35. Rutting Repairing – Micro Surfacing Paver

36. Part IV.
Asphalt Pavement Rehabilitation
Techniques and Equipments

37. Rehabilitation is mainly applied to the pavement which has a majority of area to
occur structurally damages and it needs milling or recycling in certain depth and re-
overlay. Cold In-Place Recycling (CIR) is a perfect pavement rehabilitation
techniques for asphalt pavement that does not require heat while recycling the in-
place material. CIR can reduce the road life cycle cost by reusing the old
aggregates and asphalt materials, as well as improving road strength and grade.

38. Cold In-place Recycling

39. Cold In-place Recycler

40. Part V.
Asphalt Materials Handling
Techniques and Equipments

41. V-1. Drummed asphalt decanting and heating Techniques and Equipments

42. V-2. Hot Asphalt Transporting and Heat-preserving Techniques and Equipments
Equipped with automatic heating system and
loading/unloading system.

43. V-3. Asphalt Emulsion Technique and Equipment
An Asphalt Emulsion consists of asphalt particles dispersed in water and chemically
stabilized. Nowadays, (modified) asphalt emulsion is widely applied to the prime coat, tack
coat, chip sealing, slurry seal, micro surfacing, cold recycling, etc.
Asphalt emulsion has some obvious advantages:
Can be applied/sprayed at normal temperature.
No extra heating required.
Safety for workers
Pollution control.

44. V-4. Polymer Modified Asphalt Technique and Equipment
Increasing traffic volumes, vehicle loads , tire pressures, high and low temperature are causing
accelerated road damage. Polymer Modified Asphalt is better combating these effects and
generally considered to provide prolonged life or enhanced road performance.

45. V-5. Crumb Rubber Modified Asphalt (Asphalt Rubber) Techniques and Equipments
Asphalt-rubber is a binder used in various types of
flexible pavement construction including surface
treatments and hot mixes. According to the
ASTM definition, asphalt-rubber is “ a blend of
asphalt cement, reclaimed tire rubber, and certain
additives in which the rubber component is at
least 15 percent by weight of the total blend and
has reacted in the hot asphalt cement sufficiently
to cause swelling of the rubber particles”.

46. Main Benefits of Asphalt Rubber Paving Materials:
Extended pavement service life for 5-10 years and
lower pavement maintenance costs.
Reduced traffic noise, ranging from 3 to 8 db.
Reduced splash, spray, and hydroplaning during and
immediately after rains and thus improves safety.
Improved resistance to rutting (permanent
deformation) due to higher viscosity, softening points
and resilience.
Improved resistance to fatigue/reflection cracking due
Asphalt Rubber Mixing Unit
to higher binder contents and elasticity.
Improved resistance to aging and oxidation due to
higher binder contents, thicker binder films, and anti-
oxidants in the tire rubber.
Better chip retention in chip seals due to thick binder
films.
Savings in energy and natural resources by using
waste products.
Asphalt Rubber
Reaction Tank

47. Asphalt Rubber Chip Seal Overlay (after 8 years
use ）
Asphalt Rubber Chip Seal Overlay (after 6 years
use ）

48. The Asphalt Rubber concrete friction course not appeared
reflection cracks after 8 years use
The conventional asphalt concrete friction course
appeared reflection cracks after 8 years use

49. Traffic noise reduction

50. Reduced splash, spray, and hydroplaning during and after rains

51. Until now, our asphalt pavement techniques and equipments have
been serving in 46 countries.

52. Thanks