西安达刚路面机械股份有限公司XI’AN DAGANG ROAD MACHINERY CO. LTD.

Integrated Solutions of Asphalt Pavement Maintenance Techniques and Equipments

Tel: 0086 29 88327462 E-mail: sales@xadagang.cn Website: www.xadagang.cn www.dgroadmachinery.com

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 buildingOffice building The Largest Asphalt Equipments Base in ChinaThe Largest Asphalt Equipments Base in China

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

Integrated Solution of Asphalt Pavement Construction & Maintenance Techniques and Equipments

Part I.

Gravel Road or Earth Road Fast and Cost-effective Surfacing and Equipments

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.

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.

DBST is better applicable to a road with medium or low-traffic volume (<4000 ADT-Average Daily Traffic) .

Intelligent Asphalt Distributor Chip Spreader Tire Roller

Main Materials:

(Modified) Asphalt Emulsion or Asphalt Rubber (recommended)Aggregate (Chips)

Correct Asphalt Emulsion Binder Clean and Single-size Aggregate

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.

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.

Strict Construction Procedures:

Correct equipments selected + Correct Materials + Strictly construction procedure control = Successful Chip Seal and Great Benefits

DBST Asphalt Pavement

DBST Vs. Asphalt Concrete

Equipment Cost Construction Cost Service Life Construction Period

Asphalt Concrete(4cm)

100% 100% 5 to 8 years Approx. 1.5 km/day

DBST (around 1.5 cm)

Approx. 50% Approx. 50% 5 to 8 years Approx. 10km/day

Double Chip Seal Project

Construction Case:

Double Chip Seal Project(Best combination for big chip seal

project)

Synchronous DBST Project

(Australia)Synchronous DBST Project

(Ghana)

Construction Case:

Part II.

Asphalt Pavement Preventive Maintenance Techniques and Equipments

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 Performance

Road Service Life

Road Service Performance

Road Service Life

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.

Seal Coat Preventive Maintenance

II-3: HEAVY-TRAFFIC-VOLUME ASPHALT PAVEMENT PREVENTIVE MAINTENANCEFor 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.

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.

Micro Surfacing Paver

Highway Preventive Maintenance (Project in China)

Re-Open to traffic within around 60 minutes.

Urban Road Preventive Maintenance (Project in India)

One lane working, one lane keeping traffic

Part III.

Common Asphalt Pavement Distresses Treatment Techniques and Equipments

III-1. Cracking Treatment Techniques

Fatigue cracking/ Alligator CrackingFatigue cracking/ Alligator Cracking

Treatment Techniques: Localized patching Chip seal or seal coat Mill and overlay

Transverse CrackingTransverse Cracking

Treatment Techniques:Crack sealing or Crack fillingLocalized patchingFull-depth crack repairChip seal or seal coat

III-1. Cracking Treatment Techniques

Block CrackingBlock Cracking

Treatment Techniques:Crack sealing or Crack fillingLocalized patchingChip seal or seal coat Thin hot-mix overlay

Edge CrackingEdge Cracking

Treatment Techniques:Crack sealing or Crack fillingLocalized patching

III-1. Cracking Treatment Techniques

Longitudinal CrackingLongitudinal Cracking

Treatment Techniques:Crack sealing or Crack fillingLocalized patchingFull-depth crack repair

Slippage CrackingSlippage Cracking

Treatment Techniques:Localized patching

III-2. Surface Deformation Treatment Techniques

RuttingRutting

Treatment Techniques:Localized patching Micro SurfacingThin hot-mix overlay

Shoving and CorrugationShoving and Corrugation

Treatment Techniques:Localized patchingMilling and Overlay

III-3. Surface Defects Treatment Techniques

BleedingBleeding

Treatment Techniques: Seal coat or Double chip seal Slurry seal Micro Surfacing Thin hot-mix overlay

Polished AggregatePolished Aggregate

Treatment Techniques: Seal coat or Double chip seal Slurry seal Micro Surfacing Thin hot-mix overlay

III-3. Surface Defects Treatment Techniques

Treatment Techniques:

Localized patchingFog sealSeal coat or Double chip sealSlurry sealMicro SurfacingThin hot-mix overlay RavelingRaveling

III-4. Patching and Potholes Treatment Techniques

Patch DeteriorationPatch Deterioration

Treatment Techniques:

Re-patching

PotholesPotholes

Treatment Techniques:

Patching

III-5. Distresses Treatment Equipments

Crack sealing or Crack filling Equipments

Cracks after filling

Asphalt Pavement Distresses Patching Equipments

The equipment can patch the following distresses: Cracking Shoving and Corrugation Raveling PotholesPatch Deterioration

Asphalt Pavement Distresses Patching Jobsite

Removing the damaged layer

Cleaning

Filling New Hot Mix

Compaction

Rutting Repairing – Micro Surfacing Paver

Part IV.

Asphalt Pavement Rehabilitation Techniques and Equipments

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.

Cold In-place Recycling

Cold In-place Recycler

Part V.

Asphalt Materials Handling

Techniques and Equipments

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

V-2. Hot Asphalt Transporting and Heat-preserving Techniques and Equipments

Equipped with automatic heating system and loading/unloading system.

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 workersPollution control.

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.

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”.

Asphalt Rubber Mixing Unit

Asphalt Rubber Reaction Tank

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 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 Chip Seal Overlay (after 6 years usAsphalt Rubber Chip Seal Overlay (after 6 years usee））

Asphalt Rubber Chip Seal Overlay (after 8 years usAsphalt Rubber Chip Seal Overlay (after 8 years usee））

The Asphalt Rubber concrete friction course not appeared The Asphalt Rubber concrete friction course not appeared reflection cracks after 8 years use reflection cracks after 8 years use

The conventional asphalt concrete friction course The conventional asphalt concrete friction course appeared reflection cracks after 8 years useappeared reflection cracks after 8 years use

Traffic noise reductionTraffic noise reduction

Reduced splash, spray, and hydroplaning during and after rainsReduced splash, spray, and hydroplaning during and after rains

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

Thanks