What is the roll of anionic bitemen emulsion58%binder??

[msesi]

I'm currently carrying out double surface dressing work for dual carriageway in road construction.In the bill of quantity there is an item which require placement of curing membrane,anionic bitumen emulsion 58%binder for MC-30 and for 60/70 penetration grade.ISit necessary to use these emulsion or can be eliminated.The Contractor is requesting for the answer so that he can make an order for those emulsions.

 

[Ron]

Something seems odd about your specifications. An anionic emulsion is usually used alone to bind a surface treatment, or you can use a medium cure asphalt cement to bind the aggregate. You can modify various asphalt cements to create emulsions, but that is usually a manufacturing process, not something that is done at the project level.

The selection of either is dependent on the aggregate characteristics, weather conditions, traffic conditions, and other variables.

 

[Zambo]

are you carrying out the surface dressing on wet bound or cement bound base material?

 

[msesi]

Hi Zambo,I'm carrying out the surface dressing on primed base course composed of crushed stone base(CRR)

 

[msesi]

In addition to my previous question,Iforgot to mention the following as given in the bill of quantities:We have MC-30 Cut back bitumen and the another item we have curing membrane,anionoc bitumen emulsion 58% binder.Similarly we have an item tack coat of anionic bitumen emulsion,58%binder.Does thisitems has been placed exdentially in the bill or has its special purpose??The Contractor wants to purchase the bitumen materials now and a quick answer.Please assist.

 

[Zambo]

I cannot help, I thought maybe the emulsion was for curing a cement stabilised material road base. As you have already stated that the road base isn't CSM then this is not the purpose. As the item is in the BofQ then I think if not supplied then the contractor shouldn't be paid for that item, if this is the case I suggest you confirm the spec with the owner/client.

 

[Ryan7624]

Hi msesi,

I'm not an engineer, I'm a designer but recently i have been researching asphalt because part of my driveway is collapsing due to my next door neighbour draining half her property onto it. In my research i came across Anionic Emulsions I have attached a link which may be of some help. I realise it's probably to late but its good to know for future reference.

 

[Ryan7624]

ok obviously not allowed to post links haha

 

[Ryan7624]

For those who are worried its a virus a brief description below.

In an application of anionic emulsion, we are applying negatively charged drops of asphalt to a negatively charged surface. All components repel each other. The only way the emulsion can break is through the loss of water by evaporation. As more and more water is lost through evaporation, the particles are forced closer and closer together until they can no longer be separated by a film of water. At this point droplets coalesce into larger and larger drops and ultimately a sheet of asphalt on the road.