Capping Layer
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Thank you for these important infomation .
i have stated what we have in our specification and standards.
i will try to investigate the subject more and i will come back if if successe to gather any additional infomation.
May be but we are following BS standareds and i believe that the capping layer terminology should not be varied and from the name of this layer as capping mean the top layer or the end layer and it should not be between the layers.
Tack coat is:
emulsified asphalt diluted with an equal quantity of water (1:1).
it shall be applied to a previously laid asphalt layers ( base course or binder course).
the rate of application is 0.3 liters to o.6 liters per square meter.
the application tempreture for the tack coat shall be between 10 deg. c and 60 deg. c
after application the surface shall be allowed to be dried (fo 2 hours approx.).
Capping layer is :-
aggregate sub-base materials mixed with 4% cement and the thick of this layer can be 150 0r 200 mm .
it should be laid on the vere after the completion of all asphalt layers on the carriage way and shoulders in order to protect the verge and to act as stabilizing layer .
so the predessor for this activity is completion of asphalt weaing couse and comletion of the verge construction.
May be they have only mech eng in their Company.
Can u do planning for ShutDown Plant being Civil Planner (if you are really ) I donot think so........
May be they have only mech eng in their Company.
Can u do planning for ShutDown Plant being Civil Planner (if you are really ) I donot think so........
Hi Stuart,
Thank you so much for the answer,thank you, it is really a big help
Regards
Rick,
In basic terms, in road construction a capping layer is a depth of generally oversized hardcore required beneath the sub base when ground condition testing has determined the CBR is too low. The CBR is the California Bearing ratio and scales the compactibility of the existing ground.
A capping layer will be approx 200mm in depth and will be compacted in 50-100mmlayers using a twin drum seated roller.
The capping layer is the lowest level of the road construction. the sub base will be approx 150-200mm followed by binder course of 20mm dense bitumen macadam followed by 40-60mm of 10mm surface course.
I took this next bit froma manual extract, hope it helps:
"for subgrades the CBR less than 15%, the manual states that the maximum thickness of aggregate layer (capping or sub-base) shall be 150mm, and for a subgrade of CBR less than 3%, the first layer of aggregate placed (as capping or sub-base) shall be at least 200mm thick. Possible measures to be taken for cases where the subgrade is particularly soft (CBR less than 2%) are also given in the manual."
Well hopefully that helps,
Stuart Johnson
Hi Mr. Chan,
Thank you for the advice, unfortunately, i have no resources at this moment, actually what i am doing right now is an advance scheduling, our skilled people will be coming by next month from different country, although it is already in my plan to ask them , i just took an opportunity to ask all of you guyz, maybe someone out there would give at least an exact answer to my question.
Cheers.
You will be far better off to ask your subbies and foremen. They will be the people who will be actually doing that and whose knowledge you require to understand the process that you then model electronically.
By being nice to them, they may even go on to do the planning for you. After all, if you are planning for them, shouldnt you know the details from them to do that planning?
Let them talk, and listen to them and encourage them. They will tell you and may sketch for you the schematics of the work that you can then pop into the computer that you can claim all for your own.