Pavement density

[johnwill65]

I have some 'rule of thumb' pavemnt density number (about 147 lb/cu ft for top mix, and about 120 lb/cu ft for a base mix)but need some published source to back these up. All the DOT guides give great information on what to put in the mix, asphalt percentages, denssites 9as a percentage of the marshall number) and so forth, but need one that lists an acceptable range for pavemnt. It is for a cost estimate (for several actially) in the N Jersey area. Thank you in advance.

 

[BigH]

johnwill65: Unit weights of the bitumen will vary depending on the specific gravity of the aggregate used and the type of mix used (open or dense graded). Here on my project in West Bengal, our coarse aggregate has specific gravity of 2.95 to 3 and we use dense graded mixes. This is quite high and will not be applicable to your needs. TYour base's Rule of Thumb seems very low but you might have the numbers for a very open mix rather than a dense graded mix. The wearing course is likely dense graded and if you use dense graded base mix, it will be somewhat similar. Hopefully, there will be someone from NJ who can help you with the local aggregate and "style" of mix gradation.

 

[fndn]

Hire a local test lab and have them run Marshall's. Then multiply 90 or 93% to that number to get your actual in-place unit weights. You also could us 115 lb/sq. yards per 1" thick to get an approximate number. The best method is to core after the pavement has been constructed and measure both thickness and unit weights.

 

[BigH]

Thinking about it - I always found contractors, if they are not overly busy, a good source. As this is for a cost estimate, why not call an asphalt batch plant (supplier) and aske him??

 

[sam74]

TDOT (Tenn.) design guidelines publication lists unit weights for their various approved mixes. Here is the web link

http://www.tdot.state.tn.us/Chief_E...er_design/design/DGpdf/ENGLISH GUIDELINES.pdf

Check out Chp. 4 sections on computations.