6 10 points If one technician in your lab uses the Gue inste

(6) (10 points) If one technician in your lab uses the Gue instead of Ga, to calculate VMA incautiously, while the values of Gab and P\'s are correct. How will this mistake affect the calculated VMA value, increase or decrease? Why? (4) (10 points) An asphalt mix with 35% reclaimed asphalt pav targeted PG of asphalt binder used in this area is PG 64-22. And the PG of RAP binder is determined as PG 88-16. Please determine the PG of virgin binder that can be used in ement (RAP) is designed, and the this RAP mixture based on the Blending Chart method.

Solution

1. SOLUTION:-

Lab technician uses G_se instead G_sb and other terms not we change.G_mb and Ps correct then affected by VMA calculation:-

Voids in the Mineral Aggregate (VMA):-

Voids in the mineral aggregate (VMA) are the air-void spaces that exist between the aggregate particles in a compacted paving mixture, including spaces filled with asphalt. VMA represents the space that is available to accommodate the asphalt and the volume of air voids necessary in the mixture. The more VMA in the dry aggregate, the more space is available for the film of asphalt. Based on the fact that the thicker the asphalt film on the aggregate particles the more durable the mix, specific minimum requirements for VMA are specified in Section 211.03 of the specifications. Minimum VMA values should be adhered to so that a durable asphalt film thickness can be achieved. Increasing the density of gradation of the aggregate to a point where below minimum VMA values are obtained leads to thin films of asphalt and a dry looking, low durability mix. Therefore, economizing in asphalt content by lowering VMA is actually counter-productive and detrimental to pavement quality.

some important terms:-

Gmb = bulk specific gravity of mix

Ps = Percent stone (100 – Pb from Ignition Method)

Gsb = bulk specific gravity of aggregates

Gse = effective specific gravity of aggregate

from the ,given formula in fig.1

VMA = 100 -( (Gmb *P_s)/Gse)

we shown as calculation VMA at a place of Gsb used Gse changes the value both value of different and VMA value are increased from the formula and relation between Gse and Gsb are :

Gsb= Gse – CF here we can say that Gse always greater than Gsb  

calculations part must we (Gmb*Ps)/Gsb must be less than

so we can say that 100-Gmb*Ps/Gse must we greater than the original value

2.SOLUTION:- not solve