Downloaded from https://www.everyspec.com MPmD-4aaA Jaluwy 1- Charge the hented aggrvgate into the mix- ing tmv!, nnd mix the dry aggregate ~horoughly. Form R crater in the dry Mended aggregate. ml G dd the required weight of bitumen ~t the required tem- ]It-mture. Mix the nggmefmte and bituminous m~teria] rapidly unti I the G ggregate is Ihorough)y coated. the specimen are used for mix designs for facilities that will be used by G ircraft with tire preamma greater than IQ psi. After compaction, mrnove the ke plsta and im- merse the mold contnin{ng the specimen in cmd w~ter for Iwt less than .2 minutes.
Remove specimen from mo)d by meana of the sample extractor and a suitable jack and frame G rrangement. Since rubberiaed- t~r sp~imerm stick tightly in the mold, place them in 120° F. bath for a few sec- onds to release them from the wall of the mold. After removal from the mold, care- fuHy transfer the specimen t~ a smooth, fla1 surface. 3.3 compaction of specimens Thoroughly rle~n the specimen mo!ri assembly G nd the face of the cornrmction hammer, and heat them either in hot \“:ater or on n hotplnte IO a ter.]perature Mween 180” and 2S0° F. Plr.cc a !>iece of filier paper or PWr tuvcling cut to size in the bottom of the moi{i &fore the Imixture is intrdud.
I’!are the mixture :in the moid, nnd Rp*df. with n heated spatula or truwel twice ~round the perimeter. Remove the col!~~) 4. Test procedure. ! ;.1 Density determination. Weigh the specimen in air nnd in water that is clem nmt is nt a tempe:aiure of approximately 77° F. The diITrrence between the two \vcights in grams gives the volume in cubic cen; im~ters, The density (or specific gravi - iy) of the qmcimen is determined by divid- ing the weigh: of the specimen in grams b}- the vo!un-,e in cubic centime!crs, which ran be converted into pounds per cubic foot b> mu]ti@yj~ by 62.4. ()~n-textured or - !>orous specimens will absorb vmter, giving nn e~”roneouBresult when weighed in u-ater.
Therefore, it is reccmmmied (hat the speci- ~Ien be reweighed in air di~)y nfter v,-eighing in Irater and wr~tion ,madc for absorbed water (fig. 100-!3). For ex- tremely p~rous specimens, it is lWom- mende(i that the specimen be coated with p~raffin to ~ea~ a]] void openings and ~hen ivcighed in air and water (fig. 100-9). Correction shall be made for weight and volume of the paraffh. Fig. 100-10 is the form recomrnendt+ for recording density };nd other required dnta. and smooth the surfnc? of the mix with R trowel to a aiightlv rounded shape. Tem- !wr~tures of the mixtures immedjateIy prior Io compaction :.hall .A II!ltit Celllcllt . .. .. .... 260 = ~ .. .. T:IY, RT-10, -11, -12 Ieo=s ]:
u~tkyi~e~ tfi] . ,. ... ........--.. ~=s Replace the colhw, place the mold aseemb~ o]? the compction pedestnl in the mo]d holder, and ~pply 50 or 75 blows, with the compaction hammer with a free fall of 18 in. Remove the baee plate and coIlnr, and reverse and reassemble the mold. Apply the snme number of compaction blows to the fwe of the reversed nptcimen. Fifty Mows on each nirie of the specimen nr~ used for mix design for roadm, ntreetn, and facilities for aircrnft with tim Mated to 100 psi or lem; 76 blows on each elde of .1.2 Determination of maximum load and IIow. Bring the specimen to the test tem- perature indicated in the fol)owing tabuls- .-