The program will take place Sunday, June 7 to Friday, June Subject matter ranges from fundamentals to advanced and sophisticated concepts. The Institute places special emphasis on contemporary concepts, processes and strategies. The institute is designed to supplement engineering expertise with leadership and management techniques oriented to highway and transportation department operations.
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Sieves-With square openings ofthe following sizes conforming to M 92, for sieving the samples in accordance with Seetions 5, 6, and 8: 4. I8mm No. Containers for Samples-Sieves Used, out-of-tolerance sieves according to M 92, in acceptable condition, may be used as containers Note 1. Coarse Aggregate Fine AggregateO-l1m No.
Note 1-Sieves Substitution with such containers may affeet results. Referee testing, comparison testing, or testing of aggregate to be used in critical applications must be performed using sieves Apparatusfor lmmersing Samples in Solurion optional -When neeessary, apparatus for holding the sieves containing the sample for irnmersing into the solution shall be constructed in such a manner to permit free access of the solution 10the sample and drainage of the solution from the sample.
Temperature Regulation-Suitable means for regulating the temperature ofthe samples during irnmersion in the sodium sulfate or magnesium sulfate solution shall be provided.
Thennometer-A thermometer covering the recornmended temperature range for solutions during test and readable to O. Temperature Recorder-A unit capable of reeording solution temperature a mnimum of once every 10 minutes for the duration ofthe test with an accuracy ofO. Balance-The balance shall have sufficient capacity, be readable to 0. TS-1c T Drying Oven-The oyen shall be capable ofbelng hcatcd continuously at "C ""F and the rate of evaporation, at this range of temperature, shall be at least 25 gIh for 4 hours, during which period the donrs of the oyen shall be kept closcd.
This rate shall be determincd by the loss of water from I-liter Griffin low-form bcakers, cach lnitially containing g of water at a temperaturc ofl: 2"C 70""F , placcd at cach comer and the center of cach shclf ofthe oyen. The evaporation rcquirement is lo apply lo aIJ test locations when the oyen Is empty exccpt for the bcakers of water. SpeciJic Gravity Measurement-Hydrometcrs conforming to the requirements of ASTM E l00,or a suitable combination of graduatcd glassware and balance, capable of mcasuring the solution specific gravity within Prepare the solution for immersion of test samples from either sodium or magnesium sulfate in accordance with Section 4.
The volume ofthe solution shall be at least five times the solid volume of all samples immerscd at any one time. Note 2-Some aggregates containing carbonates of calcium or magnesium are attackcd chemically by frcsh sulfate solution, resulting in erroneously high-measured losses. Sodium Sulfate Solution-Prcpare a saturatcd solution of sodium sulfate by dissolving a rcagent grade of the salt in water Note 5 at a temperature of 25C 77"F minimum.
Add sufficient salt Note 3 of the anhydrous Na2SO. Thoroughly stir the mixturc during the addition of the salt and stir the solution at frequent interVals until used. To reduce evaporation and prevent contamination, keep the solution covcred at aIl times when access is not needed. AIJow the soJution to conl lo Again stir, and aIlow the solution lo remain at the designatcd temperaturc for at least 48 hours before use.
Prior to each use, break up the salt cake, if any, in the container, stir the solution thoroughly, and determine the specific gravity of the solution. When uscd, the solution shall have a specific gravity not less than 1. Discard a discolored solution, or filter it and check for specific gravity. However, since this salt is not completcly stable and since it is desirable that an excess of crystals be present, the use of not less than g of!
Magnesium Sulfate Solution-Prepare a saturated solution of magnesium sulfate by dissolving a rcagent grade of the salt in water Note 5 at a minimum temperature of 25C 77"F Note 4. Add sufficlent salt Note 4 of either the anhydrous MgSO. Thoroughly stir the mixturc during the addition of the salt and stir the solution at frequent interValsuntil used. To reduce evaporation and prevent contamination, keep the solution covered at aIl times when access Is not needed.
AIlow the solution 10conl lo Again stir, and allow the soJution to remain at the designatcd temperaturc for at least 48 hours before use. Prior to cach use, break up the salt cake, if any, in the container, stir the solution thoroughly, and determine the specific gravity ofthe solution.
When used, the solution shall have a specific gravity not less than 1. However, since Ibese salts are nol complelely stable, wilb Ibe hydrous sall being Ibe more stable of Ibe Iwo, and since il is desirable Ihal an excess of crystals be presenl, il is recommended Ibal Ibe heptahydrate sall be used and in an amounl of nol less Iban gIL of water.
When preparing Ibe saluraled solulion of magnesium sulfate, Ibe sall crystals will dissolve more readily if Ibe crystals are added in small amounts and Ihe water lemperature is higher Iban 3SoC 9SF due lOIbe chemical cooling effecl during preparalion. Note 5-Distilled water shall be used in referee or comparison tesling.
Fine Aggregate-Fine aggregale for Ibe test shall be passed through a 9. The sample shall be of such size Ihat il will yield nOlless Ihan g of each of Ibe following sizes, expressed in terms of Ihe following sieves: Passing Sieve Retained on Sieve 9.
Should Ibe sample contain less Iban five percenl of any ofthe sizes specified in Section S. I, Ibal size shall nol be lesled. The sample shall be of such a size Ibal it will yield Ibe amounts indicaled in Table 1. Table 1-Coarse Aggregale Sample nun ro S-rnm 10 O-mm to 9. S-mm to 9. When a combination of sires is specitied for!
When testing large rock broken stone, Jedge rock, cobbles, and boulders for use as riprap, channel lining, etc. Test only! Test pieces in! Note 6-When! Sawing will usually leave! When testing large rock to evaluate a polential source which will be subsequently crushed 10 produce aggregate, obtain the test portion by crushing!
Test pieces only in! Discard material tiner than 4. When an aggregate to be tested contains appreciable amounts of bo! C ":t 9"F , and separate into! In general, a 1l0-g sample will be sufticient. Do not use tine aggregate sticking in! Weigh samples consisting of IOO:t 0. Coarse Aggregate-Thoroughly wash and dry the sample of coarse aggregale to constant mass at ":t S. C ":t 9"F and separate it into! Weigh out quantities of! In the case of sires larger Iban Note 7- The fractional components of each sample may be placed in separate containers if so desired but is not required.
Percent Test. IBmmtopm 2S 4. S mm 20 4. Sec Scction Note 8. Cover the containers to reduce evaporation and prevent! The temperature of! Establish the time required to attain constant mass as follows: wi! Constant mass will be considered to have been achieved when mass loss is less than 0. After constant mass has been achieved, allow the samples to cool to 20 to 25C 68 to 77F Note 10 , when they shall again be immersed in the prepared solution as described in Section 7.
Cooling may be aided by the use of an air conditioner or fan. Temperature of! Note Drying time required to reach constant mass may vary considerably for several reasons.
Efficiency of drying will be reduced as cycles accumulate because of salt adhering to particles and, in some cases. The different size fractions of aggregate will have differing drying rates. The smaller sizes will tend to dry more slowly because of their larger surface area and restricted interparticle voids, but tbis tendency may be allered by tbe effects of container size and shape. Note Experience has shown tbat sample temperatures significantly different tban tbe solution temperature of Number 01Cycles-Repeat tbe process of altemate immersion and drying until tbe required number of cycles is obtained.
Review tbe temperature record from tbe recording unit. Verify solution temperature limits were not exceeded.
Make tbe quantitative examination as follows: 8. After tbe completion of tbe final cycle and after tbe sample has cooled. Wash by circulating water at t: 6e l10":t: IO"F through the samples in tbeir containers by introducing hot water near the bottom and allowing tbe water to pass through the samples and overflow.
The tboroughness of washing shall be checked by obtaining a sample of rinse water after it has passed through tbe samples and checked with 0. Further washing is required if sample becomes cIoudy upon addition of the barium chloride solution. In areas where the water gives a reaction witb barium chloride otber analytical means shall be used to assure thoroughness of washing.
In tbe washing operation. After tbe sodium sulfate or magnesium sulfate has been removed.
AASHTO T 104
Kecage Aashto tusing magnesium sulfate solution, abrasion and impact testing, aashto t 96 c 1. Csibridge manual on how the program run per aashto lrfd In north carolina, i40 enters the state along the pigeon river aashtto, from tennessee. The need for uniform standards was recognized long ago. Aashto t testing services soundness of aggregate.