Commonwealth of Pennsylvania PA Test Method No. 6 Department of Transportation October Pages LABORATORY TESTING SECTION. Method of Test for

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1 Commowealth of Pesylvaia PA Test Method No. 6 Departmet of Trasportatio 7 Pages LABORATORY TESTING SECTION Method of Test for DETERMINATION OF PERCENT WITHIN LIMITS (PWL) FOR CONSTRUCTION AGGREGATE 1. SCOPE 1.1 For determiatio of Costructio Percet Withi Limits (PWL) usig Statistical Method as i CAMMS.. DEFINITION OF A MAJOR/MINOR DEVIATION.1 Major Deviatio - Whe a sample PWL is less tha 90%.. Mior Deviatio - Whe a sample PWL is greater tha 90%, but less tha 100%. 3. GENERAL STATEMENTS ABOUT PWL CALCULATIONS 3.1 If all results o a particular sieve or wash test are withi the specificatio limits, the the costructio PWL for that result is If oe or more results of three are outside the specificatio rage for a particular sieve the statistical PWL o the report is used to calculate the total sample PWL based o costructio specificatios. 3.3 O specificatio sieves that have a upper limit of 100, Q U is ot calculated. Q L is the oly value calculated ad used to represet the PWL for that sieve. 3.4 O specificatio sieves that have a lower limit of 0, Q L is ot calculated. Q U is the oly value calculated ad used to represet the PWL for that sieve. 3.5 O specificatio sieves that have both limits as 100, oly use the upper limit ad calculate oly the upper Quality Idex to represet the PWL for that sieve. 4. CALCULATIONS Note: The followig calculatios are from the #4 sieve o the CAMMS report o page The lot (X) measuremets are averaged to fid X. Xi X = i=1

2 Page X = Average or mea value of the umber of tests to the earest whole umber X i = Size of the sample i whole umber icremets = The ith value i a series of observatios i whole umbers Example: Calculatios for the #4 sieve for 3 test results (See a example of a test report o page 5) X = = = 7.7 = The stadard deviatio "s" of the sample icremets for each sieve is calculated usig whole umbers. The calculated value is to the earest teth. s = i=1 (Xi - -1 X ) X = Average or mea value of the umber of tests to the earest whole umber X i s = Size of sample i whole umber icremets = The ith value i a series of observatios i whole umbers = The Stadard Deviatio of the lot of measuremets Example: With the X calculated to be 8, s would be calculated. (8-8 ) +( - 8 ) +(33-8 ) 61 s = = = 5.5=

3 Page The Quality Idex (Q U ) is foud by subtractig the average ( X ) of the measuremets from the upper specificatio limits (U) ad dividig the result by "s" ad is expressed to the earest te thousadth. = Q U (U - X ) s X = Average or mea value of the umber of tests s = The Stadard Deviatio of the lot of measuremets U = Upper Specificatio Limit Q U = Quality Idex of the upper specificatio limit P U = Estimate of the percetage of a lot which has values equal to or less tha the upper specificatio limit Example: With the upper specificatio limit equal to 50, Q u would be calculated QU = = = PU = NOTE - P U was foud i Table A of Publicatio 408, Sectio 106 for = The Quality Idex (Q L ) is foud by subtractig the lower specificatio limit (L) from the average (X) ad dividig the result by "s". This value is expressed to the earest te thousadth. ( = Q L X - L) s L = Lower Specificatio Limit X = Average or mea value of the umber of tests s = The Stadard Deviatio of the lot of measuremets Q L = Quality Idex of the lower specificatio limit P L = Estimate of the percetage of a lot which has values equal to or greater tha the lower specificatio limit

4 Page 4 Example: With the lower specificatio equal to 4, Q L is calculated QL = = = 0.77 PL = NOTE: P L was foud i Table A of Publicatio 408, Sectio 106 for = The percetage of material that will fall withi the upper tolerace limit (U) is estimated by eterig Table A i Publicatio 408 Sectio 106, with Q u, usig the colum appropriate to the total umber of measuremets (). 4.6 The percetage of material that will fall withi the lower tolerace limit (L) is estimated by eterig Table A i Publicatio 408 Sectio 106 with Q L, usig the colum appropriate to the total umber of measuremets (). 4.7 I cases where both upper (U) ad lower (L) tolerace limits are cosidered, the percetage of material that will fall withi tolerace limits is foud by addig the percet (P U ) withi the upper tolerace limit (U) to the percet (P L ) withi the lower tolerace limit (L) ad subtractig 100 from the sum. Example: Percet withi limits = (P U + P L ) Percet withi limits = ( ) = 7 Below is a example of how idividual PWL's are calculated to determie the costructio aggregate specificatio PWL o a CAMMS report. (See the CAMMS report o page 5.) Sieve Size Statistical PWL o Report Iteral Costructio PWL Calculatios " /4" /8" # # Wash Test /6 results=83.5=84

5 Page 5 Note - If all the test results o the #4 sieve were withi the specificatio limits, it is possible that the statistical PWL o the report will be below 100%. If all the test results for the #4 sieve are withi the specificatio limits, the costructio PWL calculatios will be 100%. 4.8 To determie the percetage withi tolerace whe the calculated Quality Idex (Q.I.) value is betwee two tabular values i Table A, the followig procedure is used The differece betwee the tabular Q.I. values o either side of the calculated Q.I. value will be determied The differece will be divided by ad the quotiet added to the lower tabular Q.I. value, resultig i the iterpolated Q.I. value If the calculated Q.I. is equal to or greater tha the iterpolated value, the higher listed percet withi tolerace will be used If the calculated Q.I. is less tha the iterpolated value, the lower listed percet withi tolerace will be used. Note - Whe percet loss by wash is required, the (X) ad ( X ) calculatios are rouded to the earest hudredth. The stadard deviatio(s) is rouded to the earest teth.

6 Page 6 REPORT: CA~LR510 AGGREGATE 13:0:59 FINAL REPORT Ref#: Lab#: Pass/Fail: F CAMSPROD Cot #: QA Rtug: MAJOR Ctrctr: Pr O #: Orgzt: Lct Cd: Mtl Ds: AGGRGT,COARSE Sectio: L/C XRf: 408Y/S: Statio: Prt Tkt: Supl #: Colcted: Lot Nbr: Plc Cl: Receivd: # Icrm: 3 Smp By: Releasd: 447 XRf: TR-447 Remarks: SUBBASE SCREEN LIMITS R(L) AVG ST DEV R(S) PWL 1/ /" /4" /8" # # # N # # # # LIMITS R(L) AVG ST DEV R(S) PWL PERCENT LOSS BY WASH TOTAL SAMPLE PWL BASED ON CONSTRUCTION SPECIEICATIONS: 84 J

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