904.1DESCRIPTION QUALITY LEVEL ANALYSIS (QLA)
The Department will analyze lot test results collectively and statistically using the Quality Level Analysis method. Quality Level Analysis is a statistical procedure for estimating the percent compliance with a specif ication; it is affected by shif ts in the arithmetic mean, and by the sample standard deviations. The Department will use this a nalysis to estimate the total percent of the lot that is within specification limits. The ma ximum pay factor per lot is one (1.0).
If the Department’s Assurance testing validates the Contractor ’s Quality Control testing, then the Department will use both sets for pay factor determination. Use of the Contractor’s test results is dependent on the following conditions:
“Quality Control.”
results using the F-test and T-test , conducted at a level of s ignificance of 0.01.
as detailed in the Quality Control plan per Section 902, “Quali ty Control Plan.” The Contractor shall not include informational test data obtained b y test results beyond the Contractor’s random sampling plan locations. If a split sa mple is taken to determine deviations between Contractor and Department process, only data obtained from a random sampling plan location can be utilized i n the Quality Level Analysis. If a split sample is tested by the Contractor and De partment for informational purposes and the lo cation does not represent either the Contractor’s or Department’s random sampling plan locations, neither test da ta results are to be included in the Quality Level Analysis.
If the Department cannot validate the Contractor’s test data a t any time during the Project; the Project Manager and Quality Control technician wil l investigate to determine why and make corrections if possible. If the discrepancy cannot be resolved, then, unless otherwise approved by the Assistant District Engineer for Const ruction, the Department will determine the pay factor using the Department’s test values onl y for characteristics that do not validate. Characteristics that do validate will use both Contr actors and Departments data to determine pay factors.
The Contractor shall use the following steps to calculate the standard deviation:
nxx (Equation 1) Where, x is the arithmetic mean is the summation of x is the individual test value n is the number of test values
Section 904: Quality Level Analysis (QLA) Page 935 12 nxxs (Equation 2) Where, s is the sample standard deviation is the summation of x is the individual test value x is the arithmetic mean n is the number of test values
sx USLQU (Equation 3) Where, UQ is the upper quality index USL is the upper specification limi t, or TV plus allowable deviati on above TV x is the arithmetic mean s is the sample standard deviation TV is the Target Value
sLSLxQL (Equation 4) Where, LQ is the lower quality index x is the arithmetic mean LSL is the lower specification lim it or TV minus allowable deviati on below TV s is the sample standard deviation
which corresponds to a given Q U) from Table 901.7:1, “Quality Level Analysis by the Standard Deviation Method Upper Quality Index QU or Lowe r Quality Index QL.” If a USL is not specified, P u is 100.
which corresponds to a given Q L) from Table 901.7:1, “Quality Level Analysis by the Standard Deviation Method Upper Quality Index QU or Lowe r Quality Index QL.” If an LSL is not specified, P L is 100.
following equation: 100L UP P Q (Equation 5) Where,
Section 904: Quality Level Analysis (QLA) Page 936 Q is the quality level UP is the percent of test values below the upper specification li mit which corresponds to a given upper quality index (Q U) LP is the percent of test values above the lower specification li mit which corresponds to a given lower quality index (Q L)
Factors.”
jj fffPFf PFf PFf CPF 2 1j 2 2 1 1 (Equation 6) Where, CPF is the composite pay factor f is the price adjustment factors pecified for the applicable Mat erial pursuant to the tables below j is the number of evaluated components PF is the individual pay factor determined for each component
The Contractor shall carry the numbers in the above calculatio ns to significant figures and round them in accordance with AASHTO R 11.
Table 904.1:1 HMA/WMA Weighting Factors Characteristic “f” Factor (%) Mat Density 35 Air voids 35 Voids in the mineral aggregate (VMA) 20 Asphalt Content* 10 *If the individual pay factor fo r asphalt content is less than 0 .75, it will be set at 0.75 for the purpose of calculating payment.
Table 904.1:2 PCCP Weighting Factors Measured characteristic Factor “f” Entrained air 25 Compressive strength 25 Thickness 50
Section 904: Quality Level Analysis (QLA) Page 937
Table 904.1:3 QUALITY LEVEL ANALYSIS BY THE STANDARD DEVIATION METHOD UPPER QUALITY INDEX QU OR LOWER QUALITY INDEX QL Pu or Pl n= 3 4 5 6 7 8 9 10 to 11 12 to 14 15 to 17 18 to 22 23 to 29 30 to 42 43 to 66 67 to x 100 1.16 1.49 1.72 1.88 1.99 2.07 2.13 2.20 2.28 2.34 2.39 2.44 2.48 2.51 2.56 99 — 1.46 1.64 1.75 1.82 1.88 1.91 1.96 2.01 2.04 2.07 2.09 2.1 2 2.14 2.16 98 1.15 1.43 1.58 1.66 1.72 1.75 1.78 1.81 1.84 1.87 1.89 1.91 1.93 1.94 1.95 97 — 1.40 1.52 1.59 1.63 1.66 1.68 1.71 1.73 1.75 1.76 1.78 1.7 9 1.80 1.81 96 — 1.37 1.47 1.52 1.56 1.58 1.60 1.62 1.64 1.65 1.66 1.67 1.6 8 1.69 1.70 95 1.14 1.34 1.42 1.47 1.49 1.51 1.52 1.54 1.55 1.56 1.57 1.58 1.59 1.59 1.60 94 — 1.31 1.38 1.41 1.43 1.45 1.46 1.47 1.48 1.49 1.50 1.50 1.5 1 1.51 1.52 93 1.13 1.28 1.33 1.36 1.38 1.39 1.40 1.41 1.41 1.42 1.43 1.43 1.44 1.44 1.44 92 1.12 1.25 1.29 1.31 1.33 1.33 1.34 1.35 1.35 1.36 1.36 1.37 1.37 1.37 1.38 91 1.11 1.22 1.25 1.27 1.28 1.28 1.29 1.29 1.30 1.30 1.30 1.31 1.31 1.31 1.31 90 1.10 1.19 1.21 1.23 1.23 1.24 1.24 1.24 1.25 1.25 1.25 1.25 1.25 1.26 1.26 89 1.09 1.16 1.18 1.18 1.19 1.19 1.19 1.19 1.20 1.20 1.20 1.20 1.20 1.20 1.20 88 1.07 1.13 1.14 1.14 1.15 1.15 1.15 1.15 1.15 1.15 1.15 1.15 1.15 1.15 1.15 87 1.06 1.10 1.10 1.10 1.10 1.10 1.10 1.10 1.11 1.11 1.11 1.11 1.11 1.11 1.11 86 1.04 1.07 1.07 1.07 1.07 1.06 1.06 1.06 1.06 1.06 1.06 1.06 1.06 1.06 1.06 85 1.03 1.04 1.03 1.03 1.03 1.03 1.02 1.02 1.02 1.02 1.02 1.02 1.02 1.02 1.02 84 1.01 1.01 1.00 0.99 0.99 0.99 0.99 0.98 0.98 0.98 0.98 0.98 0.98 0.98 0.98 83 0.99 0.98 0.97 0.96 0.95 0.95 0.95 0.95 0.94 0.94 0.94 0.94 0.94 0.94 0.94 82 0.97 0.95 0.93 0.92 0.92 0.92 0.91 0.91 0.91 0.91 0.90 0.90 0.90 0.90 0.90 81 0.95 0.92 0.90 0.89 0.88 0.88 0.88 0.87 0.87 0.87 0.87 0.87 0.87 0.87 0.87 80 0.93 0.89 0.87 0.86 0.85 0.85 0.84 0.84 0.84 0.83 0.83 0.83 0.83 0.83 0.83 79 0.91 0.86 0.84 0.82 0.82 0.81 0.81 0.81 0.80 0.80 0.80 0.80 0.80 0.80 0.79 78 0.88 0.83 0.81 0.79 0.79 0.78 0.78 0.77 0.77 0.77 0.76 0.76 0.76 0.76 0.76 77 0.86 0.80 0.77 0.76 0.75 0.75 0.74 0.74 0.74 0.73 0.73 0.73 0.73 0.73 0.73 76 0.83 0.77 0.74 0.73 0.72 0.72 0.71 0.71 0.70 0.70 0.70 0.70 0.70 0.70 0.70 75 0.81 0.74 0.71 0.70 0.69 0.69 0.68 0.68 0.67 0.67 0.67 0.67 0.67 0.67 0.66 74 0.78 0.71 0.68 0.67 0.67 0.65 0.65 0.65 0.64 0.64 0.64 0.64 0.64 0.64 0.63 73 0.75 0.68 0.65 0.64 0.63 0.62 0.62 0.62 0.61 0.61 0.61 0.61 0.61 0.61 0.60
Section 904: Quality Level Analysis (QLA) Page 938 Table 904.1:3 QUALITY LEVEL ANALYSIS BY THE STANDARD DEVIATION METHOD UPPER QUALITY INDEX QU OR LOWER QUALITY INDEX QL Pu or Pl n= 3 4 5 6 7 8 9 10 to 11 12 to 14 15 to 17 18 to 22 23 to 29 30 to 42 43 to 66 67 to x 72 0.73 0.65 0.62 0.61 0.60 0.59 0.59 0.59 0.58 0.58 0.58 0.58 0.58 0.58 0.57 71 0.70 0.62 0.59 0.58 0.57 0.57 0.56 0.56 0.55 0.55 0.55 0.55 0.55 0.55 0.54 70 0.67 0.59 0.56 0.55 0.54 0.54 0.53 0.53 0.52 0.52 0.52 0.52 0.52 0.52 0.52 69 0.64 0.56 0.53 0.52 0.51 0.51 0.50 0.50 0.50 0.49 0.49 0.49 0.49 0.49 0.49 68 0.61 0.53 0.50 0.49 0.48 0.48 0.48 0.47 0.47 0.47 0.46 0.46 0.46 0.46 0.46 67 0.58 0.50 0.47 0.46 0.45 0.45 0.45 0.44 0.44 0.44 0.44 0.43 0.43 0.43 0.43 66 0.55 0.47 0.45 0.43 0.43 0.42 0.42 0.42 0.41 0.41 0.41 0.41 0.41 0.41 0.40 65 0.51 0.44 0.42 0.40 0.40 0.39 0.39 0.39 0.38 0.38 0.38 0.38 0.38 0.38 0.38 64 0.48 0.41 0.39 0.38 0.37 0.37 0.36 0.36 0.36 0.36 0.35 0.35 0.35 0.35 0.35 63 0.45 0.38 0.36 0.35 0.34 0.34 0.34 0.33 0.33 0.33 0.33 0.33 0.33 0.33 0.32 62 0.41 0.35 0.33 0.32 0.32 0.31 0.31 0.31 0.30 0.30 0.30 0.30 0.30 0.30 0.30 61 0.38 0.30 0.30 0.30 0.29 0.28 0.28 0.28 0.28 0.28 0.28 0.28 0.28 0.28 0.28 60 0.34 0.28 0.28 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 59 0.31 0.27 0.25 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 0.23 58 0.30 0.25 0.23 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 57 0.25 0.20 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 56 0.20 0.18 0.16 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 55 0.18 0.15 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 0.13 54 0.15 0.13 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 53 0.10 0.10 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 52 0.08 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 51 0.05 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Note: For negative values of Qu or Ql, Pu or Pl is equal to 10 0 minus the table value for Pu or Pl. If the value of Qu or Ql does n ot correspond exactly to a figure in the table, use the next lower figure.
Section 904: Quality Level Analysis (QLA) Page 939 Table 904.1:4Pay Factors Pay factor Minimum Required Percent of Work Within Specifications Limits for a Gi ven Pay Factor (Pu+PL) – 100 n= 3 4 5 6 7 8 9 10 to 11 12 to 14 15 to 17 18 to 22 23 to 29 30 to 42 43 to 66 67 to 1.05 — — — — — 100 100 100 100 100 100 100 100 100 100 1.04 — — — — 100 99 97 95 96 96 96 97 97 97 97 1.03 — — — 100 98 96 94 92 93 93 94 95 95 96 96 1.02 — — — 99 97 94 91 89 90 91 92 93 93 94 94 1.01 100 100 100 98 95 92 89 87 88 89 90 91 92 92 93 1.00 69 75 78 80 82 83 84 85 86 87 88 89 90 91 92 0.99 66 72 76 78 80 81 82 83 84 85 86 87 89 90 91 0.98 64 70 74 76 78 79 80 81 82 84 85 86 87 88 90 0.97 63 68 72 74 76 77 78 79 81 82 83 84 86 87 88 0.96 61 67 70 72 74 75 76 78 79 81 82 83 84 86 87 0.95 59 65 68 71 72 74 75 76 78 79 80 82 83 84 86 0.94 58 63 67 69 71 72 73 75 76 78 79 80 82 83 85 0.93 57 62 65 67 69 71 72 73 75 76 78 79 80 82 84 0.92 55 60 63 66 68 69 70 72 73 75 76 78 79 81 82 0.91 54 59 62 64 66 68 69 70 72 74 75 76 78 79 81 0.90 53 57 61 63 65 66 67 69 71 72 74 75 77 78 80 0.89 51 56 59 62 63 65 66 68 69 71 72 74 75 77 79 0.88 50 55 58 60 62 64 65 66 68 70 71 73 74 76 78 0.87 49 53 57 59 61 62 63 65 67 68 70 71 73 75 77 0.86 48 52 55 58 59 61 62 64 66 67 69 70 72 74 76 0.85 46 51 54 56 58 60 61 62 64 66 67 69 71 72 75 0.84 45 49 53 55 57 58 60 61 63 65 66 68 70 71 73 0.83 44 48 51 54 56 57 58 60 62 64 65 67 69 70 72 0.82 43 47 50 53 54 56 57 59 61 62 64 66 67 69 71 0.81 41 46 49 51 53 55 56 58 59 61 63 64 66 68 70 0.80 40 44 48 50 52 54 55 56 58 60 62 63 65 67 69 0.79 39 43 46 49 51 52 54 55 57 59 61 62 64 66 68 0.78 38 42 45 48 50 51 52 54 56 58 59 61 63 65 67 0.77 36 41 44 46 48 50 51 53 55 57 58 60 62 64 66
Section 904: Quality Level Analysis (QLA) Page 940 Table 904.1:4Pay Factors Pay factor Minimum Required Percent of Work Within Specifications Limits for a Gi ven Pay Factor (Pu+PL) – 100 n= 3 4 5 6 7 8 9 10 to 11 12 to 14 15 to 17 18 to 22 23 to 29 30 to 42 43 to 66 67 to 0.76 35 39 43 45 47 49 50 52 54 56 57 59 61 63 65 0.75 33 38 42 44 46 48 49 51 53 54 56 58 60 62 64 Reject Values less than those shown above Note: If the value of (Pu+PL) – 100 does not correspond to a ( Pu+PL) – 100 value in this table, use the next lower (Pu+PL) – 100 value
Section 905: Quality Assurance for Minor Paving Page 941