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APPENDIX D Ancillary Issues
Pages 157-172

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From page 157... ... Portable WIM scales were deployed on potential scale bypass routes during periods when permanent main fine scales were open and closed. The applied data analysis addressed day-of-week and time-of-day patterns for potential overweight violations on bypass routes. Read the entire page →
From page 158... ... The table concludes with average observed Excess ESALs for violators, the proportion of violators for trucks exhibiting Excess ESAI~s and Bridge Formula violations. The table contains separate data summaries for FHWA Vehicle Class trucks, defined as follows: Type 9 Five-Axle Single Trailer Trucks Type 11 Five or Less Axle Multi-Trailer Trucks A comparison between California main line and diversion route WIM data indicated insignificant differences in terms of observed average gross weights, including the proportion of overweight trucks. Read the entire page →
From page 159... ... Public Airport ~~ -- -- -- Utility ~ -- -~ ~- County Boundary I Railroad Population Center � Town, Small City ~I Land Figure I Map showing California Truck Scale Bypass Route 3 Apendix D Read the entire page →
From page 160... ... Summary of Portable WIM Data on California Diversion Route Sample Size Average Gross Weight Average Axle ~ Weight Average Axle 2 Weight Average Axle 3 Weight Average Axle 4 Weight Average Axle 5 Weight Proportion Overweight Trucks Axle ~ Proportion Overweight Axle 2 Proportion Overweight Axle 3 Proportion Overweight Axle 4 Proportion Overweight Axle 5 Proportion Overweight Average ESALs Average Excess ESALs Proportion Exceeding ESALs Bridge Formula Violation Rate 236 484 55,854 51,849 9,405 8,598 12,933 14,128 12,087 10,235 11,295 9,787 11,140 10,034 .05 .05 .09 .03 .09 .04 .04 .05 1.4 1.9 .07 .025 .05 .02 .02 1.3 1.6 .08 .004 The majority of overweight violations occurred during the early morning hours, i.e., between 3 a.m. and 8 a.m., with the highest single-hour violation occurrence between 6 a.m. Read the entire page →
From page 161... ... Date Day flour 1 0/2/95 1 0/3/95 1 013195 1 0/3/95 1 013195 1 0/3/95 1 0/3J95 1 0/3/95 1 0/3/95 1 0/3/95 1 0/3/95 1 Ot3/95 1 0/3195 1 0/3/95 1 0/3/95 1 0/3/95 1 0/3/95 1 013195 1 0/3/95 1 0/3/95 1 0/4/95 1 0/4/95 1 0/4/95 1 0/5/95 1 015195 1 015195 1 0/5195 1 0/5/95 1 015195 1 0/5J95 1 0/5/95 1 OJ5/95 1 0/5/95 1 0/5/95 1 0/5195 1 0/6195 Friday 1 016/95 1 016195 1 016195 1 0/6/95 1 0/6/95 1 0/6/95 1 0/6195 1 0/10195 Tuesday 1 0/10/95 1 0/10/95 10/10/95 Monday 1 8 Tuesday 1 2 3 4 4 5 s 5 6 6 6 6 8 9 10 10 18 18 18 Wednesday 1 5 21 23 o Thursday Excess ESALs 1.8 2.2 2.4 0.5 0.4 3.7 1.3 1.5 4.1 0.3 0.8 0.9 1.3 6.4 1.9 0.4 0.6 1.8 2.0 2.9 1.0 5.5 3.3 1.8 1 1.1 5.3 0.9 1.2 4.7 2.9 0.2 2.1 3.4 2.0 0.1 2.9 2.0 2.1 2.8 0.9 0.8 0.1 0.9 0.1 1.0 1.1 0.5 5 5 is 6 8 8 8 8 3 8 9 10 10 11 21 23 o o 6 Excess ESAL Violations on California By-pass Route Type 9 and I 1 Trucl;s Table 2. Excess ESAL Violations on California Bypass Route 5 Apendix D Read the entire page →
From page 162... ... The table concludes with average observed Excess ESALs for violators, the proportion of violators for trucks exhibiting Excess ESALs and Bridge Formula violations. Appendix D 6 Read the entire page →
From page 163... ... Small City ~ Sty SR, Road, Hwy Rumor Airfield - Major Cot State Route US Highway Utility - ' ~ Railroad � Point of interest Figure 2. Map Showing Flonda Truck Scale Bypass Route ? Read the entire page →
From page 164... ... Trucks traveling the bypass route were only slightly heavier on average, i.e., 63,691 pounds versus 61,933 pounds, than those on the main line. However, a statistically significant increase, i.e., 25.8 versus 15.1 percents, was observed in the proportion of gross-weight ~ This higher-than-expected range is likely due to the calibration of the TTI WIM equipment . Read the entire page →
From page 165... ... While fewer trucks were observed to violate the gross weight limit on the main line route, those trucks which violated this limit tended to do so by a greater margin; e.g., Me average violation severity being 7,739 pounds versus 4,056 pounds on the bypass route. This observed effect is likely due to the larger main line truck volume. Read the entire page →
From page 166... ... Date Day Hour Excess ESALs 7/14/95 Friday 17 8.8 7/14/95 Friday 21 1.3 7/14/95 Friday 22 2.4 7/15/95 Saturday 1 15.2 7/15/95 Saturday 5 0.5 7115195 Saturday 7 2.7 7~15/95 Saturday 9 24.2 7/15195 Saturday 22 0.2 7/16195 Sunday 23 16.4 7/17/95 Monday 1 23.9 7/17/95 Monday ~15.2 7/17/95 Monday ~ 2 15.3 7/17/95 Monday 15 ~7.4 7/17/95 Monday 15 4.3 7/17/95 Monday 16 16.9 7/17195 Monday 17 13.4 7/17/95 Monday 17 9.1 7/17/95 Monday 17 14.6 7/17/95 Monday 23 12.5 7/18/95 Tuesday 3 16.1 7/18/95 Tuesday 3 2.7 7118195 Tuesday 6 17.2 7/1 8195 Tuesday 7 18.9 7/1 B/95 Tuesday 9 17.6 7/1 B/95 Tuesday 13 B.9 7/~/95 Tuesday 16 2.4 7/~/95 Tuesday 16 14.1 7/~/95 Tuesday 16 6.4 7/18/95 Tuesday 17 6.5 7/18195 Tuesday 17 9.2 7/18/95 Tuesday 21 4.0 7/1 B/95 Tuesday 23 0.5 7~19/95 Wednesday ~6.7 7/19/95 Wednesday 3 22.8 7/19/95 Wednesday 4 15.4 7/19/95 Wednesday 6 21.4 7/19/95 Wednesday 7 18.6 7/19/95 Wednesday 7 17.7 7/19195 Wednesday 7 23.1 7/19195 Wednesday 7 26.4 7/19/95 Wednesday 11 5.3 7/19/95 Wednesday 11 6.4 Excess ESAL Violations on Florida By-pass Route Table 4. Excess ESAL Violations on Flonda Truck Scale Bypass Route Appendix D 10 Read the entire page →
From page 167... ... However, trucks samples observed to use bypass routes were consistently more likely to exhibit higher average ESALs and Excess ESALs. Similar travel time trends were observed between the two states; despite differing hours of main-line permanent scale operation. Read the entire page →
From page 168... ... State Highway Agency Permits Record Systems Truck overweight permit record-keeping practices were addressed with state highway agency officials in Ohio and Texas, in addition to officials of participating field study states. With a single exception, record-keeping systems for interviewed states did not provide adequate specificity to allow matching of permit-issuance data with WIM records. Read the entire page →
From page 169... ... Lur~dell did offer to supply interested state agencies with the TxDOT software in order to allow their tracking of permitted overweight vehicles. Possible WIM Data Confounding Due to Permit-Issued Overloads A literature survey was attempted to gather insight regarding the possible weightdata confounding effect associated with permitted overweight truck presence in a traffic stream. Read the entire page →
From page 170... ... Truck Presence While the presence of permitted overweight trucks in the traffic stream can not be detected by WIM systems, the distinct possibility exists for its confounding the recorded traffic stream compliance with legal weight limits. However, the literature has demonstrated that traffic observations provide a valid indication of violations in the absence of permitted truck flow data. Read the entire page →
From page 171... ... and Thom, R.G. Gross Weight Distributions as a Function of Weight Limits, Transportation Research Record 1313, Transportation Research Board, Washington, D.C. Read the entire page →

From page 157...

... Portable WIM scales were deployed on potential scale bypass routes during periods when permanent main fine scales were open and closed. The applied data analysis addressed day-of-week and time-of-day patterns for potential overweight violations on bypass routes.

APPENDIX D Ancillary Issues Pages 157-172

APPENDIX D Ancillary Issues
Pages 157-172