Analysis and Forecast of Truck Traffic Loads and the Relative Damage to Pavement Systems as a Function of Axle Configurations
Analysis and Forecast of Truck Traffic Loads and the Relative Damage to Pavement Systems as a Function of Axle Configurations

Author:

Publisher:

Published: 1987

Total Pages: 205

ISBN-13:

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This report is the first in a series regarding a study entitled "Evaluation of Truck Sizes, Weights, and Tire Pressures on Pavement Deterioration", being conducted by the Center for Transportation Research at The University of Texas at Austin. The overall study examines several aspects of possible cause and effect relationships between increasing truck weights, sizes, tire pressures and pavement deterioration. The first phase of this study includes three scenarios. The first is a base scenario, which is characterized by an assessment of the effects on pavements of the entire vehicle fleet operating with currently prescribed weight limits and pre 1973 tire pressures. The second is an existing traffic scenario, characterized by the most recently observed (1984) SDHPT vehicle weight data and tire pressures. The third is a future traffic scenario, whereby hypothetical vehicle configurations are utilized to evaluate a possible way of reducing pavement damage.

Final Report on Road Test One-MD
Final Report on Road Test One-MD

Author: National Research Council (U.S.). Highway Research Board

Publisher:

Published: 1952

Total Pages: 214

ISBN-13:

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Tests were conducted on a 1.1-mi. section of portland- cement-concrete pavement near La Plata, Maryland, to determine the relative effects of four different axle loads on a concrete pavement. The loads employed were 18,000 lb. and 22,400 lb. on single axles, and 32,000 lb. and 44,800 lb. on tandem axles. There were four separate test sections with trucks selected for each section to obtain the highest practicable rate of acceleration between 10 and 40 mph. on the existing road profile. Controlled-traffic tests were conducted from June through December 1950, soil and strain tests made in 1951. The analyses of these data, which included 6,000 soil tests and 12,000 strain and deflection readings, were completed in April 1952.

Improved Characterization of Truck Traffic Volumes and Axle Loads for Mechanistic-empirical Pavement Design
Improved Characterization of Truck Traffic Volumes and Axle Loads for Mechanistic-empirical Pavement Design

Author: Ala R. Abbas

Publisher:

Published: 2012

Total Pages: 0

ISBN-13:

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The recently developed mechanistic-empirical pavement design guide (MEPDG) requires a multitude of traffic inputs to be defined for the design of pavement structures, including the initial two-way annual average daily truck traffic (AADTT), directional and lane distribution factors, vehicle class distribution, monthly adjustment factors, hourly truck distribution factors, traffic growth rate, axle load spectra by truck class (Class 4 to Class 13) and axle type (single, tandem, tridem, and quad), and number of axles per truck. Since it is not always practical to obtain site-specific traffic data, the MEPDG assimilates a hierarchal level concept that allows pavements to be designed using statewide averages and MEPDG default values without compromising the accuracy of the pavement design. In this study, a Visual Basic for Application (VBA) code was developed to analyze continuous traffic monitoring data and generate site-specific and statewide traffic inputs. The traffic monitoring data was collected by 143 permanent traffic monitoring sites (93 automated vehicle classifier (AVC) and 50 weigh-in-motion (WIM) sites) distributed throughout the State of Ohio from 2006 to 2011. The sensitivity of the MEPDG to the various traffic inputs was evaluated using two baseline pavement designs, one for a new flexible pavement and one for a new rigid pavement. Key performance parameters for the flexible pavement included longitudinal (top-down) fatigue cracking, alligator (bottom-up) fatigue cracking, transverse (low-temperature) cracking, rutting, and smoothness (expressed using IRI), while key performance parameters for the rigid pavement included transverse cracking (% slabs cracked), joint faulting, and smoothness. The sensitivity analysis results revealed that flexible pavements are moderately sensitive to AADTT, growth rate, vehicle class distribution, and axle load spectra; and not sensitive to hourly distribution factors, monthly adjustment factors, and number of axles per truck. Furthermore, it was found that rigid pavements are moderately sensitive to AADTT, growth rate, hourly distribution factors, vehicle class distribution, and axle load spectra; and not sensitive to monthly adjustment factors and number of axles per truck. Therefore, it is recommended to estimate the AADTT and the vehicle class distribution from site-specific short-term or continuous counts and obtain the truck growth rate from ODOT Modeling and Forecasting Section (Certified Traffic). As for the other traffic inputs, statewide averages can be used for the hourly distribution factors, axle load spectra, and number of axles per truck; and MEPDG defaults can be used for the monthly adjustment factors.