Superheavy vehicles, also called superloads, have non-standardized loading configurations as well as high gross vehicle weights (GVW) and axle loadings, all of which may cause unexpectedly greater distresses on jointed plain concrete pavements (JPCP) than those caused by conventional vehicle class types categorized by the Federal Highway Administration (FHWA). In general, superloads include “Implements of Husbandry” and “Superheavy Loads”, both known to be the main types of heavy transport vehicles in the Midwestern region of the United States. To characterize non-standardized loading configurations of superloads, a mechanistic analysis approach is needed for predicting potential damage to JPCPs. In this paper, critical loading locations are determined and categorized according to the superload loading configuration for each superload generating critical pavement responses for both bottom-up transverse cracking and top-down transverse cracking. Critical pavement responses of JPCPs under critical loading conditions for each superload are calculated by performing finite element analysis and are then converted to damage ratios by comparing them with critical pavement responses resulting from FHWA class 9 truck loading using various available transfer functions based on concrete fatigue test results. The resulting critical loading location for each superload category can then be derived easily and the potential for damage to the JPCP pavement systems by each superload can be determined by comparing fatigue damage ratios.
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