ABSTRACT
The Federal Highway Administration (FHWA), by a memorandum dated November 15, 2013, requires a state to certify that it either does not permit operation of Specialized Hauling Vehicles (SHV) or conducts bridge force effects load rating analyses using the standard American Association of State Highway and Transportation Officials (AASHTO) HS20 or HL93 loads and applicable SHV load configurations. Texas does allow operation of SHVs, although the number and range of actual gross vehicle weights, axle weights, axle configurations, and spacing was previously unknown. AASHTO has adopted one SHV Notional Load Rating (NRL) configuration for screening purposes and four SHV bridge load rating configurations (SU4, SU5, SU6 and SU7) which are now incorporated in the Manual for Bridge Evaluation (MBE). However, due to the specific types of SHVs this project found operating within Texas, it may be necessary to supplement the AASHTO SHV load configurations with SHV configurations unique to Texas to ensure accurate bridge load rating practices. This paper discusses the network level bending moment analysis that screened the approximately 32,000 Texas bridges for impacts of the actual SHV configurations found operating in Texas, determined candidates for posting and calculated an initial posting load for the selected bridges.
