LOCAL URBAN TRANSIT BUS IMPACT ON PAVEMENTS

Bus transit systems provide a valuable service to many residents livin g within urban areas. Like other vehicles, buses depend on paved stree ts and roads for a smooth ride. The pavement wear due to truck traffic has been monitored and researched for many years. The effects of urba n transit buses on pavements owned and maintained by local governments are examined from the following three perspectives: (1) Pavement desi gn; (2) pavement condition data analysis; and (3) visual observations. Each of the three perspectives suggests that significant pavement dam age is caused by transit bus traffic. Another analysis probed pavement s' damage if buses had a third axle. There are a number of significant conclusions offered which include the following: (1) Fully loaded tra nsit buses exceed the California legal axle limit; (2) the constructio n cost to accommodate transit buses is approximately 5% for arterials and 58% for collectors; (3) the addition of a third axle will reduce t he pavement damage by approximately three times; and (4) another appro ach to reduce pavement damage would be to use lighter-weight materials in the manufacturing of transit buses.