Development of a Stand-Alone Concrete Bridge Pier Protection System

摘要

In order to prevent vehicles from impacting bridge piers located in the medians of arterial roadways, roadside barriers are warranted. For instances where roadside space is limited, rigid concrete barriers are often used to shield the bridge piers. These concrete barriers need to be anchored so that they do not translate nor rotate during vehicle impacts. If the roadway slabs do not extend far enough into the median in order to provide adequate anchorage, a footing may be required. Therefore, a concrete barrier with a stand-alone concrete footing was designed, constructed, and crash tested. The objective of the study was to evaluate the safety performance of an 813-mm (32-in.) tall, vertical concrete parapet shielding a bridge pier according to the Test Level 3 (TL-3) criteria established by NCHRP Report No. 350. The barrier width and reinforcement were optimized to provide adequate strength at minimal construction costs. A distance of 425 mm (16.75 in.) between the barrier face and bridge pier was determined necessary to prevent critical vehicle snag. The footing was designed to carry the barrier overturning moment during severe impacts, and thus maintaining the offset distance to the front face of the bridge pier. One full-scale crash test was performed with a pickup truck. Following the successful redirection of the pickup, the safety performance of the stand-alone, vertical concrete barrier was determined to be acceptable according to the TL-3 evaluation criteria specified in NCHRP Report No. 350.