Application of bridge health monitoring and wireless early warning systems: effectively enhancing bridge safety

Over the past 20 years, the use of precast segmental techniques for accelerated bridge construction has gained increasing attention in the United States and Europe. Precast segmental bridge construction is a method involving the use of precast production and field mechanical erection. Segmental bridge units are fabricated in a precast factory where reinforcing work and concreting can be achieved by automatic and mechanical operations. Comparing with conventional cast-in-place construction, precast segmental construction has the advantages of accelerated construction while maintaining construction quality due to the better working environment of a precast factory. The work-zone safety is increased because the time associated with high-rise construction is reduced. The traffic disruption is decreased due to a shorter construction time. Furthermore, the environmental impact is minimized, since the land needed for construction purpose is less. As a result, precast segmental bridge construction is especially attractive in environmental sensitive regions and urban areas. Precast segmental construction has been extensively used for bridge superstructures. However, the application of precast segmental substructures is still limited to regions of low seismicity because of the conce on their seismic performance. Moreover, many of the bridges in the United States are old and deteriorating and need reconstruction.

Precast segmental construction of bridge pier systems: short construction time, low environmental impact, and high seismic resistance

Thus, accelerated bridge construction has been one of the focuses of recent bridge engineering research projects. For this reason, collaboration research on accelerated bridge construction for seismic regions was initiated between Taiwan’s National Center for Research on Earthquake Engineering (NCREE) and the U.S. Multidisciplinary Center for Earthquake Engineering Research (MCEER) at University at Buffalo. This research first developed the concepts of precast segmental columns for seismic regions based on literature review and results of analytical studies. Subsequently, large-scale experimental studies were carried out. Results of the studies have shown that the proposed columns exhibited satisfactory seismic performance and impROVed post-earthquake serviceability. Besides, to pROVide early warning for bridge collapse, NCREE has developed bridge health monitoring systems with wireless techniques. The systems can pROVide real time monitoring of safety conditions of bridges and achieve early warning of dangerous conditions for bridge owners to take actions to protect public safety. To increase the public awareness and acceptance of this new bridge construction method, NCREE also constructed a scaled bridge model with wireless health monitoring and warning systems for demonstration.