Typical Cases and Characteristics of Scour Countermeasures of Ancient Chinese Bridges

Abstract:

Chinese ancient bridge engineering has a long and abundant history， and can well reflect historical features and regional culture of China. However， the performance of the existing ancient bridges has been degraded because of the long-term service and the evolution of natural environment. Especially in recent years， with the intensification of climate change， more ancient bridges have been being damaged， which makes the relevant protection in urgent need. Statistics show that scour causes long-term adverse effect to the foundation and wholistic structure， limiting the service life of ancient bridges. During ancient times， based on the qualitative understanding of the scour， some countermeasures were created and applied， according to the different hydrological and geological conditions. In this paper， combined with the present criteria for the occurrence and development of scour， the mechanism and protection benefit of countermeasures， such as cutwaters， riprap-foundations and pilings， which were adopted by three representative existing ancient bridges， are analyzed. Furthermore， the protection effect index is proposed from three aspects including disaster types， the application scope and the service performance. Besides， the criterion is improved by service performance index， based on which some suggestions are provided for the protection and repair work of ancient bridges.