Dynamic Response and Safety Evaluation for the Adjacent Viaduct Under the Influence of Subway Connecting Passage Blasting

In the process of subway blasting and excavation in a complex urban environment, ensuring the safety and stability of adjacent important ground structures is the key content of the project. To ensure the safety and stability of the viaduct during the blasting construction, the paper is based on the blasting excavation project of the subway connecting passage between Jiedaokou Station and Xiaohongshan Station of Wuhan Metro Line 8. Through on-site blasting vibration monitoring and combined with ANSYS/LS-DYNA, the dynamic response characteristics of the viaduct under the blasting excavation of the subway connecting passage are analyzed. And the reliability of the numerical model is verified by field monitoring data. Furthermore, the influence of blasting on viaduct under different blasting distances is further calculated, and the blasting response characteristics of different parts of the viaduct are discussed and summarized. Finally, to evaluate and predict the impact of blasting vibration concisely and effectively, a mathematical expression describing the relationship between the vibration velocity and the displacement of the viaduct pier and bearing is proposed. Combined with the "Code for seismic design of urban bridges," it is proposed that the blasting control vibration velocity of viaduct under the action of the underpass blasting of the subway connecting passage is 4.55 cm s(-1).