Abstract: This paper studied the impact of potential structural defects in isolation trenches in practical projects. Taking a 10-story concrete frame isolation structure as a research object, this study used the linear elastic collision model to analyze and discussed the influential parameters of different fillers of the isolation trench, impact gap of the isolation trench, connection form of the pipeline across the isolation trench, etc. The results indicated that the acceleration at the bottom of the structure increased with an increasing collision stiffness. When the isolation ditch was filled with concrete fragments, the acceleration response was the highest, and the structural response gradually increased and tended to stabilize with an increase in the isolation ditch clearance. When the pipeline crossing the isolation trench was rigidly connected or partially filled, the structure produced a significant torsional effect, which increased the risk of damage to the support and structure.

Key words: isolation structure, isolation collision, maintenance of isolation gap, cross isolation gap pipeline, seismic response