Design Parameters For Anti-collision System Between Adjacent Buildings Under Earthquakes

Investigations into past several strong earthquakes have shown that the failure in engineering structures was the main reason for the heavy losses in the earthquakes. Pounding between adjacent buildings or parts of the same building due to earthquakes, which is one of the most typical seismic damages, has often been recorded as an important cause of severe structural damage or even collapse.Connecting the dampers between adjacent buildings is one of the best methods to mitigate the damages due to pounding. However, pounding between adjacent buildings with energy dissipation devices is considered to be fully avoided in previous studies, which is not exactly accordant to the real situation. Adjacent buildings connected with anti-collision system including two parameters (stiffness coefficient K and damping coefficient C) is investigated in this study, and the effect of pounding, earthquake characters, distance, height ratio of adjacent buildings and structural characters such as stiffness, period, stiffness ratio and period ratio of adjacent buildings on the optimum parameters of the system is discussed.There are three sections of this study:(1) The structures are set up as a separable reinforced concrete solid model in ANSYS/LS-DYNA for the time-history analysis. Results show that pounding between adjacent buildings has a significant effect on the reduction of the ranges of optimum parameters. And earthquake characters and separated distance between adjacent buildings also have obvious influence on the optimum parameters.(2) The adjacent buildings are simplified as two single freedom systems connecting with two damper systems, one of which is considered as the anti-collision system and the other is to consider the pounding between adjacent buildings. A large number of earthquake records are input into the system for a statistic analysis. The relationship between optimum parameters of anti-collision system and structural characters is concluded in this section.(3) Six group of adjacent buildings are set up as solid models just like section (1). The height ratio of adjacent structures are different in each group to discuss the relationship between heights ratio and optimum parameters of anti-collision system. Results from solid models are compared with the result of section (2), and the functions of optimum parameters are improved in this section.