Analysis On Seismic Mitigation Efficiency For Flexible Suspension Structure

With the rapid development of economy and technology,high buildings are becoming more and more popular with incomparable number and scale over the past time.While being with the diversification in structural scheme,they are indubitably facing with the highly probable and serious risks resulting from various natural disasters.It is commonly considered that high rise buildings should be with higher safety architecture standards.As a new type of building structure,suspending structure has become more and more striking in architecture industry.It accords with load passing principles in natural world and could fully utilize the mechanical properties of high strength building materials.It is clear from previous research work that suspending structures are being with satisfied seismic mitigation performance and utility adaptation,plus with good development prospect.At present,most of the research work has been concentrated to suspending structures with rigid suspension parts.It is expected,however,that the structures with soft suspension parts should exhibit composite seismic mitigation performance to further reduce seismic dynamic responses.Few related research work has been reported.The governing equations were formulated for a 21 storey high rise building in 3 suspending sections with soft suspension points.It is from the Lagrange Equation in structural dynamics.The solution work was programmed with MATLAB language to present the whole dynamic response of the structure under different seismic waves input.The dynamic response diagram of the upper suspension structure is compared with that of the rigid suspension points.The computation results show that seismic dynamic responses of suspending structure with soft suspension points could be further reduced,comparing to that of rigid suspension points.Both the inter-storey displacements and storey accelerations could be notably reduced with more even distribution along the building height.Both the damping coefficients of storey dampers and the stiffness coefficients of suspension points could exert influence to seismic mitigation efficiency.Within the discussed range of the 2 coefficients,both the storey displacements and the storey accelerations exhibit the tendency of reducing and the increasing,which meant the existence of the optimal combination of the 2 coefficients.It might be expected that the damping coefficient is about 500 k N.s.m-1 while the stiffness coefficients is 2000kN.m^-1.