A Novel Seismic Design Strategy for Structures With Complex Geometry

作者：Lago A^*; Sullivan T J; Calvi G M

来源：Journal of Earthquake Engineering, 2010, 14: 69-105.

DOI：10.1080/13632461003651901

• Complex Geometry
• Damper
• Diagrid
• Displacement-Based Design
• Isolation

The construction of structures with complex geometry has become increasingly common in recent years. Though an exact definition for complex structures may not yet be clear, especially in relation to seismic prone regions, there is a general lack of guidance for unusual structures (i.e., structures with inclined walls and columns, double curved enclosures, etc.) in current national building codes. For these reasons this work initially highlights the general challenges involved with the seismic design of complex geometry structures. An innovative seismic design strategy is proposed that isolates the exterior complex structure from the main seismic masses through the introduction of seismic isolation or damping devices at floor edges up the height of the building, with the device characteristics set to effectively use the whole building structure. A distinct advantage of the proposed solution is that it would be applicable to most structures with complex geometry, provided that the exterior structure can resist its self-weight without transfer of gravity forces to the structural core. A case study building is examined to explore the effectiveness of the design concept. Results of nonlinear time-history (NLTH) analyses undertaken using a suite of spectrum-compatible accelerograms indicate that the isolation strategy significantly reduces the potential for damage in the external complex geometry structure. In addition, a new direct displacement-based design (DBD) formulation is proposed for vertically distributed viscoelastic isolation systems. In order to validate the proposed DBD procedure, a suite of complex geometry case study structures of 4, 8, 12, 16, and 20 stories are examined. NLTH analyses are again undertaken in order to validate the proposed concept. The results show that the vertically distributed isolation strategy can provide an efficient seismic design solution for structures with complex geometry and that the proposed direct DBD approach provides an effective means of controlling the seismic response.

• 出版日期2010