Study On Seismic Behavior Of High-Rise Frame Structure In Karst Area

Karst geology is distributed throughout one-third of our country. With the rapid economic development, infrastruction was inevitably carried out in karst area.accordingly, more attention was paid on seismic research w hich architecture built in karst area.now the mainstream of the seismic de sign method is still using the traditional design thinking which analyze t he foundation, basis and upper part of the structure separately, lacking res earch on seismic performance and collapse mechanism. Result of this traditi onal method will differ greatly from actual condition, unable to improve the seismic performance. It is necessary to develop new research on eart hquake damage mechanism in karst area.This paper mainly research on failure mechanism of karst foundation-raft foundation-frame structure through analyzing whose interaction and failure mode. The main work is as follow:(1) Briefly reviews the development of the seismic theory,pointing out the advanced research hotspot will be the seismic conception focus onperformance-based design or displacement-based design; briefly explain earthquake damage mechanism of reinforced concrete through elaborating the development of plastic hinges research. The main failure patterns include beam hinge model, column hinge model and beam hinge model. Briefly reviews the domestic and international development of interaction, predicting the development trend could be appling the analyze method of interaction to practical engineering.(2) Elaborate the analyze method of interaction through three aspects: foundation, basis and upper part of the structure. The change of superstru cture floor, foundation stiffness and basis stiffness could influence seismic response of interaction system, only choosing appropriate basis, foundation and superstructure parameters could enhance the anti-earthquake performanc-e of structure system.(3) Elaborate the characteristic of karst foundation and earthquake damage,the measure of improving seismic ability.To enhance the earthqua-ke resistant of architecture in karst area, mainly from the characteristics of karst geology, trying to aviod sites of low capacity or treating the karst foundation to enhance the capacity of foundation.(4) Built interaction model of karst foundation-raft foundation-12 floors frame structure and the corresponding solid base hypothesis model of raft foundation-12 floors frame structure. Results showed that interaction designing method would make structure much more safer from seismic action.(5) To analyze seismic response of same 5 floors frame structure interaction model and solid base hypothesis analysis model,the main conclusions were as follows traditional solid base hypothesis designing method ignores the danger of elastic-plastic state when structure enters, which might trigger a damaging earthquake much easily. To a certain extent, interaction designing method might ameliorate mechanical performance and enhance seismic response of structure.