| In the connected super high-rise structure,the structural components at the joint of the connected structure and the tower play the role of transmitting the force and deformation between the connected towers.Under strong earthquake,the floor is undoubtedly the vulnerable part in the connected structure.In addition,in order to control the lateral displacement index of the structure and strengthen the cooperative anti lateral action between the central core tube and the outer frame column,it is usually along the structure In order to improve the overall lateral stiffness of the structure,several layers of rigid strengthening layer are set in height,but the setting of strengthening layer will inevitably lead to the sudden change of the vertical stiffness of the structure.Under the earthquake,the reinforced floor and the adjacent floor are prone to cumulative damage.More and more connected super high-rise structures,the seismic damage control of vulnerable parts under strong earthquake are urgent problems to be studied and solved.Some scholars have proposed the connection mode between connected building and tower and the strengthening story damping mode based on energy dissipation,but there are still problems in the strong earthquake damage control of connected super high-rise structure at present:(1)what is the effect of the existing energy dissipation methods on the strong earthquake damage control of vulnerable parts of connected complex super high-rise structure?(2)What are the effects of different seismic isolation methods and parameters on the damage control effect of the vulnerable parts of the connected complex super high-rise structure?(3)How to reasonably evaluate the performance level of the vulnerable parts of the connected complex super highrise structure after the earthquake? To solve the problems,this paper takes a connected super high-rise structure as the research object,adopts isolation bearings,buckling restrained braces and viscous dampers to control the structural damage under strong earthquake,compares the damage control effect of vulnerable parts of the floor under different seismic isolation methods and parameters,and uses a variety of material plastic damage parameters to evaluate the damage of the floor Then,the plastic damage parameters of materials are introduced into the seismic vulnerability analysis of structures.From the perspective of failure probability,the reliability of the connected complex super high-rise structure is evaluated by the overall index and component damage index,and the damage control evaluation index and method of the super high-rise structure floor are supplemented.The conclusions of this paper are as follows :(1)In this paper,a complex super high-rise structure with double towers and strengthened stories is taken as the research object.The elastic-plastic dynamic time history analysis of the structure is carried out by using the elastic floor model and the elastic-plastic floor model respectively with the sausage structural analysis software.The results show that the frame beams,columns,shear walls and floor members of the elastic floor model structure are basically in the state of slight damage and no damage,and only the shear wall coupling beams reach the state of severe damage;while the elastic-plastic floor model structure has obvious plastic damage concentration area in the connecting part with two towers and the floor near the strengthened floor,and the floor at the connecting part is in the state of various working conditions 13% of them are moderately damaged and 8.25% of them are seriously damaged.The floor slab at the outrigger truss of the strengthened floor is seriously damaged under various working conditions.The connection between the connected structure and the tower and the members near the strengthened floor are the vulnerable parts of the structure.(2)In view of the weak parts of the structure,the corridor isolation bearing connection scheme is adopted for the connection between the main building and the connecting body,and three kinds of vibration reduction outrigger truss schemes are adopted for the strengthening layer: 1.The web members of the outrigger truss are replaced with buckling restrained braces(BRB);2.The velocity viscous damper is set on the upper part of the herringbone diagonal braces of the outrigger truss;3.BRB braces and viscous dampers are arranged at the same time The following conclusions are drawn from the macro parameters and component damage before and after the shock absorption scheme: after the shock absorption scheme is adopted,the overall index of the structure changes little under the 7 degree earthquake,and the shock absorption scheme can effectively reduce the interlayer displacement angle mutation at the strengthened layer of the structure;in the aspect of damage,the plastic damage of the original structure at the connection of the connecting body and the tower and the floor near the strengthened layer is concentrated and reaches the strict limit under the strong earthquake Heavy damage level.The results show that the seismic isolation scheme can effectively reduce the damage of vulnerable floor and improve the seismic performance of the structure.(3)In order to reasonably evaluate the damage level of the connected complex super highrise structure after earthquake,two groups of long and short period seismic waves are selected respectively,and the plastic damage limit state index of the floor material is introduced to analyze the seismic vulnerability of the structure,and the damage probability and reliability of the structure and floor are evaluated from the perspective of transcendental probability.The results show that the damage probability of the structure increases by less than 11% under the action of long-period seismic wave;under the strong earthquake,the exceeding probability of the maximum severe damage of the floor can be reduced by 75% and 48% under the strong earthquake intensity of 8 degrees,which indicates that the structure is more sensitive to the response of long-period seismic wave,and the damping scheme can effectively reduce the original structure The exceedance probability of the ultimate failure state of the floor can control the strong earthquake damage of the structural floor. |
