Sliding Isolation Frame Structure Model Design And Analysis

Sliding isolation technology is one of the main isolation method to reduce theearthquake influence on upper structure. The vibration isolation effect is good, but theresearch on the vibration isolation performance at present still has some defects.Therefore, this article designs a sliding isolation frame structure calculation model oftwo across five layers. An corresponding scale experiment model structure is designedand made. And, the model structure is based on the SAP2000finite element analysis.The isolation performance of the sliding isolation frame structure is studied. Main workand research content is as follows:(1)To study the influence of structural mass to structural vibration, the floorinterlayer shear and the pillar bottom pressure, and to establish the vibration calculationmodel of frame structure accurately, a sliding isolation frame structure calculationmodel of two across five layers is designed and the corresponding SAP2000finiteelement analysis model is established. By taking4methods of defining the framestructure mass source in SAP2000to design and compare, the changes in naturalvibration period, the floor interlayer shear and the pillar bottom pressure of modelstructure is discussed, and a basis for further analysis is provided.(2)To study the isolation performance of the friction pendulum foundation slidingisolation frame structure, the frame calculation model and the corresponding seismicstructure model is selected as two research objects. The finite element softwareSAP2000is used to modeling, the definition of operating conditions, model calculationanalysis and data extraction. The natural period, floor maximum acceleration response,displacement between floors and interlayer shear forces of the base sliding isolationstructure and corresponding seismic structure in the earthquake is analyzed. The seismic response of two model structures is compared, and the friction pendulum vibrationisolation effect is discussed. Results show that by setting the performance parameters ofthe friction pendulum properly, the damping effect of sliding isolation frame structure isobvious. It can reduce the acceleration response, interlayer displacement and interlayershear forces of the structure significantly. The damping effects of the accelerationresponse reach90%.(3)To study the influence of the friction-sliding isolation plate isolation layerstiffness to the vibration isolation performance of the base isolation frame structurecalculation model, finding the reasonable stiffness of the sliding isolation layer.According to the friction sliding characteristics from the friction-sliding isolation platetest, using SAP2000software modeling and analysis, the isolation effect of twosituations between the upper rigid slab of isolation layer and column root directlysetting the isolation bearing is compared. Results show that the isolation layer stiffnessof setting rigid base isolation frame structure is easy to control, and it can effectivelycontrol the maximum slippage of sliding base. When the isolation layer stiffness of thecalculating model is about2000kN/m, the vibration isolation effect is good. It cansignificantly reduce the displacement between layers, interlayer shear force andacceleration response of the frame structure. The normal circumstances can be reducedby70%.(4)The general similitude law is adopted to design the simulated earthquakeshaking table test model of the isolation frame calculation model structure. And thebasic process of model design is introduced. A double deck chassis design is adopted.The reinforcement area of experimental model structure is made equivalent and theartificial quality of model structure is made equivalent. Results show that the artificialmass set within7-8t is reasonable, the model similarity relation is appropriate and iseasy to implement. The acceleration similarity coefficient is between2and3, and it canreduce the gravity distortion effect of the test model structure well, reduce the noiseinfluence and test error, and the seismic response characteristics of the calculationmodel structure can be better reflected. In addition, the isolation layer stiffness of thetest model structure is appropriate to take250kN/m-500kN/m, at that time the naturalvibration period of the isolation structure is2-3times to the natural vibration period of the seismic structure.