Research On Seismic Isolation Technology Of Prefabricated Houses Based On Energy Consumption Principle

China is one of the countries with the most frequent earthquakes in the world.Among them,the dwellings in large areas are severely damaged.In order to prevent earthquakes from damaging buildings,traditional seismic methods are often used to passively enhance the seismic resistance of superstructures.However,the traditional seismic method is costly,and the seismic effect is not as effective as the active isolation technology.In addition,the connection strength of prefabricated houses is lower than that of cast-in-situ houses,which results in that the prefabricated houses have worse seismic performance than traditional cast-in-situ houses.Therefore,based on the principle of energy consumption,this paper studies the basic isolation technology of prefabricated houses.According to the literature,the seismic waves that often damage buildings are horizontal seismic waves and relatively few vertical seismic waves.Therefore,this paper optimizes and improves the connection construction technology between the superstructure and foundation of prefabricated houses.On the basis of the seismic isolation device,a new assembled flexible seismic isolation device is developed which is conducive to the promotion of assembled buildings and the improvement of the assembly rate,and isolates horizontal seismic waves.In this paper,based on the theory that the period of the seismic isolation structure is prolonged and the structural response will be reduced,the simulation model is established using ANSYS software.For the reinforced concrete frame structure residential buildings with particularly weak connection nodes in the multi-layer prefabricated residential buildings,the basic isolation is carried out.The dynamic response analysis of the residential buildings during the earthquake,the determination of the structure of the new type of flexible isolation device and the analysis of the energy dissipation under the cyclic reset load,and the vibration isolation performance of the device through the scale model test of vibration isolation performance.Research indicates:(1)Under the action of three 7-degree rare earthquake waves such as El-Centro wave,Lanzhou wave and Tangshan artificial wave,the modal analysis of prefabricated houses shows that the third-order natural vibration period of isolated houses is non-isolated houses Is 2.88 times,the difference is the largest,indicating that the anti-torsion effect is the most obvious improvement;followed by the first-order natural vibration period,the difference is2.57 times,indicating that the resistance to translational displacement deformation is also more obvious.The inter-layer displacement and inter-layer displacement angle of isolated houses are significantly smaller than those of non-isolated houses,and under the action of a7-degree rare earthquake wave in Lanzhou,the isolated structure can continue to be within1/550 of the elastic inter-layer displacement angle limit instead of The isolation structure has exceeded the limit and entered a plastic state,indicating that this isolation house is under the action of Lanzhou wave,and the isolation effect is the best;the maximum acceleration on the top of the prefabricated house is much smaller than that of the non-isolated prefabricated house,which is in At the bottom,the maximum acceleration at the top is the minimum value,indicating that this isolation house is under the action of Lanzhou wave,and the isolation effect is the best.(2)Based on the background of prefabricated residential buildings,through literature research,we can see that the existing seismic isolation devices have the disadvantages of complex structure,high cost,poor durability,and inconvenient maintenance and replacement.Therefore,corresponding improvements have been made.A new type of assembled flexible isolation device.Based on the rolling isolation friction principle,steel balls,U-shaped mild steel,and steel plates were selected for the design of the assembled flexible isolation device.The assembled flexible isolation device was determined through theoretical calculation and analysis.The specific structure and detailed parameters.(3)Numerical analysis of the quasi-static cyclic reciprocating displacement loading of the flexible isolation device shows that the isolation device has a certain initial stiffness,a full hysteresis curve,and good energy dissipation.When the displacement is loaded to a maximum amplitude of 42 mm,The equivalent horizontal stiffness of the vibration isolation device is 3.4k N / mm,the maximum dissipated energy is 17041.2 J,the equivalent damping ratio is 20.32%,and the energy consumption is continuously improved with the increase of the loading displacement.After the loading,the device still has A certain level of stiffness.Compared with the research of Cheng Bei et al.From Beijing University of Architecture and others on U-shaped steel rod damper rubber isolation bearings,the conclusions are consistent.(4)Using the principle of geometric similarity,through a scale test of the seismic isolation performance of the shaker of 1: 3,Tangshan artificial wave,El-Centro and Lanzhou were carried out on a steel frame with a diameter of 8mm on the upper part and a two-layer steel frame with a diameter of 12 mm Flexible base isolation and non-isolation tests under three7-degree rare earthquake waves.From the test results,it is known that,with the exception of Lanzhou waves,for the same superstructure and the same rare earthquake wave,the maximum acceleration of the isolated structure of each upper layer is less than the maximum isolated non-isolated acceleration of the corresponding number of layers;As the number increases,the maximum acceleration gradually increases;the higher the stiffness of the upper part,the smaller the acceleration peak value,which indicates that the isolation effect of the upper structure and the isolated structure is better.For the upper steel frame structure with a diameter of 8 mm,the average maximum acceleration value of the entire frame structure can be reduced by 21.55% and 17.73% under the action of Tangshan artificial wave and El-Centro wave,respectively.Under the action of Lanzhou wave,the maximum acceleration has not decreased;For the upper steel frame structure with a diameter of 12 mm,the average maximum acceleration of the entire frame structure can be reduced by 39.21%,35.96%,and 14.64% under the action of Lanzhou wave,Tangshan artificial wave,and El-Centro wave,respectively.In summary,the isolation device has a certain isolation effect in some cases,and its isolation effect is related to different superstructures and different seismic waves.