Study On Seismic Performance Of The New Insulated Sandwich Concrete Wall Structure

From the promulgation of the"Action Plan for Green Building Creation"by the Ministry of Housing and Urban-Rural Development,to the clear definition of energy-saving and emission reduction,as well as low energy consumption targets during the"14th Five-Year Plan"period,it is evident that green building has become the development trend of the construction industry.With the in-depth study of domestic and foreign researchers,numerous innovative materials and architectural forms have emerged,continuously facilitating the development of energy-efficient buildings and promoting the growth of China’s construction industry under the backdrop of the dual carbon policy.The new insulated sandwich concrete wall is a low-carbon,environmentally friendly,and energy-efficient seismic reduction building system.It is considered to be suitable for low-rise rural buildings.The broad prospects of the new insulated sandwich concrete wall in development are undeniable.However,its seismic performance in the context of building structures remains unclear.Traditional seismic design for buildings focuses on ductile design,which avoiding brittle failure and providing time for occupants to evacuate during earthquakes.However,under this design concept,repairing the structural damage caused by seismic forces comes at a significant cost,sometimes requiring complete reconstruction.Therefore,this thesis adopts a performance-based seismic design concept to investigate the seismic performance of the new insulated sandwich concrete wall structure.The main research contents are as follows:（1）Based on pseudo-static test data,a novel skeletal curve model for the new insulated sandwich concrete wall is proposed.A simplified model of the new wall is established using the finite element software STKO,and the hysteresis curve is drawn.By comparing with pseudo-static test results,the effectiveness of the skeletal curve model is verified.The finite element model was established based on the seismic simulation shaking table test of the 1:3 scale structure model,and the skeleton curve model proposed in this thesis was used to simulate the mechanical properties of the wall.The numerical analysis results are compared with the shaking table test results to validate the accuracy of the numerical model,which lays a foundation for subsequent finite element dynamic time-history analysis.（2）Nonlinear dynamic time-history analysis of the full-scale structure on the shaking table was performed using the incremental dynamic analysis method.Fourteen natural earthquake waves were selected,and appropriate seismic intensity index S_a（T₁,5%）and structural damage indexθ_max were determined.The IDA curve cluster of the insulated sandwich concrete building structure was plotted with S_a（T₁,5%）as the ordinate andθ_max as the abscissa.The performance levels of the structure were classified,and the threshold value forθ_max was provided.（3）Based on the fundamental principles of seismic vulnerability and the results of incremental dynamic analysis,the fragility curve of the insulated sandwich concrete building structure was delineated.The exceedance probabilities of three limit states of the structure were obtained.The seismic fragility curve reveals that the transition from the normal serviceability limit state to the collapse prevention limit state is gradual,indicating good ductility of the insulated sandwich concrete building structure.By introducing the collapse safety reserve coefficient,calculations demonstrate that the collapse safety reserve of the structure meets the requirements.（4）The establishment of a direct correlation between seismic intensity indicators and carbon emissions has been proposed,along with an assessment formula for carbon emissions of the new insulated sandwich concrete wall under different design earthquake intensities.This provides guidance for the structural design of the new insulated sandwich concrete wall.Calculation of the carbon emissions of a single piece of the new insulated sandwich concrete wall indicates that it has a significant energy-saving and emission-reducing effect.