The Research On Seismic Performance Of Multi-story And High-rise Buildings With Untopped PC Floor In OSL Direction

As a national pillar industry with large energy consumption and high carbon emission ratio year by year,the construction industry,under the background of the new era of rapid development of new technologies,new materials and new industries,and led by the national strategic deployment of " carbon peaking and carbon neutrality",the development of prefabricated building structures with Chinese characteristics,low carbon and green has become the primary problem for the development of national construction industrialization.The primary problem of the development of industrialized construction.The floor is a crucial force bearing and transmitting element of the building that transmits both horizontal loads to the lateral force-resistant elements and vertical loads of the structure.Currently,doubleT slab floors and PC monolithic floors are the most widely used precast reinforced concrete(PC)floors.However,the PC monolithic floor has a significant flaw in that the joints are prone to cracking due to temperature differences and volume shrinkage,resulting in a sharp decline in peak bearing ability.Moreover,the applicability of the double-T slab is restricted in China due to the ribs on the bottom of the slab,which leads to an uneven bottom surface of the floor and a lower net height of the building.Therefore,the research group has developed the discretely connected PC floor(DCPCF)according to relevant standard requirements and actual structural load requirements.The apply of DCPCF in building structures has the advantages of high standardization of components,construction efficiency,and light structural quality etc.,it is suitable for the urban-rural development status in China.According to the research,DCPCF floors flex significantly when subjected to in-plane loads,which significantly affects the structure’s dynamic properties and seismic response.There is no relevant research on the seismic performance of building structures with DCPCF in orthogonal slab laying(OSL)direction.This paper examines the seismic performance in OSL direction of multi-story and high-rise buildings with DCPCF,as well as their dynamic characteristics and seismic response under design seismic intensity.The following are the main research findings:(1)The shaking table test of the building structure with DCPCF was carried out to study its dynamic characteristics and seismic responses in OSL direction.A 1/4-scale model of a 4-story 2-bay single-span structure was tested on the shaking table under the designed seismic excitation to evaluate the structural failure form,dynamic characteristics and seismic responses.The resulting data from these tests were processed and analyzed to explore the transverse dynamic properties and seismic response of fully assembled building structures under seismic loads.These findings provide a basis for designing DCPCF to resist seismic loads in OSL direction and offer insights for verifying the Finite element method of connection components and modeling used in numerical simulations.(2)A nonlinear mechanical model of connections and a structural modeling method suitable for building structures with DCPCF were proposed,which further revealed its dynamic characteristics and seismic response laws.Three finite element analysis models(FEMs)were established in dimensions similar to those of the experimental structure,and the numerical simulation methods was verified through experimental results.FEMs were established for cast-in-situ models and DCPCF structural models with different decking directions,respectively.The differences of dynamic properties,seismic response laws,and diaphragm deformation results in OSL direction were compared and analyzed.According to various standards,the rigid performance of the diaphragm was determined,and the seismic performance in OSL direction of building structures with DCPCF was studied.(3)Several full-scale FEMs of multi-story and high-rise buildings with DCPCF were established to investigate the impact of different connection spacing,slab widths,and total floors on the seismic performance in OSL direction of the building structures.By comparing and analyzing modal properties,inter-story drift rations,in-plane deformation response,and diaphragm rigid determination results of numerical simulation under different parameters,the study summarized the impact of each parameter structural seismic performance in OSL direction.The suitability of multi-story and high-rise buildings with DCPCF was analyzed,and relevant suggestions were proposed to supply a reference.In this paper,the shaking table test and numerical simulation of DCPCF building structure are carried out to study the dynamic characteristics,seismic response law and floor diaphragm performance of DCPCF model in OSL direction,and the parametric analysis of DCPCF multi-story and high-rise buildings building structure in OSL direction is carried out.The results of the study can provide reference and basis for multistory and high-rise buildings with DCPCF.