The Nonlinear Earthquake Response Analysis Of Frame-Supported Multi-Ribbed Slab Structure And Damage Performance Based Seismic Evaluation Methods

Multi-ribbed slab structure(MRSS)is a new structural system with characteristic of saving energy and seismic performance,which have good forward-looking application.At the present time, the significant staged achievements have been made in the study of the theoretical and application of multi-storied and high-rise buildings,while the study of this system in buildings with large space at the bottom still remains weakness.Specially there is a matching problem of bearing capacity and stiffness in the transform storey of frame-supported multi-ribbed slab structure(FSMRSS).So it is highly important for study of seismic performance as well as theoretics and methods of seismic design.The dissertation is devoted to FSMRSS,and studies in the two aspects of the nonlinear earthquake response analysis of FSMRSS and damage performance based seismic evaluation methods have been developed by introducing performance based seismic design thought,which mainly studies its nonlinear performance under horizontal earthquake including the failure mode,hysteretic characteristic, energy dissipation and damage formulas.Some fundamental works have been done for performance based seismic design of FSMRSS.The main studied are as follows:1.This paper presents the results and discussions of experimental study on FSMRSS specimen. The specimen is four scaled models(three 1/2 scale two-storey two-bay models and one 1/3 scale three-storey two-bay model)of FSMRSS.The pseudo-static experiments of the specimens have been executed.The seismic performances under low cyclic loadings,such as the failure procedure,failure mode,beating capacity,deformation features,stiffness,hysteretic characteristic and anti-collapse performance,are studied.The hysteretic parameters of the specimen are obtained by use of hysteretic loops of the test under low cyclic loadings through simulation of force-displacement relations with inelastic analysis program IDARC.The hysteretic parameters obtained can reflect stiffness and strength degradation and slip pinching of the specimen,which provide importent foundation for establishment of the nonlinear analysis model of FSMRSS under earthquakes.2.The nonlinear dynamic time-history analysises of FSMRSS under horizontal earthquakes have been carried out.Aimed at different analysis contents and purpose,different calculating models are proposed,the rationality and accuracy of numerical model are validated through comparing with the test results.The the results of dynamic analyses show good coincidence with the experimental results which also show that proposed model is feasible.The dynamic response and yield mechanism of FSMRSS etc.are carefully studied,which provides more data information for the comprehension of earthquake responses of the structures.The influence of stiffiaess ratio of transform storey on seismic performance of FSMRSS are discussed.A rational value of stiffness ratio of transform storey and amounts of seismic wall at bottom are obtained,which are provided for reference of engineering design.3.The ATC-40 procedure,the improved capacity spectrum method proposed by Chopin and their comparisons are introduced.Chopra improved capacity spectrum method is used into aseismic capability assessment of FSMRSS which the process are present according to China Code by analysis of an example of building.In the meanwhile,Push-over analysis of the test models and the example have been carried out by four kinds of the later load patterns,and also compared with test and dynamic results,which adantability of later load pattems to FSMRSS are studied.4.Based on test results of 15 half-scale multi-ribbed slab wails under monotonic horizontal and low reversed cyclic loading,fsilure pattern,hysteresis behavior,energy dissipation and seismic damage models are analyzed.The conception of phase damage indexes is put forward throuth investigating developments of cumulative damage.By comparing the calculated damage indexes with the observed real damage of the multi-ribbed slab walls,the confine value of phase damage index of the wall is presented.5.Considering fatigue based damage model,hysteretic energy dissipation and damage performance of the test model structures and numerical cases and an example of building of FSMRSS under horizontal earthquakes are sepamtly analyzed.The damage feature and damage time-history response of rib beam and rib column elements and storeies and overall structures under different intensity earthquakes are discussed.Firstly in the level of element the energy dissipation and damage formulas of FSMRSS under horizontal earthquakes are analyzed,witch is important for exploring week parts or storeies of the structure.The establishment of performance levels and quantitative analysis of seismic performance targets,of FSMRSS are discussed,which quantified target parameters based on damage performance are put forward to supply references to seismic evaluation of FSMRSS. 6.Limit state equations of damage reliability analysis of FSMRSS as well as the multi-ribbed panel wall are built in terms of the whole damage indexes(as behavioural parameters)of FSMRSS and the multi-ribbed panel wall.Limit damage indexes are calculated based on test results of FSMRSS and multi-ribbed panel wall models.Through probability and statistical analysis of limit damage indexes,the probability distributions and statistical parameters have been obtained for different probabilistic models,which is necessary for reliability analysis of the FSMRSS and multi-ribbed panel wall based on damage performance.At the same time,probability and statistical characteristic of damage indexes under earthquakes are also are discussed.So an approximate seismic reliability analysis method based on damage performance is provided for the FSMRSS and multi-ribbed panel wall.The originality of this dissertation lies in:1.Establishment of nonlinear dynamic model of FSMRSS and numerical analysis of structureThe hysteretie parameters of the specimen are obtained by use of hysteretic loops of the test under low cyclic loadings through simulation of force-displacement relations with inelastic analysis program IDARC.Aimed at different analysis contents and purpose,a rigid flame-oblique compression bar model and simplify model using degrading control parameters for stiffness and strength degradation and slip pinching.are proposed,which nonlinear dynarnie calculating model of FSMRSS are established.The nonlinear dynamic time-history analysises of FSMRSS under horizontal earthquakes have been first carried out.A rational value of stiffness ratio of transform storey and amounts of seismic wall at bottom are obtained.2.The simplify analysis method of nonlinear earthquake responses of FSMRSS is discussedThe adaptability of later load patterns to FSMRSS in push-over analysis are studied.Chopra improved capacity spectrum method is used into aseismic capability assessment of FSMRSS which the process are present according to China Code by analysis of an example of building.3.The quantified target parameters based on damage performance of FSMRSS and multi-ribbed slab walls are put forwardBased on test results of multi-ribbed slab walls,the conception of phase damage indexes is put forward throuth investigating developments of cumulative damage.According to test and numerical analysis the seismic damage performance levels of FSMRSS are established,which quantified target parameters based on damage performance are put forward.4.The probability and statistical characteristic of limit seismic damage indexes of FSMRSS and multi-ribbed slab walls are analysed.Based on test results of FSMRSS and multi-ribbed panel walls,the probability and statistical characteristic of permitting limit damage indexes are analysed,the probability distributions and statistical parameters have been obtained for different probabilistic models.Limit state equations of damage reliability analysis of FSMRSS as well as the multi-ribbed panel wall are built in terms of the whole damage indexes(as behavioural parameters)of FSMRSS and the multi-ribbed panel wall.So an approximate seismic reliability analysis method based on damage performance is provided for the FSMRSS and multi-ribbed panel wall.