| As a milestone in engineering seismic research, performance-based seismic research has become the developing trend in seismic research. A lot of theoretical research results have been acquired regarding multi-story buildings, some of which have been implemented in the designing code. While the performance-based seismic research about spatial structures is just at the beginning, far away from forming the effective designing method. The research status in spatial structures is far behind that of multi-story buildings, which severely restricts the application and development of spatial structures. As one kind of spatial structures, single-layer cylindrical latticed shell with longitudinal edge ground supported is taken as the main research object, the performance-based seismic analysis of which is performed in the paper, and the main research contents and results is as follows:(1) Research of Rayleigh damping coefficients in seismic time-history analysis of spatial structuresBased on the maximum strain energy ratio of modes under one dimensional seismic excitation, considering the characteristics of natural vibration and seismic response of spatial structures, the approximate maximum strain energy ratio of modes under three dimensional seismic excitations are firstly deduced with the rational simplifications in the equation, which can quantify the modal contribution of spatial structures under three dimensional seismic excitations. With it as the weight, a multi-mode based weighted least square method is proposed to compute the Rayleigh damping coefficients of spatial structures. Based on the basic theory and assumptions of Rayleigh damping theory, with single-layer and double-layer cylindrical latticed shell with longitudinal edge ground supported as the examples, the comparison between the traditional method and the new method is performed. The results show that, significant error will be induced when the traditional method is used under some ground motions, and the results of the new method are better than those of the traditional method under all the ground motions, so the new method is the general and rational method to compute the Rayleigh damping coefficients in seismic time-history analysis of spatial structures.(2) Research of collapse mechanism of single-layer cylindrical latticed shell with longitudinal edge ground supported under severe earthquakes The collapse mechanism of single-layer cylindrical latticed shell with longitudinal edge ground supported under severe earthquakes are studied with the full-range responses analysis method based on load domain. The results show that, it has very distinct one way mechanical characteristics along the span direction, so the length to width ratio has little influence on the mechanical characteristics, and all the failure modes under severe earthquakes are of the dynamic strength failure kind, and it makes little difference with the basic eigenvalue buckling mode or the basic natural vibration mode as the initial geometrical imperfection, so both can be the initial geometrical imperfection, and the initial geometrical imperfection direction has a great influence on its dynamic response, so both the directions should be considered in seismic response analysis, and the rise to span ratio has no fixed influence pattern on the collapse PGA, and the collapse PGA will decrease with the increase of roof super dead load, but the magnitude of which varies with the shells.(3) Research of seismic damage assessment method of single-layer latticed shellsThe seismic damage assessment method of single-layer latticed shells based on degradation of static stability capacity is proposed. The method has a solid theoretical basis and rational analysis process, and it can be easily implemented. Its application in single-layer cylindrical latticed shell with longitudinal edge ground supported and single-layer latticed dome are studied, and the results show that the method has a high precision especially when the shells near collapse, so it is a rational method in damage assessment of single-layer latticed shells. And the method can be used to quantify the seismic performance levels of single-layer latticed shells, which is a key problem in performance-based seismic analysis of single-layer latticed shells.(4) Research of ground motion intensity measures for single-layer cylindrical latticed shell with longitudinal edge ground supportedThe correlation and effectiveness of ground motion intensity measures for single-layer cylindrical latticed shell with longitudinal edge ground supported under near source ground motions are systematically studied for the first time. And the results show that, since this kind of shell takes on very distinct mechanical characteristics along span direction, the intensity measures of ground motions in span direction have stronger correlation and effectiveness than those in other directions on the whole, and the acceleration spectrum at basic period Sa(T1) is the most appropriate intensity measure while PGA is not. This research result can provide the basis for the probability-based seismic performance assessment of this kind of shells. (5) Research of performance level classification and seismic performance assessment for single-layer cylindrical latticed shell with longitudinal edge ground supportedBased on the performance levels given by , considering the seismic response characteristics of single-layer cylindrical latticed shell with longitudinal edge ground supported, the seismic performances are quantified with the damage index based on the degradation of static stability capacity, and the damage characteristics under each performance levels is given. The seismic performance of the shell with the rise to span ratio of 1/4 is evaluated with the probability-based seismic performance assessment method, and the exceedance probability in one year and design reference period of 50 years for each performance levels are calculated, which shows that the shell has a high seismic performance.
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