| With the development of society and economy in our country, more and more people migrate to cities. The requirement of long span space structure increased and the request of people for these structures also increased. Structures with longer span are required. However, the span of structures with certain structural form and constructed with certain material has insurmountable limit. The long-span space structures are constructed mainly by steel at the present time, and the largest span of these structures can reach to 200m. To exceed this span limit, a feasible way is choosing reasonable structural form and using new materials, lighter but with higher strength.The fiber reinforced plastic (FRP) is just a lightweight and high strength material with many excellent properties, like high specific strength, high specific modulus, easy to be designed and constructed, and good corrosion and fatigue resistance. A structure made by FRP is about 20%-50% lighter than that made by steel. Furthermore, FRP can be used not only to support structural weight, but also as smart sensing material. Until now, FRP has been widely applied in various fields, such as aerospace, defense and civil engineering.One type of FRP material, the carbon fiber reinforced plastic (CFRP), is utilized in this dissertation as the basic material to construct the double-layer grids. Each bar element in the double-layer grids is tube element that is wholly constructed by CFRP material. The property of the CFRP double-layer grids under static and dynamic loads are investigated in this dissertation. Also, the earthquake resistance ability of the CFRP grids is investigated. Then the CFRP double-layer grids are compared with traditional steel grids which has the same span, grid and element section.The main contents are included as follows.First, six CFRP tubes that is divide into two groups are constructed. Performance tests for these CFRP tubes under uniaxial tension and compression load are carried out. The tension strength, together with the stress-strain curves of the specimens up to failure are measured. The failure characteristics of the tubes are observed and analyzed. Also, the compression strength, as well as the stress-strain curves under compression up to the failure of specimen are measured. The failure characteristics of the tubes under compression are analyzed. After that, the stress-strain curves of the specimens under tension and compression load are simulated by utilizing the constitutive model of CFRP tubes. The simulation results and compared with the experimental results.Second, the design method for CFRP double-layer grids is proposed, including the design principle of tube strength, the element buckling analysis method and the general design principle of CFRP double-layer grids. Three typical double-layer grids are designed according to the said design method. Then the finite element software, ABAQUS, is utilized to analyze the inner force distribution of these CFRP double-layer grids under the static load that including the deadweight of the grids and the roof board. The variation of inner force distribution with the arrangement pattern of bearings is also discussed.Third, the seismic responses of a CFRP double-layer grid and a steel double-layer grid under common earthquake and rare earthquake are calculated by ABAQUS. The two grids have the same span, grid arrangement and element section. The inner force distribution and frequencies are compared for these two double-layer grids. Also, the span ability of these two grids are analyzed and compared. The results indicate that the CFRP double-layer grid has better span ability.Finally, the failure mode of CFRP grids under horizontal load, vertical load and three-directional load respectively are analyzed based on the pushover analysis method. The judgement criterion for the failure of CFRP grid is proposed. Also, the design advices controlling the failure mode of the CFRP grid is proposed.
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