Theoretical And Experimental Research On One Kind Of Single-layer Folded-plane Grid Shells

The single-layer folded-plane reticulated shell recently proposed is a kind of single-layer reticulated structure composed of triangular lattices, looking like an assemblage of diamonds in appearance. No longer limited to traditional configurations of the existing reticulated shells like cylinder, sphere and ellipsis, such structure embraces variable styles, strong visual appearence and novel patterns. Theoretically it is compatible with any plane figure and architectural desire, and thereby bridges the gap between structural engineering and architecture. This structure can be formed by either beams or links, conducting force along the ridge lines and valley lines between the folded plates. In most cases, it is convenient for the installation of roof plates because the architectural surfaces coincide with the structural folded planes. This paper presents theoretical and experimental studies on this novel structure, summarized as below:(1) Overview of the development history and categorization of large span spatial structures. Present the state of the art of reticulated shell structures and the spatial folded-plane structures.(2) Verify that the pinned single-layer folded-plane reticulated shell is a kind of statically determinate space truss structure via geometric analysis and kinetic analysis.(3) Propose simplified truss models, internal force equilibrium equations and simplified structural behavior calculation method for pinned single-layer folded-plane reticulated shell with circular plane projection under three cases:the original one, the one reinforced by circumferential members, and the prestressed one. Also introduce the prestress optimization method for the prestressed model.(4) Carry out static analysis of the structure under uniformly distributed loads to study how the joint types, the circumferential members and the prestressed annular cables affect the structure's static behaviors. Accordingly, different static behaviors of this structure with different parameters including prestress, cross sections of the members, number of plane elements etc.,are presented. (5)Study the structure's stabilities with regard to different joint types, circumferential members and prestressed annular cables by means of eigenvalue buckling analysis and nonlinear buckling analysis. Also compare the stabilities of single-layer folded-plane reticulated shell structures with variable cross sections, numbers of elements and initial defects, etc.(6)Study the dynamic characteristics of different models of the single-layer folded-plane reticulated shell with different joint types, arrangements of circumferential elements and other parameters mentioned above. Study the time-dependent responses of the structure subjected to simple-support and multi-support seismic excitations in multi-dimensions.(7)Design and fabricate an experimental model of a B6.8 type single-layer folded-plane reticulated shell. Carry out static loading tests on the original, reinforced and prestressed models respectively with full-span loads and half span loads. Construction processes of the prestressed system are also simulated through experiments. According to the comparison and analysis of the experimental data and the theoretical results, this paper propose feasible construction schemes for practical application...