Stability of Large Span Single Layer Two-way Grid Cylindrical Shells Strengthened with Cables

The project Expo Axis is one of the landmark buildings of Expo Shanghai 2010, and its structural safety depends largely on the security of the six Sun Valleys, which are the important components of the Expo Axis. The simulation of the whole process of collapse and collision of the sun valley under earthquake action is conducted in this article. In the calculation multiple nonlinear factors are taken into account, such as material nonlinearity, large displacement effect, self-contact collision among the structure members, contact collision between the structure and the ground, etc. Through analyzing the results, a reasonable assessment of the structure of Sun Valley’s performance under the supper-large earthquake is given out. This method can also offer reference to other similar large-span steel single-layer lattice structure’s performance analysis.

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Processing of Ceramic Tapes Into 3-D Shells and its Application to a Small Spherical Stepper Motor

10.1115/imece2001/mems-23815 ◽

2001 ◽

Author(s):

Jun Li ◽

G. K. Ananthasuresh

Keyword(s):

Low Temperature ◽

Cylindrical Shells ◽

Single Layer ◽

Processing Technique ◽

Degree Of Freedom ◽

Shell Structures ◽

Stepper Motor ◽

Active Device ◽

Three Degree Of Freedom ◽

Meso Scale

Abstract Low Temperature Co-fired Ceramic (LTCC) tapes (DuPont, 951 series), originally developed for monolithic packaging of interconnects and hybrid microelectronic circuitry, have been used in the last four years to develop a meso-scale integrated fluidic technology. The LTCC fluidic technology is shown to be versatile, inexpensive, fast, and free of packaging problems. The manufacturing basis for this technology is patterning of individual tapes, which are laminated and co-fired to create a layered 3-D structure. In this paper, we present another attractive facet of this technology by creating 3-D shell structures with a single layer of LTCC tape. The processing technique is illustrated with hemispherical and cylindrical shells that have internal 3-D conduits. A novel three degree-of-freedom spherical stepper motor is also presented as an application of an active device using magneto-statically actuated curved LTCC shells.

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Dynamic Collapse Analysis of Single-Layer Lattice Domes with Supporting Frames

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.835.506 ◽

2016 ◽

Vol 835 ◽

pp. 506-513

Author(s):

Hong Mei Li ◽

Wei Lu ◽

Jun Lin Wang ◽

Xiao Qiang Ren ◽

Jian Heng Sun

Keyword(s):

Single Layer ◽

Shell Structures ◽

Research Subject ◽

Important Research ◽

Geometric Imperfections ◽

Large Span ◽

Geometric Nonlinear ◽

Collapse Analysis ◽

Collapse Behavior

Dynamic collapse analysis is an important research subject for large span single layer reticulated shell structures. In this paper, the dynamic collapse behavior of the single layer reticulated shell with substructure which support the reticulated shell are investigated under the earthquake actions. In the analysis, the geometric imperfections, the material and the geometric nonlinear of the structures are considered. The effects of different stiffness of substructure to the collapse earthquake accelerations and the plastic member distribution of the reticulated shell are investigated.

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Wind-Resistant Analysis for Large-span Single-layer Reticulated Shells

International Journal of Space Structures ◽

10.1260/026635104322988362 ◽

2004 ◽

Vol 19 (1) ◽

pp. 47-59 ◽

Cited By ~ 2

Author(s):

Yuan-Qi Li ◽

Yukio Tamura

Keyword(s):

Single Layer ◽

Large Span

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Comparison of residual stress on different three-dimensional multi-layer welding methods of welded hollow sphere joint in large-span structure by considering latent heat

International Journal of Space Structures ◽

10.1177/0956059919890257 ◽

2019 ◽

Vol 34 (3-4) ◽

pp. 57-73

Author(s):

Nam-Hyok Ri ◽

Zhihua Chen ◽

Yong-Sop Ri ◽

Zhiyao Ma

Keyword(s):

Residual Stress ◽

Latent Heat ◽

Hollow Sphere ◽

Three Dimensional ◽

Single Layer ◽

Welding Residual Stress ◽

Heat Of Fusion ◽

State Change ◽

Large Span ◽

Equivalent State

This article quantitatively evaluated the influence of three-dimensional multi-layer welding on the welding residual stress of super-big diameter welded hollow sphere joint in the large-span spatial steel structure considering the influence of material state change using finite element method. First, this article proposed a conception of equivalent state change time—the virtual time of state change in the analysis of welding and cooling—which represents the heat absorbed or released during the change of solid and fluid states in welding material. The equivalent state change time increases the accuracy of the thermal analysis considering the latent heat of fusion in welding and cooling process. Second, this article simulated the numerical experiments of three welding methods including multi-layer symmetric welding, multi-layer sequential welding, and single-layer symmetric welding, which show that multi-layer symmetric welding not only increases the balance of supporting ability of structure but also decreases the value of maximum tensile residual stress, and it is better than the other two welding methods.

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