scholarly journals A DESIGN METHOD FOR PARTS ARRANGEMENT OF THE HYBRID SINGLE-LAYER LATTICE SHELL USING SUPPLEMENTARY PARTS

Author(s):  
Takashi KANAYAMA ◽  
Kenichi KAWAGUCHI
2013 ◽  
Vol 351-352 ◽  
pp. 775-781
Author(s):  
Fan Wang ◽  
Xiao Rong Pan

There are some limitations on the calculation about effective length factor of the single-layer lattice shell structure`s component by the current specifications. That`s why Euler formula is commonly used to anti-push the effective length in engineering design. In traditional design, one or few components were used to calculate the effective length factor, and the single biggest value is assigned to all components for design. Owing to the coarse method, values of some components` effective length are too large or too small. This paper improved the traditional design method, and used excel in formula programming to calculate effective length factors of all components. Then all factors are assigned to all components for designing by SAP2000. At the end of the article, it explored the difference in this new design method with the traditional design method.


Author(s):  
Yanning Yuan ◽  
Yuchen Zhao ◽  
Xiaoli Xi

Abstract A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.


2021 ◽  
Vol 72 (05) ◽  
pp. 491-502
Author(s):  
LINLIN BAI ◽  
JIU ZHOU

Weft-backed structures with compound weft colours can express the mixed colour effect. However, this structure is not suitable for jacquard fabrics with a double-faced shading effect in the traditional single layer design mode. Taking twenty-thread sateen with a step number (S) of 7 as an example, this paper investigates a design method for compound full-backed structure with three shaded-weave databases (SWDs) by selecting the primary weaves (PWs), designing the compound full-backed technical points and establishing the compound structure database with three SWDs. With this design method, a double-faced shading effect in combination with non-backed and full-backed effects on different sides of the jacquard fabric at the same position is generated. The fabric colour card was produced with three SWDs and three sets of different coloured wefts, and their colour values were measured, followed by an analysis of the compound structures on the reverse side, lightness, colour purity and colour difference (DE*ab) of the specimens. The results showed that the three covering effects on the reverse side, partly covered, critical position and totally covered, could be adjusted by controlling the step number and the transition direction of PW-C. For the specimens on the edges of the fabric colour card, their lightness and colour purity values showed a uniform transition effect along with the shading process; their colour differences ranged from 1.23 to 3.69, both in the range of 2–5, and showed a trace or slight colour difference between two adjacent fabric specimens, indicating that the colour shading effect with the three SWDs is stable.


Author(s):  
Tomomi KANEMITSU ◽  
Kenichi SUGIZAKI ◽  
Yoshiro KAI ◽  
Hisanori TANIGUCHI ◽  
Satoshi TAKI ◽  
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2017 ◽  
Vol 2017 ◽  
pp. 1-13
Author(s):  
Wenbao Wang ◽  
Xuanneng Gao ◽  
Lihui Le

The similarity of each scale model is verified based on the theory of similarity, deriving the similarity law of internal explosions in a single-layer spherical lattice shell structure via dimensional theory, calculated based on models with scaling coefficients of 1, 0.8, 0.6, 0.4, 0.2, and 0.1. The results show that the shock wave propagation characteristics, the distribution of the overpressure on the inner surface, the maximum dynamic response position, and the position at which the earliest explosion venting occurs are all similar to those of the original model. With the decrease of scaling coefficients, the overpressure peak value of the shock waves of each scale model, and the specific action time of the positive pressure zone, as well as specific impulse are increasingly deviated from the original model values; when the scaling coefficient is 0.1, the maximum relative error between the overpressure peak value at the measurement point and the specific action time of the positive pressure zone as well as the specific impulse and the original model value is 4.9%. Thus, it is feasible to forecast the internal explosion effect of the original structure size model by using the experiment results of the scale model with scaling coefficient λ≥0.1.


2012 ◽  
Vol 204-208 ◽  
pp. 3048-3051
Author(s):  
Gan Tang ◽  
Wei Wei Li ◽  
Lin Feng Yin ◽  
Xiao Ming Guo

In the interest of an understanding to the imperfection stability behavior, a model of single layer spherical lattice shell was designed. The size and the pattern of initial imperfections were entirely measured. Automatic harmony loading control system and data acquisition system was used. The experiment plan, method and results have provided reference significance for the study on the stability of spatial lattice shell. The experimental results and the results of measured imperfections method were compared and analysed in detail. It is verified that measured imperfections method can accurately take into account of the effect of initial imperfections and it can be used for the supplementary checking computations of some important finished structures.


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