体内张拉成形空间网格结构垂跨比和矢跨比影响分析及试验研究

Analysis and experimental study on ISFSL affected by sag-span ratio and rise-span ratio

为进一步明确体内张拉成形空间网格结构受力性能,以垂跨比和矢跨比为外形设计参数,根据结构张拉成形后的矢跨比和垂跨比组合的不同,建立12个体内张拉成形空间网格结构计算模型;选用ANSYS有限元程序,通过理论分析详细的研究垂跨比和矢跨比对结构轴力、弯矩和应力的影响特点;设计制作了2个跨度为4.8m的体内张拉成形空间网格结构模型,进行张拉成形和静载试验,进一步研究其影响特点,对理论分析结果进行验证。结果表明:体内张拉成形空间网格结构的垂跨比及矢跨比是影响结构成形及受荷性能的重要参数,结构成形阶段以弯曲应变为主,受荷阶段以轴向压应变的增加为主,合理的矢跨比和垂跨比组合可以明显改善结构受力性能。

In order to study the mechanical performance of internal stretch forming space lattice structure （ISFSL）, twelve models with different the sag-span ratios and rise-span ratios, were found by taking sag-span ratio and rise-span ratio as design parameters. Mechanics performance about axial force, bending moment and section stress of ISFSL being influenced by rise-span ratio and rise-span ratio was fully analyzed by using ANSYS finite element program. Two experimental models with a long span of 4.8m were designed based on the analysis about ISFSL, tensioned forming and static loading were carried out. The characteristics of ISFSL affected by sag-span ratio and rise-span ratio were further studied, and the theoretical analysis results were verified. The study shows that sag-span ratio and rise-span ratio are the important factors which affect the structural property of ISFSL. Bending strain is the mainly mechanics performance in forming stage of ISFSL, and the increasing compressive strain in axial is the mainly mechanics performance in Loading stage. Reasonable combination of sag-span ratio and rise-span ratio helps to improve structural performance of ISFSL.