3D打印混凝土球壳结构自支撑临界角及影响参数研究OA

3D printing concrete offers advantages such as digital design and formwork-free layerwise fabrication,providing an innovative solution for the construction of curved architectural structures.However,its self-supporting capability of formwork-free fabrication,which depends on structural configuration and material properties,requires further investigation.This study focuses on 3D-printed concrete spherical shell structures.Mechanical properties of the printing material were characterized,and printing tests for the critical self-supporting angle under different parameter combinations,including shell diameter,number of printing strips,and arc-segment length,as well as finite element simulations,were conducted to reveal the variation patterns of self-supporting construction performance.The results show that spherical shells with full-length circular arc segments exhibit the highest self-supporting capacity because their closed circumferential sections provide higher stiffness and effectively resist deformation.Among segmented shells,the 1/3-arc-length configuration achieves a relatively stable critical self-supporting angle and better self-supporting performance.Increasing the number of printing strips enhances the stiffness of the spherical shell structure and prolongs the deposition time of concrete strips,thereby significantly reducing the critical self-supporting angle and improving the self-supporting capability of the spherical shell.Moreover,as the nominal length-to-thickness ratio increases,the critical self-supporting angle increases accordingly,leading to reduced self-supporting performance.