Metasurfaces exhibit an extraordinary ability in modulating flexural waves. Most of the existing studies on them focus on infinite structures, which are difficult to apply to engineering. In this paper, we design a single-phase circular meta-slab with subunits of different thicknesses to realize total reflection of flexural waves, and then we embed the designed meta-slab into a finite and boundary-free plate to isolate omnidirectional vibration. We theoretically indicate that the total reflection is attributed to multiple reflections of the 0^th order diffraction wave and determined by two factors: the central angle of the supercell and the ratio of the wavelength to the sum of the inner and outer radii. To verify the correctness of the theoretical analyses, we design a circular meta-slab and numerically demonstrate its total reflection performances for a wave source individually imposed on the central point of the circular meta-slab, an eccentric point within the circular meta-slab, and a point outside the circular meta-slab. In addition, the simulations and experiments of vibration isolation for a finite and boundary-free plate embedded with the designed circular meta-slab are conducted, and the results show that the designed circular meta-slab omnidirectionally isolates vibrations in broadband. Our design provides a method for vibration isolation and may facilitate the application of metasurfaces in practical engineering.

超表面在调制弯曲波方面表现出非凡的能力。现有的对它们的研究大多集中在无限结构上，难以应用于工程。在本文中，我们设计了一个具有不同厚度子单元的单相圆形元板来实现弯曲波的全反射，然后我们将设计的元板嵌入到有限且无边界的板中以隔离全向振动。我们理论上表明，全反射归因于第 0^次的多次反射。阶衍射波，由两个因素决定：超胞的中心角和波长与内外半径之和的比率。为了验证理论分析的正确性，我们设计了一个圆形元板，并数值证明了其对单独施加在圆形元板中心点上的波源的全反射性能，圆形元板内的一个偏心点，和圆形元板外的一个点。此外，对嵌入设计的圆形超薄板的有限无边界板进行了隔振仿真和实验，结果表明设计的圆形超薄板在宽带范围内实现了全向隔振。