A structure is provided. The structure defines a first direction, a second direction, and a third direction, the three directions orthogonal to each other. The structure includes a first section, a second section, and a third section. The first section includes a plurality of unit cells joined together, wherein the first section has a first average tensile strength and a first average crack growth resistance. The second substantially solid section is within and surrounding each unit cell of the plurality of first section unit cells, wherein the second section has a second average tensile strength and a second average crack growth resistance, the second average tensile strength different from the first average tensile strength and the second average crack growth resistance different from the first average crack growth resistance. The third section surrounds the first section and the second section.