A turbine casing assembly, comprising: a turbine support case having a TSC body defined about a center axis with a TSC flange; and an exhaust case having an exhaust case body defined about the center axis with an exhaust case flange extending radially outwardly from the exhaust case body to a radially-outer wall defining an outer diameter of the exhaust case flange, the exhaust case flange configured to attach the TSC to the exhaust case, the exhaust case having struts circumferentially spaced apart about the center axis, each of the struts extending radially from an inner end to an outer end attached to the exhaust case body, each of the struts extending between a leading edge portion and a trailing edge portion, at least a portion of the leading edge portion at the outer end of each of the struts being positioned radially inwardly of the exhaust case flange along a radial line extending from, and perpendicular to, the center axis through the exhaust case flange, wherein: the TSC body adjacent to the TSC flange is resiliently deformable such that it can deform temporarily and return to its original shape in response to a radial displacement of parts of the exhaust case due to thermal expansion; and the TSC flange has a TSC flange radially-outer wall, a radial thickness of the TSC flange defined from the TSC body to the TSC flange radially-outer wall, characterized in the TSC flange including reinforced portions each being circumferentially aligned with one of the struts upon the TSC being attached to the exhaust case, the TSC flange including other portions each disposed circumferentially between adjacent reinforced portions of the TSC flange, the radial thickness of the reinforced portions being greater than the radial thickness of the other portions, and the exhaust case flange configured to be secured to the TSC flange to abut the TSC flange against the radially-outer wall of the exhaust case flange. a turbine support case having a TSC body defined about a center axis with a TSC flange; and an exhaust case having an exhaust case body defined about the center axis with an exhaust case flange extending radially outwardly from the exhaust case body to a radially-outer wall defining an outer diameter of the exhaust case flange, the exhaust case flange configured to attach the TSC to the exhaust case, the exhaust case having struts circumferentially spaced apart about the center axis, each of the struts extending radially from an inner end to an outer end attached to the exhaust case body, each of the struts extending between a leading edge portion and a trailing edge portion, at least a portion of the leading edge portion at the outer end of each of the struts being positioned radially inwardly of the exhaust case flange along a radial line extending from, and perpendicular to, the center axis through the exhaust case flange, the TSC body adjacent to the TSC flange is resiliently deformable such that it can deform temporarily and return to its original shape in response to a radial displacement of parts of the exhaust case due to thermal expansion; and the TSC flange has a TSC flange radially-outer wall, a radial thickness of the TSC flange defined from the TSC body to the TSC flange radially-outer wall, characterized in the TSC flange including reinforced portions each being circumferentially aligned with one of the struts upon the TSC being attached to the exhaust case, the TSC flange including other portions each disposed circumferentially between adjacent reinforced portions of the TSC flange, the radial thickness of the reinforced portions being greater than the radial thickness of the other portions, and the exhaust case flange configured to be secured to the TSC flange to abut the TSC flange against the radially-outer wall of the exhaust case flange.