Buttressing by floating ice shelves at ice-sheet grounding lines is an important process that affects ice retreat and whether structural failure occurs in deep bathymetry. Here, we use a simple algorithm to better represent 2-D grounding-line curvature in an ice-sheet model. Along with other enhancements, this improves the performance in idealized-fjord intercomparisons and enables better diagnosis of potential structural failure at future retreating Antarctic grounding lines.