The earliest recorded examples of barrel vault construction in Iran, particularly in the Khuzestan province, belong to the Elamite period. Understanding the geometric characteristics of these vaults can contribute to both the comprehension of construction techniques and the conservation of these historical structures while maintaining their original architectural authenticity. This study aims to identify the geometrical and technological factors affecting the arrangement methods influenced by the bonding relationships of elements, the span, and the rise of the vaults, with the goal of reconstructing collapsed sections of these historical barrel vaults. The primary research question is: What are the construction characteristics of Elamite brick-barrel vaults in Khuzestan that are influenced by the bonding of elements and the relationship between span and rise? This research adopts a historical-interpretive methodology, utilizing both library research and field studies. Fifteen barrel-vaulted tombs with square-shaped materials (three from early Elamite, seven from Middle Elamite, one from Neo-Elamite, and four from Elymaean periods) and six tombs with trapezoidal materials were selected based on archaeological reports and field surveys. The findings indicate that the construction techniques included the use of Persian, Roman, and hybrid bonding methods, the employment of pointed arches, a logical relationship between the type of material geometry and vault span, a consistent pattern between span and rise ratios in Elamite and Elymaean periods, and a uniform vault thickness to enhance resistance. This study highlights that the geometry, thickness, span-to-rise ratio, and brick arrangement significantly impact the stability and durability of barrel vaults, providing valuable insights for reconstructing collapsed vaults from this historical period.