Revisiting Ancient Dam Engineering: Stability Assessment of the Alyzia Dam Using Modern Geotechnical Methods
Revisiting Ancient Dam Engineering: Stability Assessment of the Alyzia Dam Using Modern Geotechnical Methods
Abstract
Ancient hydraulic structures such as dams represent remarkable achievements of early engineering, reflecting local geological knowledge and innovative construction techniques. Despite their age, many ancient dams remain structurally significant, necessitating robust methods for assessing their stability and informing conservation strategies. This paper presents a systematic geotechnical approach for evaluating the stability of ancient dams, combining historical information, geotechnical characterization, nonlinear finite element analysis and supplementary analytical checks. The Alyzia Dam in Western Greece, a Classical-period dry stone masonry dam, is analysed as a representative case study. Comprising stepped downstream courses of dry-laid limestone blocks, the dam stands approximately 11 m high with a crest length of about 25 m and was probably built in three construction stages. Historical and archaeological sources provide the basis for reconstructing its geometry and probable hydraulic function, either as a sediment-retention or energy-dissipation structure. Material properties are estimated through conservative engineering judgment and analogues from ancient masonry and modern rubble dams. Two-dimensional coupled seepagestress analyses simulate staged construction, seepage patterns and deformation under both historical operating conditions and current design situations according to Eurocode 7 (CEN 2004a) and Eurocode 8 (CEN 2004b). A verification framework is adopted that mirrors contemporary design of rock-fill flow-attenuation dams, including checks for piping, hydraulic fracture and foundation bearing capacity. Results highlight both the inherent resilience and potential vulnerabilities of ancient dry-masonry dams, offering insight into their original design philosophy and providing quantitative guidance for present-day preservation and monitoring strategies.
Keywords: Ancient dams; Alyzia Dam; Heritage preservation; Finite element analysis; Eurocode 7; Eurocode 8.
Dimitrios Egglezos; Christos P. Tsatsanifos; Emmanouil Tzannidakis
4th International Symposium on the Preservation of Monuments and Historic Sites
Restoration Engineering and Structural Interventions
https://doi.org/10.53243/tc301-2026-107