Cover
Vol. 20 No. 1 (2026)

Published: June 30, 2026

Pages: 1-13

Research Article

Behavior of Conduits Embedded Within an Earth Embankment

hersh adnan dalloo 1 Rizgar Ali Hummadi 1
1 Department of Civil Engineering, College of Engineering, Salahaddin University-Erbil/ Erbil- Kurdistan region/ Iraq
History
  • Received: November 12, 2025
  • Revised: December 14, 2025
  • Accepted: December 18, 2025
  • Available Online: June 30, 2026
DOI

https://doi.org/10.37650/ijce200101

Abstract

The behavior of buried steel box conduits under embankment loading is a function of the interaction between the conduit and the surrounding soil. In this experimental study, small-scale steel box culverts were installed in soil chamber and backfilled in layers in laboratory condition. The influence of soil moisture content, dry unit weight and stiffness of the conduits on the deformation of the conduits was studied. The soil was prepared at three moisture conditions: dry side (w = 8.5%, γd= 18.15 kN/m3), optimum moisture content (w = 13%, γd= 19.5 kN/m3) and wet side (w = 15%, γd = 18.69 kN/m3). Two sections of conduits (15x15 cm and 25x15 cm) with different wall thickness were tested and deflections were measured after each backfilling layer using dial gauges. The results indicated that conduits embedded at optimum moisture content had more stable deformation behavior and wet-side soil decreased stiffness and increased deflections. Larger conduit spans gave greater deflections, while greater wall thickness gave less deformation. These results validate the roles of soil arching and soil strength on effective earth pressure acting on buried conduits. The Deflection Efficiency (DE) factor was found to be useful in the interpretation of the measured deflections

Keywords

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